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This invention relates to an improved stereospecific process for producing azetidinones useful as hypocholesterolemic agents and as intermediates for the synthesis of penems.
In a process heretofore utilized to prepare azetidinones, a boron enolate of a butyrimide, prepared from butyric acid and 4(R),5(S)-4-methyl-5-phenyloxazolid in one, and 3-methoxymethylphenyl-acetaldehyde are reacted to form a compound of formula ##STR2## as disclosed in Evans, et al, Tetrahedron Letters, 27 (27), 3119-3122 (1986). The chiral oxazolidinone is displaced by reacting with methoxyamine hydrochloride and trimethylaluminum to form a .beta.-hydroxyhydroxamide. The .beta.-hydroxy group is converted to a mesylate, which is cyclized by treatment with potassium carbonate to form an N-methoxyazetidinone. Finally, the N-methoxyazetidinone is reduced by dissolving metal reduction, using lithium and ammonia, to form an azetidinone of formula ##STR3##
Gage, et al, Organic Synthesis, 68, 77-91 (1989) discloses a process for preparing (2S*,3S*)-3-hydroxy-3-phenyl-2-methyl-propanoic acid from a chiral oxazolidinone. The process is shown in Reaction Scheme I. ##STR4##
Jung, et al, Tetrahedron Letters, 26 (8), 977-980 (1985), disclose a process for converting a .beta.-hydroxy-carboxylic acid to an N-hydroxy-.beta.-lactam. The process is shown in Reaction Scheme II. In addition, Jung, et al incorporate by reference Mattingly, et al, J. Amer. Chem. Soc., 101, 3983 (1979) and Miller, et al, J. Amer. Chem. Soc., 102, 7026 (1980) which disclose methods for the reductive cleavage of N-hydroxy-.beta.-lactams to form .beta.-lactams. ##STR5##
The Evans, et al, process suffers from several shortcomings. In particular, the process has not proved applicable to all azetidinones of formula I, below. With some substrates, the use of trimethylaluminum to form the .beta.-hydroxy-hydroxamide results in a low reaction yield and requires laborious purification procedures to isolate the product. In addition, where the Evans, et al. process is used for preparing compounds of formula I, wherein --A--R.sup.1 (as defined below) is capable of stabilizing a carbo-cation, e.g. wherein --A--R.sup.1 is phenyl, naphthyl or W-substituted phenyl or naphthyl, the mesylate cyclization step is accompanied by epimerization.
The process of Gage, et al, provides an efficient route to .beta.-hydroxy-carboxylic acids. However, the Jung, et al, process for converting such compounds to .beta.-lactams suffers from a lack of generality, giving variable yields of product in the cyclization step, depending upon the substrate employed.
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The invention relates to a device for the display or projection of images or similar information.
Display devices such as cathode-ray tubes and liquid crystal display units have a transparent front wall, most usually made of glass. The image is formed on one side of this wall and is observed on the other side.
The quality of the image observed depends on the physical properties of the material of the wall and on its state, notably the state of the external face.
In the same way, the projection device usually has an output objective and the quality of the projected image may be lowered if the external surface of the projection objective is in poor condition.
The invention can be used to reduce dependence on external disturbances of the state of the external surface of the transparent front wall of the display device or the state of the external face of the projection objective.
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It has generally been appreciated in the art that lowering the temperature of body tissues can limit trauma due to surgery. The present inventors have been involved in using cooling to prevent collateral damage during prostate surgery through the use of an endorectal cooling system (ECB). Their original system included intracorporeal cooling irrigation as an adjunct to endorectal cooling, to induce local hypothermia of the pelvis during radical prostatectomy (and other laparoscopic/robotic procedures) to reduce inflammation and neuromuscular injury and thereby to promote functional recovery outcomes (urinary and sexual function after radical prostatectomy). The cold irrigation creates an additive effect to the endorectal cooling to enhance cooling, clears the operative field of blood to improve visualization, and reduces thermal spread and minimizes collateral injury when using thermal electrocautery for hemostasis; this is particularly important when performing the nerve sparing part of the operation where one tries to minimize damage to the delicate neurovascular bundles. We demonstrated a statistically significant faster rate of continence recovery with hypothermia. This work represented the first ever application of hypothermia to radical prostatectomy. The research manuscript which has now been published in Urology, 2009 Feb. 26, notes, “Adjunctive.”
The present invention concerns cooling of surrounding tissues prior to surgery. A modified Foley catheter is described for providing urethral cooling during and after prostate or other surgery of the urogenital system. Cooling of the urethra is achieved by circulating chilled fluid through a coiled capillary tube that is in contact with the catheter's wall. This cools the urethra as well as urethral sphincter. Additional cooling can be provided by circulating the chilled fluid within the bladder. An improved cautery instrument is also disclosed. This system is a normal cautery instrument equipped with cryogenic emitters disposed about the tips. A blast of cryogenic fluid is emitted just prior to energizing the cauterizing tip to lower the temperature of the tissue to be cauterized.
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1. Field of the Invention
The present invention relates to a transparent rubber-modified styrenic resin composition, more particularly to a resin composition which comprises a copolymer matrix and a rubber-particle-dispersed phase formed from rubbery copolymer and which has good chemical resistance, processability, transparency, and impact resistance.
2. Description of the Related Art
Rubber-modified styrenic resin is known to have high toughness and good processability, and is thus widely used in food containers, packaging materials, and housings of household, electrical appliances and office appliances. However, the conventional rubber-modified styrenic resin is generally opaque, and cannot be used to form a transparent article. In the art, it has been suggested that the styrenic resin be blended with a styrene-butadiene block copolymer. However, the resulting styrenic resin composition is not significantly improved in its toughness, and is thus not satisfactory.
Japanese Laid-Open Patent No. 4-180907 discloses a method for polymerizing styrene and methyl methacrylate in the presence of a styrene-butadiene block copolymer. The resulting resin has enhanced transparency and toughness, but it is not satisfactory in processability. Japanese Laid-Open patent No. 8-239532 discloses a resin composition formed from a styrene-butadiene rubber having 1 to 13.8 wt % of 1,2-vinyl unit and styrene-methylmethacrylate copolymer, which have refractive indexes proximate to each other. This resin composition has an average particle size of 0.1 to 2 xcexcm, with a particle size distribution index of 2 to 5. While this resin composition has improved transparency and impact resistance, its chemical resistance is insufficient.
It has been found by the applicant that by dispersing rubber particles into a copolymer matrix formed from styrenic monomers, (meth)acrylate monomers and vinyl cyanide monomers, and by controlling the specific morphology of rubber particles and specific molecular distribution of the copolymer matrix, a rubber-modified styrenic resin composition of improved transparency and chemical resistance can be obtained.
Therefore, the object of the present invention is to provide a transparent rubber-modified styrenic resin composition having good chemical resistance, good processability, high transparency and good impact resistance.
Accordingly, the transparent rubber-modified styrenic resin composition of the present invention comprises:(1) a rubber particle dispersed phase (A) including a rubbery copolymer which is a block copolymer formed from 10 to 50 weight percent of styrenic monomers and 90 to 50 wt % of dienic monomers; wherein said rubbery copolymer contains a polystyrene block in an amount of 5 to 35 wt %, based on total weight of the rubbery copolymer; and (2) a copolymer matrix (B) which is composed of 12 to 70 parts by weight of styrenic unit, 20 to 80 parts by weight of (meth)acrylate unit, 1 to 20 parts by weight of vinyl cyanide unit, and 0 to 40 parts by weight of other copolymerizable monomer units, based on 100 parts by weight of total monomer units. The content of the copolymer matrix (B) having a molecular weight of 3,000xcx9c50,000 is in an amount of 15 to 50 wt %, based on the total weight of the copolymer matrix (B). The aforementioned unit means monomers which are polymerized into polymeric form and which are composed of the polymer. For example, a styrenic unit is a polymerized styrenic monomer derivative in the polymer.
The rubbery copolymer used in the present invention is a block copolymer prepared by anionic polymerization, in which styrenic monomers and dienic monomers are polymerized in the presence of an organic solvent and an organo-lithium compound as the initiator. The rubbery copolymer has a Moony Viscosity (ML1+4) of 20 to 80 and a solution viscosity of 3 to 60 cps (5 wt % in SM at 25xc2x0 C.). The rubbery copolymer contains more than 8 weight percent of 1,2-vinyl structure of the dienic unit. The rubbery copolymer contains 5 to 35 wt % of polystyrene block. The rubbery copolymer may have the following block structures: homopolymer block structure, random copolymer block structure, tapered block structure, linear structure, and branch structure. Representative examples of the aforementioned structures are as follows:
1. Linear Block Copolymer:
(1) (Axe2x88x92B)n
(2) A(Bxe2x88x92A)n
(3) B(Axe2x88x92B)n
wherein, polymer block A consists essentially of styrenic unit, polymer block B consists essentially of dienic unit, and n is an integer equal to or greater than 1.
2. Branch Block Copolymer:
(1) [(Bxe2x88x92A)n]m+1X
(2) [(Axe2x88x92B)n]m+1X
(3) [(Bxe2x88x92A)nB]m+1X
(4) [(Axe2x88x92B)nA]m+1X
wherein, A and B are as defined above, X is a residue of a coupling agent (such as silicone tetrachloride and tin tetrachloride) or a multi-functional organolithium, and n and m are integers of 1 to 10.
3. Mixtures of the linear block copolymers and the branch block copolymers described in Items 1 and 2, shown above.
Representative examples of the tapered block copolymer are:
Dxe2x88x92D/Sxe2x88x92S (Sxe2x88x92D/S)nxe2x88x92S
Dxe2x88x92Sxe2x88x92D/Sxe2x88x92S D/Sxe2x88x92(Sxe2x88x92D/S)n
Dxe2x88x92Sxe2x88x92D/Sxe2x88x92Sxe2x88x92D Xxe2x88x92[(Sxe2x88x92D/S)n]m+1
Sxe2x88x92Dxe2x88x92D/Sxe2x88x92S Xxe2x88x92[(D/Sxe2x88x92S)n]m+1
D/Sxe2x88x92Sxe2x88x92Dxe2x88x92S Xxe2x88x92[(Sxe2x88x92D/S)nxe2x88x92S]m+1
Sxe2x88x92D/Sxe2x88x92S Xxe2x88x92[(D/Sxe2x88x92S)nxe2x88x92D/S]m+1
(Sxe2x88x92D/S)n Dxe2x88x92D/Sxe2x88x92Sxe2x88x92Sxe2x88x92D/Sxe2x88x92D
wherein, S is polystyrenic block, D is polydienic block, D/S is adienic/styrenic tapered block copolymer, X is the residue of a multi-functional initiator or a multi-functional coupling agent, and m and n are integers of 1 to 10. In the present invention, the tapered block structure is preferred. Among the above-mentioned examples, Dxe2x88x92D/Sxe2x88x92S, Dxe2x88x92Sxe2x88x92D/Sxe2x88x92S, and Dxe2x88x92D/Sxe2x88x92Sxe2x88x92Sxe2x88x92D/Sxe2x88x92D are more preferred.
The rubbery copolymer of the present invention contains the polystyrene block in an amount of 5 to 35 weight percent, preferably 10 to 25 wt %, more preferably 14 to 22 wt %, based on total weight of the rubbery copolymer. When the content of the polystyrene block is less than 5 wt %, the resin composition is poor in transparency. On the other hand, when the content of the polystyrene block is more than 35 wt %, the impact strength of the resin composition would not be satisfactory. The content of 1,2-vinyl structure of the rubbery copolymer used in the present invention is more than 8 wt %, preferably more than 14 wt %. When the content of the 1, 2-vinyl structure is more than 14 wt %, a better balance of good transparency and high impact resistance of the resin composition can be attained.
Examples of the styrenic monomers of the rubbery copolymer of the present invention are styrene, xcex1-methyl styrene, para-methyl styrene, meta-methyl styrene, ortho-methyl styrene, ethyl styrene, 2,4-dimethyl styrene, para-tert-butyl styrene, xcex1-methyl-para-methyl styrene, bromo-styrene, dibromo-styrene, and 2,4,6-tribromo-styrene. The aforementioned styrenic monomers can be used alone or in combination with one another.
Examples of the dienic monomers of the rubbery copolymer of the present invention are 1,3-butadiene, 2-methyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 2,3 -dimethyl-1,3-butadiene, isoprene, and 1,3-hexadiene. The aforementioned monomers can be used alone or in combination with one another. Among the aforementioned monomers, 1,3-butadiene and isoprene are preferred.
The organolithium compound used in the preparation of the rubbery copolymer is a compound containing at least one lithium atom. Examples of organolithium initiators are ethyllithium, n-pentyllithium, iso-propyllithium, n-butyllithium, sec-butyllithium, hexyllithium, cyclohexyllithium, phenyllithium, benzyllithium, naphthyllithium, tert-butyllithium, tri-methylene di-lithium, tetra-methylene di-lithium, butadiene di-lithium, and isopentadiene di-lithium. The aforementioned organolithium compounds can be used alone or in combination with one another.
The polymerization rate, the content of the 1,2-vinyl structure, and the random structures of the dienic unit and the styrenic unit can be adjusted with the use of a polar compound or a randomizer. The polar compound and the randomizer are selected from the group consisting of ethers, amines, thio-ether, alkylbenzene, sulfonate salt, potassium alkyl oxide and sodium alkyl oxide.
The transparent rubber-modified styrenic resin composition of the present invention contains 1 to 40 wt % of the rubbery copolymer. When the content of the rubbery copolymer is less than 1 wt %, the impact resistance of the resin composition would be inefficient. When the content of the rubbery copolymer is more than 40 wt %, the transparency and the processability would not be satisfactory.
In the present invention, the copolymer matrix (B) is composed of styrenic unit in an amount of 12 to 70 parts by weight, (meth)acrylate unit in an amount of 20 to 80 parts by weight, vinyl cyanide unit in an amount of 1 to 20 parts by weight, and other copolymerizable monomer units in an amount of 0 to 40 parts by weight. In view of better balance of chemical resistance, stiffness, and transparency required in the present invention, the amount of the vinyl cyanide unit is preferably 2 to 12 parts by weight, more preferably 2 to 10 parts by weight. Examples of the styrenic monomers of the styrenic unit described above are the same as those described in the preparation of the rubbery copolymer, and are not further explained hereinafter.
The (meth)acrylate monomers of the (meth)acrylate unit described above are selected from methacrylate monomers and acrylate monomers. Examples of methacrylate monomers are methyl methacrylate, ethyl methacrylate and butyl methacrylate. Examples of acrylate monomers are methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-methylpentyl acrylate, 2-ethylpentyl acrylate, and octyl acrylate. Methyl methacrylate, n-butyl acrylate and methyl acrylate are preferred. Examples of the vinyl cyanide monomers of the vinyl cyanide unit are acrylonitrile and xcex1-methyl acrylonitrile. The vinyl cyanide unit is in an amount of 1 to 20 parts by weight. When the content of the vinyl cyanide unit is less than 1 part by weight, the chemical resistance and tensile strength of the resin composition will be poor. When the content of the vinyl cyanide unit is more than 20 parts by weight, the transparency, color appearance and processability of the resin composition would be worse.
The copolymerizable monomers for use in preparing the copolymer matrix (B) are not limited to any specie provided that the resulting resin composition attained a desired transparency. Examples of the copolymerizable monomers include unsaturated fatty acids, such as itaconic acid, maleic acid, fumaric acid, butenic acid, and cinnamic acid; maleimide-based monomers, such as N-methyl maleimide, N-ethyl maleimide, N-butyl maleimide, N-octyl maleimide, N-isopropyl maleimide, N-phenyl maleimide, N-para-bromo-phenyl maleimide, N-ortho-chloro-phenyl maleimide, and N-cyclohexyl maleimide; unsaturated carboxylic anhydrides, such as maleic anhydride, itaconic anhydride, and citraconic anhydride; amine-containing unsaturated compounds, such as propenyl amine, allyl amine, diethylaminoethyl (meth)acrylate and dimethylaminopropyl (meth)acrylate; and acrylamide-based compounds, such as acrylamide and N-methyl acrylamide.
The content of the copolymer matrix (B) in the resin composition of the present invention having a molecular weight of 3,000xcx9c50,000 is in an amount of 15 to 50 wt %, preferably 20 to 45 wt %, more preferably 25 to 40 wt %, based on the total weight of the copolymer matrix (B). When the content of the copolymers having a molecular weight of 3,000xcx9c50,000 is greater than 15 wt %, the processability of the resin composition is good. When the content of the copolymers matrix having a molecular weight in the aforementioned range is lower than 50 wt %, the impact strength and the chemical resistance of the resin will be better. As such, the resin composition can have high impact resistance, good processability and chemical resistance.
The copolymer matrix (B) in the present invention may be linear or branch in polymer chain structure. When the copolymer matrix (B) is a branch structure, a better balance of impact strength and processability of the resin composition can be obtained. The branch copolymer matrix (B) can be prepared by adding one or more of a multi-functional unsaturated monomer, a multi-functional initiator, and a multi-functional chain transfer agent during polymerization.
The content of rubber particles having at least four occlusions are 2 to 20%, preferably 3 to 15%, more preferably 3 to 10%, based on the total number of rubber particles of the rubber-particle-dispersed phase (A). The content of rubber particles having no occlusions is 20 to 80%, preferably 30 to 75%, more preferably 40 to 70%, based on the total number of rubber particles of the rubber-particle-dispersed phase (A). When the morphology of the rubber particles of the resin composition is within the aforementioned ranges, better transparency and impact strength can be obtained.
The so-called xe2x80x9cocclusionxe2x80x9d is a styrenic-(meth)acrylate-acrylonitrile- (optionally co-monomer) copolymer particle encapsulated within the rubber particle, and which occlusion particle size is greater than or equal to 0.05 xcexcm. The rubber particle having no occlusions means that the rubber particle does not contain any occlusions as described above. Of course, the rubber particle having encapsulated styrenic-(metha)acrylate-acrylonitrile-(optionally co-monomer) copolymer particles which are smaller than 0.05 xcexcm in size is also inside the definition of xe2x80x9crubber particles having no occlusionsxe2x80x9d.
The haze of the resin composition of the present invention can be kept at a level below 11.0 (ASTMD-1003, thickness 3 mm) by adjusting the polymerization conditions, the addition of additives, and the conditions of the devolatilizing and extrusion steps.
In the resin composition of the present invention, the weight average molecular weight of the copolymer matrix (B) is not particularly limited, and is typically in the range of 50,000xcx9c300,000, preferably in the range of 60,000xcx9c200,000, more preferably in the range of 70,000xcx9c150,000. When the weight average molecular weight is higher than 50,000, the impact resistance of the resin composition is good. When the weight average molecular weight is lower than 300,000, the processability (flowability) and the transparency of the resin composition are good. The weight average particle size of the rubber particles of the resin composition of the present invention is not particularly limited, and is typically in the range of 0.1 to 2.0 xcexcm, preferably in the range of 0.1 to 1.5 xcexcm, more preferably in the range of 0.2 to 1.0 xcexcm. When the weight average particle size of the rubber particles is not smaller than 0.1 xcexcm, the impact strength of the resin composition is good. When the weight average particle size of the rubber particles is not larger than 2.0 xcexcm, the transparency of the resin composition would be good. The morphologies of the rubber particles, including weight average particle size of the rubber particles and the content of rubber particles having occlusions or not as mentioned above, are determined by cutting a thin section from the resin composition, and photographing the thin section with the use of a transmission electron microscope (TEM). The rubber morphologies are determined with at least 200 rubber particles on the TEM photograph. The weight average particle size can be calculated through the following formula:
Weight average particle size=xcexa3niDi4/xcexa3niDi3
wherein ni is the number of rubber particles having a diameter of Di.
The gel content (insoluble parts of the resin composition) is not particularly limited, and is typically in the range of 2 to 40 wt %, preferably in the range of 8 to 35 wt %, more preferably in the range of 12 to 30 wt %. When the gel content is not less than 2 weight percent, the impact strength of the resin composition would be good. When the gel content is not more than 40 wt %, the flowability, the processability and the transparency of the resin composition would be good. Besides, the swelling index of the resin composition of the present invention is not particularly limited, and is typically in the range of 2 to 25, preferably in the range of 3 to 20, more preferably in the range of 5 to 15. When the swelling index of the resin composition is in the range of 2 to 25, the balance of impact strength and transparency of the resin composition is good.
The gel content of the resin composition and the swelling index of the resin composition are determined by dissolving 1 gram of the resin composition in a solution containing toluene and acetone (in a volume ratio of 1:1) at a temperature of 25xc2x0 C. for twenty-four hours. The solution mixture is then centrifuged at 15000 rpm for 20 minutes to separate into two phases. The lower part (phase) which contains the insoluble gel in swelled form is removed, and is vacuum-dried at 80xc2x0 C. for 12 hours to obtain the insoluble gel in dried form. The gel content (wt %) of the resin composition is calculated through the following formula:
Gel content (wt %)=(weight of the insoluble gel in dried form)/(weight of the resin composition)xc3x97100%
The swelling index is calculated through the following formula:
Swelling index=(weight of the insoluble gel in swelled form)/weight of the insoluble gel in dried form)
The rubber-modified styrenic resin composition of the present invention can be prepared by polymerizing styrenic monomers, (meth)acrylate monomers, vinyl cyanide monomers, and optionally, other copolymerizable monomers in the presence of the rubbery copolymer via bulk or solution graft polymerization with a continuous or batch process. In the case of continuous solution polymerization, the aforementioned rubbery copolymer and monomers are added with a suitable solvent to form a solution of raw material mixtures, which is allowed to dissolve within a dissolving tank having high shear and high stirring rate. The dissolving tank could be one having a screw-type agitator or other types of agitators capable of generating high shear. After a sufficient period of mixing time, the rubbery copolymer is completely dissolved to form a rubber solution which can be conveniently delivered to a reactor by pumping. The aforementioned raw material solution or monomers is fed continuously into a first and/or a second reactor and/or a subsequent reactor. The chain transfer agent and the initiator are added as required into the first reactor and/or the second reactor and/or the following reactor for graft polymerization.
The aforementioned reactor could be a continuous stirring tank reactor (CSTR), a plug flow reactor, a static mixer type reactor, or a combination of the same type or different types of the aforementioned reactors. The reaction temperature is controlled to be in the range of 70 to 230xc2x0 C. The final conversion of monomers is in the range of 30 to 95%, preferably in the range of 50 to 90%.
Preferably, the first reactor is a continuous stirring tank reactor (CSTR), and is connected with the second and/or the following reactors, which could be a continuous stirring tank reactor, a plug flow reactor or a static mixer type reactor.
The conversion in the first reactor is typically in the range of about 1 to 30 wt %, preferably 2 to 25 wt %, more preferably 3 to 22 wt %. The conversion in the first reactor is adjusted according to the amount, the species, and the viscosity of the rubbery copolymer such that phase inversion of the rubber does not occur in the first reactor, and occurs in the subsequent reactors (i.e., the second or the third reactor) to result in good physical properties.
The solvent for use in the polymerization of the transparent rubber-modified styrenic resin composition of the present invention can be selected from the group consisting of aromatic hydrocarbons, ketones, and esters. Among the aromatic hydrocarbons, toluene, ethylbenzene, and xylene are preferred. Among the ketones, butanone is preferred. Among the esters, ethyl acetate is preferred. Besides, aliphatic hydrocarbons, such as n-hexane, cyclehexane and n-heptane, could be used as the solvent.
The amount of the initiator added during the polymerization of the transparent rubber-modified styrenic resin composition of the present invention is 0 to 2 parts by weight, preferably 0.001 to 0.7 part by weight based on 100 parts of monomers. Examples of the initiators are benzoyl peroxide, dicumyl peroxide, t-butyl peroxide, t-butyl hydroxy peroxide, cumene hydroperoxide, t-butyl peroxy benzoate, di-2-ethylhexyl peroxy dicarbonate, tert-butyl peroxy isopropyl carbonate (BPIC), cyclohexanone peroxide, 2,2xe2x80x2-azo-bis-isobutyronitrile, 1,1xe2x80x2-azo-bis-1-cyclohexane carbonitrile, 2,2xe2x80x2-azo-bis-2-methyl butyronitrile, azo-bis-isobutyronitrile, 1,1-di-t-butyl peroxy cyclohexane (TX-22), 1,1-di-t-butylperoxy-3,3,5-trimethyl cyclohexane (TX-29A), 2,5-dimethyl-2,5-bis- (2-ethylhexanoxyperoxy)hexane, 4-(t-butyl peroxy carbonyl)-3-hexyl-6-[7-(t-butyl peroxy carbonyl)heptyl]cyclohexane, di-t-butyl-diperoxyazelate), 2,5-dimethyl-2,5-bis-(benzoyl peroxy)hexane, di-t-butyl peroxy-hexahydro-terephthalate (BPHTP), and 2,2-bis-(4,4-di-t-butyl peroxy)cyclohexanyl propane.
The amount of the chain transfer agent added during the polymerization of the styrenic resin composition of the present invention is in the range of 0 to 2 parts by weight, preferably 0.01 to 0.7 part by weight based on 100 parts by weight of monomers. Examples of the chain transfer agent are as follows:
(1) Mercaptans, such as methyl mercaptan, n-butyl mercaptan, cyclohexyl mercaptan, n-dodecyl mercaptan, stearyl mercaptan, t-dodecyl mercaptan (TDM), n-propyl mercaptan, n-octyl mercaptan, tert-octyl mercaptan, and tert-nonyl mercaptan.
(2) Alkyl amines, such as ethylamine, diethylamine, triethylamine, isopropylamine, diisopropylamine, dipropylamine, butylamine, di-n-butylamine, and tri-n-butyl amine.
(3) Pentaerythritol tetrakis(3-mercapto propionate), pentaerythritol tetrakis(2-mercapto ethanate), pentaerythritol tetrakis(4-mercapto butanate), pentaerythritol tetrakis(5-mercapto pentanate), pentaerythritol tetrakis(6-mercapto hexanate), trimethylolpropane tris(2-mercapto ethanate), trimethylolpropane tris(3-mercapto propionate) (TMPT), trimethylolpropane tris (4-mercapto butanate), trimethylolpropane tris (5-mercapto pentanate), and trimethylolpropane tris (6-mercapto hexanate).
Other examples of the chain transfer agent are pentaphenylethane, xcex1-methyl styrene dimer, and terpinolene.
The aforementioned multifunctional unsaturated monomers are added in an amount of 0 to 1 part by weight, preferably 0.005 to 0.6 part by weight based on 100 parts by weight of monomers. Examples of the multi-functional unsaturated monomers are:
(1) Vinyl benzene based monomers, such as divinyl benzene, 1,2,4-trivinyl benzene, and 1,3,5-trivinyl benzene.
(2) Dimethacrylate monomers, such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-propylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, 1,6-hexanene glycol dimethacrylate, neopentyl glycol dimethacrylate (PGDMA), dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and 2,2-bis-(4-methacryloxy diethoxy phenyl) propane.
(3) Trimethacrylates, such as trimethylol propane trimethacrylate, and triethylol ethane trimethacrylate.
(4) Diacrylates, such as ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, 1,3-di-propylene glycol diacrylate, 1,4-di-butylene glycol diacrylate, 1,6-hexylene glycol diacrylate, neopentyl glycol diacrylate (PGDA), dipropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2-bis (4-acryloxy propoxy phenyl)propane, and 2,2-bis (4-acryloxy diethoxy phenyl)propane.
(5) Triacrylates, such as trimethylol propane triacrylate, and triethylol ethane triacrylate.
(6) Tetraacrylates, such as tetramethylol methane tetraacrylate.
After the polymerization is completed, the resulting copolymer solution is removed from the reactor, and is devolatilized through the devolatilizing device for removing volatile components, such as unreacted monomers and solvent, to produce the transparent rubber-modified styrenic resin composition of the present invention.
The devolatilizing device could be a single or twin screw extruder with at least one degassing vent. If necessary, stripping agents, such as water, cyclohexane, and carbon dioxide, may be added into the extruder. The extruder may be provided with a kneading zone and a pumping zone. The screw rotates at a rate in the range of 120 to 350 rpm. Alternatively, a devolatilizing tank with vacuum may be used. Devolatilization can be accomplished through a single devolatilizing tank or through a plurality of the devolatilizing tanks that are connected in series or the combination of devolatilizing tank and extruder. The temperature of the devolatilizing tank is controlled to be in the range of 180 to 350xc2x0 C., preferably in the range of 200 to 320xc2x0 C., more preferably in the range of 220 to 300xc2x0 C. The devolatilizing tank is controlled at a degree of vacuum below 300 Torr, preferably below 200 Torr, more preferably below 100 Torr. other kinds of devolatilizing devices, such as a thin film evaporator, may also be used.
After the devolatilization stage, the content of volatile components of the styrenic resin including residual monomers, solvent, dimers and trimers, is reduced to a level below 1 wt %, preferably below 0.8 wt %, more preferably below 0.5 wt %.
As long as the properties of the styrenic resin composition of the present invention is not significantly and adversely affected, other additives maybe added into the composition. The additives include coloring agents, fillers, flame retardants, flame retarding aids (such as antimony trioxide), light stabilizers, thermal stabilizers, plasticizers, lubricants, releasing agents, stickening agent, anti-static agents, antioxidants, and electrical conduction additives. Examples of the additives are mineral oil, ester-based plasticizers such as butyl stearate, polyester-type plasticizers, polyorganosiloxanes such as polydimethylsiloxanes, fatty acids and their metal salts, hindered amine-based anti-oxidants, and glass fibers. The additives can be used alone or in combination with one another, and can be added during the polymerization or after the polymerization is completed.
The ester-based plasticizer or the mineral oil is used in an amount of 0 to 5 wt %, preferably 0.05 to 2 wt %, based on the weight of the resin composition. The polyorganosiloxane is used in an amount of 0 to 0.5 wt %, preferably 0.002 to 0.2 wt %.
As long as the transparency of the styrenic resin composition of the present invention is not significantly and adversely affected, other resins may be added into the composition. The resins include styrenic-(meth)acrylate-acrylonitrile copolymer, styrenic-(meth)acrylate copolymer, styrenic-(meth) acrylate-acrylonitrile-maleimide copolymer, styrenic-(meth)acrylate-maleimide copolymer, (meth)acrylate-maleimide copolymer, and dienic rubber-modified resin of the aforementioned copolymer (e.g. blended with or grafted with rubbery polymer).
The aforementioned resin is used in an amount of 0 to 200 parts by weight based on 100 parts by weight of the transparent rubber-modified styrenic resin composition, and it can modify or promote heat-resistance, tensile strength and processability of the resin composition.
Processing of the transparent rubber-modified styrenic resin composition of the present invention is not particularly limited. The present invention is suitable for injection molding, compression molding, extrusion molding, blow molding, thermoforming, and vacuum forming.
In preparing the transparent rubber modified styrenic resin composition, the styrenic resin and other additives or other resins are blended by using a conventional mixing device, such as Brabender plastificator, Banbury mixer, a roll kneader, and a single or twin-screw extruder. After extrusion, the resulting resin is cooled and pelletized. The blending procedure is typically conducted at a temperature in the range of 160 to 280xc2x0 C., preferably in the range of 180 to 250xc2x0 C.
The present invention is more specifically described and explained through the following examples and tests of physical properties. Unless otherwise indicated, the parts and percents are all based on weight in the Examples. It is to be understood, however, that the following Examples are merely illustrative and are not intended to limit the scope of the invention.
(1) Processability(flowability, MI): The melt index of the styrenic resin is tested under 200xc2x0 C.xc3x975 kg according to ASTM D-1238.
(2) Chemical resistance (oil resistance): A 230 mm (length)xc3x972 mm (thickness) test piece of the resin composition is formed by injection molding, and measured by a bending form tester. The surface of the test piece is coated with olive oil and is then placed in the bending form tester with a curved bow shape at room temperature for 6 hours. Thereafter, the appearance of the test piece is inspected.
∘: No change was found in the appearance of the test piece.
xcex94: Small cracks were found in the appearance of the test piece.
X: Large cracks were found in the appearance of the test piece.
(3) Izod impact strength: Determined according to ASTM D-256 (A notched test piece with a thickness of xc2xc inch is tested at 23xc2x0 C.).
(4) Transparency (Haze): A 3 mm thick test piece is formed by injection molding and is tested according to ASTM D-1003. A high value of Haze indicates that the resin composition has poor transparency.
(5) Determination of the content (wt % ) of the copolymer matrix (B) having a molecular weight in the range of 3,000xcx9c50,000: The styrenic resin composition is dissolved in tetrahydrofuran (THF). The insoluble part is removed by centrifuge. The molecular weight distribution of the soluble parts is determined by gel permeation chromatography (GPC) using polystyrene as the standard. On the GPC chart, the area corresponding to molecular weight in the range of 3,000xcx9c12,000,000 is integrated and is taken as X1. The area corresponding to molecular weight in the range of 3,000 to 50,000 is integrated and is taken as X2. The content of the copolymer matrix (B) having a molecular weight in the range of 3,000xcx9c50,000 is X2/X1xc3x97100 wt %. The GPC is conducted under the following parameters:
Column: KD-806M; Detector: RI-410, UV-486; Mobile phase: THF(flow rate 1.0 c.c./min).
(6) Determination of the content of polystyrene block in rubbery copolymer (wt %): The rubbery copolymer is dissolved in 1,2-di-chloro-benzene (35 ml) with heating. The solution is then added with t-butyl hydroperoxide solution (10 ml) and osmium tetraoxide solution (1 g OsO4/1L toluene), and is continuously heated and stirred for 15 minutes. After cooling, the solution is added with 350 ml of methanol and 5 drops of sulfuric acid, and is stirred. Then, the solution is filtered through a filter paper, and the residue is dried and weighted.
Content of polystyrene block (wt %)=(weight of dried residue after filtering)/(weight of the rubber copolymer)xc3x97100%
(7) The content(%) of 1,2-vinyl structure in the rubbery copolymer is determined by IR analysis.
(8) Determination of content (%) of occlusions of the rubber particles: The resin composition is microtomed and photographed by transmission electron microscope to get a 25,000-times magnified photograph. A 12 cmxc3x9716 cm area on the photograph is taken into consideration. N is the total number of the rubber particles. N1 is the number of rubber particles having at least four occlusions (with occlusion sizexe2x89xa70.05 xcexcm). N2 is the number of rubber particles having occlusions of smaller than 0.05 xcexcm or without any occlusions.
N1/Nxc3x97100%=content(%) of rubber particles having at least four occlusions
N2/Nxc3x97100%=content(%) of rubber particles having no occlusions
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The invention relates in general to batch biological and chemical and analysis of large numbers of samples. More specifically it relates to a fast response thermal cycler that carries a large batch of samples through one or more predetermined temperature profiles.
In biological and chemical testing and experiments it is often necessary to repeatedly cycle samples of a biological specimen or chemical solution through a series of different temperatures where they are maintained at different set temperatures for predetermined periods of time. While single sample processing can be used, many experiments, particularly ones in modern biological experimentation, require the use of large numbers of samples. Modern biological testing often uses micro-titration plates. A standard such plate is a plastic sheet with 96 depressions, each adapted to hold one of the samples to be processed. The plastic is sufficiently thin that the sample can readily reach a thermal equilibrium with a conductive mass at the opposite face of the plastic sheet. Testing also often requires a large number of cycles in each experiment, e.g. fifty. For cost effective processing it is therefore important to reach and stabilize at a set temperature rapidly. It is also cost effective, and sometimes necessary, to process a large number of samples in each experimental run. A plate of 96 samples is more cost effective than the processing of samples one by one.
Various devices and techniques are known for the thermal cycling of multiple samples. The most common technique utilizes thermoelectric devices. The apparatus sold by M. J. Research Inc. under the trade designation "Minicycler" is typical. It uses all solid state electronics and the Peltier effect. Conventional refrigeration techniques are also known, as is the combination of electrical heating and water cooling, as used in a device sold by Stratagene Inc. under the trade designation Temperature Cycler SCS-96.
These devices operate reasonably well, but they operate on only one plate. One problem with somehow expanding these devices to handle multiple plates is that a uniform temperature profile for a large number of plates requires multiple temperature sensing devices at various locations and a way to vary the temperature quickly and reliable at any portion of the samples. Another problem is that any malfunction or diminution of function of any component requires a repair of a complex system that extends over this large area. Repairs can disable the entire unit, and they can be slow and expensive. A further problem is that known cyclers, regardless of claims to be able to move to a new temperature rapidly, are nevertheless comparatively slow, regardless of the number of plates being processed. For example, a typical thermoelectric unit takes 210 to 230 seconds to go from room temperature to 94.degree. C. and stabilize there. If an experiment requires 50 different temperature cycles of this magnitude, then 3 to 4 hours is used just in cycling to new temperatures. This is a significant source of delay in conducting the experiment, and a significant element of cost.
It is therefore the principal object of the invention to provide a thermal cycler and a method of operation with a high sample volume, good temperature control, and fast response time to yield a high throughput that is multiple times greater than throughputs attainable heretofore.
Another object of this invention is to provide a foregoing advantages while also providing extreme ease of maintenance of the cycler.
A further object is to provide a cycler which is highly flexible and can be adapted to process a variety of sample holders, or to receive the samples directly.
Still another object is that it provides the foregoing advantages while also allowing the simultaneous running of different temperature profiles.
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The following abbreviations which may be found in the specification and/or the drawing figures are defined as follows:
ACK acknowledgement
D2D device-to-device
eNB, eNodeB evolved Node B/base station in an E-UTRAN system
E-UTRAN Evolved UTRAN (LTE)
FDD frequency division duplex
GSM Global System for Mobile Communications
HARQ hybrid automatic repeat request
LTE Long Term Evolution
LTE-A Long Term Evolution Advanced
M2M machine-to-machine
MTC machine-type communication
NACK negative acknowledgement
OFDM orthogonal frequency-division multiplexing
PDSCH physical downlink shared channel
PDCCH physical downlink control channel
PHICH physical HARQ indicator channel
PUCCH physical uplink control channel
PUSCH physical uplink shared channel
RTT round trip time
TDD time division duplex
Tx transmission
UE user equipment
UMTS Universal Mobile Telecommunications System
UTRAN Universal Terrestrial Radio Access Network
WCDMA Wideband Code Division Multiple Access
D2D communications have been the subject of increasing research in recent years. D2D encompasses direct communication among portable devices without utilising nodes/base stations of an infrastructure-based wireless network (typically a cellular network, such as GSM, WCDMA, LTE or the like). D2D communications reduce the load on base stations/wireless networks and also presents new service opportunities. There is a subset of D2D commonly termed M2M (or equivalently MTC) which refers to automated communications from and to radio devices that are not user-controlled, such as for example smart meters, traffic monitors and many other types. Typically, M2M communications are infrequent and carry only small amounts of data compared to cellular communications and D2D communications that are not M2M. To keep costs low, given their more focused purposes, many M2M devices have quite limited capabilities as compared to conventional UEs.
Specific to LTE and LTE-A systems, there has been proposed a study item to evolve the LTE platform in order to cope with the demand of such D2D communications by studying enhancements to the LTE radio layers that allow devices to discover each other directly over the air and potentially communicate directly when viable, taking system management and network supervision into account. See for example documents Tdoc-RP-110706 entitled “On the need for a 3GPP study on LTE device-to-device discovery and communication”; Tdoc RP-110707 entitled “Study on LTE Device to Device Discovery and Communication—Radio Aspects”; and Tdoc-RP-110708 entitled “Study on LTE Device to Device Discovery and Communication—Service and System Aspects”; each by Qualcomm, Inc; TSG RAN #52; Bratislava, Slovakia; May 31-Jun. 3, 2011. Document RP-110106 describes one of the main targets is that the “radio-based discovery process needs also to be coupled with a system architecture and a security architecture that allow the 3GPP operators to retain control of the device behaviour, for example who can emit discovery signals, when and where, what information do they carry, and what devices should do once they discover each other.”
One 3GPP working group is currently discussing and defining use cases and service requirements for the D2D. Such use cases include social applications, local advertising, multiplayer gaming, network offloading, smart meters and public safety. Specifically, social applications can use D2D for the exchange of files, photos, text messages, etc, VoIP conversations, one-way streaming video and two-way video conferencing. Multiplayer gaming can use D2D for exchanging high resolution media (voice & video) interactively either with all participants or only with team members within a game environment. In this gaming use case, the control inputs are expected to be received by all game participants with an ability to maintain causality. Network offloading can utilise D2D when an opportunistic proximity offload potential exists. For example, a first device can initiate transfer of a media flow from the macro network to a proximity communications session with a second device, thereby conserving macro network resources while maintaining the quality of the user experience for the media session. Smart meters can use D2D communication among low capability MTC devices, for vehicular communication (for safety and non-safety purposes), and possibly also general M2M communication among different capability devices/machines. In the public safety regime, there can be either network-controlled D2D or a pure ad hoc D2D which does not utilise any network infrastructure for setting up or maintaining the D2D links. These are the two main categories of D2D networks, one taking place under control of a controlling (cellular) network and typically using licensed spectrum, and the other being ad hoc D2D which can work autonomously without network coverage.
In the cellular-controlled approach, the discovery communications, by which devices can discover each other's presence, are likely to be multiplexed with the (normal) cellular communications taking place on the same radio resources. However, it is important to ensure that these discovery communications do not interfere with or otherwise affect the operation of other devices using the cellular network with the (normal) cellular communications that conventionally take place, whether these other devices are also involved in D2D communications or not.
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In coronary and peripheral interventions requiring revascularization, many times a clot has formed proximal to the atherosclerotic lesion. Extraction of the clot prior to angioplasty or stenting can be preferred to reduce the possibility of distal emboli.
Systems available to physicians, including distal protection filters and mechanical clot maceration devices, are subject to limitations including difficult placement and manipulation, time to prepare and deliver devices, required occlusion of blood flow, and other complications such as arterial spasm and dissection. These devices in general are over-complicated and bring additional risks to the procedure. In addition, problems associated with the currently available thrombus extraction catheters include; kinking, buckling, stretching and ovaling. These problems all reduce the ability to quickly extract thrombus or navigate to the treatment site. The device of this invention solves these limitations by providing a means to quickly and directly remove the thrombus burden present in arterial and veinous interventions while maintaining the device mechanical integrity.
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1. Field of the Invention
The present invention relates to a spouted bed device, a polyolefin production system equipped with a spouted bed device, and a process for producing polyolefins such as polyethylene and polypropylene using such a device and system.
2. Related Background Art
A spouted bed has the advantage that all the particles, even relatively large particles several millimeters in size which require an excessively high gas velocity for fluidization in a fluidized bed, circulate and are thoroughly mixed. Various studies have been conducted on spouted bed devices of differing construction which utilize a spouted bed. As used herein, “spouted bed” refers to a state characterized by the circulatory movement of particles wherein, under the action of a gas introduced at a high velocity from a gas inlet orifice provided at the bottom end of a cylindrical vessel, there forms a spout (sometimes referred to below as the “spout portion”) which has a dilute particle concentration near the center axis of the particle bed held within the vessel and in which particles flow upward together with the gas, and there also forms at the periphery of the spout an annular particle bed where particles fall in a moving bed state under the influence of gravity (see, for example, Terminology Dictionary of Powder Technology, 2nd Edition, edited by The Society of Powder Technology, Japan (The Nikkan Kogyo Shimbun, 2000), p. 321).
However, to make a spouted bed device commercially feasible, it is important that a stable spouted bed be fully sustained even with some fluctuation in the treatment conditions. For example, if a fluctuation in the velocity of the gas being introduced or the amount of particles held inside the device causes the spouted bed to become unstable, resulting in particles dropping down through the gas inlet orifice, operation of the device must be interrupted to recover the particles.
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Active antenna arrays are increasingly required for sensors, communications, and electronic warfare systems. Active antenna arrays are arrays of antenna elements in which each antenna element or subset of antenna elements is driven by, or drives, one or more active radio-frequency (RF) device(s) such as a monolithic microwave integrated circuit (MMIC). Some prior art arrangements associate a transmit-receive (TR) module with each antenna element, as described in U.S. Pat. No. 5,017,927, issued May 21, 1991 in the name of Agrawal et al. or with a subset of antenna elements of the array, as described in U.S. Pat. No. 5,339,086, issued Aug. 16, 1994 in the name of DeLuca et al. Active array antennas are advantageous in that their beams can be steered instantaneously by simply adjusting the relative phase shifts of the signals to each antenna element or subset. They have the disadvantage, in general, of being expensive by comparison with antenna types such as reflector antennas.
At one time, the cost of the microwave monolithic integrated circuit (MMIC) was a major cost obstacle, and other costs, such as the TR module and antenna structure, were secondary. The art of making MMICs has improved, and their cost has decreased to a point at which the cost of the TR module structure and the antenna array structure have become important relative cost factors. Improved TR module arrangements for active antenna arrays are desired.
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Internet connectivity has become central to many daily activities. For example, millions of people in the United States use the internet for various bill pay and banking functionalities. Countless more people use the internet for shopping, entertainment, to obtain news, and for myriad other purposes. Moreover, many businesses rely on the internet for communicating with suppliers and customers, as well as providing a resource library for their employees. However, various entities still use the internet for malicious or non-reputable activity. For example, spammers send billions of messages daily causing headaches for many users and administrators.
Reputation systems and message profilers have enabled better recognition of non-reputable traffic. Reputation systems and message profilers can take a one size fits all approach to identifying non-reputable entities and/or messages. Such an approach can lead to users opting out of such protection and ignoring the information provided by such systems.
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Automobiles are equipped with bumpers, which are attached to either end thereof to absorb impact in a collision and limit as much as possible any damage to parts of the vehicle. In order to minimize damage to vehicles during low speed impacts, such as for instance less than about 15-16 km/h, car manufacturers provide “sacrificial elements” known as crash boxes, which in the event of impact cushions most of the impact energy, being deformed but preventing deformation of the vehicle chassis. In fact, any deformation of the vehicle chassis results in high repair costs, leading to unacceptably high insurance premiums, etc.
Typically, a bumper assembly with a sacrificial element comprises a pair of crash boxes, a cross member, a cushioning element such as foam or the like, and a bumper shield. In a prior art bumper assembly, the two crash boxes are fixed to the ends of two respective longitudinal members of the vehicle chassis via two respective plates. The cross member is joined to the opposite side of the crash boxes and extends continuously from one crash box to the other. The cushioning element made of foam or the like, typically, is constrained to the outside of the cross member. A bumper shield, having primarily aesthetic and aerodynamic functions, covers the bumper assembly.
Conventionally, both the crash boxes and the cross member are made of metallic materials, such as for instance steel or aluminum. The prior art solution, with metal crash boxes, cross members and plates for fixing the crash boxes to the vehicle, are considered to be somewhat awkward to assemble, heavy, costly and not easily adaptable to new vehicle models.
Accordingly, it would be advantageous to provide a crash management system that overcomes at least some of the above-mentioned limitations.
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The mutual comparison of two or more comparison targets can be implemented by utilising a data network. The comparison target may for example be a product, a service, a travel destination, a person etc. The purpose of the comparison is to produce a final result, on the basis of which a target can be presented to a person performing the comparison from several possible comparison targets, which target best corresponds to the needs and desires of the person performing the comparison with regards to the properties used in the comparison, which describe the comparison target. Said comparison system is generally called a comparator.
FIG. 1a shows a one-dimensional evaluation line 1 and an opinion/evaluation 2 presented by a user about an evaluation statement presented in connection with some property. In the example in FIG. 1a the left end of the line illustrates a situation, where the comparator user agrees with the presented statement regarding an examined property. The right end of FIG. 1a illustrates a situation, where the comparator user completely disagrees with the presented statement. The evaluation given by the comparator user regarding the presented statement can be compared to several different comparison targets. By proceeding thus it is possible to calculate a congruency between the evaluation given by the comparator user and each comparison target, which congruency can be called an accuracy percentage.
In addition to a one-dimensional evaluation line, the comparator can also utilise a two-dimensional fourfold. A single question fourfold of the comparator consists of two properties to be examined, which are set perpendicularly against each other in the displayed fourfold. The properties to be compared with the aid of the question fourfold are in some way related to each other. Each property is in the question fourfold described for example with numerical values 0-100%. Any values can naturally be selected as the numerical values of the end points, for example −10 and +10. Alternatively the properties to be compared can be described with word pairs, e.g. disagree agree, bad good or unimportant important.
FIG. 1b shows a principled model of a question fourfold 3 to be utilised in the comparator. The user of the question fourfold steplessly moves a response cursor 4 to a desired spot in the question fourfold 3. This stepless aiming possibility has been illustrated with four arrows pointing out from the cursor 4. When the response cursor 4 is according to the user in a spot, which corresponds to his opinion or evaluation with regards to the two properties shown in the fourfold, the user locks the response cursor 4 with a function related to the data processing device he uses.
In the examples in FIG. 1b the numerical value 0% of the horizontal axis of the fourfolds is situated in the left edge of the question fourfold and the numerical value 100% in the right edge of the question fourfold. Correspondingly the numerical value 0% of the vertical axis of the question fourfold is situated in the lower edge of the question fourfold and the numerical value 100% in the top edge of the question fourfold. What corresponds to a numerical value of 0% or 100% for each property is based on the definition made by the creator of the comparison procedure.
A person using the two-dimensional comparator sees two properties of the comparison target, one on the horizontal axis and one on the vertical axis. Generally the ends of the axes of the question fourfold describe opposite pairs of the same property. By using the two opposite pairs included in the question fourfold the comparator user can present his own evaluation of both examined properties by placing one evaluation point in a selected spot in the fourfold.
An example of a two-dimensional comparator is presented in U.S. Pat. No. 7,693,743. The patent presents a data collection and presentation method functioning in a data network, where a stepless two-dimensional data collection and presentation manner is utilised for collecting opinions and presenting the results of the inquiry. In the method according to the patent the operation is based on collecting evaluation data with the aid of a data network from persons selected by the person administrating the inquiry, the so-called inquiry creator, in two or more dimensions. The evaluation results of each evaluator are normalised per respondent, so that the average of the evaluation points of the evaluator entered into the fourfold is set in the origin and the deviation (standard deviation or some other value describing deviation) in a set standard value for each person performing the evaluation. With the described method the given responses can be scaled so that the evaluator's order of importance of different properties of the evaluation target are detected from the inquiry results, even if the responses given by some evaluator of the properties being evaluated were to be concentrated close together. Additionally the order of importance given to the properties by an individual evaluator can be scaled with the responses given by other participants in the inquiry. The scaled result can also be called a normalised result.
In the above-described examples the congruency of an evaluation given by a comparator user and one property of the target being evaluated can be expressed mathematically with the following expression:
A = [ 1 - X K - X E N ] * 100 , ( 1 ) in which N is an integer number, with which the axis of the question fourfold 3 (or the evaluation line 1) is divided into equally large parts (N is advantageously a number between 100 and 1000) XK is the value of the user's response point between 0 and N XE is the value of the response point of the target being evaluated between 0 and N and A is the congruency of an evluation given by the comparator user and the property of the target being evaluated expressed as an accuracy percentage for one axis of the question fourfold or evaluation line.
The total percentage S of the congruency of all evaluations given by the comparator user and all the properties of the target being evaluated is obtained with the equation:
S = ∑ j = 1 n A j n , ( 2 ) in which S is the congruency percentage of all the responses Aj is the congruency of axis jas an accuracy percentage and n is the total number of axes included in the utilised fourfolds and/or evaluation lines.
The comparator calculates the congruency of the evaluations of the comparator user and the properties of a certain comparison target using the equations (1) and (2). If necessary, the comparator calculates a corresponding congruency percentage illustrating the congruency for all comparison targets selected by the user.
A message-based online chat (Chat or LiveChat) implemented in a data network can also be utilised for comparing, marketing and selling articles and services. In the online chat a customer servant of the service provider and a possible buying customer engage in mutual text-based communication with the aid of their own data processing devices. The customer servant can with his own text-based messages guide the customer on the webpage by answering the questions posed by the customer or by posing his own specifying questions.
The online chat can be activated in many ways. There can for example be a button on the service provider's webpage, with which a customer on the webpage can invite a customer servant of the service provider to an online chat. Alternatively the customer servant can on his own offer online chat to a customer on the webpage. The decision about offering an online chat can be based on actions made by the customer on the service provider's webpage.
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1. Field
An embodiment of the present invention relates to the field of integrated circuit design and, more particularly, to the design of on-chip clock generation circuits.
2. Discussion of Related Art
Many modern integrated circuit devices, such as microprocessors, for example, use an on-chip phase locked loop (PLL) to synthesize a core clock signal. The core clock signal is then distributed across the device for use by various units. Such on-chip clock generation is advantageous in terms of hiding on-chip clock delays from external devices and in providing an efficient approach for clock frequency multiplication.
An example of a processor 100 including a prior on-chip clock generator unit 105 is shown in FIG. 1. At an input/output unit 110, an external clock signal 115 is received at a pin, for example, of the processor device 100. The external clock signal 115 is routed to an input of a PLL 120 in the clock generator unit 105. A PLL feedback clock signal 125 is also received by the PLL 120 to provide phase locked operation.
An output clock signal from the PLL 120 is buffered by one or more buffers 130 and provided as a core clock signal 135 through a clock distribution network 138 (only one signal line of which is shown) to various locations across the processor 100 including a bus clock generator 140. The bus clock generator 140 is provided to generate a clock signal for clocking external bus transactions. This clock signal may also be used as the PLL feedback clock signal 120.
The on-chip clock circuit of FIG. 1 may have some disadvantages, however, particularly when used on a large die, such as a microprocessor, in a high performance environment. The PLL feedback clock signal 120 is typically generated in the input/output area of a device. This input/output area is usually located near the periphery of a die for performance reasons.
The core clock signal 135 is delivered from the clock generator unit 105 to the input/output unit 110 by the above-mentioned clock distribution network including the signal line 138 shown in FIG. 1. Because the clock generator unit 105 provides the core clock signal to locations all over the processor 100, the clock generator unit is often located near the center of the die to facilitate distribution of the signal. Thus, particularly for a large die, the core clock signal 135 may traverse a relatively long distance across the processor 100, before reaching the bus clock generator 140.
As the core clock signal 135 is communicated from the clock generator unit 105 to the input/output unit 110 through various areas of the processor 100, such as the units 1 . . . n, the signal 135 is susceptible to localized power supply noise and signal cross-coupling in various regions. This noise is difficult to control due to the various activity and circuitry types across the processor 100 and may result in delay variation in the core clock signal 135 as it arrives at the bus clock generator 140. Because the PLL feedback clock signal 120 used to generate the core clock signal 135 is derived by the bus clock generator 140 from this core clock input signal 135, such delay variation may lead to clock jitter of the core clock signal 135.
Clock jitter can directly affect the overall performance of the processor 100 by effectively reducing the input/output (I/O) bus transaction rate. Because jitter results in a variation in clock edge placement, the bus transaction rate is reduced to account for this variation.
Other types of integrated circuit devices, such as digital signal processors, communications chips, cache memories, etc. that use on-die clock generators may present similar issues.
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1. Field of the Invention
The present invention relate to a two-input/one-output DC-DC converter and a power supplying system which is equipped with the same and which supplies power to a load from two DC power sources, and more particularly, a power supplying system for parallel feeding to a load from a fuel cell and from a secondary battery.
2. Description of the Related Art
Conventionally, a power source system for parallel feeding to a load is known which uses an independent power source, such as a solar cell or a fuel cell, and a secondary battery (see, for example, JP 2003-134691A). According to this power source system, three boost converters are provided between the fuel cell and the secondary battery, power is supplied to the load from the fuel cell through a first boost converter, and excess power of the fuel cell is stored in the secondary battery through the second boost converter. Moreover, power is supplied to the load from the secondary battery through the third boost converter to make up the shortage of supplied power from the fuel cell.
Regarding fuel cell electric vehicles, there is known a power supplying system which adjusts a voltage through a DC-DC converter capable of both boosting and bucking and which connects a low-voltage system of 12 V including vehicle accessories and a low-voltage battery, and, a high-voltage system of 350 V including fuel-cell accessories and a load together (see, for example, Japan Patent No. 3744456). According to this power supplying system, a connection is established in such a way that an output voltage by the fuel cell is directly applied to the load.
In the technical field of fuel cells, there is a technological challenge for reducing the number of cells in a stack of a fuel cell from the standpoint of cost reduction and of a spatial restriction. When the number of cells in the stack is reduced, the output voltage by the fuel cell is decreased, so that if, like Japan Patent No. 3744456, an output voltage by a fuel cell is directly applied to a load, the load cannot acquire necessary motor output power. Conventionally, there is also known a system which further has a heavy-electricity booster at the output side of a fuel cell in addition to the configuration of the power supplying system disclosed in Japan Patent No. 3744456, and which supplies power to a load through the high power booster (see, for example, Japan Patent No. 3709789). This system also has a secondary battery capable of being charged by the high power booster, and the secondary battery can supply power to the fuel-cell accessories and to the load.
According to the systems disclosed in JP2003-134691A and in Japan Patent No. 3744456, however, when a fluctuation range of a voltage of a fuel cell is large or when a battery voltage reduction occurs, it is difficult to stably supply power to individual system elements. Moreover, according to the system disclosed in Japan Patent No. 3709789, when the voltage of the fuel cell or the voltage of a battery (the secondary battery or the low-voltage battery) fluctuates, it becomes difficult to supply power to the fuel cell accessories and to the load at a stable voltage.
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1. Field of the Invention
The invention relates to a piston pump for a vehicle brake system, having a housing section and a piston that is guided displaceably in the housing section, a receiving element for receiving an inlet valve, a sealing element adjoining the receiving element for sealing off the piston from the housing section, and a piston rod adjoining the sealing element.
2. Description of the Prior Art
The piston pumps for known vehicle brake systems, in particular anti-lock systems (ABS), serve to control the pressure in wheel brake cylinders. In the ABS, the piston pumps are intended for instance for returning brake fluid from one or more wheel brake cylinders to a master cylinder. Often, the ABS functions in combination with traction control (TC). Another known system, the electronic stability program (ESP), improves driving safety by a further increment compared to ABS and TC. While ABS and TC act in the longitudinal travel direction, ESP affects the transverse dynamics and in principle is therefore transverse traction control. For all these systems and for other systems for increasing driving safety, piston pumps are used.
Known piston pumps intended for vehicle brake systems comprise among other things a cylinder, which is embodied in a housing and in which a piston is received longitudinally movably. The piston drive is usually effected by an eccentric drive, in which the rotary motion of a shaft driven by a drive motor is converted to a translational motion of the piston. In the process, the piston rod is pressed with its face end against the outer circumference of the eccentric element of the eccentric drive by a prestressing element, for instance in the form of a helical spring. Thus in the final analysis, a reciprocating pumping motion of the piston can be attained.
Moreover, known piston pumps, to control the fluid inflow, have an inlet valve embodied as a seat valve; in the cylinder, between the inlet valve and the piston, a sealing element is also provided, which is guided longitudinally movably in the cylinder. The piston of known piston pumps is mounted with its face end, disposed inside the cylinder, on the sealing element, so that a reciprocating piston motion is transmitted directly to the sealing element. On the end of the sealing element toward the inlet valve, a valve seat of the inlet valve embodied as a seat valve is embodied, and for the fluid inflow, a bore extending through the sealing element is provided, which extends as far as the valve seat, so that fluid flows through the inlet valve that is open in the intake phase. The barrier body of the inlet valve embodied as a seat valve is pressed via a spring element against the valve seat embodied on the sealing element, and the barrier body, the spring element, and the end, embodied as a valve seat, of the sealing element are received in a receiving element in the form of an inlet valve cap. The inlet valve cap serves as a brace for the spring element and as a guide for the barrier body. Around the inlet valve cap, there is a prestressing element in the form of a helical spring, which presses against a bracing body embodied on the inlet valve cap that is received in a recess embodied in the sealing element, in order to transmit the spring force, transmitted to the bracing body, to the piston mounted on the sealing element by way of the sealing element. In this way, prestressing can in the final analysis be transmitted to the piston, in order to press the piston against the eccentric element of the eccentric drive.
Thus viewed overall, many pump components are disposed in the cylinder of known piston pumps. As a consequence, assembling and disassembling know piston pumps is comparatively complex. Moreover, because of the many pump components provided, known piston pumps cannot be manufactured especially economically.
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1. Field of the Invention
This invention relates to heated animal surgery tables.
2. Description of the Related Art
Animal surgery tables are well known in the prior art. The upper, or supporting surface, of animal surgery tables is typically stainless steel, which can be cleaned and sterilized easier than most surfaces. Accordingly, they are well suited to use during surgery.
Although widely used, such tables present a significant problem in use. Stainless steel is a good conductor of heat and consequently draws body heat out of the animal during surgery. Studies demonstrate that the resulting heat loss typically drops the animal's body temperature by about 2.degree. F. (1.11.degree. C.). When an animal's body temperature drops, its heart rate increases, increasing the loss of blood and the general stress on the animal. This thermal loss can result in hypothermia, increases the trauma and stress on the animal, increases the mortality rate from surgery and from certain types of illness or injury, increases recovery time and reduces metabolism.
Rags are sometimes wrapped around the animal to reduce the heat loss, but the practice is largely ineffective for this purpose. The practice is also unsanitary and can interfar with the surgery.
Accordingly, there is a need for an animal surgery table that does not draw heat away from the animal during surgery.
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The invention relates generally to semiconductor and component packaging technology and in particular to a method and apparatus for providing line terminating networks for a semiconductor chip package.
In a typical printed wiring board configuration, a mounting socket is electrically connected, permanently, for example by wave soldering, to the printed wiring board, and a semiconductor package is inserted into the socket. Discrete components are connected between the printed wiring board socket connections and, for example, termination potentials required by the semiconductor chip for proper operation. As the number of terminals on the semiconductor chip package grows, the available space on the printed wiring board becomes increasingly crowded and, for example, it may occur that fewer semiconductor packages can be mounted on a board because of the number of discrete components required therefor.
One solution to this problem is to employ planar technologies to produce planar components within the printed wiring board itself, for example the many termination resistors required by the semiconductor package. This solution to the component crowding problem is expensive, however, because of the large number of initially rejected boards which have one or more bad parts embedded therein. As a result, the manufacturing process of employing planar technology in the printed wiring board requires several additional quality control and rework process steps to ensure that a large board, which may contain as many as, for example, five thousand planar termination resistors, is acceptable.
Furthermore, when dealing with high density ECL technology, the number of routing channels, normally two for other semiconductor technologies, increases to three, and further, ECL technology requires that the routing channel connection be made first to the terminal of the semiconductor socket and then to the terminating component. There results therefore a severe congestion in the printed wiring board.
Primary objects of the invention, therefore, are to alleviate the component crowding on a printed wiring board and to provide faster, more reliable circuitry, and to connect semiconductor packages to a printed wiring board in a manner which is less expensive than that previously known. Other objects of the invention are to increase the density of semiconductor functions on a printed wiring board, thereby increasing the compactness and speed of the circuitry.
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1. Field of the Invention
The present invention relates to a system and method for custom fitting athletic shoes to wearers by measuring the feet, correlating the foot measurements to settings on an adjustable last, fitting an appropriately sized shoe with heat malleable activation zones on the adjustable last and heat-treating the shoe while adjusting the last to customize the fit of the shoe to the wearer.
2. Background of the Invention
The athletic shoe industry continues to research ways to improve the fit of athletic shoes, and to customize the fit to an individual wearer. The oldest way of custom fitting shoes to an individual wearer is to make the shoes based on a customized last for the particular individual's feet. This is tantamount to custom tailored or bespoke clothing, and involves an expensive and time consuming process. Numerous attempts have been made to try to bring a custom fit to the mass produced market for footwear.
One of the obstacles to customizing the fit of mass produced shoes in the past has been the fact that the component which has the primary influence on fit, the shape of the last on which the footwear is formed, has remained unchanged. In general a last or form is made by taking the following foot measurements into account: the overall length of the foot, the width of the foot, the height of the first digit, the contour of the instep, and at least six girth measurements. The general practice is to shape a last for mass production by utilizing foot measurements from a broad spectrum of the population to determine the characteristics of a statistically average foot. This will theoretically achieve a proper fit for a majority of the population. Footwear sizing is generally based on the overall length of a wearer's foot with accommodation made for the width or girth of the foot. Most footwear manufacturers only provide consumers with footwear in limited length-width combinations.
Prohibitive manufacturing and retail inventory challenges prevent mass manufacturers and marketers from offering footwear sizes in a full spectrum of length-width combinations. Since each length-width combination for an article of footwear generally requires a unique last that is correctly proportioned for that particular length-width combination, economics generally forces manufacturers and retailers to offer a limited spectrum of length-width combinations, based again, on a statistically average foot. The attempt is to cover as large a cross section of the population as possible. Research has demonstrated that this approach, while cost effective, has drawbacks to the consumer. Traditionally manufacturers use the same tooling for different widths, only the upper is differently sized in width.
Many individuals do not have feet with statistically average proportions so the usual length-width combinations would not provide a proper fit. Some people have feet of left and right feet of different widths, such as the dominant foot being slightly larger. Any of these factors necessitate fit adjustment to enable the wearer to receive the full benefit of an athletic shoe in particular.
One way of providing a custom fit is described in commonly assigned U.S. application Ser. No. 10/099,685 filed on Mar. 14, 2002, which is hereby incorporated by reference. The '685 application describes a method by which a wearer can purchase footwear through a remote communication channel by specifying the last that is used to construct the footwear. The wearer can identify a last based on previous experience with footwear that was constructed using that last. The last may be specified by a model number and size, or by employing measurements of the wearer's foot to determine the last which is used to construct the footwear.
Shoes have been made with a variety of adjustment mechanisms such as fastening systems, differing materials and the like, but mass produced shoes generally are still made with predetermined lasts or forms. Little has been done to customize the fit of mass produced shoes by adjusting the lasts themselves. Since the shoe is completed during manufacturing, even if any adjustments were made in the past, they would have to be performed during manufacture, thus delaying greatly the receipt of customized shoes by the wearer.
Prior attempts to customize the fit of athletic shoes have resulted in many solutions which all require the wearer to wait for the customized shoes. There exists a need for a retailer to provide a customized fit after manufacture of the shoe, preferably at the point of sale.
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The present invention is directed, in general, to a method of fabricating a semiconductor device and, more specifically, to a semiconductor device having multilevel interconnections and a method of manufacture thereof.
The semiconductor industry is currently moving toward low dielectric constant (low-k) materials and copper metal to form interconnections for semiconductor devices to reduce resistive capacitance delays associated with the higher dielectric constant of silicon dioxide. These low-k materials also are used to reduce RC delays of aluminum interconnections and higher densities of a is conductor per unit are of the device. Furthermore, industry is presently moving away from metal etching of conductor lines followed by gap-fill with a low-k dielectric because copper metal is difficult to etch. In place of these processes, the industry has adopted damascene strategies for fabricating these interconnections that first etch patterns into the low-k material and then fills the structures with metal. Damascene processing has fewer manufacturing steps per completed metal layer, and considering that devices of the near future will require as many as seven inter-level connections, such as vias, and a corresponding number of intra-level connections, such as wires or lines, damascene processing should lead to considerable cost and performance gains over traditional interconnect processing. Additionally, dual damascene strategies where both the via and wire are patterned simultaneously etched and simultaneously filled with metal, further reducing the number of processing steps.
These damascene processes are not without their problems, however. Some of those problems arise with respect to the use of hard masks and critical dimension control. In the damascene approach as line widths shrink, it has become increasingly difficult to apply a copper seed layer to allow a complete fill by electroplating processes. Furthermore, during etching of the damascene structures, the selectivity of etching low-k materials, which are frequently polymeric materials, in the presence of photoresist is poor and requires inorganic dielectric etch stops to allow for over-etching and resist strip. During etching, there is a danger of undercutting the hard mask forming an area that is difficult to completely cover in subsequent deposition processes, resulting in a void. Thus, deposition of barriers to prevent copper diffusion and deposition of copper seed for electroplating are difficult processing steps, particularly given the high aspect ratios associated with today""s submicron technologies that are less than 0.25 xcexcm. Because of these high aspect ratios, the step coverage of severe topography is frequently insufficient and results in incomplete coverage of the feature sidewalls and bottom that leads to thin or missing barrier material and copper seed resulting in barrier failure or void formation during plating. Also, void-free fill of metal by electroplating is difficult since plating tends to cover topography conformally leading to a seam in the center of the feature. This can form a region of high electromigration probability that reduces device reliability. Additionally, the seam-void can also act as a trap for liquid plating solution that can xe2x80x9cexplodexe2x80x9d during subsequent processing steps that achieve temperatures above the boiling point of the trapped liquid. Since plating tends to occur conformally, areas with a high density of small features tend to fill faster than larger open areas. As a result metal, must be plated to a thickness at least as the depth of the largest feature. This forms topography of varying heights that are difficult to planarize with chemical mechanical polishing (CMP) processes.
Accordingly, what is needed in the art is a method and resulting device that avoid the problems associated with the above-discussed processes.
To address the above-discussed deficiencies of the prior art, the present invention provides, in one aspect, a method for fabricating an interconnect system within a semiconductor device. In this particular embodiment, the method comprises forming a conductive layer over a substrate of the semiconductor device, such as a dielectric material, forming a photoresist layer over the conductive layer and patterning the photoresist, forming a selected portion and an unselected portion of the conductive layer, altering the selected portion such that the selected portion has an etch rate different from an etch rate of the unselected portion, and forming an interconnect on the selected or unselected portion. As used herein, the selected portion is defined as that portion of the conductive layer, such as a blanket seed layer, that is subject to the alteration process as discussed herein. The selected portion may be, depending on the embodiment, within a footprint of the interconnect or outside the footprint of the interconnect. The interconnect structure formed by the present invention includes interconnect lines, contact plugs or metal filled interconnect vias.
Thus in a broad scope, the present invention provides a method of uniformly forming a conductive layer on which an interconnect is formed within a patterned photoresist. Because of the uniformity with which the conductive layer is formed and its presence only at the bottom of the pattern, problems, such as the occurrence of voids within the interconnect, that arise due to conformal plating of aspect ratios associated with present day and future submicron technologies can be avoided, thereby, providing a more reliable interconnect within a semiconductor device. Moreover, the present invention eliminates the need for critical etches and highly conformal seed for electroplating.
In one embodiment, forming an interconnect on the selected portion includes forming an interconnect on the selected portion and the method further comprises removing a substantial portion of the unselected portion from a region around the interconnect. The term xe2x80x9csubstantialxe2x80x9d as used herein is used to account for unintentional trace amounts that might remain due to inefficiencies in the removal process. In this embodiment, the selected portion is subjected to the alteration process wherein its etch rate is altered to have an etch rate less than an etch rate of the unselected portion. Thus, the unselected portion is more easily removed by the etching process.
In another embodiment, forming an interconnect includes forming an interconnect on the unselected portion and the method further comprises removing a substantial portion of the selected portion from a region around and outside of the interconnect""s footprint. In this embodiment, the selected portion is subjected to the alteration process wherein its etch rate is altered to have an etch rate greater than an etch rate of the unselected portion. Thus, the selected portion is more easily removed by the etching process.
Various processes may be used to alter the selected portions of the conductive layer. For example, the process may include subjecting the selected portion to an ion bombardment process, or, the process may include subjecting the selected portion to a nitridation, oxidation or halogenation processes. Alternatively, altering may include alloying and forming compositions of the selected portion with another metal from Groups IIA-VA or a transition metal or a lanthanide metal. Compositions of the selected portion and the interconnect metal are particularly advantageous. In such embodiments, the interconnect metal and the conductive layer should be chosen so that they will interdiffuse or alloy under the desired processing conditions. For example, the conductive layer metal may be Group II metals, such as magnesium, or antimony. Other exemplary conductive layer metals may include titanium, zirconium, zinc, tin, lead, niobium, chromium, molybdenum europium, tungsten, palladium, or aluminum when the metal used to form the interconnect is copper or silver. Yet other metals may include Group VA metals, such as antimony, transition metals, such as tungsten or lanthanide metals, such as neodymium. In yet another aspect of this particular embodiment, forming an alloy may also include forming a diffusion barrier to prevent interconnect metal from diffusing into materials that contact the interconnect.
Altering may also include interdiffusing the selected portion and the interconnect. Preferably, the interdiffusion forms a barrier layer between the interconnect and surrounding dielectric.
In another embodiment, the method further comprises removing the photoresist and the unselected portion outside a footprint of the interconnect and forming a dielectric layer over the interconnect subsequent to removing the photoresist and the unselected portion outside the footprint. The dielectric layer may be deposited by a vapor or liquid and may be comprised of a homogeneous or heterogeneous composition. In another embodiment, forming and patterning the photoresist layer includes forming a seed layer that comprises the metal used to form the interconnect by a directional deposition process.
In those embodiments where the interconnect is formed on a dielectric material, forming the conductive layer includes forming the conductive layer in such a way as to form a barrier layer between the interconnect and the substrate.
The present invention provides yet another unique aspect of forming an interconnect. In this particular embodiment, forming an interconnect includes forming a suspended, multilevel interconnect that is preferably formed on a single conductive layer. This particular embodiment may further include forming a barrier layer between the interconnect and the substrate. In one aspect of this particular advantageous embodiment, forming the suspended interconnect includes forming and patterning a subsequent photoresist layer on the interconnect, forming a subsequent interconnect pattern on or in the subsequent photoresist layer such that the subsequent interconnect physically contacts the interconnect. After the formation of the interconnect, the photoresist and the subsequent photoresist are simultaneously removed. In another aspect, the method further comprises simultaneously forming with the suspended interconnect, a support structure for the suspended interconnect.
In another aspect, the present invention provides a method for fabricating a semiconductor device, on a semiconductor wafer. In this particular embodiment, the method includes forming a dielectric layer over an active device formed on the semiconductor wafer, forming a blanket conductive seed layer over the dielectric layer, forming a photoresist layer over the conductive seed layer and patterning the photoresist, forming a selected portion and an unselected portion of the conductive seed layer, altering the selected portion such that the selected portion has an etch rate different from an etch rate of the unselected portion, and forming an interconnect on the selected or unselected portion.
Another embodiment is directed to a semiconductor device that includes an active device region, a blanket, conductive layer formed over the active device region, and a suspended interconnect formed on the conductive layer as is discussed below. In this particular embodiment, the device further includes a suspended interconnect support structure, such as a bond pad, that is electrically connected to the suspended interconnect. This embodiment may further include a plurality of electrically connected interconnect lines, contact plugs, or metal filled vias formed on different levels of the semiconductor device. The various levels of interconnect structure may be electrically isolated by a gaseous dielectric, such as a rare gas, nitrogen, forming gas, sulfur hexafluoride, or vacuum, in place of conventional dielectric materials. Preferably, the dielectric has a dielectric constant of less than about 2.3.
The foregoing has outlined, rather broadly, preferred and alternative features of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form. dr
For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 illustrates a schematic sectional view of an active device having a uniform blanket conductive layer and a photoresist formed thereon;
FIG. 2 illustrates an enlarged sectional view of a top section of FIG. 1 showing a selected portion of the conductive layer;
FIG. 3 illustrates the selected portion of FIG. 2 following plating that contacts the underlying metal through the blanket conductive layer;
FIG. 4 illustrates the interconnect of FIG. 3 after the removal of the photoresist;
FIG. 5 illustrates the interconnect of FIG. 4 after the removal of the portion of the conductive layer outside the footprint of the interconnect metal;
FIG. 6 illustrates a barrier layer formed over the interconnect of FIG. 5;
FIG. 7 illustrates the barrier layer and interconnect of FIG. 6 after a directional sputter/etch;
FIG. 8 illustrates the barrier layer and interconnect of FIG. 7 after the deposition and planarization of an intra metal dielectric;
FIG. 9 illustrates the structure of FIG. 8 after the deposition of a subsequent conductive layer;
FIG. 10A illustrates the structure of FIG. 9 after depositing and patterning a subsequent layer of photoresist and altering the selected portion;
FIG. 10B illustrates the structure of FIG. 10A after formation of a subsequent interconnect ion metal, removal of photoresist and removal of the conductive layer outside the footprint of the interconnect metal;
FIG. 11A illustrates a sectional view of a suspended interconnect structure;
FIGS. 11B-11E illustrate sectional views of various intermediate steps during the formation of the suspended interconnect structure of FIG. 11A;
FIG. 12 illustrates a flow chart for process forming multilevel suspended interconnect structures;
FIG. 13 illustrates a flow chart for process forming multi levels with intra metal dielectric one layer at a time.
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It is particularly preferred to employ Staphylococcal genes and gene products as targets for the development of antibiotics. The Staphylococci make up a medically important genera of microbes. They are known to produce two types of disease, invasive and toxigenic. Invasive infections are characterized generally by abscess formation effecting both skin surfaces and deep tissues. S. aureus is the second leading cause of bacteremia in cancer patients. Osteomyelitis, septic arthritis, septic thrombophlebitis and acute bacterial endocarditis are also relatively common. There are at least three clinical conditions resulting from the toxigenic properties of Staphylococci. The manifestation of these diseases result from the actions of exotoxins as opposed to tissue invasion and bacteremia. These conditions include: Staphylococcal food poisoning, scalded skin syndrome and toxic shock syndrome.
A Blast P search result of publicly available sequence data, using the amino acid sequence of the invention as a query sequence, revealed a Streptococcus mutans homologue, which is a GTP-binding protein (ERA, sp/P42182/BEX_BACSU BEX PROTEIN).
Clearly, there is a need for factors that may be used to screen compounds for antibiotic activity, such as novel ERA of the invention. These factors may also be used to determine their roles in pathogenesis of infection, dysfunction and disease. There is a further need for identification and characterization of such factors and their antagonists and agonists which can play a role in preventing, ameliorating or correcting infections, dysfunctions or diseases.
The polypeptides of the invention have amino acid sequence homology to a known Streptococcus mutans GTP-binding protein ERA protein.
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Wire saw cutting is widely used in slicing semiconducting crystals, such as silicon ingot, gallium arsenide (GaAs), gallium phosphide (GaP), and the like to produce wafers for making electronic and photovoltaic devices. The wire saw slicing works through abrasive grinding action provided by an abrasive slurry consisting of a cutting fluid and abrasive particles, generally of silicon carbide (SiC), suspended in the fluid. The cutting fluid plays a critical role in achieving efficient and precise slicing by (i) suspending and carrying abrasive particles and swarf (i.e., semiconductor crystal chips produced the cutting of the crystal), (ii) lubricating the workpiece, and (iii) removing the frictional heat generated at the cutting site.
Polyalkylene glycols (PAG), in particular polyethylene glycols (PEG), are commonly used as semiconductor crystal cutting fluids. The demand for semiconductor wafers continues to grow, especially in the photovoltaic market, and with it a demand for a more cost-effective production of silicon wafers. The cost and quality of silicon wafer production can be improved by boosting cutting speed, increasing wafer yield, reducing total thickness variation (TTV) of wafers, reducing saw marks and warp, decreasing wafer thickness, and prolonging the lifetime of cutting wires. All these improvements require higher performance cutting fluids that can more effectively disperse the abrasive, e.g., SiC particles, and crystal, e.g., silicon, swarf particles.
One known solution is to add a dispersant, such as polyelectrolyte, to the PAG to produce formulated PAG-based cutting fluids. However, this additional formulation step increases the complexity and cost of the cutting fluid production. The invention is to produce PAG materials as cutting fluids with improved dispersing ability for SiC and Si particles but does not need the additional step of adding dispersants.
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1. Field of the Invention
The present invention relates generally to devices and methods used to detect defects in isolation and insulation in electrical wiring. More specifically, the present invention relates to devices and methods that detect defects in a specialized test gas environment.
2. Description of Related Art
Wires or cables typically have a conductor made from conductive material. Characteristically, conductive material is a class of material incapable of supporting electric stress, such that when a charge is given to a conductive material it spreads to all parts of the material. Exemplary conductive materials include aluminum, copper, platinum, gold, silver, chromium, tungsten, nickel, combinations thereof, and the like.
The conductors of wires are commonly coated with a solid insulating material primarily to provide electrical isolation between wires. In addition to its primary function, the solid insulation material also helps provide thermal insulation, strain relief, protection against mechanical damage and abrasion, chemical and corrosion protection, sealing, and limit signal distortion. The thickness and dielectric characteristics of this solid insulation are specifically chosen to maintain isolation, limit shock danger and signal distortion seen in the conductor. As wire is used for a wide variety of purposes, there are differences in the type of insulation used. For example, a data communication cable may use a Teflon(copyright) FEP coat to promote transmission and provide physical protection.
Occasionally the solid insulation surrounding conductive wires is damaged or defective. The damaged or defective solid insulation may expose the conductors. The damage or defects in the insulation may be very small and difficult to see. Defects, such as cracking, often results from mechanical stresses imposed upon conductors having brittle insulation. Embrittlement of the insulation is a result of the normal aging of the insulation. Aging is often accelerated by cable operation at high temperatures over an extended period of time. Mechanical stresses may be caused by short-circuit currents, thermal expansion and contraction of the conductors, movement of the conductor, and vibration. While the dielectric strength of insulation is not significantly reduced by brittleness alone, loss of isolation can result from the development of cracks. For this reason, close inspection of insulation should be made at frequent intervals, and repairs made as necessary.
More specifically, it is important to know if insulating material surrounding a conductive wire or cable has been pierced or broken. Such a defect could be a precursor to an electrical failure in the overall electrical system in which the wire or cable is installed. Similarly, isolated conductors, which are too close together, such as exposed pins in a connector or conductors in an automobile fuse box, may cause an electrical short circuit. Bent or damaged conductors may violate the air gap distances necessary to maintain isolation, thereby introducing a potential short circuit or flashover situation within the electrical system. Failures in the solid wire insulation or uncontrolled short-circuiting between exposed conductors have caused numerous accidents in aircraft and other vehicles. It is therefore desirable to find damaged insulation and verify conductor isolation before a failure occurs so that appropriate repairs can be made.
Unfortunately, the defect and fault detection methods presently available are counterproductive to the defect detection process. For example, high voltage is commonly used to find defects in solid insulation, but the voltage required to find these insulation defects is often higher than the voltage rating of the insulation. Thus the test itself can actually destroy or weaken the insulation and wiring being analyzed, thereby creating defects in the solid insulation. What is needed is a method of reducing the voltage required to detect defects and electrical isolation faults in the electrical pathways.
Furthermore, traditional high voltage testing methods may not be used for wiring located in fuel rich operational environments, such as near jet engines. Applying a high voltage in such an environment creates a substantial risk of combustion unless all of the fuel is removed prior to testing. Some testing methods, such as introducing an ion cloud without displacing the oxygen, actually increase the risk of a spark igniting the fuel.
Accordingly, what is needed is an improved technique for testing insulation and isolation defects in electrical wiring. In particular, the test should not compromise the integrity of the wiring being tested nor be the cause of additional damage to the wiring. Additionally, a method of testing wiring for defects in unstable environments, such as a fuel rich jet engine environment, without generating a substantial risk of combustion is needed.
The present invention provides a system and method of detecting breaches in solid insulation and detecting insufficient air gaps between conductors. The invention performs these detections in a specialized gas environment tailored for high voltage defect sensor applications. The present invention has been developed in response to the current state of the art, and in particular, in response to these and other problems and needs that have not been fully or completely solved by currently available sensor or electronic detection applications. The present invention reduces the amount of high voltage required to detect an insulation or isolation defect when performing a high-voltage breakdown test. These qualities are primarily accomplished through injection of a test gas into the area around the electrical pathway or conductor being tested. Exemplary test gases useful with the present invention include neon, helium, argon, xenon, krypton, radon, and combinations thereof. Helium, for example, has been shown to require a lower voltage gradient than air requires (e.g., at 1500 V and at atmospheric pressure, an arc occurs at approximately 0.009 short-inch in air versus 0.4 inch in helium), and is an excellent choice for the test gas.
The lower voltage gradient of an easily ionized test gas when compared to ambient air helps the system check the solid insulation around wires and cables at a lower voltage potential. The test gas is directed or confined such that it envelops the area to be tested. When high voltage is applied between conductors that are exposed and physically close, a corona forms or an arc occurs between the conductors through the test gas. A testing device may record electrical noise or a current surge between the conductors. Prior to arcing, the added test gas exhibits a very high electrical resistance. Once a sufficient voltage gradient is applied, the test gas xe2x80x9cbreaks downxe2x80x9d or ionizes and has very low effective resistance. With the lower resistance it is easier for an electrical arc to form between the conductors. In an effort to promote this effect at a lower voltage, the voltage gradient for the breakdown of the test gas used in the present invention is substantially lower than for ambient air.
Several configurations are available to test the electrical isolation of the cables in a gas-enriched test environment. One configuration uses a gas-containment shroud to maintain the gas enriched test environment. The gas containment shroud may be flexible and conform to the curvature of the electrical cables. The gas containment shroud may also be transparent, thereby making visible any corona activity around the electrical cables.
A high voltage breakdown tester places sufficient voltage potential across the conductors to detect insufficient isolation or defective insulation. An alternative configuration introduces at least one conductive probe into the shroud environment. The probe is connected to a tester and moved along the conductors. A defect in the insulation is detected when current flow is detected because of an arc between the probe and the conductors being tested. The arc occurs at the location of a defect in the isolation or insulation of a conductor, specifically where the voltage potential between the probe and the exposed conductor overcomes the voltage gradient required for electrical breakdown of the test gas. The application of the test gas by a gas source to a localized region of the conductors enclosed by the gas containment shroud may also be synchronized with a current-sense module on the high voltage breakdown tester to locate an isolation or insulation fault.
Using the characteristics of the test gas, the present invention may also verify the air gaps or required distance between isolated conductors separated by air. Exemplary air gaps include the pins in a connector or exposed conductors in an automobile fuse box. In the present invention, when a pin in a connector is bent, the applied voltage will promote arcing between the closest pins alerting a monitoring test device of the potential short circuit between wires.
Additionally, the system may also be used in fuel rich environments with a substantially lower risk of explosion. As the injected test gas displaces oxygen in the testing area, less oxygen is available for combustion. At certain concentrations of gas there is insufficient oxygen for combustion to occur. The concentration of the test gas in the testing area may be controlled in part by a gas containment shroud, which restricts the movement of the test gas away from the testing area.
The present invention reduces the amount of high voltage required to detect an insulation or isolation defect. The present invention detects the location of insulation defects without damaging the conductor being tested. The present invention allows the safe application of a high-voltage breakdown test for air gaps and insulation defects in fuel rich environments. The present invention enhances the sensitivity of a high-voltage breakdown test with respect to air gaps between conductors in a localized region. As such, the present invention helps verify the required distance between isolated conductors separated by ambient air, such as the pins in a connector or exposed conductors in an automobile fuse box.
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An increase in memory density results in inexpensive, high capacity storage. By 2020, it is expected that a memory device can store a trillion bits of information in an area the size of a postage stamp. However, increasing the density in memory is becoming ever more complex and expensive. And, with current conventional technologies the increment increase in memory density is slowing due to the difficulty of scaling, perhaps not even keeping pace with Moore's law.
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This application claims a priority from German Patent Application No. 100 36 703.8, filed Jul. 27, 2000, and the contents of the application are incorporated herein by reference.
This invention concerns a process and an apparatus for the correction of resamplers.
Resamplers, that is sampling-rate converters are used to convert a sampled digital input signal having one input sampling rate into a sampled digital output signal with a different output sampling rate. With a process of this invention there is an input signal having a sampling rate, or frequency, which is larger by an arbitrary factor (not necessarily by a whole number, or integer) than a symbol frequency or a chip frequency. With a Wideband Code Division Multiple Access (WCDMA) signal, every data symbol in a chip sequence is coded so that each symbol is of a plurality of chips. A binary change between two amplitude values can take place between the chips. The invention, however, is also suitable for other digital signals with then the term “chip frequency” being replaced by the term “symbol frequency” or “symbol rate”. Upon translating the input sampling rate into the symbol or chip frequency, the problem arises that the relationship between the input sampling rate and the symbol or chip frequency is only approximately known, since a timing generator of the resampler is not identical with a timing generator of the input sampling rate, and thus a drift between the two oscillators is possible. Further, an absolute phase position of the input sampling rate is unknown.
It is therefore an object of this invention to provide a process and an apparatus for the correction of a resampler with which a sampled input signal, which is subjected to an input sampling rate and which has a symbol or chip frequency that differs from that of the input sampling rate, is translated into a sampled output signal in which a sampling rate corresponds to the symbol or chip frequency by changing the input sampling rate by a resampling factor, with which a drift between the input sampling rate and the symbol or the chip frequency as well as an absolute, constant shifting of the phase of the input sampling rate are compensated.
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The present invention relates to a magnetic recording medium such as a magnetic disk including a substrate. Information can be read out by a magnetic head from the surface of the medium. More specifically, the present invention relates to a magnetic record medium having an information recording density improved by minimizing the distance between the magnetic recording medium and the magnetic head.
The information recording density of magnetic disk devices has recently been increasing by as much as 60% every year. Effective approaches to increase the recording density include those intended to improve the characteristics of the magnetic recording medium or the head, the most effective one being to decrease the distance between the magnetic recording medium and the magnetic head while information is being read from or written on the medium.
When the magnetic recording medium is stopped, the head is held on a surface of the magnetic recording medium through contact with a region called a contact start stop (CSS)region. When a read/write instruction is provided to the magnetic disk unit, the disk unit rotates the recording medium and makes the head float above the recording medium. To reduce friction between the surface of the recording medium and the head, the surface of the substrate of the recording medium is embossed to provide favorable roughness, which is referred to as texture.
To fabricate the texture, if the recording medium has a low recording density, a method known as "scratch texture" is employed in which whetstone grain is used to scratch the substrate surface. As the demand for high-density recording medium increases, machining methods with higher precision are required. One such method is known as "laser texturing". This method uses laser light and can minimize the distance between the substrate and the magnetic head.
Conventionally, the laser texturing method has been primarily intended to form a texture in the CSS region but not in the data region, which serves as an information storage region in the recording medium. In this approach, the surface of the data region is made as flat as possible so that the distance between the substrate and the magnetic head is further reduced and a high recording density is achieved.
When the head is moved to a data region having no texture formed thereon, the flying characteristics of the head may be affected. This may result in the head colliding with the substrate in a seek operation, in which the head is moved to a desired position. Further, a protective film formed on the surface of the magnetic head or the recording medium may be damaged by the shock of the collision, which reduces the life of the magnetic disk device.
In addition, the head may collect lubricating agents, which are uniformly applied on the protective film. This lowers the friction characteristic of the magnetic head after the head is stopped in the CCS region. The lubricating agents that have been deposited on the head increase the static friction applied when the substrate starts to rotate. This leads to immobilization (sticktion) of the head on the substrate, and the substrate cannot be rotated.
The problem above is also influenced by the operational environment of the magnetic disk. Therefore, failure in the seek operation should be prevented so that the influence of the operational environment is eliminated as much as possible.
Accordingly, a method to fabricate the texture over the entire surface of the substrate has been proposed, which addresses the failure in seek operations. A method known as thin film texturing is used for a recording medium having a glass substrate in which fine projections are formed over its entire surface by a film of low melting point-metal surface by sputtering (Kogure, T., et al., "High-Coercivity magnetic Hard Disks Using Glass Substrates," J. Appl. Phys. 67(9):4701(1990).)
This method, however, requires the texture to be formed having a height and a density greater than certain values such that the frictional force between the substrate and the magnetic head is reduced in the CSS region, where the magnetic head alternately touches and leaves the substrate. This requirement limits the degree to which the distance between the substrate and the magnetic head can be reduced.
The present invention has been made in view of the problems associated with the prior art. Accordingly, an object of the present invention is to provide a recording medium in which the contact of the substrate with the magnetic head can be prevented in the seek operation while the distance between the substrate and the magnetic head is minimized.
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The heart includes four valves that serve to direct blood flow through the two sides of the heart. On the left (systemic) side of the heart are: (1) the mitral valve, located between the left atrium and the left ventricle, and (2) the aortic valve, located between the left ventricle and the aorta. These two valves direct oxygenated blood from the lungs through the left side of the heart and into the aorta for distribution to the body. On the right (pulmonary) side of the heart are: (1) the tricuspid valve, located between the right atrium and the right ventricle, and (2) the pulmonary valve, located between the right ventricle and the pulmonary artery. These two valves direct de-oxygenated blood from the body through the right side of the heart and into the pulmonary artery for distribution to the lungs, where the blood becomes re-oxygenated in order to begin the circuit anew.
All four of these heart valves are passive structures in that they do not themselves expend any energy and do not perform any active contractile function. They consist of moveable “leaflets” that open and close in response to differential pressures on either side of the valve. Any or all of these heart valves in a particular patient may exhibit abnormal anatomy and function as a result of congenital or acquired valve disease. Congenital valve abnormalities may be well-tolerated for many years only to develop into a life-threatening problem in an elderly patient, or may be so severe that emergency surgery is required within the first few hours of life. Acquired valve disease may result from causes such as rheumatic fever, degenerative disorders of the valve tissue, bacterial or fungal infections, and trauma.
The problems that can develop with valves can generally be classified into two categories: (1) stenosis, in which a valve does not open properly, and (2) insufficiency (also called regurgitation), in which a valve does not close properly. Stenosis and insufficiency may occur concomitantly in the same valve or in different valves. Both of these abnormalities increase the workload placed on the heart. The severity of this increased stress on the heart and the patient, and the heart's ability to adapt to it, determine the treatment options that will be pursued. In some cases, medication can be sufficient to treat the patient, which is the preferred alternative; however, in many cases defective valves have to be repaired or completely replaced in order for the patient to live a normal life.
The two general categories of valves that are available for implantation into the cardiac system are mechanical valves and bioprosthetic or tissue valves. Mechanical valves have been used for many years and encompass a wide variety of designs that accommodate the blood flow requirements of the particular location where they will be implanted. Although the materials and design features of these valves are continuously being improved, they do increase the risk of clotting in the blood stream, which can lead to a heart attack or stroke. Thus, mechanical valve recipients must take anti-coagulant drugs for life to lessen the potential for blood clot formation. Further, mechanical valves can sometimes suffer from structural problems that may force the patient to have additional surgeries for further valve replacement.
Bioprosthetic valves, which are sometimes also referred to as prosthetic valves, generally include both human tissue valves and animal tissue valves. Prosthetic heart valves are described, for example, in U.S. Patent Publication No. 2004/0138742 A1 (Myers et al.), the entire contents of which are incorporated herein by reference. The designs of these bioprosthetic valves are typically relatively similar to the design of the natural valves of the patient and advantageously do not require the use of long-term anti-coagulant drugs. Human tissue valves are typically not available in large quantities since they must be removed from deceased persons who have elected organ donation; however, because large numbers of animals are routinely processed at meat processing facilities, for example, animal tissue valves are more widely available for the patients who require valve replacement. The most common types of animal tissue valves used include porcine aortic valves, and bovine and porcine pericardial valves, some of which are incorporated with some type of a stent before implantation in a patient.
To simplify surgical procedures and reduce patient trauma, there has been a recent increased interest in minimally invasive and percutaneous replacement of cardiac valves. Percutaneous replacement of a heart valve does not involve actual physical removal of the diseased or injured heart valve. Rather, the defective or injured heart valve typically remains in position while the replacement valve is inserted into a catheter and delivered percutaneously via the vascular system to the location of the failed heart valve. There, the replacement valve is either expanded by the balloon or self-expands to compress the native valve leaflets against the ventricular outflow tract, anchoring and sealing the replacement valve. In the context of percutaneous, pulmonary valve replacement, U.S. Patent Application Publication Nos. 2003/0199971 A1 (Tower, et al.) and 2003/0199963 A1 (Tower, et al.), describe a valved segment of bovine jugular vein, mounted within an expandable stent, for use as a replacement pulmonary valve. As described in the articles “Percutaneous Insertion of the Pulmonary Valve”, Bonhoeffer, et al., Journal of the American College of Cardiology 2002; 39: 1664-1669 and “Transcatheter Replacement of a Bovine Valve in Pulmonary Position”, Bonhoeffer, et al., Circulation 2000; 102: 813-816, the replacement pulmonary valve may be implanted to replace native pulmonary valves or prosthetic pulmonary valves located in valved conduits. Other implantables and implant delivery devices also are disclosed in published U.S. Patent Application Publication No. 2003/0036791 A1 (Bonhoeffer et al.) and European Patent Application No. 1 057 460-A1. In addition, percutaneous heart valves for use as a replacement pulmonary valve are described in Assignee's co-pending U.S. Patent Application Publication No. 2006/0206202 A1 (Bonhoeffer et al.). Like the valves described by Tower et al., the heart valves of this co-pending application incorporate a valved segment of bovine jugular vein, which is mounted within an expandable stent.
There is, however, a continued need to be able to be able to provide a variety of different valve assemblies to accommodate the requirements of different patients, such as by providing stented valves that can be designed and customized for each individual patient.
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Memory is one type of integrated circuitry and is used in computer systems for storing data. Memory may be fabricated in one or more arrays of individual memory cells. Memory cells may be written to, or read from, using digit lines (which may also be referred to as bitlines, data lines, or sense lines) and access lines (which may also be referred to as wordlines). The sense lines may conductively interconnect memory cells along columns of the array, and the access lines may conductively interconnect memory cells along rows of the array. Each memory cell may be uniquely addressed through the combination of a sense line and an access line.
Memory cells may be volatile, semi-volatile, or non-volatile. Non-volatile memory cells can store data for extended periods of time in the absence of power. Non-volatile memory is conventionally specified to be memory having a retention time of at least about 10 years. Volatile memory dissipates and is therefore refreshed/rewritten to maintain data storage. Volatile memory may have a retention time of milliseconds or less. Regardless, memory cells are configured to retain or store memory in at least two different selectable states. In a binary system, the states are considered as either a “0” or a “1”. In other systems, at least some individual memory cells may be configured to store more than two levels or states of information.
A field effect transistor is one type of electronic component that may be used in a memory cell. These transistors comprise a pair of conductive source/drain regions having a semiconductive channel region there-between. A conductive gate is adjacent the channel region and separated there-from by a thin gate insulator. Application of a suitable voltage to the gate allows current to flow from one of the source/drain regions to the other through the channel region. When the voltage is removed from the gate, current is largely prevented from flowing through the channel region. Field effect transistors may also include additional structure, for example a reversibly programmable charge-storage region as part of the gate construction between the gate insulator and the conductive gate.
Flash memory is one type of memory and has numerous uses in modern computers and devices. For instance, modern personal computers may have BIOS stored on a flash memory chip. As another example, it is becoming increasingly common for computers and other devices to utilize flash memory in solid state drives to replace conventional hard drives. As yet another example, flash memory is popular in wireless electronic devices because it enables manufacturers to support new communication protocols as they become standardized, and to provide the ability to remotely upgrade the devices for enhanced features.
NAND may be a basic architecture of integrated flash memory. A NAND cell unit comprises at least one selecting device coupled in series to a serial combination of memory cells (with the serial combination commonly being referred to as a NAND string). NAND architecture may be configured in a three-dimensional arrangement comprising vertically-stacked memory cells individually comprising a reversibly programmable vertical transistor. Control or other circuitry may be formed below the vertically-stacked memory cells.
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1. Field of the Invention.
The present invention relates to a washing machine and more particularly to a rotatable plastic wash basket having sufficient rigidity to prevent undue vibration and deflection.
2. Description of the Prior Art.
Rotatable wash baskets for use in automatic washers may be subject to various types of forces during basket spin and may have particular dynamic responses to forced vibrations which may occur during basket spin. The types of forces experienced by the basket typically include a centrifugal force created by an evenly distributed load of clothes, a localized imbalance force created by an unevenly distributed load of clothes and a reactive force applied at the top lip of the basket by spinning water in a balance ring. The wash basket is typically supported by a hub member which is interconnected with a drive shaft for supporting and rotating the wash basket. The localized imbalance force resulting from an unevenly distributed load of clothes creates a moment at the hub member, and if uncorrected, may create undesired vibration in the wash basket during rotation. Preferably, the reactive force resulting from the spinning water in the balance ring will create a substantially equal and opposite moment at the hub member for correction of the localized imbalance such that undesired vibration is prevented. An eccentric spin condition must exist for the balance ring to function therefore some small difference typically exists between the moment created by the reactive force at the hub member and and the moment created by the localized imbalance force at the hub member. However, due to physical size limitations in the balance ring, in the case of large localized imbalance forces large differences in moments may exist. These differences result in an overall imbalanced condition for the wash basket which subjects the rotating wash basket to forced vibrations during spin. These forced vibrations will have a frequency equal to the spin frequency (basket revolutions/sec) of the rotatable wash basket.
Typically, rotatable wash baskets for use in an automatic washer are constructed of metal. For example, U.S. Pat. No. 4,890,465 shows a metallic rotatable wash basket having a single wall basket structure including a single wall base structure. U.S. Pat. No. 2,921,460 shows a metallic rotatable wash basket having a single wall basket structure including a single wall base structure having an additional rigid metallic bottom plate attached to the base for providing base rigidity. Because of the inherent stiffness and strength of metal, rotatable wash baskets made of metal are sufficient to withstand the various forces to which a rotatable wash basket may be subjected.
It is also well known to utilize plastic rotatable wash baskets in an automatic washer. The use of a plastic material for a rotatable wash basket may offer various advantages over metal including lower cost and corrosion resistance. However, the strength of plastic is such that simple single wall wash basket construction, similar to metallic wash basket designs, may not have adequate strength and stiffness. Plastic processing limitations prevent wash basket designers from simply increasing the thickness of the plastic walls to improve wash basket strength. Therefore, to provide adequate strength and stiffness in a plastic basket, various wash basket reinforcement configurations are employed. These wash basket reinforcement configurations are typically intended to provide additional strength to the bottom or base of the wash basket. In particular, the prior art shows the use of reinforcing ribs located on the base of a plastic rotatable wash basket or the use of a rigid metallic bottom plate attached to the base of a plastic rotatable wash basket.
For example, U.S. Pat. No. 5,012,658 illustrates the use of reinforcing ribs located on the base of a rotatable plastic wash basket for providing the necessary strength and stiffness. The use of reinforcing ribs, however, may have several disadvantages. The use of external ribs on the base of a wash basket may cause the formation of an undue amount of suds between the rotatable basket and an imperforate, non-rotatable tub. This suds condition may cause the automatic washer to fail to adequately perform various functions. Furthermore, ribbed base designs may still not offer equivalent strength and stiffness as compared to metallic wash baskets having metallic base structures and rotatable plastic basket having a ribbed base may be inadequate to withstand the various forces to which a rotating wash basket is subjected.
Additionally, U.S. Pat. No. 4,483,161 and U.S. Pat. No. 4,444,027 illustrate the use of a metal reinforcing plate secured to the base of a plastic rotating wash basket for providing the required stiffness and strength. The use of a metallic reinforcing plate may also have several disadvantages. The use of a reinforcing plate requires the use of fasteners which increases the difficulty of assembly. In addition, a metallic reinforcing plate may create corrosion problems. Finally, the addition of a reinforcing plate and fasteners may increase the cost of the rotatable wash basket.
In both plastic and metallic rotatable wash baskets, the deflection and the dynamic response of the rotatable wash basket may be influenced by several factors including the overall stiffness of the wash basket. In particular, the basket should preferably be designed such that the lowest natural frequency of the wash basket structure is greater than the spin frequency of the rotatable wash basket so that undue vibration may be avoided. Given the inherent stiffness and strength of metal, undue deflection or vibration has typically not been an issue in the design of metallic baskets. Typically, the lowest natural frequency of a metallic basket is higher than the spin frequency of the basket and therefore excitation of the basket at its natural frequency is avoided. However, since plastic has less inherent strength and stiffness than metal, plastic baskets typically require reinforced structure to prevent undue deflection and vibration.
Engineering analysis performed by the inventors has shown that the base which forms the bottom wall of the basket is critical in dictating the stiffness of the entire basket. Therefore, a plastic rotatable wash basket having a base geometry which provides adequate stiffness to the entire basket may provide a basket design having its lowest natural frequency higher than the spin frequency of the basket such that undue vibrations are not experienced during basket spin. Prior art, however, appears to teach the use of relatively thick walls in the vertical cylindrical portion of the plastic wash basket for achieving stiffness and strength. This manner of providing basket stiffness for preventing undue deflection and vibration is relatively ineffective and expensive. Therefore, a basket having a base geometry which provides adequate stiffness may have a cylindrical outerwall portion of the basket having a wall thickness less than a wash basket having a base with inadequate stiffness such that a basket having an adequately stiff base may use less material than a basket having an inadequately stiff base.
There is, therefore, a need for a plastic rotatable wash basket for use in an automatic washer having a structure sufficient to withstand the forces applied to the basket, but which does not create a sudsing problem or require additional reinforcing plates. Additionally, there is a need for a plastic rotatable wash basket having a base sufficiently stiff such that the lowest natural frequency of the rotatable basket is greater than the spin frequency of the rotatable wash basket. Furthermore, there is a need for a plastic basket construction which minimizes the basket wall thickness thereby being of relatively low cost.
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In a normal human cell, about 2 meters of DNA are folded and packaged into a nucleus less than 10 microns in diameter. Much of this compaction is performed by wrapping the DNA around nucleosomes, which are complexes composed of histone proteins. Compaction and packaging into the nucleus provides a level of protection for fragile strands of DNA. However, despite the compaction of DNA into chromosomes, double-stranded breaks in DNA are common.
DNA double-stranded breaks jeopardize a chromosome's physical integrity essential for its correct segregation during mitosis and meiosis as well as its informational redundancy critical for maintaining accurate encoding of cellular components. Given that DNA double-stranded breaks have the potential to cause a great deal of damage to the cell, it is not surprising that multiple cellular mechanisms exist for dealing with this serious lesion, including non-homologous end joining, homologous recombination, and apoptosis. On the other hand, DNA double-strand cleavages are necessary in several important cellular processes, including recombination during meiosis and mitosis, V(D)J recombination during immune system development, and mating type switching in S. cerevisiae. Aside from natural processes, DNA double-stranded breaks also appear following exposure to radiation, magnetic fields, toxins, mutagenic chemicals, various medications, and the like.
While much is known about the causes and actual rejoining of DNA double-stranded breaks, much less is known about how these breaks are initially recognized. Elucidation of an organism's initial response mechanisms to double-stranded breaks would provide a means to detect DNA double-stranded breaks. Currently, DNA breaks are detected using pulsed-field electrophoresis, filter elution, sucrose gradient sedimentation, single cell gel electrophoresis or the TdT-mediated fluorescein-dUTP nick end labeling (TUNEL) assay. The former three methods are useful for only gross measurements of DNA damage in a large sample.
Single cell gel electrophoresis, also known as the comet assay, capitalizes on the movement of fragmented DNA out of a cell body into the agarose gel toward the anode during electrophoresis. The resulting shape resembles a comet, the cell body being the comet head and the fragmented DNA being the comet tail. The comet assay, frequently used in the study of apoptosis, is an improvement over the aforementioned techniques in that it allows measurement of DNA cleavage in an individual cell. However, this technique requires a great deal of time and effort to study DNA breaks in larger samples and lacks sensitivity.
The TUNEL assay employs terminal deoxynucleotidyl transferase to incorporate modified nucleotides onto free 3′-hydroxyl ends of DNA fragments. In most cases, DNA breaks are visualized by differential staining of intact and fragmented DNA. However, the TUNEL assay, as well as the comet assay, require many hundreds of DNA double-stranded breaks to yield a positive signal.
In that only a few double-stranded breaks can result in phenotypic change and 40 double-stranded breaks result in cell death, the currently available assays clearly do not have the sensitivity to be useful in all situations, particularly with non-lethal amounts of breaks. In view of the above, there exists a need for a sensitive means of determining DNA double-stranded breaks. It is an object of the present invention to provide such a means. This and other objects and advantages of the present invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.
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(i) Field of the Invention
The subject of the invention is a process for preparing a solid composite electrolyte consisting of at least one compound of the BIMEVOX family and the use of said composite for extracting oxygen from air or from a gas mixture containing oxygen.
(ii) Description of Related Art
In order to separate oxygen from air or from a gas mixture containing it, by means of a solid-electrolyte cell or membrane, whether using a purely electrochemical process generated by a current generator or using an electrochemical semipermeability process generated by the difference in oxygen partial pressure between each of the faces of the cell or membrane, the solid electrolytes used are generally stabilized zirconias, such as those described for example in United States Patent published under the number U.S. Pat. No. 4,879,016, or oxides derived from Bi.sub.4 V.sub.2 O.sub.11, such as those described in the International Patent Application published under the number WO 91/01274 and known by the generic name BIMEVOX. The latter, in which a variable fraction of the vanadium is replaced with a metal chosen especially from alkaline-earth metals, transition metals, rare earths or elements of Groups III to V of the Periodic Table of the Elements, are O.sup.2- ionic conductors and their anionic conductivity at 500.degree. C. is of the same order of magnitude as that of stabilized zirconias at 800.degree. C. The partial substitution of the constituent elements of Bi.sub.4 V.sub.2 O.sub.11 stabilizes the gamma-phase structural type and maintains, in the O.sup.2- ion lattice, a vacancy content sufficient to allow anionic conductivity. Since the oxygen atoms of the Bi.sub.2-x M.sub.y O.sub.2 layers strongly bonded to the bismuth atoms cannot move, it therefore means that the conductivity is essentially two-dimensional; the anionic conductivity of this phase is remarkable since it reaches 10.sup.-3 .OMEGA..sup.-1 cm.sup.-1 at about 200.degree. C.
These BIMEVOX compounds are used in electrochemical cells, like those described in the International Patent Applications published under numbers WO 94/06544 and WO 94/06545, and in cells operating by electrochemical semipermeability, such as those described in French Patent Application published under the number FR 2,698,016.
However, obtaining the intrinsic properties of these BIMEVOX-based electrolytes, whether mechanical or electrical properties, is conditional on proper control of the parameters for their synthesis. The term "synthesis parameters" should be understood to mean essentially the size of the initial particles and, during sintering the temperatures, rates of temperature rise and fall and the durations of any temperature hold at a given temperature. Likewise, depending on the metal chosen as the dopant and on its content, between 0% and 50%, it is necessary for the sintering conditions to be defined very precisely. These conditions have a direct influence on the particle size of the sintered material, this size itself governing the stability and the quality of the electrical and mechanical properties of the BIMEVOX compound. It has also been found that increasing the sintering temperatures by a few tens of degrees, for example 800.degree. C. instead of 750.degree. C. in the case of Bi.sub.2 Co.sub.0.1 V.sub.0.9 O.sub.3.55, called hereafter BICOVOX. 10, has the effect of modifying the electrical properties of the material and that too great a temperature in this has the effect of favoring abnormal crystalline grain growth in BIMEVOX, therefore leading to a microstructure in the inhomogeneous material in which the average grain size exceeds the critical value of 5 .mu.m. Under these conditions, on the one hand the mechanical properties degrade and the electrical resistivity increases, and on the other hand the electrical properties are no longer either stable over time or during thermal cycles.
In addition, poor adhesion of the electrode to the electrolyte in an elementary electrochemical cell of the BIMEVOX electrolyte/volume electrode type, such as the one described in the International Patent Application published under the number WO 95/32050, may be observed, and debonding phenomena have been demonstrated during operation of the cell. Thus, it has been possible to show that the adhesion of a composite electrode of the LSM-Bi.sub.2 Co.sub.0.1 V.sub.0.9 O.sub.5.35 type (30% by volume) to an electrolyte of composition Bi.sub.2 Co.sub.0.1 O.sub.5.35 after heating at 750.degree. C., which is the maximum temperature for preventing abnormal grain growth of the electrolyte, is very poor.
The Applicant has therefore sought to develop a process for preparing a solid electrolyte comprising at least one compound of the BIMEVOX family which allows grain size of the material after sintering to be controlled and which thus results in mechanical properties that are superior compared to said BIMEVOX material alone, without the electronic and ionic properties of said material thereby suffering.
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The present invention relates in general to fiber optic devices, and in particular fiber optic sensing devices.
Sensing devices are used in a wide range of technologies. Most automated mechanical and electrical apparatus include some sort of sensing capability. Particularly prevalent are sensors that can be read electronically. In many applications, such sensors provide electrical inputs used as feedback for control circuitry.
Electronic sensors are used to measure all manner of physical phenomena such as temperature, pressure, acceleration, voltage, electromagnetic fields, etc. The variety and adaptability of electronic sensors have resulted in such sensors being utilized in a wide assortment of products.
Some sensing applications pose more difficult challenges than others. For example in aeronautic and space applications, sensors are subjected to extremes of temperature, mechanical and electrical shock, electromagnetic interference, radiation, pressure, acceleration, etc. Also, the volatile fuels used in jet aircraft and rockets require that any sensors used in fuel areas must be carefully designed to prevent electrostatic discharge.
Sensors that are immune from risk of electrostatic discharge are very desirable in many fields, including aerospace and scientific fields. Although sensors for explosive or extreme environments have been developed, the design, manufacture, and testing of such sensors results in the devices being very expensive.
An apparatus and method that address the aforementioned problems, as well as other related problems, are therefore desirable.
To overcome limitations in the prior art described above, and to overcome other limitations that will become apparent upon reading and understanding the present specification, the present invention discloses a method and apparatus for passive sensing.
In accordance with one embodiment of the invention, a sensing device gathers light from one or more light sources, each light source having a unique primary wavelength. The sensor includes one or more mirrors to reflect light from the light sources. A collector mirror is arranged to reflect light from the mirrors. A light collector is arranged to gather light reflected from the collector mirror. A MEMS actuation member is coupled to the collector mirror. The MEMS actuation member is arranged to rotate the collector mirror in response to a change in a physical phenomena. Rotation of the collector mirror causes a change in the relative intensity of the primary wavelengths of the light sources at the light collector.
In another embodiment of the present invention, a sensing device arranged to gather light from a light source includes a source mirror arranged to reflect light from the light source. One or more collector mirrors are arranged to reflect light from the source mirror. One or more light collectors arc arranged to gather light reflected from the respective collector mirrors. A MEMS actuation member is coupled to the source mirror. The MEMS actuation member is arranged to move the source mirror in response to a change in a physical phenomena. Movement of the source mirror causes a change in the relative intensities of light measured at the light collectors.
The above summary of the present invention is not intended to describe each illustrated embodiment or implementation of the present invention. This is the purpose of the figures and the associated discussion which follows.
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The type of hinge presented here is one to be used for lavatory doors in airplanes; however, it is also applicable to doors for telephone booths, unit baths and many other items.
The space required by a folding door operation is generally smaller than for an ordinary door.
Usually, double actuated piano hinges are used for folding doors.
These hinges, however, do not completely block either light or odors, consequently, when they are used for doors of airplane lavatories, these shortcomings may inconvenience passengers sitting nearby. In order to avoid this problem, a rubber-coated cloth or a similar material is used to cover the hinge areas. Nevertheless, this solution has drawbacks, because black stains appear on the cover by being rubbed during operation. On the other hand, the double hinge system has drawbacks because of the excess noise and does not always operate smoothly due to unwanted vibration.
This present invention is intended to solve the above problems, by offering a higher degree of airtightness and a greater smoothness of operation.
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Audience measurement of media (e.g., content and/or advertisements) often involves collection of media identifying information and/or data (e.g., signature(s), fingerprint(s), code(s), tuned channel identification information, time of exposure information, etc.) and people data (e.g., user identifiers, demographic data associated with audience members, etc.). The media identifying information and the people data can be combined to generate, for example, media exposure data (e.g., ratings data) indicative of amount(s) and/or type(s) of people that were exposed to specific piece(s) of media distributed via one or more distribution mediums (e.g., broadcast television and/or radio, stored audio and/or video content played back from a memory such as a digital video recorder or a digital versatile disc, a webpage, audio and/or video media presented (e.g., streamed) via the Internet, a video game, targeted broadcast, satellite broadcast, cable, video on demand, etc.).
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This application is a National Stage application under 35 U.S.C. xc2xa7371 of PCT/EP98/07321 filed Nov. 10, 1998, which claims priority from EP 97.203.568.7, filed Nov. 17, 1997.
The present invention is concerned with a pharmaceutical composition suitable as a depot formulation for administration via intramuscular or subcutaneous injection, comprising:
(1) as an active ingredient a therapeutically effective amount of a 9-hydroxy-risperidone fatty acid ester or a salt, or a stereoisomer or a stereoisomeric mixture thereof in submicron form and
(2) a pharmaceutically acceptable carrier; wherein the pharmaceutically acceptable carrier is water and the active ingredient is suspended therein;
and with a process of preparing such a composition.
The invention further involves such a pharmaceutical composition for use as a medicament in the treatment of psychosis, schizophrenia, schizoaffective disorders, non-schizophrenic psychoses, behavioural disturbances associated with neurodegenerative disorders, e.g. in dementia, behavioural disturbances in mental retardation and autism, Tourette""s syndrome, bipolar mania, depression, anxiety.
Risperidone is generic to 3-[2-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1-piperidinyl]ethyl]-6,7,8,9-tetrahydro-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one. The preparation and pharmacological activity thereof are described in EP-0,196,132 (corresponding to U.S. Pat. No. 4,804,663). Various conventional pharmaceutical dosage forms, including tablets, capsules, drops, suppositories, oral solutions and injectable solutions are exemplified therein. In practice, risperidone is normally administered as the base in a tablet or in a buffered, oral or intramuscular solution. Particular solutions for oral or intramuscular administration are described in WO-96/01652.
Risperidone is a highly potent drug having a relatively narrow therapeutic index. It may produce undesirable side effects on overdosage, most notably extra pyramidal syndrome (EPS) and to a lesser extent hypotension (due to peripheral alpha-adrenergic activity). For the purpose of producing an antipsychotic effect in a patient the total daily dose of risperidone ranges from about 2 to about 8 mg; for the alleviation of behavioral disturbances associated with neurodegenerative disorders the total daily dose is usually less and typically ranges from about 0.5 to about 2 mg. Inter-individual differences and co-medication may necessitate dose titrating in patients.
It is known that risperidone is metabolized to 9-hydroxyrisperidone which has a pharmacological profile and potency comparable with that of the parent drug risperidone, but which has a longer elimination half-life. Risperidone is distributed to and eliminated from the brain tissues more rapidly than its metabolite 9-hydroxy-risperidone. 9-hydroxyrisperidone, its enantiomeric forms and the C2-20 alkanoic acid esters thereof are described in EP-0,368,388 (corresponding to U.S. Pat. Nos. 5,158,952 and 5,254,556). Said esters are considered to be potentially valuable prodrugs of the active metabolite of risperidone for use in depot formulations.
For a number of reasons, it is desirable to administer risperidone in a sustained or delayed release (depot) formulation which is effective over an extended period of time, preferably about 3 weeks or more, in particular about 1 month.
WO-94/25460 (corresponding to EP-0,697,019) relates to a first such depot formulation and concerns the risperidone pamoate salt, a poorly water-soluble salt form of risperidone, which may be suspended in a pharmaceutically acceptable carrier, such as water or an oil, and may be administered subcutaneously or intramuscularly. This salt, however, has pharmacokinetic properties which are suboptimal. The release of the active ingredient from the formulations appears to be too rapid, which results in relatively high initial plasma levels and an inadequate mean duration of action, both characteristics which should be improved upon in a truly effective depot formulation.
WO-95/13814 concerns sustained release formulations for parenteral administration wherein risperidone is microencapsulated in a biocompatible, biodegradable wall-forming material (e.g. a polymer such as dl-(polylactide-co-glycolide)). The micro-encapsulated formulations have suitable pharmacokinetic properties, but require sophisticated processes of preparation in a purpose-built plant.
PCT/EP97/02504 discloses aqueous suspensions of 9-hydroxyrisperidone fatty acid esters in water wherein the prodrug of the active ingredient is in micronized fonn. Unexpectedly, these formulations prove to be far too longlasting in humans to be therapeutically useful.
Consequently, there is still a need for an effective and readily available depot formulation of risperidone or a risperidone-like compound.
Nanoparticles are well known in the prior art, having been described, for example, in EP-A-0,499,299. These particles consist essentially of a crystalline drug substance having a surface modifier absorbed on the surface of the particles such that the effective average particle size is less than about 400 nm. It is also known that said particles are particularly useful to formulate poorly water soluble active ingredients.
The present invention results from the investigations into the development of an efficient, well-tolerated, sustained or delayed release (depot) formulation of a 9-hydroxyrisperidone alkanoic acid ester which is therapeutically effective for at least three weeks or more, in particular about 1 month. By the expression xe2x80x9ceffective for at least three weeks or morexe2x80x9d, one means that the plasma level of the active ingredient, 9-hydroxyrisperidone (free alcohol liberated by hydrolysis from the alkanoic acid ester), should be above approximately 10 ng/ml. On the other hand, said plasma level should remain at all times below a threshold value of approximately 100 ng/ml in order for one to call the formulation xe2x80x9cefficientxe2x80x9d. The threshold value is the mean plasma level during a considerable period of time, e.g. for more than 15 minutes, above which patients may experience undesirable side effects, or conversely, the value of the plasma level under which the systemic tolerance of the formulation in question is still acceptable. The threshold value does not hold for transient, high plasm levels during a short period of time, e.g. for less than 15 minutes, which are due, for example to unexpected burst-release of the active ingredient.
Both of the foregoing featuresxe2x80x94plasma levels above a minimal therapeutical concentration but below a side-effect producing threshold valuexe2x80x94are considered to be basic requirements that a contemporary depot formulation should fulfil in order to be acceptable for the intended patients. Limiting the number of drug administrations and the occurrence of undesirable side effects after each administration will undoubtedly improve the patients"" compliance with the therapy. However, beyond these basic requirements, a number of further desiderata can be identified which would further improve patients"" compliance; the two most notable being good local tolerance and ease of administration.
Good local tolerance means minimal irritation and inflammation at the site of injection; ease of administration refers to the size of needle and length of time required to administer a dose of a particular drug formulation. In addition, depot formulations should be stable and have a shelf-life of at least two years under normal conditions.
The investigations into the development of an efficient, well-tolerated, sustained or delayed release (depot) formulation of a 9-hydroxyrisperidone alkanoic acid ester which fulfils the above mentioned requirements, led to the finding that a pharmaceutical composition suitable as a depot formulation for administration by intramuscular or subcutaneous injection should comprise:
a dispersion of particles consisting essentially of a therapeutically effective amount of a crystalline 9-hydroxyrisperidone fatty acid ester having the formula
xe2x80x83or a salt, or a stereoisomer or a stereoisomeric mixture thereof, wherein R represents a straight C9-19alkyl radical; having a surfactant absorbed to the surface thereof in an amount effective in maintaining a specific surface area greater than 4 m2/g (corresponding to an effective average particle size of less than 2,000 nm), in a pharmaceutically acceptable carrier comprising water.
Surprisingly, it appears that aqueous suspensions of micronized 9-hydroxyrisperidone C10-20 alkanoic acid esters (wherein R represents a straight C9-19 alkyl radical) have an exceptionally longlasting effect in humans, but not in test animals, in particular dogs. This is quite unexpected since the pharmacokinetics of drugs in humans and in dogs are often comparable. The pharmacokinetic properties in humans of the aqueous suspensions of 9-hydroxyrisperidone alkanoic acid esters depend on the particle size to a much larger extent than previously held possible.
C10-20alkanoic acids are selected from the group consisting of decanoic (capric), undecanoic, dodecanoic (lauric), tridecanoic, tetradecanoic (myristic), pentadecanoic, hexadecanoic (palmitic), heptadecanoic, octadecanoic (stearic), nonadecanoic and eicosanoic acid. The ester having a C15 (pentadecyl) chain and the active ingredient corresponding thereto being the 9-hydroxyrisperidone palmitate ester was found to be the superior ester from a pharmacokinetic, as well as from a tolerance point of view.
The nanoparticles of the present invention have a surfactant or surface modifier adsorbed on the surface thereof in an amount sufficient to maintain a specific surface area greater than 4 m2/g (i.e. corresponding to an average particle size of less than 2,000 nm), preferably the specific surface area greater than 6 m2/g, and in particular is in the range from 10 to 16 m2/g. Useful surface modifiers are believed to include those which physically adhere to the surface of the active agent but do not chemically bond thereto.
Suitable surface modifiers can preferably be selected from known organic and inorganic pharmaceutical excipients. Such excipients include various polymers, low molecular weight oligomers, natural products and surfactants. Preferred surface modifiers include nonionic and anionic surfactants. Representative examples of excipients include gelatin, casein, lecithin (phosphatides), gum acacia, cholesterol, tragacanth, stearic acid, benzalkonium chloride, calcium stearate, glyceryl monostearate, cetostearyl alcohol, cetomacrogol emulsifying wax, sorbitan esters, polyoxyethylene allcyl ethers, e.g., macrogol ethers such as cetomacrogol 1000, polyoxyethylene castor oil derivatives, polyoxyethylene sorbitan fatty acid esters, e.g., the commercially available Tweens(trademark), polyethylene glycols, polyoxyethylene stearates, colloidal silicon dioxide, phosphates, sodium dodecylsulfate, carboxymethylcellulose calcium, carboxymethylcellulose sodium, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose phthalate, noncrystalline cellulose, magnesium aluminate silicate, triethanolamine, polyvinyl alcohol (PVA), poloxamers, tyloxapol and polyvinylpyrrolidone (PVP). Most of these excipients are described in detail in the Handbook of Pharmaceutical Excipients, published jointly by the American Pharmaceutical Association and The Pharmaceutical Society of Great Britain, the Pharmaceutical Press, 1986. The surface modifiers are commercially available and/or can be prepared by techniques known in the art. Two or more surface modifiers can be used in combination.
Particularly preferred surface modifiers include polyvinylpyrrolidone; tyloxapol; poloxamers, such as Pluronic(trademark) F68, F108 and F127 which are block copolymers of ethylene oxide and propylene oxide available from BASF; poloxamines, such as Tetronic(trademark) 908 (T908) which is a tetrafunctional block copolymer derived from sequential addition of ethylene oxide and propylene oxide to ethylenediamine available from BASF; dextran; lecithin; Aerosol OT(trademark) (AOT) which is a dioctyl ester of sodium sulfosuccinic acid available from Cytec Industries; Duponol(trademark) P which is a sodium lauryl sulfate available from DuPont; Triton(trademark) X-200 which is an alkyl aryl polyether sulfonate available from Rohm and Haas; Tweens(trademark) 20, 40, 60 and 80 which are polyoxyethylene sorbitan fatty acid esters available from ICI Speciality Chemicals; Span(trademark) 20, 40, 60 and 80 which are sorbitan esters of fatty acids; Arlacel(trademark) 20, 40, 60 and 80 which are sorbitan esters of fatty acids available from Hercules, Inc.; Carbowax(trademark) 3550 and 934 which are polyethylene glycols available from Union Carbide; Crodesta(trademark) F110 which is a mixture of sucrose stearate and sucrose distearate available from Croda Inc.; Crodesta(trademark) SL-40 which is available from Croda, Inc.; hexyldecyl trimethyl ammonium chloride (CTAC); bovine serum albumin and SA90HCO which is C18H17CH2(CON(CH3)CH2(CHOH)4CH2OH)2. The surface modifiers which have been found to be particularly useful include tyloxapol and a poloxamer, preferably, Pluronic(trademark) F108 and Pluronic(trademark) F68.
Pluronic(trademark) F108 corresponds to poloxamer 338 and is the polyoxyethylene, polyoxypropylene block copolymer that conforms generally to the formula HO[CH2CH2O]x[CH(CH3)CH2O]y[CH2CH2O]zH in which the average values of x, y and z are respectively 128, 54 and 128. Other commercial names of poloxamer 338 are Hodag Nonionic(trademark) 1108-F available from Hodag, and Synperonic(trademark) PE/F108 available from ICI Americas.
The optimal relative amount of the antipsychotic agent and the surface modifier depends on various parameters. The optimal amount of the surface modifier can depend, for example, upon the particular antipsychotic agent and surface modifier selected, the critical micelle concentration of the surface modifier if it forms micelles, the surface area of the antipsychotic agent, etc. The specific surface modifier preferably is present in an amount of 0.1 to 1 mg per square meter surface area of the antipsychotic agent. In case 9-hydroxyrisperidone palmitate is used as antipsychotic agent and Pluronic(trademark) F108 as a surface modifier, a relative amount (w/w) of both ingredients of approximately 6:1 is preferred.
As used herein, an effective average particle size of less than 2,000 nm means that at least 90% of the particles have a diameter of less than 2,000 nm when measured by art-known conventional techniques, such as sedimentation field flow fractionation, photon correlation spectroscopy or disk centrifugation. With reference to the effective average particle size, it is preferred that at least 95% and, more preferably, at least 99% of the particles have a particle size of less than the effective average particle size, e.g. 2,000 nm. Most preferably, essentially all of the particles have a size of less than 2,000 nm.
The particles of this invention can be prepared by a method comprising the steps of dispersing an antipsychotic agent in a liquid dispersion medium and applying mechanical means in the presence of grinding media to reduce the particle size of the antipsychotic agent to an effective average particle size of less than 2,000 nm. The particles can be reduced in size in the presence of a surface modifier. Alternatively, the particles can be contacted with a surface modifier after attrition.
A general procedure for preparing the particles of this invention includes
(a) obtaining an antipsychotic agent in micronized form;
(b) adding the micronized antipsychotic agent to a liquid medium to form a premix; and
(c) subjecting the premix to mechanical means in the presence of a grinding medium to reduce the effective average particle size.
The selected antipsychotic agent in micronized form is obtained commercially or prepared using techniques known in the art. It is preferred that the particle size of the micronized antipsychotic agent be less than about 100 xcexcm as determined by sieve analysis. If the particle size of the micronized antipsychotic agent is greater than about 100 xcexcm, then it is preferred that the particles of the antipsychotic agent be reduced in size to less than 100 xcexcm.
The micronized antipsychotic agent can then be added to a liquid medium in which it is essentially insoluble to form a premix. The concentration of the antipsychotic agent in the liquid medium (weight by weight percentage) can vary widely and depends on the selected antipsychotic agent, the selected surface modifer and other factors. Suitable concentrations of antipsychotic agent in compositions vary between 0.1 to 60%, preferably is from 0.5 to 30%, and more preferably, is approximately 7% (w/v).
A more preferred procedure involves the addition of a surface modifier to the premix prior to its subjection to mechanical means to reduce the effective average particle size. The concentration of the surface modifier (weight by weight percentage) can vary from 0.1% to 90%, preferably from 0.5% to 80%, and more preferably is approximately 7% (w/v).
The premix can be used directly by subjecting it to mechanical means to reduce the effective average particle size in the dispersion to less than 2,000 nm. It is preferred that the premix be used directly when a ball mill is used for attrition. Alternatively, the antipsychotic agent and, optionally, the surface modifier, can be dispersed in the liquid medium using suitable agitation such as, for example, a roller mill or a Cowles type mixer, until a homogeneous dispersion is achieved.
The mechanical means applied to reduce the effective average particle size of the antipsychotic conveniently can take the form of a dispersion mill. Suitable dispersion mills include a ball mill, an attritor mill, a vibratory mill, a planetary mill, media millsxe2x80x94such as a sand mill and a bead mill. A media mill is preferred due to the relatively shorter milling time required to provide the desired reduction in particle size. For media milling, the apparant viscosity of the premix preferably is anywhere between 0.1 and 1 Paxc2x7s. For ball milling, the apparant viscosity of the premix preferably is anywhere etween 1 and 100 mPaxc2x7s.
The grinding media for the particle size reduction step can be selected from rigid media preferably spherical or particulate in form having an average size less than 3 mm and, more preferably, less than 1 mm. Such media desirably can provide the particles of the invention with shorter processing times and impart less wear to the milling equipment. The selection of the material for the grinding media is believed not to be critical. However, 95% ZrO stabilized with magnesia, zirconium silicate, and glass grinding media provide particles having levels of contamination which are believed to be acceptable for the preparation of pharmaceutical compositions. Further, other media, such as polymeric beads, stainless steel, titania, alumina and 95% ZrO stabilized with yttrium, are useful. Preferred grinding media have a density greater than 2.5 g/cm3 and include 95% ZrO stabilized with magnesia and polymeric beads.
The attrition time can vary widely and depends primarily upon the particular mechanical means and processing conditions selected. For rolling mills, processing times of up to two days or longer may be required.
The particles must be reduced in size at a temperature which does not significantly degrade the antipsychotic agent. Processing temperatures of less than 30 to 40xc2x0 C. are ordinarily preferred. If desired, the processing equipment may be cooled with conventional cooling equipment. The method is conveniently carried out under conditions of ambient temperature and at processing pressures which are safe and effective for the milling process.
The surface modifier, if it was not present in the premix, must be added to the dispersion after attrition in an amount as described for the premix above. Thereafter, the dispersion can be mixed by, for example, shaking vigorously. Optionally, the dispersion can be subjected to a sonication step using, for example, a ultrasonic power supply.
Aqueous compositions according to the present invention conveniently further comprise a suspending agent and a buffer, and optionally one or more of a preservative and an isotonizing agent. Particular ingredients may function as two or more of these agents simultaneously, e.g. behave like a preservative and a buffer, or behave like a buffer and an isotonizing agent.
Suitable suspending agents for use in the aqueous suspensions according to the present invention are cellulose derivatives, e.g. methyl cellulose, sodium carboxymethyl cellulose and hydroxypropyl methyl cellulose, polyvinylpyrrolidone, alginates, chitosan, dextrans, gelatin, polyethylene glycols, polyoxyethylene- and polyoxy-propylene ethers. Preferably sodium carboxymethyl cellulose is used in a concentration of 0.5 to 2%, most preferably 1% (w/v). Suitable wetting agents for use in the aqueous suspensions according to the present invention are polyoxyethylene derivatives of sorbitan esters, e.g. polysorbate 20 and polysorbate 80, lecithin, polyoxyethylene- and polyoxypropylene ethers, sodium deoxycholate. Preferably polysorbate 20 is used in a concentration of 0.5 to 3%, more preferably 0.5 to 2%, most preferably 1.1% (w/v).
Suitable buffering agents are salt of weak acids and should be used in amount sufficient to render the dispersion neutral to very slightly basic (up to pH 8.5), preferably in the pH range of 7 to 7.5. Particularly preferred is the use of a mixture of disodium hydrogen phosphate (anhydrous) (typically about 0.9% (w/v)) and sodium dihydrogen phosphate monohydrate (typically about 0.6% (w/v)). This buffer also renders the dispersion isotonic and, in addition, less prone to flocculation of the ester suspended therein.
Preservatives are antimicrobials and anti-oxidants which can be selected from the group consisting of benzoic acid, benzyl alcohol, butylated hydroxyanisole, butylated hydroxytoluene, chlorbutol, a gallate, a hydroxybenzoate, EDTA, phenol, chlorocresol, metacresol, benzethonium chloride, myristyl-xcex3-piccolinium chloride, phenylmercuric acetate and thimerosal. In particular, it is benzyl alcohol which can be used in a concentration up to 2% (w/v), preferably up to 1.5% (w/v).
Isotonizing agents are, for example, sodium chloride, dextrose, mannitol, sorbitol, lactose, sodium sulfate. The suspensions conveniently comprise from 0 to 10% (w/v) isotonizing agent. Mannitol may be used in a concentration from 0 to 7% More preferably, however, from about 1 to about 3% (w/v), especially from about 1.5 to about 2% (w/v) of one or more electrolytes are used to render the suspension isotonic, apparently because ions help to prevent flocculation of the suspended ester. In particular electrolytes of the buffer serve as isotonizing agent.
A particularly desirable feature for an injectable depot formulation relates to the ease with which it can be administered. In particular such an injection should be feasible using a needle as fine as possible in a span of time which is as short as possible. This can be accomplished with the aqueous suspensions of the present invention by keeping the viscosity below about 75 mPaxc2x7s, preferably below 60 mPaxc2x7s. Aqueous suspensions of such viscosity or lower can both easily be taken up in a syringe (e.g. from a vial), and injected through a fine needle (e.g a 21 G 1xc2xd, 22 G 2 or 22 G 1xc2xc needle).
Ideally, aqueous suspensions according to the present invention will comprise as much prodrug as can be tolerated so as to keep the injected volume to a minimum, and as little of the other ingredients as possible. In particular, such a composition will comprise by weight based on the total volume of the composition:
(a) from 3 to 20% (w/v) of the prodrug;
(b) from 0.5 to 2% (w/v) of a wetting agent;
(c) one or more buffering agents sufficient to render the composition neutral to very slightly basic (pH 8.5);
(d) from 0.5 to 2% (w/v) of a suspending agent;
(e) up to 2% (w/v) preservatives; and
(f) water q.s. ad 100%.
In view of the usefulness of 9-hydroxyrisperidone in the treatment of a number of disorders, the present invention also concerns a pharmaceutical composition as described hereinbefore for use as a medicament in the treatment of psychosis, schizophrenia, schizoaffective disorders, non-schizophrenic psychoses, behavioural disturbances associated with neurodegenerative disorders, e.g. in dementia, behavioural disturbances in mental retardation and autism, Tourette""s syndrome, bipolar mania, depression, anxiety.
In addition, the present invention concerns the use of a composition as described hereinbefore for the preparation of a medicament for treating psychosis, schizophrenia, schizoaffective disorders, non-schizophrenic psychoses, behavioural disturbances associated with neurodegenerative disorders, e.g. in dementia, behavioural disturbances in mental retardation and autism, Tourette""s syndrome, bipolar mania, depression, anxiety.
The present invention further concerns a method of treating warm-blooded animals, in particular humans suffering from psychosis, schizophrenia, schizoaffective disorders, non-schizophrenic psychoses, behavioural disturbances associated with neurodegenerative disorders, e.g. in dementia, behavioural disturbances in mental retardation and autism, Tourette""s syndrome, bipolar mania, depression, anxiety, said method comprising the administration of a therapeutically effective amount of an, aqueous suspension as described hereinbefore. Typically, said formulation will be administered approximately every three weeks or even at longer intervals where possible. The dosage should range from about 2 to 4 mg/kg body weight.
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The present invention relates to a lifting system for lifting interchangeable truck bodies or freight containers adapted to be hauled by automotive trucks.
Such truck bodies or containers are known which are provided at their four corners with hydraulic cylinders having vertical axes. These cylinders serve to make the body or container interchangeable, permitting its removal from a hauling vehicle during loading and unloading operations, and its subsequent mounting on the same or on another vehicle for transport purposes. Furthermore, during the loading and unloading operations, these cylinders enable the height of the bottom of the body or container to be continuously varied, thereby facilitating the operations.
Known lifting devices have a shortcoming concerned with the synchronization of the lift cylinders, that is to say, the operation of the four cylinders at the same moment, even with a load badly centered in the body or freight container. If in fact the four cylinders are operated by a single pump and if a badly centered load is placed in the body, it may happen that the pump fluid will pass more easily into the less loaded cylinders, thereby unequalizing the system and possibly overturning the body or container.
In order to overcome this fault, it has been proposed in the art to feed the four cylinders by means of flow dividers, which are able to supply the same amounts of fluid to the four cylinders independently of the inlet pressures of the latter.
Nevertheless, this solution has various shortcomings. Firstly, the same extension of the four cylinders insures that the body or container will rest on the ground only if the latter is entirely flat. Secondly, the limited precision of the flow dividers, due to the length of the cylinders, may give rise to an unacceptable difference in the extension of the cylinder, since the points of support on the ground may not be coplanar. Finally, the hydraulic circuit is fairly complex, delicate, and expensive.
Therefore, according to the present invention, the shortcomings of the known prior art are completely corrected by a novel fluid circuit arrangement in which the four lift cylinders are incorporated. In a preferred embodiment of the invention, the truck body or container lifting system comprises four doubleacting cylinders which are respectively disposed at the four corners of a rectangular array, the cylinders comprising two pairs of cylinders, each pair of which includes one cylinder which is connected in series to the cylinder at the diagonally opposite corner of the rectangular array.
Each cylinder of the system is preferably vertically disposed and contains a piston which divides the cylinder into an upper and a lower chamber, each pair of cylinders comprising a cylinder whose lower chamber is connected to the upper chamber of the other cylinder of the pair. Preferably, the effective cross sectional areas of the interconnected upper and lower chambers are equal to each other.
Means may be provided for insuring that the fluid pressures prevailing in the two said pairs are substantially equal. Thus, the means may comprise maximum pressure relief valves which are connected between an inlet and an outlet of one of the two cylinders of each pair.
Preferably, the upper chamber of one cylinder of each said pair is connected to a common first pipe for the supply of pressure fluid thereto, the lower chamber of one cylinder of each pair being connected to a common second pipe for the supply of pressure fluid thereto.
The upper ends of the cylinders may engage a common load.
Other features and advantages of the invention will become apparent during the course of the following description.
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1. Field of the Invention
The present invention is related to a system to treat diseases by substituting native biological regulatory function. More particularly, the present invention provides a system to treat diseases by substituting native biological regulatory function that is capable of regulating organs as if their central controllers were normally functioning even if the central controllers themselves become abnormal due to various causes. The invention includes a cardiac pacing system, a blood pressure regulating system, and a cardiac disease treatment system, all of which are particular embodiments of the medical treatment system.
2. Description of the Related Art
Heart transplantation from brain dead subjects became legal in Japan to treat patients with severe heart failure. However, the number of heart donors is definitely small, and the shortage of hearts for transplantation has been seriously discussed worldwide.
An alternative treatment for patients with severe heart failure is artificial heart implantation. However, even the most recent artificial hearts are not regulated by native biological regulation, thereby they do not always operate in concert with native organs.
Pacemakers have been used for the treatment of patients with bradycardia. Pacemakers enable necessary rhythmic myocardial contraction by electrically stimulating the myocardium artificially.
Recently rate-responsive pacemakers have been developed, in which stimulation rate changes according to the estimated native heart rate from e.g., electrocardiographic QT time, body temperature, or body acceleration. However, specificity, sensitivity and transient response of heart rate regulation compared to native heart rate regulation by such pacemakers have not always been satisfactory.
In some other diseases, it is well known that abnormal native regulatory function promotes disease processes. For example, it is known that abnormal native regulatory mechanisms participate in the progression of heart disease, and it is well known that sympathetic nerve overactivation and abnormal vagal nerve withdrawal occur after the onset of acute myocardial infarction, and worsens the outcome.
Such abnormal native regulatory function can also be observed in circulatory diseases other than heart diseases.
Even in normal subjects, 300 to 800 mL of blood shifts to the lower extremities and internal organs below the heart level during standing, causing decreased venous return to the heart and hypotension. Normal subjects usually have a blood pressure regulating mechanism to counteract this and to maintain a constant blood pressure, thereby preventing orthostatic hypotension. Subjects with various disorders and a damaged blood pressure regulating system, however, suffer from orthostatic hypotension. For example, in patients with Shy-Drager syndrome, a part of the nervous system involved in blood pressure regulation becomes abnormal, and quality of life is seriously impaired due to large fluctuations in blood pressure with their body position change.
Artificial organs and artificial devices, such as conventional artificial hearts and cardiac pacemakers, do not always operate in concert with native organs, as described above, because they are not intended to be controlled by the native regulatory system. Therefore their performance, in terms of sensitivity to changes in the native organs, is not satisfactory.
Pharmacological treatment with drugs such as coronary vasodilators, β-adrenergic blockers and anti-platelet agents, catheter-based interventional treatment, and coronary artery bypass surgery have been developed as treatments for myocardial infarction.
However, even when taking full advantage of all of the pharmacological, interventional and surgical treatments available, progression of pathology even to death is often inevitable.
Adrenergic agonists, such as epinephrine, levodopa and amphetamine, are used for pharmacological treatment of Shy-Drager syndrome with severe orthostatic hypertension, and excessive salt is administered for symptomatic relief. Although symptoms can be alleviated to some extent, it is impossible to treat Shy-Drager syndrome and restore full function.
The present invention provides a system to treat diseases that is capable of regulating organs as if their central controllers were normally functioning even if the central controllers themselves become abnormal by various causes. The present invention includes embodiments directed to a cardiac pacing system, a blood pressure regulating system, and a cardiac disease treatment system, all of which are based on the above medical treatment system.
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The present invention relates to an air-fuel ratio control system for an internal combustion engine having an emission control system with a three-way catalytic converter for controlling air-fuel ratio correcting means in accordance with conditions of engine operation by detecting cooling water temperature and load on the engine.
Conventionally, this type of air-fuel ratio control system achieves a feedback control by detecting the air-fuel ratio from oxygen concentration in exhaust gases by an O.sub.2 sensor. The detected air-fuel ratio is determined by a comparison circuit as to whether it is lean or rich comparing with the stoichiometric air-fuel ratio to produce an output signal. The output signal is sent to an electro-magnetic valve through a driver to actuate the valve for supplying a certain amount of air to a carburetor, and controlling the air-fuel ratio of the air-fuel mixture to the stoichiometric air-fuel ratio. The air-fuel ratio control system of such construction functions in good condition when the engine operates at a proper engine temperature. However, under cold engine operating condition, it is difficult to control the air-fuel ratio in accordance with the engine operation. Therefore, in an engine having an automatic choke device, the air-fuel ratio control system is so arranged that the system is rendered inoperative in the cold engine, while the air-fuel ratio of the mixture is controlled by the operation of the automatic choke device. However, the automatic choke device tends to open the choke valve before a proper time or to open it wider than a degree proper to the warming-up of the engine. Due to such difficulties, in the conventional air-fuel ratio control systems, the air-fuel ratio is always controlled to the stoichiometric air-fuel ratio even when the engine is in cold operating condition. Therefore, although during the cold engine operating condition at a constant speed with a light load, it produces an output torque sufficient to give a steady driveability, during half-open throttle or wide-open throttle operation, stumble operation of the engine occurs so that the output of the engine decreases.
This is because, despite the condition that the engine requires a rich air-fuel ratio during cold engine, mixture of air-fuel ratio leaner than that of the engine requirement is supplied to the engine by the air-fuel ratio control system, and further the air-fuel ratio is shifted to lean side when the automatic choke valve is forced opn by the drag of the air which is sucked in during acceleration.
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1. Field of the Invention
This invention relates generally to wireless communication carriers. More particularly, it relates to location and presence-based services for the wireless industry.
2. Background of Related Art
The term “presence” in the wireless world typically relates to a network answer to the simple question “Are you available?”. For instance, if a subscriber's wireless device is turned off, they would not be available. However, if a subscriber's wireless device is turned on, and in communication with a carrier, the carrier would most likely be able to indicate to a relevant request that the subscriber is available and thus “present”. The functions and use of presence information is well known in the art.
Location information regarding subscribers is increasingly becoming available in a wireless network. This is particularly true in systems that comply with E-9-1-1 requirements. Location information relates to absolute coordinates of a wireless device.
Both Location and Presence services are message intensive on telecom networks. Message reduction in general is desirable, both to allow increased capacity in a wireless network, as well as to improve reliability of the system by reducing the number of messages.
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1. Field of the Invention
The present invention relates to data analysis, and in particular relates to a video recommendation system and method for recommending video segments by analyzing object features in videos.
2. Description of the Related Art
There are many video recommendation systems on the market, which are available on websites such as: Youtube, and Dailymotion, etc. However, the videos are evaluated by using the feedback of users, and thus the video recommendation systems may merely perform statistics and prediction for videos within a large range, and so the contents in the videos cannot be further analyzed. That is, when a user is viewing a video, the conventional video recommendation system cannot analyze the feelings of the user for different circumstances or scenes in the video, and thus the video segments related to the favorite scenes of the user cannot be recommended to users.
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The digital home is now becoming more complex with the myriad of new and emerging digital devices intended to address many user and consumer needs such as communication, entertainment, privacy and security, etc. However, given the complexity of the emerging digital home and digital environments generally, users who are technologically challenged may find it a daunting and intimidating task to manage their home networks and interconnected digital devices. Moreover, new paradigms are emerging oriented to delivering media content to and the consuming of media content at the home. Many of these paradigms rely on communication of application specific data to and/or from the Internet, as opposed to conventional telephone or broadcast video type applications. The protection of received Internet-sourced media content in addition to user-generated media content is additionally an important aspect that may be inadequately addressed by the technologically challenged user. Furthermore, with respect to Internet based data, most of the content delivery solutions are provided to the digital home networks through availability of the “two-foot” interface (i.e. the PC). It is relatively cumbersome to bring this content to the “ten-foot” interface (e.g. the television).
Thus, a need exists for a technique or devices to simplify the overall management of services and applications available to the digital home or even the small enterprise. Such a technique or devices would reduce the complexity of the maintenance, upgrading, and operation of even the more basic needs addressed by emerging digital endpoint devices and networks. Approaches that suggest greater functionality in home-based appliances fail to reduce or address the complexity of managing and provisioning those appliances. For example, while the home gateway server appliance described in U.S. Pat. No. 6,930,598 enables networked electronic devices to communicate with each other without the direct interaction with external networks, and provides a mechanism whereby a member of the household may be informed of certain network related events without having to use their home computer or other client devices, it does not provide a convenient or simplified way of managing the services and applications executed by, or associated with, that device. Thus, an unmet need exists for a device associated with a user premises that has robust functionality but does not require sophisticated or inordinate attention from the user to manage, provision and utilize them.
In practice, a customer typically subscribes to basic transport services from a network “Service Provider” (e.g. ISP-Internet Service provider, cable provider, fixed wireless providers, ILEC-Incumbent Local Exchange Carrier, or CLEC-Competitive Local Exchange Carrier). For example, a customer may have broadband Internet access, via cable modem, digital subscriber line service or the like. Digital video service may be provided separately. The network service provider manages these basic services, at the logical network layer, typically at layers 1, 2 or 3 of the OSI model. While network services and associated devices may operate minimally at those levels, they operate at those levels only to support operations at OSI layers 1, 2 or 3. Many applications, however, involve higher level service logic for applications that view the network transport as a transparent pipe. The current internet applications delivery and management architecture, and many devices or management systems based on it, require a server with robust processing and storage capability to be located at the network operations center, not in the home. For voice over internet protocol (VoIP) type telephone service, for example, the VoIP service provider operates a session initiation protocol (SIP) server or the like, and each user has only client functionality. The network transport layers are transparent to the IP packets containing the voice and related signaling. The SIP server, however, controls the call set-up, tear-down, billing and the like for the voice call services. With such an architecture, the major capabilities and functionalities connected with providing application services from the server throughout the network reside on the server and supporting elements, all of which are located in the network operations center.
It might be helpful to walk through examples of the configuration for application services delivery to a client of an application within a user premises under the typical, current network configuration. FIG. 10 depicts one possible configuration for a client application to access a particular service that is being hosted of served outside of the user premises based on the typical, and currently employed, network application service configuration. We identify two regimes in the overall architecture, the Service Provider Network regime (WAN side), and the User Premises Network regime (LAN side). The association between the Service Provider Network and the User Premises Network is broken down into three layers; Network Interconnect Layer (NI), Network Function Layer (NF), and the Application Services Layer (AS). These layers do not represent physical communication pathways, but are a logical representation of pathways and elements employed in a network-based communication.
The separation between the managed Service Provider Network (WAN side) and the User Premises Network (LAN side) is depicted as the Network Service provider Demarcation. The Network Service Provider Demarcation at the Network Interconnect Layer represents the logical and physical separation between the user premises and the broad-band network. In the present representation of the three functional layers, the Network Service Provider Demarcation is extended into the Services and Application Layer to emphasize the functional barrier at that layer between the Service Provider Network and the User Premises Network, in currently configured networks.
The NI Layer depicts how the connectivity between a User Premises Network and the Public/Service Provider Network is established. On the Service Provider Network side, the Wide Area Network services are terminated onto a WAN termination device with the appropriate interface (e.g. a Broadband internet service such as ADSL would terminate on to a managed ADSL Terminal Adapter). The WAN termination layer adapts the WAN interface into a compatible LAN interface (e.g. Ethernet or WiFi). On the User Premises Network side the LAN Termination interfaces are used to connect to the Local Area Network via a variety of interfaces, such as Ethernet, WiFi, MOCA, etc.
The LAN Termination interfaces and the WAN Termination interface could reside on two separate physical devices or they could reside on one physical device. In either case, on the User Premises Network side, packets or data must flow through the NF Layer between the WAN Termination Interface and the LAN Termination Interface. One or both of these interfaces may reside on a “gateway” device. Gateway and like router devices are currently available for various premises that allow several computers to communicate with one another and to share a broadband Internet connection. These devices function as routers by matching local network addresses and the hostnames of the local computers with the actual networking hardware detected. As gateways, these devices translate local network addresses to those used by the Internet for outgoing communications, and do the opposite translation for incoming packets.
The User Premises NF Layer allows for switching of packets between LAN devices and routing or bridging of packets between the LAN and WAN interfaces. It could physically reside on the same device(s) with the LAN Termination or it could exist at an independent device that could interconnect to the LAN Termination interface via a variety of physical interfaces (e.g. Ethernet, MOCA, etc.). The Service Provider NF Layer provides the Wide Area Network access between the WAN Termination device and the AS Layer where all the applications servers are being hosted. The Internet could be used for this connectivity as could a private packet/cell network (e.g. Cellular packet network, or a private ATM or packet backbone).
The AS Layer represents the functional layer that provides access to applications services by application clients. On the User Premises side, the AS Layer provides a Firewall to protect the application client from application level attacks from the open Internet. On the Service Provider side, the AS Layer encompasses application services such as Parental Control, Backup, and Call Processing. These application services exist on a managed Application Service Delivery Platform (ASD) on a secure network server that can be hosted at a facility that has private and or public data connection paths. The ASD may include three functional modules, namely the Application Service Enforcement (ASE) module, the Application Service Logic (ASL) module, and the Application Service Management (ASM) module.
The ASE module is responsible for enforcing the relevant Application Client privileges to the application services. It gets the policies and permissions of each application client from the ASM module (such as provisioning data and subscription data) and enforces those policies against the requested actions by the client application.
The ASL module executes the application services that the Application Clients request. Such services could be Call Processing, Parental Control, Peered Networking, Backup, etc. The ASL module must interact with the ASM module for monitoring purposes and status information such as Call Data Recording and Billing. It must also interact with the ASE module to provide access to the client applications that have passed the policy enforcement procedures.
The ASM module, as described above, provides the necessary data to the ASE and ASL modules for them to carry out their respective functions. It also oversees the overall integration and communication among all the modules and the services that are managed by the ASM. The ASM also manages the overall security and integrity of the ASD.
All ASD modules are in constant communication with each other, preferably through secure connections. The inter-module communication may be managed by the ASM, or may be independent of a central management function. Note that the ASE, ASL and ASM modules are only examples of functions that may be logically bundled; other bundles, and other means of bundling these functions, are possible.
FIG. 11 depicts a logical flow of how a specific Application Client residing at a user premises could interact with an Application Service that is being managed in the typical network configuration. Traditionally, as depicted in this example, an Application Client (e.g. Telephony) that needs to connect to an Application Service (e.g. call processing) must first connect to the Local Area Network termination interface (1). Depending on the specific deployment, a switching function, routing function or bridging function is used to establish the connection path between the application client (2) and the Firewall service (3). The Firewall Service works in conjunction with the router function (4) to permit access to the Wide Area Network interface (5) and maintain a level of security to the Application Client. The firewall service in this example is not aware of either the type of application client or the specific application service that is being targeted. There is no feedback mechanism between the Application Service Delivery Platform and the Firewall function. Once connectivity to the WAN termination interface is established, routing mechanisms are used to establish a connection through the Service Provider Network. Function Layer (6) to the Application Service Layer (7). At the Application Service Layer, the client application goes through application validation procedures and privilege and permission checks by the ASE prior to allowing the application client to connect to the desired application service.
In the logical hierarchy, such as shown in FIGS. 10 and 11, a home gateway device may implement the NI layer functions and the user premises side NF layer functions. The firewall functionality may reside in the gateway or in one or more other elements on the premises network. For example, many PCs internally implement firewalls, e.g. in close association with the client programming of the endpoint device. As can be seen by the illustrations in FIG. 11, however, even with a home gateway deployment for a premises network, the application services functionality still requires the support and service logic to reside on a server in the network. That is, for service provisioning, service management and upgrades, remote diagnostics, for a digital endpoint device such as a PC or SIP phone, the home premises still must rely on the application service logic executed by the service providers in their server networks, typically according to proprietary platforms. Moreover, many other core services, e.g. file storage, media content access and delivery, are offloaded to other 3rd-party service providers that provide service logic and support applications at their network server devices.
With the paradigm discussed above relative to FIGS. 10 and 11, it is currently the case that many of the application service providers also find it difficult to provide and support new emerging technologies at the home. That is, service providers are challenged to select a platform that can evolve with their applications. With existing service architectures, the launch of new services compounds complexity to the core network, adding to both capital and operating expenditures.
Thus, as new services come to the fold, often with the requirement of new equipment, e.g. integrated access devices (IADs) for VoIP and set-top boxes for streaming video, the management of the customer premises equipment (both hardware and software) complicates customer support requirements. Managing the home network environment can be an inhibitor to the adoption of new services, both from the user perspective and from the perspective of management by the service providers.
A need exists for a new paradigm, with improved convenience for the user and easier management for the application service provider. In that regard, it would be desirable to provide an arrangement in which one or more aspects of application service(s) facilitated by gateway devices within the user premises are centrally managed.
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A process for producing unsaturated aldehydes and then unsaturated acids from olefins is a typical example of catalytic vapor phase oxidation.
To perform the partial oxidation of olefins, a multimetal oxide containing molybdenum and bismuth or vanadium or a mixture thereof is used as a catalyst. Typically, the partial oxidation of olefins may be exemplified by a process for producing (meth)acrolein and then (meth)acrylic acid by oxidizing propylene or isobutylene, a process for producing phthalic anhydride by oxidizing naphthalene or ortho-xylene or a process for producing maleic anhydride by partially oxidizing benzene, butylene or butadiene.
Generally, propylene or isobutylene is subjected to two-step catalytic vapor phase partial oxidation to form (meth)acrylic acid as a final product. More particularly, in the first step, propylene or isobutylene is oxidized by oxygen, diluted inert gas, water vapor and an optional amount of catalyst to form (meth)acrolein as a main product. In the second step, (meth)acrolein obtained from the preceding step is oxidized by oxygen, diluted inert gas, water vapor and an optional amount of catalyst to form (meth)acrylic acid. The catalyst used in the first step is a catalyst comprising an oxide and/or a composite oxide based on Mo—Bi, which oxidizes propylene or isobutylene to form (meth)acrolein as a main product. Additionally, a part of (meth)acrolein is further oxidized on the same catalyst to form (meth)acrylic acid partially. The catalyst used in the second step is a catalyst comprising an oxide and/or a composite oxide based on Mo—V, which oxidizes (meth)acrolein-containing mixed gas produced in the first step, particularly (meth)acrolein, to form (meth)acrylic acid as a main product.
Reactors for carrying out the above process are realized in such a manner that each of the above two steps are implemented in one system or in two different systems (see U.S. Pat. No. 4,256,783).
Generally, (meth)acrylic acid is reacted with alcohol, to form (meth)acrylate, which is used for paints, fiber formula, coating agent of paper. Especially, a high purity of acrylic acid is used as a raw material for a highly hygroscopic resin, and a demand thereof is recently increasing rapidly.
In general, catalytic vapor phase oxidation is implemented as follows. At least one catalyst in the form of granules is packed into reaction tubes, feed gas is supplied to a reactor through the reaction tubes and the feed gas is in contact with the catalyst in the reaction tubes to perform vapor phase oxidation. Reaction heat generated during the reaction is removed by heat transfer with a heat transfer medium, wherein the temperature of the heat transfer medium is maintained at a predetermined temperature. Particularly, the heat transfer medium for heat exchange is provided on the outer surface of the catalytic tubes to perform heat transfer. A reaction product mixture containing a desired product is collected via a duct and then sent to a purification step. Generally, catalytic vapor phase oxidation is a highly exothermic reaction. Therefore, it is very important to control the reaction temperature in a specific range and to downsize hot spots in the reaction zone.
Vapor phase partial oxidation for producing unsaturated acids from unsaturated aldehydes is an exothermic reaction. Therefore, it has a problem in that a hot spot (a point whose temperature is abnormally high) is generated in the reactor. Such hot spots show a relatively high temperature compared to other parts of the reactor. Accordingly, in hot spots, complete oxidation proceeds rather than partial oxidation, thereby increasing by-products such as COx and decreasing the yield of unsaturated acids. Additionally, excessive heat generated in a hot spot causes migration or sublimation of molybdenum that is a main element of the catalyst, resulting in deposition of molybdenum in a catalytic layer and pressure drop in the catalytic layer, degradation of catalytic activity and in shortening of the lifetime of the catalyst. Therefore, yield of unsaturated acid decreases.
Generally, various methods are known in order to control the excessive heat at a hot spot in a catalytic reaction accompanied with heat generation. Such methods include a method for reducing the amount of feed gas to decrease the space velocity and a method of using a reaction tube having a relatively small inner diameter. However, when the space velocity decreases, it is not possible to obtain high productivity in an industrial scale. When the inner diameter of a reaction tube decreases, it is difficult to manufacture the reactor. Moreover, in the latter case, there are disadvantages of economically unfavorable high cost needed for manufacturing the reactor, and increased time and labor needed for packing a catalyst. For these reasons, there has been a continuous need for and research into a method for producing unsaturated aldehydes and/or unsaturated fatty acids with high yield and high productivity by using a catalyst stably for a long time, while avoiding the above problems according to the known methods.
For example, Such methods include a method for packing a catalytic bed by controlling the volume of catalyst in such a manner that the volume gradually decreases from the inlet to the outlet(Japanese Laid-Open Patent No. Hei9-241209); a method for packing a catalytic bed by controlling the volume of catalyst particle in such a manner that the volume gradually decreases from the inlet to the outlet; a method for preparing acrylic acid by multistage-packing with catalysts having different activities; a method of dividing inside of a reaction tube into a plurality of reaction zones and packing each catalyst therein; a method for packing a catalytic bed by controlling the activity of catalyst in such a manner that the activity gradually increases from the inlet to the outlet(Japanese Laid-Open Patent No. 2000-336060); a method for packing a catalytic bed by controlling the amount of catalyst supported on carrier in such a manner that the activity gradually increases from the inlet to the outlet(US No. 2000-336060); a method for packing a catalytic bed wherein a first reaction zone most adjacent to the inlet is packed with the catalyst having higher activity than that of the second reaction zone adjacent thereto and then the catalytic bed from second reaction zone is packed by controlling the activity of catalyst in such a manner that the activity gradually increases from the inlet to the outlet(Japanese Laid-Open Patent No. 2001-112617). However, the above mentioned methods for minimizing degradation of catalyst and suppressing side reactions by decreasing the temperatures of hot spots are not fully effective to solve the above described problems.
Therefore, there is a continuous need for a method for minimizing degradation of catalyst and side reactions caused by extreme heat generation at a hot spot generated during the catalytic reaction.
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This invention relates generally to sewing machines for sewing quilts, comforters and analogous articles and, more particularly, is directed to a sewing machine having a rotatable and axially movable cylindrically-shaped frame for holding the fabric.
Because of the large size of quilts, comforters and the like, it is difficult to sew patterns thereon. Further, apparatus for sewing the same must occupy a substantial amount of space because of the large size of quilts and comforters, thereby rendering such apparatus inefficient and space consuming.
In order to overcome some of the disadvantages of conventional apparatus, a sewing machine for sewing quilts, comforters and the like has been designed with a substantially cylindrical frame which is rotatable and axially movable on a base and which can expand or contract its lengthwise dimension. Examples of such sewing machines are found in U.S. Pat. Nos. 351,468; 447,794; 448,253; 456,726; 467,138; 1,937,491; 1,946,868; and 2,377,951.
For example, U.S. Pat. No. 1,937,491 generally discloses a rotatable quilting machine having a substantially cylindrical frame axially movable along a base by pulleys which ride upon a central sleeve of the base and by pulleys which cooperate with an upper T-rail of the base. The frame is manually moved along the base by the operator.
The length of the frame is also manually adjustable by adjustable collars, and the frame is rotatably mounted upon the aforementioned central sleeve and manually rotated by raising or lowering of a bar by the operator.
U.S. Pat. No. 1,946,868 discloses a similar arrangement. However, a first rod extends from one end and includes internal screw threads and a second rod extends from the opposite end and is screw-threadedly received within the first rod. A crank handle rotates one of the rods to move the outer rings of the cylindrical frame closer together or further apart.
U.S. Pat. No. 2,377,951 expands on the previous Patent by providing a plurality of such screw-threaded telescoping members. In addition, drive sprockets are provided at the ends of the screw-threaded members at each end of the frame, and a chain passes over the drive sprockets and various idler sprockets. By means of a wrench which can be placed on a non-circular portion of one of the screw-threaded shafts for rotating the same, all of the screw-threaded shafts at the same end of the frame are rotated by means of the chain drive.
Various other ones of the Patents, such as U.S. Pat. No. 467,138 discloses a rotatable drive mechanism in which the outer rings are provided with gear teeth. Through suitable gearing and a manual crank wheel, the frame can be rotated about a central shaft. See also U.S. Pat. No. 448,253.
As to the axial movement of the frame, U.S. Pat. No. 456,726 discloses the use of two cams which coact with projections to provide side-to-side movement of the carriage in a specific pattern.
With all of the above patents, however, the arrangements that are provided for rotating and axially moving the frame are relatively complicated and consume unnecessary space. In addition, there are no automatic means, such as motor means or the like, for controlling rotation, axial movement and elongation of the frame.
In the above discussed patents, the fabric of the quilt or comforter is secured at opposite ends about the substantially cylindrical frame by means of clamping fingers or the like which are manually set. See, for example, U.S. Pat. No. 1,937,491. However, the securement of the fabric to the frame is time consuming and tedious, and therefore inefficient.
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One type of isocyanate coating is made from isocyanate-terminated adducts or prepolymers cured with a second component as a catalyst. Crosslinking is assumed to occur through the formation of substituted urea groups by reaction of the terminal NCO groups with the moisture in the air as well as through the formation of biuret and allophanate linkages. The latter crosslinks may be formed by the catalyzed reaction of the isocyanate groups with urea and urethane linkage.
Two component isocyanate base coatings include the reaction of isocyanates with hydroxy groups cured with the presence of an organometallic catalyst or the use of isocyanate groups catalyzed by organic amines preferably tertiary amines.
Certain high molecular weight amines have been suggested as catalysts for isocyanates in the presence of polyol in the preparation of urethane foam (e.g., see U.S. Pat. Nos. 3,428,708 and 3,448,065).
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Down-converters in wireless receivers perform a transformation of a radio frequency (RF) signal into a baseband signal centered at zero frequency. In high performance equipment, digital down-converters are used, making it necessary to convert an analog RF signal into a digital signal. Typically, a high-speed ADC is used because of the high frequency of the RF signal.
High speed analog to digital converters are generally built as composite ADCs that consist of a number of time interleaved sub-ADCs with a common input and sequential timing. In general, the amplitude frequency response and phase frequency response of the different sub-ADCs are not identical, resulting in specific signal distortions, for example, the appearance of spurious frequency components. To prevent these distortions, equalization of the responses of the sub-ADCs is used (see, for example, U.S. Pat. No. 7,408,495).
A block diagram of a conventional digital down-converter with an equalizer, is shown in FIG. 1. An RF signal, applied to the input of a composite ADC 1, is transformed into a digital signal. The misalignment of the frequency responses of the sub-ADCs of ADC 1, is corrected by an equalizer 2. An I/Q demodulator is constructed using two mixers 3 and 5 with a common local oscillator frequency ωLO and with a phase difference of 90 degrees. Low pass filters 4 and 6 produce two outputs labeled In-Phase (I) and Quadrature (Q).
The equalizer 2 and the low pass filters (LPFs) 4 and 6 in the block diagram of FIG. 1 are built usually as conventional finite impulse response (FIR) filters. The most resource-consuming components of such FIR filter are multipliers. Because of the difference between the RF signal frequency (typically several GHz) and the frequency of operation of present-day FPGAs (up to 200-250 MHz), each multiplication in the FIR filters is carried out by a group of multipliers connected in parallel. The required number of multipliers becomes the main reason that makes it necessary to use in the equalizer design, more FPGAs and/or FPGAs of larger size or, in some cases, makes the real time equalizer design impossible.
This problem was solved (partially at least) in U.S. Pat. No. 9,148,162; U.S. Pat. No. 9,634,679; and U.S. Pat. No. 9,641,191. In those patents, it was proposed there to combine equalization with down conversion, performing equalization in I and Q branches of the down converter separately. Furthermore, the cascade connected units in each branch (equalizer, low pass filter and, maybe, mixer) are replaced by a single finite impulse response (FIR) filter. A decimator is placed inside the FIR before the multipliers. In that way the frequency of each multiplication in the down converter is lowered and the number of required multipliers is reduced significantly.
That solution, which is proposed in the above-cited patents, makes it possible for the first time to design a digital down converter which operates in a real time mode. However, the full potential for reduction in the number of multipliers is not completely exploited. The equalizers in the above-cited patents are required to correct the frequency responses from zero frequency up to the Nyquist frequency, whereas the bandwidth of the processed signals is much narrower. When the bandwidth of the equalizer operation is made narrower in these prior art approaches, the number of taps in the equalizers is cut down proportionally, with the required number of multipliers being reduced as much. The bandwidth of the equalizer operation may be reduced by placing it after the low pass filters, but since samples at the filter outputs are formed as linear combinations of samples produced by all sub-ADCs, the correction of misalignment of frequency responses in this situation becomes impossible.
A number of approaches for correcting misalignment of frequency responses in digital down-converters have been proposed for simplified composite ADCs consisting of two sub-ADCs. For example, U.S. Pat. No. 9,628,097 by Johannson “Methods and devices for handling channel mismatches of an I/Q down-converted signal and a two-channel TI_ADC” describes procedure for compensating ADC mismatch based on I/Q down-converted signals. However, this procedure requires the generation intermediate “service” signals with over-sampling, and does not address overall equalization required for digital down-conversion. A journal paper by Singh, Epp et. al, “Analysis, Blind Identification, and Correction of Frequency Response Mismatch in Two-Channel Time-Interleaved ADCs' (IEEE Transactions On Microwave Theory and Techniques, Vol. 63, No. 5, May 2015), describes theoretical spectra distortions for an ADC with time-interleaved sub-ADCs, and proposed to use blind mismatch identification of two ADC responses and adaptive filtering for frequency response correction. The method of adaptive equalization is not applicable to real time down-conversion applications since adaptive equalization may have significant time lag and convergence issues, and may require transmission of special pilot signals. Moreover, the adaptive equalization method depends on a transmitted signal and is not applicable for test and measurement applications. A calibrated reference high speed ADC with down-conversion is a requirement for characterization of RF equipment, such as analog up- and down-converters, filters and transmission/receiver antennas.
An object of the present technology is provide a digital down-converter, where the bandwidth of equalizer operation is equal to the bandwidth of the processed signals, while at the same time to correcting misalignment of the frequency responses of the sub-ADCs of a composite ADC.
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This invention relates to bar code scanning, and in particular to techniques for combining, or stitching, partial scans.
A bar code symbol is a coded pattern of indicia comprising a series of bars and spaces having different light reflecting characteristics. Bar code scanning systems electro-optically transform the indicia into electrical signals, which are decoded into alphanumerical characters. Characters are typically represented in digital form and are provided as an input to a data processing system for applications, such as point-of-sale processing and inventory control. Scanning systems of this general type have been disclosed, for example, in U.S. Pat. Nos. 4,251,798; 4,369,361; 4,387,297; 4,409,470; 4,760,248; and 4,896,026, all of which have been assigned to the same assignee as the instant application.
Bar code symbols are formed from a series of bars and spaces, called elements, which are typically rectangular in shape and have a variety of possible widths. The specific arrangement of elements defines the character represented according to a set of rules and definitions. To encode a desired sequence of characters, groups of elements are concatenated to form a bar code symbol, with each character of the message represented by a corresponding group of elements. In some symbologies a "start" and "stop" character is used to indicate where the bar code begins and ends. There are a number of symbologies in use, e.g., UPC/EAN, Code 39, Code 128, Codabar, and Interleaved 2 of 5.
In typical scanning systems, a light source, such as a laser or laser diode, produces a beam which is directed by a lens or similar optical components along a light path toward a target that includes a bar code symbol on the surface. The beam produces a spot on the target. To scan with a laser system, the spot may be moved with an oscillating motor to produce a line or series of lines across the symbol. A portion of the light that is reflected off the symbol is detected by a sensor which may be positioned in the scanner. The sensor converts the reflected light into an electrical signal which is converted to a digital representation by electronic circuitry. For example, an analog electrical signal from the photodetector may be converted into a pulse width modulated digital signal, with pulse widths corresponding to the physical widths of the bars and spaces.
The decoder receives the pulse width modulated digital signal from the scanner, and attempts to decode the scan. If the start and stop characters and all of the characters between them are decoded successfully, the decoding process is finished. Otherwise, the decoder receives a next scan and attempts to decode it. Each attempt is based on the signal received during a single scan. The process continues until a scan is completely decoded or until no more scans are available.
A scan line or series of scan lines may not always entirely cross the bar code symbol. For example, a scanner may be in a fixed position next to a conveyor with containers, each of which has a bar code symbol printed on a label. If the label is skewed with respect to the scan line, there may be no single scan line which includes both the start and stop characters. These incomplete scan lines, called fragments, were discarded until techniques were developed to stitch or combine the fragments together, so that the decoding process can be completed.
Several basic techniques have been employed to combined fragments. One technique, known as block decoding, involves combining predefined regions or blocks in a number of scans. For example, a symbology such as UPC has start, stop, and center characters. If one fragment includes a start and a center, and another fragment includes a center and stop, these two "blocks" can be combined to form a complete scan.
In another method, a system checks fragments for corresponding portions, and stitches by superimposing. For example, the widths of elements can be measured in clock pulses for two fragments. These widths may be converted to a binary representation of widths or of ratios of widths between successive elements. The pulse count or other representation of the width of an element in one scan is compared to the width of an element in another scan. If these are the same or sufficiently similar, adjacent elements are compared. If a group of elements of a certain length are the same, the two groups of elements are considered to be corresponding, and the two fragments are stitched by superimposing the common portions.
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This invention relates to refrigerated display cases, and closed display cases as of the deli service type.
Closed refrigerated display cases, because of the cool air inside the case, tend to collect condensed moisture on the glass window used to display the food products, i.e., the windows tend to "sweat." Condensation moisture on the inner surface can be prevented by circulating refrigerated air within the case, the moisture being picked up and condensed on the refrigeration coil used to cool the air. As to the exterior surface of the display window, the typical technique for preventing/removing condensation is to warm the window with added heat. This can be heat applied directly to the window, or heat applied to a portion of the flowing air in the cabinet, causing the heated air portion to flow across the window inner surface to warm the window. An example of the use of a heater placed in the air stream for this purpose is shown in U.S. Pat. No. 4,750,335. While application of heat is effective, it requires use of extra energy to create the heat, and then more energy for extra cooling action to again cool the heated air for preventing unwanted temperature rise within the cabinet display area and the stored food.
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Network devices, such as network switches, are used to transport network packets through computer networks. Network devices can receive network packets and, based on information in each network packet, such as an address, forward the network packet to an appropriate different network device. Modern network devices can forward a large number of packets per second and, while forwarding the packets, collect statistical information. It is desirable to collect statistical information corresponding to the forwarding of the network packets to, for example, identify congestion, identify errors, and/or to generally monitor network health. Collecting, storing, and processing this statistical information can be burdensome for network devices. Thus, there is a need for improvement in the field of network devices.
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(a) Field of the Invention
The present invention relates to a magnetic bubble memory module and particularly to a magnetic bubble memory module which is suitable for thinning and miniaturizing its body lowering consumption and ameliorating efficiency of composition.
(b) Description of the Prior Art
The magnetic bubble memory module realized in these years has the structure wherein an x-coil and a Y-coil for generating a revolving magnetic field which are respectively composed of square solenoid coils having non-symmetric structures with each other are respectively inserted to E-like substrates made of ceramic, synthetic resin or the like mounting a magnetic bubble memory chip and are arranged at a right angle with each other. The X-coil and the Y-coil must be provided around not only a magnetic bubble memory chip but also a substrate which is far larger than the chip. Thus, the length from one end of each coil to the other end thereof is made longer and thus the driving voltage and the power consumption are made larger. Further, the X-coil and the Y-coil supply a uniform and stable in-plane revolving magnetic field to the magnetic bubble memory chips and thus respectively require a uniform inductor balance. Thus, these coil forms are respectively required to have non-symmetric structures which are different from each other and to have large structures. Moreover, these coils respectively have the structure wherein there are arranged on the outside surfaces of the X-coil and the Y-coil a pair of permanent magnet plates for supplying vertial bias magnetic fields to each magnetic bubble memory chip and the plates for homogenizing their magnetic fields and these peripheral portions are covered with resin molds. Accordingly, their lamination thicknesses in the vertical direction are made larger and this enlargement has been made to be an obstacle to requirements for thinning and miniaturizing a magnetic bubble memory module.
As the closest prior art to the present invention of which the present inventors are aware, it is possible to cite the invention of U.S. Pat. No. 4,165,535. This specification discloses a structure of a picture frame core surrounding a chip and a conducting box for reflecting a magnetic field completely surrounding the core and the chip. However, it does not disclose more concrete structure than the above any more. For example, it is theoretically impossible to carry out electrical connection to a chip completely surrounded by a conductor case from the outside of the conductor case without short-circuitting with the conductor case. Further, it does not clearly disclose the method of mounting a permanent magnet, a plate for homogenizing a magnetic field, a bias coil and the like. Accordingly, the disclosure is apparently insufficient to be considered as a hint for trying to realize the present invention. Namely, as a result, the embodiment of the present invention just happens to coincide with the disclosure of the above-stated specification in the respect of employing a picture frame core for the embodiment of the present invention.
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1. Field of the Invention
The present invention relates to a machine for working on a ballast bed supporting a track, which comprises a machine frame, undercarriages supporting the machine frame on the track, a ballast storage receptacle on the machine frame, and a suction arrangement on the machine frame, the suction arrangement comprising a suction unit and a suction conduit connected to the suction unit, the suction conduit terminating in a vertically and transversely adjustable suction snout defining a suction opening for aspirating ballast into the ballast storage receptacle.
2. Description of the Prior Art
One type of such a machine has been described in German utility model No. 8,236,650, published Jun. 30, 1983. This machine has a suction snout projecting from the machine frame and defining a suction opening for aspirating ballast from the track bed and a suction conduit for conveying the ballast to a ballast storage receptacle. After the aspirated ballast has been cleaned, the cleaned ballast is returned to the track bed by a transversely extending conveyor band.
Another type of such a machine is disclosed in German patent No. 2,136,306, wherein the suction snout projecting from the machine frame carries a suction nozzle with vibrators for loosening the ballast to be aspirated. An auxiliary port is arranged adjacent the suction opening and is connected to the input opening of a suction unit to enhance the aspirating capacity.
U.S. Pat. No. 4,938,239 discloses a mobile machine for cleaning the surface of a track bed by aspiration. A suction head extends over the entire width of the track bed and is connected to a suction unit. The suction head has a compressed air supply nozzle in the suction opening for causing turbulence in the surface dirt and this nozzle is connected to the output opening of the suction unit. Similar machines incorporating such a compressed air/suction system are disclosed in German patent No. 3,318,756 and Austrian patent No. 312,028.
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Known stone retrieval devices typically have baskets that are constructed by joining multiple legs together at a base of the basket and at a distal end or tip of the basket such that a “cage” is formed. At the distal tip, the individual legs are joined by soldering, adhesives, etc. such that a protruding tip results. This protrusion or outward projection at the distal end of the basket can poke tissue and cause tissue trauma. In general, the tips or ends of known baskets protrude outward and thus can cause damage by poking or piercing tissue. Also, the protruding tips of known baskets generally do not permit access to or intimate contact with certain areas within the body such as “pockets,” and thus stones residing in such areas are difficult or impossible to retrieve with known baskets.
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1. Field of the Invention
The present invention relates to a print output system, a print control apparatus and a print control method which are configured to control print output by a plurality of printing apparatuses.
2. Description of the Related Art
A conventional printing apparatus such as a digital copying machine, a laser beam printer (LBP), a facsimile apparatus is connected to a network and printout is executed by sending documents or images from a personal computer connected to the network to the printing apparatus. The printing apparatus can be set so that when it is not manipulated and operated within a predetermined time, for example, on the operation panel, power supply is stopped to a fixing device or the like which has high power supply, and the printing apparatus transits to a sleep state (power saving mode) which is configured to suppress power consumption for the overall apparatus.
In a conventional print output system, since the conditions for shifting to power saving mode vary depending on each apparatus, comprehensive power saving management of a printing apparatus connected to a specified network has been difficult. For example, it is assumed that there are two printers connected to a plurality of personal computers, one printer is operating and the other printer is in power saving mode. When a print output signal is output from another personal computer, normally, the printer in power saving mode is operated. The image processing apparatus proposed in Japanese Patent Application Laid-Open No. 2001-197297 determines a sleep condition for a printer, and when print output is not urgent, waits for completion of the current print job (JOB) performed by the currently operating printer. Thereafter the plurality of printing apparatuses connected to the network is controlled to execute new printing jobs.
Although the conventional technique takes the state of the printing apparatus into account, the characteristics of the printing apparatus are not considered. Thus when a plurality of printing apparatuses with mutually different characteristics are present on a network, there is the situation that overall power consumption actually increases. For example, currently, a fixing device constituting a digital copying machine employs the fixing method illustrated in FIG. 3A or the fixing method illustrated in FIG. 3B as described hereafter. The fixing method in FIG. 3A is of a roller type and the fixing method in FIG. 3B is of an on-demand type.
FIG. 13 illustrates the characteristics of the fixing device and the relationship between temperature and printing for each fixing method. FIG. 13A illustrates the characteristics of an on-demand type and a roller type. Generally, a roller type has high power consumption and a high printing speed. An on-demand type has low power consumption and a low printing speed. FIG. 13B conceptually illustrates the relationship between printing and the temperature of a fixing device in a digital copying machine based on mutually different fixing methods. In contrast to a digital printing apparatus provided with a fixing device on the basis of an on-demand type fixing method, a digital copying machine provided with a fixing device on the basis of a roller-type fixing method is maintained at high temperature (standby state), which results in high power consumption even after execution of printing. If a new print job is started again within the period from standby to a low-temperature state (sleep state), the high-temperature state further continues, which results in high power consumption. Therefore when an on-demand type and a roller-type digital copying machine are both present in a print output system, in order to suppress power consumption, the characteristics of the printing apparatuses is to be sufficiently considered.
Further, the conventional technique does not consider an operation state or operation rate in addition to characteristics such as the fixing method of the printing apparatus when determining an apparatus to execute print output. Thus in the conventional technique, for example, there is a situation such as an increase in the power consumption of the overall system resulting from biased selection of a roller-type printing apparatus, which has high power consumption as the apparatus to execute print output. A further situation is that printing efficiency of the overall system cannot be increased due to biased selection of an on-demand type printing apparatus which has low power consumption but a slow printing speed as the apparatus to execute print output.
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1. Field of the Invention
Exemplary aspects of the present invention generally relate to a packaging container, and more particularly, to a packaging container having at least one opening from which an object can be inserted.
2. Discussion of the Background
Conventionally, when transporting an object, for example office automation (OA) equipment, various kinds of objects are packaged together with the OA equipment. Such, accompanying objects include, for example, an operating manual, a CD for installation of a program, a memory card, optional parts, and so forth.
Such objects are stored in a packaging container made of paper and are enclosed in a packaging container for storing the OA equipment main body.
The packaging container may be made as a single piece by cutting out a flat blank of coated board or cardboard, and the cutout is folded. The following packaging containers of this type have been proposed.
In Registration of Utility Model No. 3094232, fold lines are formed at both sides of an envelope in a vertical direction. The both sides are folded in accordance with the height of an object to be stored, and are adhered so that the strength is enhanced.
The cardboard envelope is formed such that a cardboard sheet with sealing flaps and adhesive flaps is folded while the adhesive flaps are adhered. On the bottom of the envelope, the fold lines are formed along the width direction. At both ends, the fold lines are vertically formed. A plurality of the vertical fold lines is provided at both sides.
In Registration of Utility Model No. 3110361, an envelope provided with a shock absorbing material is proposed. In other words, inside the envelope made of paper with a flap, there are ruled straight lines equally spaced between protruding portions, thereby forming a wave-like shape.
The shock absorbing sheet made of paper having the wave-like shape is folded in half along a designated ruled line for folding in half, such that the protruding portions face inside. The protruding portions at both ends of the shock absorbing sheet are crushed so as to attach to an opening rim of the envelope.
In Japanese Published Unexamined Application H11-292057, a sheet of cardboard folded to form a box-like packaging container is proposed.
According to the related art, a cut is provided in a folded flap at the end portion of an open side of a cover. A lock flap is inserted into the cut in the folded flap of the cover from the box main body so as to lock the cover.
In such a cardboard packaging container, a cut piece is formed on the lock flap at a position where a finger is placed.
In Japanese Published Unexamined Application S60-23143, a reinforcing structure for a packaging box is proposed. Reinforcing frames are provided in the packaging box so that even if a plurality of packaging boxes is stacked on one another, the packaging boxes are not damaged.
A plurality of holes is provided on the bottom of the packaging box. The packaging box is placed on a base made of copper, and the reinforcing frames disposed inside the packaging box are inserted in the holes of the base, thereby supporting the packaging box on the base.
In Japanese Published Unexamined Application 2005-178819, a container filled with objects stored therein is shrinkable and packaged by a box-shape or triangular packaging box is proposed.
After the stored objects are removed, the packaging box is depressed so that the packaging box is flattened for easier collection.
A first wall and a second wall opposite the first wall press the outer surface of the shrinkable container holding the object while the container is fixed to the packaging box by a frictional force.
Objects to be stored in the packaging container come in various thicknesses, sizes, and shapes, etc. That is, some objects are relatively thin, such as an instruction manual and a CD, while other objects are relatively thick, such as a memory card and optional parts.
However, the related art packaging containers described above may accommodate only a single form of object. Consequently, different packaging boxes which may accommodate various thicknesses are needed.
Therefore, in reality, when storing an object that is relatively thin, an envelope is used, and when storing an object that is relatively thick, a box-type packaging container is needed.
Envelopes are normally thin, and thus load efficiency is enhanced. On the other hand, stiffness is most likely low. Consequently, the envelopes are not suitable for packaging fragile objects.
At the same time, when using a box-type packaging container, a packaged object may not be damaged, because the six sides of the box-type packaging container are closed so that stiffness can be secured.
However, as described above, the thickness, volume, stiffness, and shapes of objects may vary. As a result, the cost for manufacturing the designated packaging containers becomes expensive.
In order to accommodate an object having a flexible shape, the above-described related art packaging container having a shrinkable shape has been proposed (Japanese Published Unexamined Application 2005-178819).
However, according to the related art, the object to be stored is the same, with the packaging container accommodating particular changes in the shape of the same object.
Furthermore, such packaging container does not have a structure that secures the stiffness of the container itself. Thus, it is not suitable for transportation of an object while maintaining the shape of the packaging container.
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Head supports of the aforedescribed type are known. They have, however, the disadvantage that the frictional retention of the relatively angularly desplaceable parts that permit the swinging or tilting movement have different degrees of clamping which may result from different manufacturing tolerances or otherwise and/or because the material frictionally engaging the same may be too soft or pliable and, with time, tends to become flowable. As a consequence, a sufficient frictional clamping of relatively movable pivotal parts cannot be ensured and it is not possible to provide an angular or pivotal adjustment of the headrest which can retain its position. As a consequence, the headrest may swing involuntarily out of a preset position in an undesirable manner.
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A goal of the Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) program is to develop new technology, new architecture and new methods for settings and configurations in wireless communication systems in order to improve spectral efficiency, reduce latency and better utilize the radio resource to bring faster user experiences and richer applications and services to users with lower costs.
Wireless communication systems usually require feedback signaling to enable uplink and downlink communications. For example, hybrid automatic retransmission request (HARQ) enablement requires acknowledge/non-acknowledge (ACK/NACK) feedback. Adaptive modulation and coding (AMC) requires channel quality index (CQI) feedback from a receiver. Multiple Input/Multiple Output (MIMO) systems or precoding requires rank and/or precoding matrix Index (PMI) feedback from a receiver. Typically, this type of feedback signaling is protected by coding and the signaling does not have error checking or detection capabilities. However, efficient signaling is essential to an evolved universal mobile telephone system (UMTS) terrestrial radio access network (E-UTRAN). Adding error check (EC) and error detection capability to the feedback control signaling makes more advanced applications possible. Error check (EC) and error detection capability can enable advanced signaling schemes, enhanced MIMO link performance, reduced system overhead, and increased system capacity.
An example of an application that may require error detection and checking capability for feedback control signaling is the preceding information validation. The precoding information validation is used to inform a WTRU about the precoding information that is used at an e Node B so that the effective channel seen by the WTRU that contains precoding effects can be reconstructed by the WTRU. This is required for accurate data detection for MIMO systems using precoding, beam forming or the like.
A wireless transmit receive unit (WTRU) may feedback a precoding matrix index (PMI) or antenna weight to a base station (BS) or an e Node B (eNB). To inform a WTRU of the precoding matrices used at an eNB, the eNB may send a validation message to the WTRU. Each matrix that the WTRU signals as feedback to the eNB may be denoted by PMI_j1, PMI_j2 . . . PMI_jN, where N is a integer value equal to the total number of matrices. The eNB may send a validation message containing information about N PMIs denoted by PMI_k1, PMI_k2 . . . PMI_kN to the WTRU.
Each PMI may be represented by L bits. The value of L depends upon the multiple input/multiple output (MIMO) antenna configuration and codebook sizes.
Communication resources may be assigned to a WTRU. A resource block (RB) consists of M subcarriers, for example M=12, where M is a positive integer. A resource block group (RBG) or sub-band may include N_RB RBs, where N_RB may equal, for example, 2, 4, 5, 6, 10, 25 or larger. A system bandwidth can have one or more RBGs or sub-bands depending on the size of bandwidth and value of N_RB per RBG or sub-band.
A WTRU may feed back one PMI for each RBG or sub-band that is configured to it. The terms RBG and sub-band may be used interchangeably. N RBGs, where N.ltoreq.N_RBG, can be configured to or selected by a WTRU for feedback and reporting purpose. If N RBGs or sub-bands are configured to or selected by a WTRU, then the WTRU feeds back N PMIs to the eNB. The eNB may send the validation message consisting of N PMIs back to the WTRU.
Let N_PMI be a number of bits that represents a PMI. The total number of bits for the WTRU PMI feedback is N.times.N_PMI. The maximum number of bits for WTRU PMI feedback is N_RBG.times.N_PMI bits per feedback instance. When a straightforward precoding validation scheme is used, the maximum number of bits for PMI validation message is N_RBG.times.N_PMI bits per validation message.
Table 1 shows a number of bits for WTRU PMI feedback and signaling with the assumption that N_PMI=5 bits. The numbers are summarized for 5, 10 and 20 MHz bandwidth. The second row, N_RB, is the number of RBs per RBG or sub-band, which is in a range of 2 to 100 for 20 MHz. The third row, N_RBG per band, is the number of RBGs or sub-bands per 5, 10 or 20 MHz. The value of N_RBG is in a range from one to fifty. The fourth row is the total number of bits used for WTRU PMI feedback signaling per feedback instance. This is for frequency selective precoding feedback or multiple PMI feedback
5 MHz10 MHz20 MHz(300 subcarriers)(600 subcarriers)(1200 subcarriers)N_RB per RBG2510252510255025102550100N_RBG per band135312510521502010421Max # of bits652515512550251052501005020105for PMI feedbackper feedbackMax # of bits652515512550251052501005020105for PMI signalingper messageAssume 12 subcarriers per RB.N_RB: Number of resource blocks.N_RBG: Number of frequency RB groups.N_PMI: Number of bits to represent a PMI.Max number of bits for WTRU PMI feedback = N_RBG × N_PMI bits.Max number of bits for eNB validation message = N_RBG × N_PMI bits.
PMI feedback and PMI validation may require over 250 bits per feedback instance and per validation message as shown in the above table.
Feedback error significantly degrades the link and system performance. It would be desirable for feedback bits to be protected with error checking (e.g., channel coding). Furthermore, knowing whether there is an error in a feedback signal improves system performance such as link performance, because the erroneous feedback information can be avoided. Furthermore, knowing whether there is error in the feedback signaling enables the use of advanced signaling schemes or applications such as the precoding confirmation and indication schemes. Precoding confirmation can be sent to confirm the correctness of feedback signaling if there is no error in the feedback signaling.
A single bit or bit sequence may be used for precoding confirmation and may be sufficient for some applications. The use of advanced signaling such as precoding validation using confirmation significantly reduces the signaling overhead. Therefore error checking and detection is desirable.
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Hydrochloride of 2-amino-2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]-ethyl]-1,3-propanediol (hereunder referred to as the “compound of the present invention”) is a compound having a substituted diaryl sulfide structure and having an excellent immunosuppressive action and there has been reported that the compound of the present invention is effective for the treatment of the autoimmune diseases such as chronic rheumatoid arthritis (see Patent Document 1).
Patent Document 1 discloses a method for the crystallization of the compound of the present invention which comprises the step of crystallizing the compound through the addition of an ethyl acetate solution of hydrochloric acid to a methanol solution of the compound (see Example 36). In addition, Patent Document 2 discloses a method for the crystallization of the compound of the present invention, which comprises the steps of adding a 6 mole/L of hydrochloric acid to a solution of the compound of the present invention in ethyl alcohol and then adding ethyl acetate to the resulting solution (see Example 4). These methods are ones in which hydrochloric acid is dissolved in ethyl acetate and then the resulting hydrochloric acid solution is added to a solution of the compound of the present invention in an alcohol; or hydrochloric acid is added to an alcoholic solution of the compound of the present invention and then ethyl acetate is added to the resulting mixture.
Patent Document 1: WO 03/029205, Pamphlet;
Patent Document 2: WO 06/041019, Pamphlet.
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Recent advances in video monitor technology have resulted in the development of large format, high quality video displays that are capable of displaying multiple video signals simultaneously. In television studios and other locations where many different video sources must be monitored, these video displays have begun to displace traditional individual monitors that displayed a single video source to which they were physically coupled.
Modern signal processing equipment allows video and other data to be routed to different display monitors, however, this equipment can still require that for a particular signal to be used in multiple locations on multiple display devices it must be replicated and coupled to equipment in the different locations. This results in excessive cabling requirements, multiple signal regeneration and replication stages, and can result in degraded signals and multiple failure points within the signal path.
There is a need for an improved efficient system for receiving various input signals, including video, audio and data signals, formatting the received signals and routing the formatted signals to various output devices.
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In prior art telecommunication switching systems, it is well known to synchronize a central timing unit within the telecommunication switching system to an external link. Indeed, this is commonly done so as to maintain consistent timing throughout a public telecommunication network. In prior art telecommunication systems, this was accomplished by hardwiring timing links from one or more selected external links to the central timing unit. The central timing unit then could select one of the hardwired links to synchronize the internal timing of the central timing unit.
Whereas the prior art telecommunication switching systems did provide a solution, this solution has many problems. The first problem is that the external links to which synchronization was to be performed had to be selected and then, manually hardwired links had to be installed. Because of the cost and complexity of establishing hardwired links, normally only a small set of external links such as two were selected. In addition, the hardwired links had to be duplicated for reliability purposes but if the two duplicated hardwired links should fail, then the central timing unit could not synchronize to that particular external link. In addition, new international standards require that a telecommunication switching system be able to determine which external link is connected to the best timing source and utilize that external link. This means that a prior art telecommunication switching system would have to have hardwired links to each of the external links.
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1. Technical Field
The present invention relates to a printing apparatus in which ink cured by irradiation with light is used. The invention also relates to a method for preventing uneven gloss on an image printed using the printing apparatus.
2. Background Technology
Inkjet printers for discharging ink onto a medium to form an image belong to the class of printing apparatuses. In such of these inject printers, images are printed using light-curable ink that is irradiated with ultraviolet light or other light and cured (for example, refer to Patent Citation 1). In inkjet printers that use such light-curable ink, the occurrence of bleeding (running) caused by combinations of ink droplets can be suppressed by curing the ink droplets discharged on the medium with light.
Japanese Patent Registration No. 4321050 (Patent Citation 1) is an example of the related art.
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Antimicrobial peptides (AMP) form the cornerstone of eukaryotic immunity and provide a first line of defense against breach of the skin and mucosal surfaces by micro-organisms. Examples of natural AMP include the defensin and cathelicidin families of peptides. These AMP are heterogeneous in length, sequence and structure, but common to most is their small size, net cationic charge and amphipathic structure. Small, cationic antimicrobial peptides have also been isolated from many bacteria, fungi, plants, invertebrates and vertebrates and would therefore appear also to play a role in prokaryotic defenses.
Natural AMP exhibit broad-spectrum activity against Gram-positive and Gram-negative bacteria, yeasts, fungi and enveloped viruses. Microbial pathogens do not seem to acquire resistance to these cationic peptides and as such, AMP have been conserved as a vital innate immune host defense molecules through millennia of evolution. It is not surprising therefore that AMP have been implicated as potential targets for therapeutics for a wide range of infections. However, the fact that they are technically challenging and costly to produce in recombinant systems and have potent chemotactic and inflammatory biological functions rules out natural AMP forms for as therapeutics.
In our co-pending application we have shown that linear peptides rich in certain basic residues such as lysine or arginine possess antimicrobial activity, and, in particular, anti-fungal activity. There remains, however, a need for further agents that can be used in the treatment or prevention of microbial infections.
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Integrated circuits (ICs) comprise complex circuit blocks, each circuit block further comprising a plurality of transistors. The transistors are normally constructed on a semiconductor substrate. Metal interconnects couple transistors. Pad structures are formed within the IC to couple the IC to external devices. A pad structure includes a metal pad to facilitate bonding of the IC in a printed-circuit-board (PCB). Within the IC, the metal pad couples to one or more circuits, typically input circuits or output circuits, to facilitate coupling of the external device to the IC. Thus a pad in a first IC couples to a pad in a second IC. Pad structures occupy a significant silicon area as each pad structure includes a metal pad, input or output buffers, electro-static-discharge (ESD) circuits, control circuits, clock circuits, registers, etc. Metal pads itself is very large to facilitate bonding. Thus the pad cost for a given plurality of ICs required in a reference system design is significant. Furthermore as pads couple between IC's, the I/O characteristics are extremely important to interface devices.
Traditionally, integrated circuit (IC) devices such as custom, semi-custom, or application specific integrated circuit (ASIC) devices have been used in electronic products to reduce cost, enhance performance or meet space constraints. However, the design and fabrication of custom or semi-custom ICs can be time consuming and expensive. The customization involves a lengthy design cycle during the product definition phase and high Non Recurring Engineering (NRE) costs during manufacturing phase. Further, should bugs exist in the custom or semi-custom ICs, the design/fabrication cycle has to be repeated, further aggravating the time to market and engineering cost. As a result, ASICs serve only specific applications and are custom built for high volume and low cost applications.
Another type of semi custom device called a Gate Array customizes modular blocks at a reduced NRE cost by synthesizing the design using a software model similar to the ASIC. The missing silicon level design verification results in multiple spins and lengthy design iterations.
In recent years there has been a move away from custom or semi-custom ICs towards field programmable components whose function is determined not when the integrated circuit is fabricated, but by an end user “in the field” prior to use. Off the shelf, generic Programmable Logic Device (PLD) or Field Programmable Gate Array (FPGA) products greatly simplify the design cycle. These products offer user-friendly software to fit custom logic into the device through programmability, and the capability to tweak and optimize designs to optimize silicon performance. The flexibility of this programmability is expensive in terms of silicon real estate, but reduces design cycle and upfront NRE cost to the designer. Most FPGA solutions mandate an external memory (boot-ROM) to store configuration data, thus exacerbating the solution cost. The FPGA to memory interface is via high silicon consuming pad structures.
FPGAs offer the advantages of low non-recurring engineering costs, fast turnaround (designs can be placed and routed on an FPGA in typically a few minutes), and low risk since designs can be easily amended late en in the product design cycle. It is only for high volume production runs that there is a cost benefit in using the more traditional approaches. However, the conversion from an FPGA implementation to an ASIC implementation typically requires a complete redesign. Such redesign is undesirable in that the FPGA design effort is wasted. An ASIC does not require configuration data and does not interface with a boot-ROM.
Compared to PLD and FPGA, an ASIC has hard-wired logic connections, identified during the chip design phase, and need no configuration memory cells. This is a large chip area and cost saving for the ASIC. Smaller ASIC die sizes lead to better performance. A full custom ASIC also has customized logic functions which take less gate counts compared to PLD and FPGA configurations of the same functions. Thus, an ASIC is significantly smaller, faster, cheaper and more reliable than an equivalent gate-count PLD or FPGA. The trade-off is between time-to-market (PLD and FPGA advantage) versus low cost and better reliability (ASIC advantage).
There is no convenient migration path from a PLD or FPGA used as a design verification and prototyping vehicle to the lower die size ASIC. All of the SRAM or Anti-fuse configuration bits and programming circuitry has no value to the ASIC. Programmable module removal from the PLD or FPGA and the ensuing layout and design customization is time consuming with severe timing variations from the original design. The pad structures play a major role in FPGA I/O interface characteristics, and matching those in a design conversion is not a simple exercise.
FIG. 1A shows prior-art arrangement of a first IC 100 coupled to a second IC 101. The first IC 100 includes a first transistor layer 102 having one or more circuit blocks 104. IC 100 includes one or more metal pads 103, each pad coupled to a circuit block such as 104. Typically, metal pad 104 is located substantially above the transistor layer 102. When IC 100 is an FPGA, circuit blocks 104 include I/O blocks, programmable logic blocks, and configuration memory. Data at pad 103 is received by a first circuit block 104 interfacing the pad, and then programmed into memory elements within configuration circuits. Second IC 101 includes a second transistor layer 106 having one or more circuit blocks 108. Each metal pad 107 in IC 101 is coupled to a circuit block such as 108. When IC 101 is a memory device, circuit blocks 107 include I/O blocks, memory arrays, and sense amplifiers. Data received/transmitted at pad 107 is handled by a circuit block 108 interfacing the pad. Thus pads 103 and 107 form a bus structure for data transfer between devices. FIG. 2A shows a second embodiment of prior art device coupling. In FIG. 1B, pads 117 and 113 are first coupled to a common metal trace 120. Both ICs incur a large Si area for I/O's, and have limited pads to connect to each other.
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FIG. 1 is a simplified side cross-sectional view of a portion of a display 10 including a faceplate 20 and a baseplate 21, in accordance with the prior art. FIG. 1 is not drawn to scale. The faceplate 20 includes a transparent viewing screen 22, a transparent conductive layer 24 and a cathodoluminescent layer 26. The transparent viewing screen 22 supports the layers 24 and 26, acts as a viewing surface and forms a hermetically sealed package between the viewing screen 22 and the baseplate 21. The viewing screen 22 may be formed from glass. The transparent conductive layer 24 may be formed from indium tin oxide. The cathodoluminescent layer 26 may be segmented into pixels yielding different colors to provide a color display 10. Materials useful as cathodoluminescent materials in the cathodoluminescent layer 26 include Y2O3:Eu (red, phosphor P-56), Y3(Al, Ga)5O12:Tb (green, phosphor P-53) and Y2(SiO5):Ce (blue, phosphor P-47) available from Osram Sylvania of Towanda Pa. or from Nichia of Japan.
The baseplate 21 includes emitters 30 formed on a surface of a substrate 32. The substrate 32 is coated with a dielectric layer 34 that is formed, in accordance with the prior art, by deposition of silicon dioxide via a conventional TEOS process. The dielectric layer 34 is formed to have a thickness that is approximately equal to or just less than a height of the emitters 30. This thickness may be on the order of 0.4 microns, although greater or lesser thicknesses may be employed. A conductive extraction grid 38 is formed on the dielectric layer 34. The extraction grid 38 may be, for example, a thin layer of polycrystalline silicon. An opening 40 is created in the extraction grid 38 having a radius that is also approximately the separation of the extraction grid 38 from the tip of the emitter 30. The radius of the opening 40 may be about 0.4 microns, although larger or smaller openings 40 may also be employed.
In operation, signals coupled to the emitter 30 allow electrons to flow to the emitter 30. Intense electrical fields between the emitter 30 and the extraction grid 38 then cause field emission of electrons from the emitter 30. A positive voltage, ranging up to as much as 5,000 volts or more but generally 2,500 volts or less, is applied to the faceplate 20 via the transparent conductive layer 24. The electrons emitted from the emitter 30 are accelerated to the faceplate 20 by this voltage and strike the cathodoluminescent layer 26. This causes light emission in selected areas known as pixels, ie., those areas adjacent to the emitters 30, and forms luminous images such as text, pictures and the like.
FIG. 2 is a simplified plan view showing rows 42 and columns 44 of the emitters 30 and the openings 40 of FIG. 1, according to the prior art. The columns 44 are divided into top columns 44a and bottom columns 44b, as may be seen in FIG. 2. Top 46a and bottom 46b column driving circuitry is coupled to the top 44a and bottom 44b columns, respectively. A row driving circuit 48 is coupled to odd rows 42a and even rows 42b. The rows 42 are formed from strips of the extraction grid 38 that are electrically isolated from each other. The columns 44a and 44b are formed from conductive strips that are electrically isolated from each other and that electrically interconnect groups of the emitters 30.
By biasing a selected one of the rows 42 to an appropriate voltage and also biasing a selected one of the columns 44 to a voltage that is about forty to eighty volts more negative than the voltage applied to the selected row 42, the emitter or emitters 30 located at an intersection of the selected row 42 and column 44 are addressed. The addressed emitter or emitters 30 then emit electrons that travel to the faceplate 20, as described above with respect to FIG. 1.
Conventional circuitry for driving emitters 30 in field emission displays 10 enables each column 44 once per row address interval and disables each column 44 once per row address interval. The columns 44 present a capacitive load C. Charging and discharging of the capacitance C consumes power in proportion to fCV2, where f represents the frequency of charging and discharging the column 44 and V represents the voltage to which the columns 44 are charged. Charging and discharging of the columns 44 in order to drive the emitters 30 forms a major component of the electrical power consumed by the display 10. As a result, reducing the frequency f, the capacitance C or the voltage V can significantly reduce the electrical power required to operate the display 10. Displays 10 requiring less electrical power are currently in demand.
There is therefore need for techniques and apparatus that reduce the amount of electrical power required in order to operate field emission displays.
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This invention relates generally to an imaging system, and more particularly, to reducing artifacts caused by detector signal lag.
In at least one known imaging system configuration, an x-ray source projects a fan-shaped beam which is collimated to lie within an X-Y plane of a Cartesian coordinate system and generally referred to as the xe2x80x9cimaging planexe2x80x9d. The x-ray beam passes through the object being imaged, such as a patient. The beam, after being attenuated by the object, impinges upon an array of radiation detectors. The intensity of the attenuated beam radiation received at the detector array is dependent upon the attenuation of the x-ray beam by the object. Each detector element of the array produces a separate electrical signal that is a measurement of the beam attenuation at the detector location.
In at least one known type of imaging system, commonly known as a computed tomography (CT) system, a group of x-ray attenuation measurements, i.e., projection data, from the detector array is referred to as a xe2x80x9cviewxe2x80x9d. A xe2x80x9cscanxe2x80x9d of the object comprises a set of views made at different projection angles, or view angles, during at least one revolution of the x-ray source and detector. In an axial scan, the projection data is processed to construct an image that corresponds to a two dimensional slice taken through the object. Typically, each slice represents less than approximately 2 cm of coverage of the patient in the patient or z-axis and is generated from data collected from 984 views during a rotation of the gantry. One method for reconstructing an image from a set of projection data is referred to in the art as the filtered back projection technique. This process converts the attenuation measurements from a scan into integers called xe2x80x9cCT numbersxe2x80x9d or xe2x80x9cHounsfield unitsxe2x80x9d, which are used to control the brightness of a corresponding pixel on a cathode ray tube display.
At least one known CT system collects data utilizing a large flat panel digital x-ray device, or detector, having a plurality of pixels arranged in rows and columns. However, such flat panels suffer from detector lag. The detector lag causes a significant portion of the signals from previous samples to incorrectly bias subsequent samples. A significant cause of the lag is related to the electron de-trapping resulting from the high density electronic defects in an energy gap. De-trapping times range from a few milliseconds to as long as 100 seconds. As a result of the non-uniformity of the lag, artifacts, such as rings and bands, occur in the reconstructed images.
It is desirable to provide an imaging system which utilizes a solid-state detector to generate substantially xe2x80x9cartifact freexe2x80x9d volumetric images. It would also be desirable to provide such a system which reduces a detector lag artifacts without significantly increasing the time required to generate the images.
These and other objects may be attained in a digital x-ray imaging system which, in one embodiment, collects projection data from a plurality of views and reduces detector residual signals between the collection of adjacent views. More specifically and in one embodiment, the imaging system includes an x-ray source and at least one solid-state x-ray detector. To generate volumetric images, at least one of the x-ray source and the x-ray detector are rotated around the object of interest. For each identified view, x-rays are emitted from the x-ray source toward the x-ray detector and projection data is collected for the view. During an inactive period between the collection of projection data for adjacent views, the emission of x-rays is stopped and each pixel of the detector is simultaneously energized at least once.
More specifically, during the inactive period, each scan line of the detector is simultaneously energized. The simultaneous energizing of all of the scan lines reduces a residual signal of each pixel. As a result, when projection data is collected for a subsequent view, the signal level of each pixel more accurately reflects the attenuation of the object of interest for the current view. Using the projection data collected for the plurality of views, cross-sectional images of the object of interest are generated.
Using the above described imaging system, detector lag artifacts are reduced to generate substantially xe2x80x9cartifact freexe2x80x9d volumetric images. In addition, the system does not significantly increase the amount of time required to generate the images.
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Conventional images are prepared from imagewise exposed photographic silver halide materials by subjecting them to one or more photographic processing solutions that include the various photochemical components necessary for providing a black-and-white and/or color image. At the very least, such materials require photochemical processing in a developer (to "develop" a silver image from exposed silver halide grains) and a fixer (to "fix" and remove unexposed silver halide). Color photographic processing requires additional steps in order to provide an acceptable dye image, for example a silver bleaching step between color development and fixing.
The various chemical formulations used in conventional photoprocessing steps have been prepared in both liquid and solid form. Many of the necessary photochemical components are already in solid form, and in early years of photography, solid processing compositions were common. However, it was often difficult to mix the solid components in a uniform fashion, and long mixing times were often then required for preparing aqueous working strength solutions. In addition, some of the photochemical components were reactive with each other, and could not be kept together without severe losses in activity, providing evidence of poor shelf life or stability.
More recently, commercial compositions have been prepared, shipped and used as aqueous solutions. Sometimes, they are provided in concentrated form in order to minimize costs associated with weight and volume, but they then require dilution upon use.
Even though concentrates provide some advantage in economy, they are usually storable for only a limited period of time, and the reduced amounts of solvent contained therein still increases shipping and storage costs. Thus, the photographic industry has long sought ways to provide stable photoprocessing formulations in dry form. Various manufacturers have developed powders, granules, solid tablets and other dry forms in recent years in response to these needs.
To date, solid compositions have not been widely accepted in the trade. One reason is that fine powdered compositions pose health risks to workers trying to formulate working solutions when the fine dust becomes airborne in the workplace. In addition, powdered chemicals are difficult to mix uniformly and consistently on a small scale, for example, in smaller photoprocessing labs. To achieve high uniformity, high energy mixing is required, and many photoprocessing customers cannot afford the needed mixing equipment or space. As the powders are made more fine, the dust problem increases and solubilization becomes more difficult.
In response to these problems, various means have been used in the industry to make powdered or granulated photochemicals, for example, fluidized bed agglomerators (see U.S. Pat. No. 4,923,786 of Kuhnert et al), extrusion processes (see U.S. Pat. No. 3,981,732 of Emoto et al), and freeze drying (U.S. Pat. No. 4,816,384 of Fruge et al).
Solid tablet chemistries have also been developed in the industry (see for example, U.S. Pat. No. 5,316,898 of Ueda et al), but the tablets lack widespread acceptance because they are more expensive than conventional photochemical compositions.
Clearly, there is a need in the art for dry, uniformly mixed photoprocessing compositions that are affordable, easy and safe to use, and readily prepared using readily available equipment and procedures. This invention is directed to solving these problems and meeting these needs.
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Power management techniques for electronic systems are becoming increasingly important. Memory devices, such as flash memory devices and DRAM devices, consume a significant portion of the overall power consumed by various electronic systems. In the prior art, most power management techniques for memory devices involved changing the frequency of one or more clocks received or used by the memory device. In general, decreasing a clock frequency generally will result in less power consumption.
However, certain portions of a memory device, such as a sense amplifier used to read data from a memory array, will consume the same level of power regardless of any changes in clock speed. This is inefficient because prior art sense amplifiers often are designed to achieve the highest performance possible at the highest possible clock speed. In instances where a lower clock frequency is used, as might be the case in a prior art power saving mode, the sense amplifier will be operating at an unnecessarily high performance level.
What is needed is an improved method and apparatus for performing power management in a memory device where the incoming clock frequency is detected and the memory device's operation and power consumption is altered based on the clock frequency.
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File storage cabinets are used for filing documents and are generally of the vertical and lateral type. Such file cabinets usually include a number of file drawers vertically stacked with each file cabinet being moveable from within the cabinet housing to an extended open position to provide access to the drawer space.
If more than one drawer is moved to the open position at the same time, the file cabinet assembly has tendency to tip forward in the opening direction of the drawers. In other words, the center of gravity of the cabinet is shifted sufficiently forward that the entire assembly becomes unstable and can dangerously fall forward.
Many mechanisms have been developed to overcome this tipping problem by preventing more than one drawer from being opened at a time. U.S. Pat. No. 4,772,028, issued Sep. 20, 1988 in the name of Steven M. Boyer, and assigned to the assignee of the subject invention, discloses a drawer interlocking means for storage cabinets. Such a storage unit includes a vertical member extending on a first side of the storage units for locking all of the storage units at a time and opening the same. Included on a second side of the storage units is a blocking member which prevents opening movement from the closed position of all but one of the storage units. A mechanical key element unlocks the locking member allowing access to the storage units and opening of one storage unit when unlocked.
It is desirable to utilize an electronic storage interlocking system rather than a single key. Electronic opening assemblies have been known in single door opening systems wherein electronics codes may be applied to allow unlatching of a door. Such systems are disclosed in U.S. Pat. No. 4,083,424 to von den Stemmen et al, and U.S. Pat. No. 3,812,403 to Gartner, and U.S. Pat. No. 3,831,408 to Featherman, and PCT application PCT/AU87/00014 in the name of Blake.
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The invention relates to semiconductor memory devices.
Non-volatile memories have been used for many different applications. In microprocessor or microcontroller-based systems, for example, non-volatile memory devices may store boot-up code to initialize the systems during power-up sequences. In other electronic devices, non-volatile memory devices may be used to store information that would otherwise be lost if power is removed.
One type of non-volatile memory is the electrically erasable and programmable read-only memory (EEPROM). In an EEPROM, a memory cell typically includes a memory transistor having a floating gate that is capacitively coupled to a select gate. A thin oxide layer is typically formed between the floating gate and the drain of the memory transistor. Under the influence of applied high voltages, a memory cell is programmed by Fowler-Nordheim tunneling of electrons through the thin oxide layer between the drain and floating gate of the memory transistor. Fowler-Nordheim tunneling, also referred to as cold-electron tunneling, is a quantum-mechanical effect that allows electrons to pass through an energy barrier at a silicon-silicon dioxide interface at lower energy levels than hot-electron tunneling.
Referring to FIGS. 10A and 10B, a double-polysilicon EEPROM cell is illustrated. Single-polysilicon and triple-polysilicon EEPROM cells have also been implemented with varying memory cells structures. A word line 10, in combination with doped regions 12 and 14 and a gate oxide layer 11, form an access transistor 20 (as illustrated in the equivalent circuit diagram of FIG. 10B) that is an enhancement-type n-channel metal silicon oxide field effect transistor (MOSFET). The doped region 12 is coupled to a bit line, which in turn is coupled to sensing circuitry that senses the state of the memory cell during a read cycle. A control gate 22 is stacked and separated by an insulating layer 24 above a floating gate 26 of a memory transistor 40. The control gate 22 and floating gate 26 are capacitively coupled by a coupling capacitor C.sub.C formed by electrodes 22, 26 and dielectric layer 24.
The floating gate 26 includes a protruding portion 28 at its bottom surface, which is separated from the doped region 14 by a thin oxide layer 30, which forms the dielectric layer of a thin oxide capacitor C.sub.T. The remaining oxide layer 32 surrounding the thin oxide layer 30 formed between the floating gate 26 and the substrate 34 provides the dielectric layer of a capacitor C.sub.BG. The combination of C.sub.T and C.sub.BG provides the gate capacitance of the transistor 40. As illustrated in FIG. 10B, the control gate 22 is coupled to the source of a transistor 50 (also an enhancement-type n-channel MOSFET) having a drain coupled to an ERASE line and a gate coupled to the word line 10.
To program the memory cell, the word line is driven to an elevated voltage Vpp, which may be around 16 volts, for example. The bit line 12 is also coupled to the elevated voltage Vpp, which drives the doped region 14 to a voltage that is Vpp less a threshold voltage (Vt) with body effect of the enhancement-type transistor 20 (e.g., less than around 14 V). The ERASE line is coupled to a ground voltage, which causes the control gate 22 to also be grounded. Due to the induced electric field between the doped region 14 and the control gate 22, electrons tunnel from the floating gate 26 through the thin oxide layer 30 to the doped region 14, leaving the floating gate relatively more positively charged. This shifts the threshold voltage of the memory transistor 40 in the negative direction so that during a read mode the transistor is in the on state or the logical "0" state.
In an erase operation of the illustrated conventional EEPROM cell, the word line 10 is also driven to Vpp while the bit line 12 is driven to ground. The ERASE line is set to Vpp, which drives the control gate 22 to a voltage that is Vpp less a threshold voltage (Vt) of the enhancement-type MOSFET 50. The low-to-high transition of the control gate 22 is capacitively coupled through the coupling capacitor Cc to the floating gate 26. The gate capacitance of the memory transistor 40, including C.sub.BG, counteracts this capacitively coupling to some degree, which may require a higher Vpp level to adequately capacitively couple the floating gate to an elevated level for erasing. Because the drain 14 of the storage transistor 40 is driven to ground through the transistor 20, the induced electric field between the floating gate 26 and doped region 14 causes electrons to tunnel to the floating gate 26 from the doped region 14. The threshold voltage of the memory transistor 40 shifts in the positive direction so that during a read the transistor is in the off or logical "1" state.
To read the device, the word line 10 is driven to a normal high voltage (Vcc) and the erase line may be driven to about 2 volts or more. The state of the memory cell is determined by sensing current through the transistor 20 and the bit line.
In conventional EEPROMs, the voltage level of Vpp used to program and erase memory cells is typically maintained at a relatively high level to overcome (1) threshold voltage drops associated with enhancement-type MOSFETs coupled to control access to bit lines and erase lines; and (2) the capacitively coupling effect of the memory transistor's gate capacitance counteracting the capacitively coupling of the control gate to the floating gate. The elevated voltage levels of around 16 volts, for example, may give rise to reliability issues in addition to increasing power consumption in such devices. Further, the memory cell structures of conventional EEPROMs may not be efficient for embedded applications due to manufacturing complexities and density requirements.
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This invention relates generally to an adhesive tape comprising a tackified natural rubber latex and a primer.
The use of natural rubber in pressure sensitive adhesives is well known. Such adhesives employ solvent-borne natural rubber, in which rubber obtained by centrifuging natural rubber latex is masticated and applied to a backing material from a solvent solution. The mastication process decreases the molecular weight of the rubber, which is believed to result in improved adhesion, possibly at the expense of cohesive strength.
There has been no significant commercial production of adhesive coatings made from water-borne rubber to date, despite the fact that environmental and health factors would favor the use of water-borne rubber. Anchorage of the adhesive to the filmic backing is a critical problem in natural rubber latex adhesive tapes. When rolls of the tape are unwound, delamination and adhesive transfer to the back side of the film remaining on the roll frequently occur. A related concern is that the tapes generate considerable noise on commercial lines when they are unwound for slitting into small rolls of adhesive tape.
Adhesive tapes from waterborne natural rubber latex have been known since the 1940""s, when methods were developed to incorporate water-insoluble solid tackifiers into aqueous dispersions. The problem of anchorage was addressed by incorporating addition polymer emulsions. Unfortunately, addition polymers are detrimental to the adhesive properties of the tape and thus are not commercially useful.
Japanese patent application, JP 11-172212 (1999), suggests that an adhesive comprising natural rubber latex, synthetic rubber latex, and an ethylene-vinyl acetate-acrylate copolymer emulsion provides good anchorage. All examples without the EVA copolymer have poor anchorage and high unwind noise due to stepped delamination. However, this reference acknowledges that use of the EVA copolymer has a detrimental effect on the adhesive properties, a deficiency which is partially overcome by the use of the synthetic rubber.
The problem addressed by this invention is to find a pressure sensitive tape adhesive containing natural rubber latex and having a good balance of adhesive properties, as well as anchorage. An additional benefit for a pressure sensitive tape would be low noise upon unwinding.
The present invention is directed to an adhesive tape comprising: (a) a polymer film; (b) a primer coat on said polymer film; and (c) an adhesive layer on the primer coat, the adhesive layer comprising: (i) a natural rubber latex; and (ii) a tackifier.
The term xe2x80x9cadhesive tapexe2x80x9d includes, for example, packaging tape, printable tape, specialty tape and protective film.
The term xe2x80x9cpolymer filmxe2x80x9d refers to any polymer in the form of a film suitable for manufacture of an adhesive tape. The preferred polymer films are those made from polyolefins, including but not limited to polypropylene, polyethylene and copolymers and combinations thereof; polyester; and polyvinyl chloride (PVC). The most preferred polymer film is oriented polypropylene film (OPP). Preferably, the polymer film has undergone corona or flame treatment to improve anchorage prior to being coated with primer and adhesive.
The term xe2x80x9cacrylic polymersxe2x80x9d refers to polymers of acrylic acid, methacrylic acid and their esters, and copolymers predominantly comprising the aforementioned monomers.
The term xe2x80x9ctackifierxe2x80x9d refers to a resin or combination of resins which imparts tack to an adhesive formulation, especially in the context of a tape adhesive. Preferred tackifiers include rosin tackifiers, polyterpene resins, aliphatic hydrocarbon resins, aromatic petroleum resins, phenol resins, styrene resins and coumarone-indene resins. A xe2x80x9crosin tackifierxe2x80x9d is a tackifier derived from a rosin, including but not limited to rosins, rosin esters, rosin derivatives, hydrogenated rosins, hydrogenated rosin esters and hydrogenated rosin derivatives. The rosin tackifier is included as the solid resin or as a liquid dispersion or emulsion. The preferred rosin tackifier is a rosin ester tackifier.
The term xe2x80x9cprimerxe2x80x9d refers to a solvent-based or aqueous material applied to a polymer film backing to form a primer coat, thereby increasing anchorage of a tape adhesive to the film. In one preferred embodiment, the primer coat comprises a natural rubber and a crosslinked polymeric phase; this primer coat typically is formed by applying to a polymer film a primer comprising: (i) a natural rubber; (ii) at least one additional polymeric component containing functional groups suitable for crosslinking; and (iii) a crosslinking agent. Preferably, at least one of the additional polymeric component(s) in the primer has a Tg no greater than xe2x88x9210xc2x0 C. In another preferred embodiment, the primer is a solvent-based or aqueous polymer composition in which the principal bulk polymeric phase has a Tg no greater than xe2x88x9210xc2x0 C. Preferably, the primer comprises an aqueous polymer composition in which at least one polymeric component has a Tg no greater than xe2x88x9210xc2x0 C., and which contains a crosslinking agent. Most preferably, the primer contains a single polymeric phase. Preferred primers include solvent-based or aqueous acrylic polymers, ethylene-vinyl acetate copolymers, ethylene-vinyl acetate-acrylic copolymers, as well as natural and synthetic rubbers such as polyisoprene, polyisobutylene, styrene-butadiene copolymers, and styrene-butadiene-acrylonitrile copolymers, and copolymers or mixtures of the aforementioned polymers. Optionally, the primer includes other additives such as plasticizers or tackifiers. In a preferred embodiment of the invention, the polymeric component of the primer comprises at least 0.2% of monomer units bearing a functional group suitable for crosslinking, e.g., carboxylic acid, hydroxyl, and amine; more preferably at least 1%. Still more preferably, the polymeric component includes an acrylic polymer having a Tg no greater than xe2x88x9210xc2x0 C. and comprising from 1% to 5% of acrylic acid or methacrylic acid monomer units, most preferably from 1.5% to 2.5%. In one preferred embodiment of the invention, the primer comprises an acrylic polymer containing at least 0.2% of monomer units having carboxylic acid functionality, a natural rubber latex, a tackifier and an isocyanate crosslinker.
Preferably, at least one crosslinking agent is added to the primer, preferably before coating the primer on the polymer film. A crosslinking agent is a material effective for crosslinking, e.g., via hydroxyl or carboxylic acid functional groups in an aqueous medium or in a solvent. Preferably, one of the crosslinking agents well known in the art is used with a primer which includes a polymeric component bearing the appropriate functional groups. These crosslinking agents include, but are not limited to, difunctional or polyfunctional isocyanates, blocked isocyanates, carbodiimides, diamines, triamines, polyamines, aziridines, amine functional resins, e.g., melamines and urea-formaldehyde resins, epoxy resins, epoxides, acids, anhydrides and polymers with conjugated unsaturation. Preferred crosslinking agents are those which are effective for crosslinking via either hydroxyl or carboxylic acid functional groups, or both, especially difunctional or polyfunctional isocyanates and carbodiimides. Preferably, the crosslinking agent is added to the primer at a level from 1% to 20% by total weight of primer, most preferably from 1% to 10% by total weight of primer.
The primer typically is coated onto the film to form a primer coat with a dry coat weight from 0.5 to 6 g/m2, preferably from 2 to 3 g/m2. The adhesive layer is applied to the primer coat. Preferably the primer coat is dried prior to application of the adhesive layer. In a preferred embodiment of the invention, the primer coat has been crosslinked by a crosslinking agent present in the primer.
Preferably, the adhesive layer contains less than 25% of a synthetic rubber. Most preferably, the adhesive layer is substantially free of synthetic rubber, e.g., polyisoprene or styrene-butadiene rubber, or other synthetic polymers.
In one embodiment of the invention, the adhesive contains from 1% to 10% of latex particles each of which has a void and a particle size from 50 to 500 nm, as described in U.S. Pat. No. 5,663,213. Such particles act as uv absorbers in the adhesive. Preferably, the adhesive contains from 3% to 6% of said latex particles.
The adhesive tape optionally contains other additives typically used in adhesive tapes, e.g., antioxidants, uv stabilizers, mechanical stabilizers, surfactants, defoamers, pigments, humectants and plasticizers.
The present invention is directed also to an adhesive tape produced by:
(a) applying a primer to a polymer film to form a primer coat; and (b) applying to the primer coat an adhesive comprising: (i) a natural rubber latex; and (ii) a tackifier. Preferably, the natural rubber latex and the tackifier are mixed to form an adhesive, which is then applied to the primer coat. Preferably, the primer coat is dried prior to application of the adhesive.
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Cell culture of mammalian cells has long been used for the production of many vaccines and genetically engineered proteins. Animal cells are generally categorized according to their anchorage-dependence. Some cell types, such as lymphocytes, can grow in suspension; others, called "anchorage-dependent", including fibroblasts and epithelial and endothelial cells, must attach to a surface and spread out in order to grow. Other cells can grow either in suspension or anchored to a surface.
Anchorage-dependent cells have historically been cultivated on the walls of roller bottles or non-agitated vessels such as tissue culture flasks, which are used in many laboratories. As the necessity has developed to provide large amounts of certain antiviral vaccines, genetically engineered proteins, and other cell-derived products, attempts have been made to develop new systems for larger scale production of cells.
The first focus of this development effort was to increase the growth surface area per unit vessel volume and to implement convenient and appropriate environmental controls. Some of these technologies involved the use of packed-glass beads, stacked plates, rotating multiple tubes, and roller bottles with spiral films inside.
Among the most important advances in the field of cell culture technology have been the use of microcarriers and more recently, the use of hollow fiber systems. Original microcarriers developed by van Wezel (van Wezel, A. L., "Growth of Cell-Strains and Primary Cells on Micro-carders in Homogeneous Culture," Nature 216:64-65 (1967)) consisted of positively charged DEAE-dextran beads suspended in culture media in a stirred vessel. Cells would attach to the bead surface and grow as a monolayer.
Hollow fiber bioreactor configurations serve to compartmentalize the bioreactors. In one common configuration, these units allow cells to grow on the outside surfaces of bundles of parallel fibers enclosed in an outer compartment. Nutrient- and gas-enriched medium flows through the fibers' hollow centers. Cell products are concentrated in the outer compartment of the bioreactor because the inner surface of the fiber includes an ultrafiltration membrane that excludes large molecular-weight cell products.
Bioreactors have certain minimum requirements: an aeration system is required to bring the correct amount of oxygen to the cells without causing shear damage; surfaces are required for supporting anchorage-dependent cells; and means are required to enable operators to sample and monitor the contents of the bioreactor without contaminating the culture.
The various bioreactors have encountered similar problems in culturing cells. With respect to anchorage-dependent cells, specific cell culture parameters in need of improvement include: (1) better initial attachment and growth of cells to decrease the concentration of cells required for inoculation of a culture; (2) improved long-term cell adhesion, viability, and productivity to increase the useful life of the bioreactor; and (3) alteration of growth conditions to allow lower concentrations of serum to be used in the culture medium.
The adhesion of cells to a surface is a multi-step process, consisting of initial attachment (characterized by weak binding and little cell shape change) followed by cell spreading (which produces stronger binding of cells to the substrate) (Grinnell, F., "Cellular Adhesiveness and Extracellular Substrata", Internat. Rev. Cytology 53:65-144 (1978)). The initial attachment can be mediated by non-specific mechanisms such as charged surfaces (Grinnell, F., "Cellular Adhesiveness and Extracellular Substrata", Internat. Rev. Cytology 53:65-144 (1978) and Microcarrier Cell Culture. Principles and Methods, Pharmacia Fine Chemicals, Uppsala, Sweden, pages 5-33 (1981)). In contrast to initial attachment, cell spreading seems to require the presence of specific receptor-ligand interactions between cell surface receptors and certain cell adhesion glycoproteins, such as fibronectin, laminin, and collagens (Kleinman, H. K., Luckenbill-Edds, F. W. Cannon, and G. C. Sephel, "Use of Extracellular Matrix Components for Cell Culture", Anal. Biochem. 166:1-13 (1987)). All three types of these glycoproteins have been purified and added to tissue culture surfaces to promote cell adhesion and cell growth (Kleinman, H. K., Luckenbill-Edds, F. W. Cannon, and G. C. Sephel, "Use of Extracellular Matrix Components for Cell Culture", Anal. Biochem. 166:1-13 (1987)). Studies have shown that a coating of gelatin or denatured collagen on microcarders facilitates the attachment and growth of mammalian cells (Microcarrier Cell Culture. Principles and Methods, Pharmacia Fine Chemicals, Uppsala, Sweden, pages 5-33 (1981)).
Early microcarriers were in the form of DEAE-derivatized dextran beads. The use of these beads, however, produced certain deleterious effects. For example, a high initial cell death rate and inadequate cell growth was observed with cells attached to beads that contain an ion-exchange capacity that was too high. Two methods that have been proposed to overcome some of these deleterious effects involved (1) attaching a lower density of positively-charged molecules to the beads, in order to provide a charge capacity of 0.1-4.5 meg/g dextran (see, e.g., U.S. Pat. No. 4,293,654), and (2) adsorbing polyanions onto the positively-charged microcarriers, in order to neutralize some of the excess charge (see, e.g., U.S. Pat. No. 4,036,693).
It has been reported that the adsorption of an attachment glycoprotein (fibronectin) from serum onto the surface of positively-charged microcarriers promotes cell spreading in non-agitated cultures (Lai, C-S, E. G. Ankel and L. E. Hopwood, "Membrane Fluidity of Chinese Hamster Ovary Cells on Plasma Fibronectin-Coated Microcarriers", Exp. Cell Res. 150:77-83 (1984); Microcarder Cell Culture. Principles and Methods, Pharmacia Fine Chemicals, Uppsala, Sweden, pages 5-33 (1981)). On the other hand, the presence of adsorbed fibronectin has been shown to have the undesirable effect of decreasing the rate of cell attachment to stirred, i.e., agitated, microcarders (Himes, V. B. and W. S. Hu, "Attachment and Growth of Mammalian Cells on Microcarders with Different Ion Exchange Capacities", Biotech. Bioeng. 29:1155-1163 (1987)).
Cell adhesion proteins (e.g., fibronectin, laminin, and collagens) used in the absence of positively-charged groups have worked well to promote the growth and spreading of cells in non-agitated cell culture devices, but do not appear to effectively attract and attach cells with a sufficient rate or tenacity in agitated devices.
The incorporation of positive charges onto macroporous gelatin microcarriers was reported to greatly improve the rate of cell attachment to these microcarriers (Kim, J-H, H-S Lim, B-K Han, M. V. Peshwa, and W. S. Hu, "Characterization of Cell Growth and Improvement of Attachment Kinetics on Macroporous Microcarriers", presented at the Fourth Annual Meeting of the Japanese Association for Animal Cell Technology, Fukuoka, Japan (November 1991)).
Most currently used microcarriers use porous non-rigid dextran as a support matrix. This compressible matrix is believed by some to reduce the potential for damage to the microcarriers and attached cells when the microcarriers collide in agitated reactors Microcarder Cell Culture. Principles and Methods, Pharmacia Fine Chemicals, Uppsala, Sweden, pages 5-33 (1981)). Such porous microcarriers, however, frequently also have the disadvantage of retaining cellular products that are secreted into the medium (thus complicating the harvesting of desired cell products) as well as the disadvantage of adsorbing growth factors and other serum components, thus reducing their levels in the culture media (Butler, M., "Growth Limitations in Microcarder Cultures", Adv. Biochem. Eng./Biotech. 4:57-84 (1987)).
Polystyrene microcarriers produce superior cell growth, with higher recovery of products; however, currently available polystyrene microcarders produce unacceptably low rates of cell attachment.
While not considered to be art against the instant application, PCT application publication No. WO 91/07485, published May 30, 1991 (now abandoned), which corresponded to U.S. Ser. No. 434,092 (assigned to the assignee of the instant application) describes, inter alia, a bioreactor cell culture surface having a cell adhesion factor and positively charged chemical moiety.
In spite of the art and other earlier efforts described above, those involved in the cell culture of anchorage-dependent cells remain desirous of a bioreactor support surface having both cell adhesion factor and positive charge provided in a manner that is stable in the course of agitation during incubation.
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N/A
This application relates generally to file backup systems and more particularly to the administration of a differential file backup system in a client-server environment.
Client-server network systems are well known and widely used in many industries and for many applications. In a typical client-server system, a user operating a client machine sends data to one or more central computers, the server, for processing. The processed data may be stored locally on the client or centrally on the server. In either case, a single point failure, i.e., the failure of the primary data storage system, whether on the client or on the server, can result in a catastrophic loss of data. To prevent this loss of data due to a single point failure, a file backup system is commonly employed to allow recovery of the client data.
Traditional file backup systems perform a full backup of a file designated to be backed and then save full backup versions of that file only when changes had been made to it. These systems require large amounts of storage space and over time, the storage requirements became untenable. Differential backup systems provided an improvement in the amount of storage required over time by not repeating a full backup of a file after the initial save of the file. In these systems only the changes, i.e., the differential between the original file and the new file, are saved. In this way, a file can be reconstructed by combining the various components of the file that include the initial file fully saved(the base) and the plurality of differential files (the delta files). This incremental approach to backup file systems can reduce the backup time, and the storage requirements for the overall system.
Differential or incremental backup file systems do have a few problems associated with their operation. First, differential backup systems are not as robust as full file backup systems. Second, a large number of old versions of a file can accumulate within the backup storage device occupying potentially valuable storage space and increasing the recovery time. Third, differential file backups received over a long period of time can result in the fragmentation of the various file components over the media, and in the case of tape backup system, the file components may be distributed across several different tapes.
It would therefore be desirable to be able to back up files in such a way that the file components are contained on a small number of tapes and that the data is processed to allow a file backup system to reclaim storage space by processing the file components.
A method for administrating a differential file backup system in a client-server environment is disclosed. In one embodiment, the method includes reducing the number of access points associated with the components of a file that has been stored on the file backup system that include a base file and at least one delta file. A server reads data from a first memory device used by the file backup system. The data includes the base file and the at least one delta file of a backup file of interest and writes the data to a second memory device. The server then processes the data contained in the second memory device to reduce the number of access points the components of the backup file have across the first memory device.
In one aspect of the invention, the files that comprise the placements of the components of the backup file of interest are reconfigured so that the component files are adjacent to one another when written to the first memory device after processing. In another aspect the component files of the backup file of interest are grouped according to the date of the last modification of the file.
In another embodiment of the present invention, a subset of the component files that include the base file and one or more delta files are coalesced together to form a new base file. In one aspect of this embodiment, the files are selected according to one or more file expiration rules. In another aspect, the subset of files are selected according to the number of delta files that exist after the last base file was created. In another aspect, the server determines the size of the files that are to be coalesced together and estimates the size of the new base file after coalescing. The coalescing operation will only be performed if the difference between the two sizes is greater than a predetermined value.
In another embodiment of the present invention the server detects if a coalesced file contains corrupted data and requesting that the appropriate client retransmit an uncorrupted copy of the file to the server.
In another embodiment, the files to be backed up are further stored in archive files that are written to the first memory device of the file backup system. The archive files are processed to reduce the number of access points relative to a backup file of interest by reading the archive files from the first memory device of the file backup system, and writing the archive files to a second memory device. The server rearranges the archive files that contain components of the backup file to be adjacent when written back to the first memory device. In another aspect, the component files within the archive files can be rearranged so that files that have not been modified recently are grouped together and files that have recently been modified are grouped together.
In another embodiment, the server selects a backup file of interest and reads the components from the first memory device of the backup system to the second memory device. The server reconstructs the backup file of interest and detects if the reconstruction of the backup file fails. In the event of the failure to reconstruct the backup file, the server requests that the client retransmit the most recent version of the file corresponding to the backup file of interest. The server receives the retransmitted file and stores that version, and deletes the corrupted file.
In another embodiment, the server selects a backup file of interest and reads the components from the first memory device of the backup system to the second memory device. The server reconstructs the backup file of interest and detects if the reconstruction of the backup file fails. In the event of the failure to reconstruct the backup file, the server requests that a mirror server transmit an uncorrupted version of the backup file of interest. The server receives the retransmitted file and stores that version, and deletes the corrupted file.
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This invention is based on Patent Application Nos. 2000-30154 Pat. and 2000-383221 Pat. filed in Japan, the contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a filtering apparatus, especially a filtering apparatus including a filtering vessel, wherein a precoat filtering layer is formed with a filter aid on a filtering bed between a nonfiltered liquid chamber, into which a nonfiltered liquid to be filtered is introduced, and a filtered liquid chamber, so that the nonfiltered liquid introduced into the nonfiltered liquid chamber is filtered while moved through the precoat filtering layer to the filtered liquid chamber to be let out of the filtered liquid chamber.
The present invention also relates to an open/close valve for the filtering apparatus.
2. Description of the Background Art
Various processing liquids, such as a plating liquid, a dying liquid, a liquid photo developer and an ordinary cleaning liquid, are widely filtered for reuse with a filtering apparatus that includes a pump and a filtering vessel.
This is because of increases in impurities, as the liquids are repeatedly used, like impurities carried in with an article which is to be processed, impurities generated due to a change in quality like deterioration of the processing liquids and/or external impurities to fall into the liquids.
Liquid refining and filtering are also widely adopted for those such as liquid industrial chemicals, liquid pharmaceuticals and drinks.
A typical example of the above filtering apparatus is a filtering apparatus including a filtering vessel, wherein a precoat filtering layer is formed with a filter aid (filtering material) on a filtering bed between a nonfiltered liquid chamber, into which a nonfiltered liquid to be filtered is introduced, and a filtered liquid chamber, so that the nonfiltered liquid introduced into the nonfiltered liquid chamber may be filtered while moved through the precoat filtering layer to the filtered liquid chamber to be let out of the filtered liquid chamber.
FIG. 3 is an example of the conventional apparatus. The filtering apparatus in FIG. 3 is provided with a filtering vessel 8. The filtering vessel 8 includes a nonfiltered liquid chamber 83 where a nonfiltered liquid L is introduced to be filtered, a filtered liquid chamber 84 and a filtering bed 81 therebetween where a precoat filtering layer 82 is formed with a filter aid (filtering material), so that the nonfiltered liquid L, introduced, while pressurized, through a nonfiltered liquid inlet port 831 at a bottom of the nonfiltered liquid chamber 83, is filtered, while moved through the precoat filtering layer 82 to the filtered liquid chamber 84, and a filtered liquid Lxe2x80x2 is let out through a filtered liquid outlet port 841 at a bottom of the filtered liquid chamber 84.
In addition to the filtering vessel 8, the filtering apparatus 8 in FIG. 3 includes the following:
1) a nonfiltered liquid introduction pipe line 1 for introducing the nonfiltered liquid L to be filtered into the nonfiltered liquid chamber 83 through the nonfiltered liquid inlet port 831 of the nonfiltered liquid chamber, which includes a pump P, a first open/close valve (openable and closable valve) V1 connected to a suction port of the pump P and a check valve V7, located between a pump discharge port of the pump P and the nonfiltered liquid inlet port 831 of the nonfiltered liquid chamber,
2) a filtered liquid outlet pipe line 2, including a second open/close valve V2, for letting out the filtered liquid Lxe2x80x2 through the filtered liquid outlet port 841 of the filtered liquid chamber 84,
3) a bypass pipe line 3 for precoating, from the filtered liquid outlet port 841 of the filtered liquid chamber 84 to the suction port of the pump P via a third open/close valve V3,
to be more detailed according to the figured example, a bypass line 3 for precoating, from a liquid flow branch point M2, located between the filtered liquid outlet port 841 of the filtering vessel 8, and the second open/close valve V2 of the filtered liquid outlet line 2, to a liquid flow confluence point M3, located between the pump suction port and the first open/close valve V1 of the nonfiltered liquid introduction line 1, via the third open/close valve V3, and
4) a filter aid introducing pipe line 5, from a prearranged precoating liquid outlet port 85 (for example, a precoating liquid outlet port arranged at the nonfiltered liquid chamber 83, or, according to the figured example, a precoating liquid outlet port prearranged on an uppermost portion of the nonfiltered liquid chamber 83) of the filtering vessel 8, to a liquid flow confluence point M1, located between the pump suction port and the first open/close valve V1 of the nonfiltered liquid introduction line 1.
The introducing line 5 is, though not limited to this, according to the figured example, a line from the precoating liquid outlet port 85 to the suction port of the pump P, via a fifth open/close valve V5, a filter aid addition part t and a sixth open/close valve V6. The filter aid (filtering material) addition part t according to the figured example is formed in a shape of a tank with an opening, for addition of the filter aid or the like, provided on an uppermost portion. A lowermost end 511 of a pipe line 51, from the precoating liquid outlet port 85 of the filtering vessel 8 to the filter aid addition part t via the fifth open/close valve V5, is inserted and opened into the tank t. A liquid outlet port at a bottom of the tank t is connected to the liquid flow confluence point M1, located just before the suction port of the pump, with a pipe 52 having the sixth open/close valve V6 therebetween.
PG in the figure is a pressure gauge to measure a pressure in the filtering vessel 8.
When the filtering apparatus is in normal liquid filtering operation, only the valves V1 and V2 are opened with all the other open/close valves closed out of a plural number of open/close valves. Under the condition, the pump P is put in operation. The nonfiltered liquid L to be filtered is sucked into the pump P through the valve V1 and is discharged from the pump P to flow into the nonfiltered liquid chamber 83 through the check valve V7. The nonfiltered liquid L in the nonfiltered liquid chamber 83 flows into the filtered liquid chamber 84 under a discharging pressure of the pump through the precoat filtering layer 82 formed beforehand with the filter aid. At this time, the nonfiltered liquid is filtered. The filtered liquid Lxe2x80x2 flows to a predetermined location (not shown) out of the filtered liquid outlet port 841 of the filtered liquid chamber 84 and through the open/close valve V2.
The liquid in the filtering vessel 8 starts to flow back to the pump P when filtering operation is ended with stoppage of the pump P or when the pump is stopped due to an electric power outage. The flow, however, is stopped by the check valve V7, so that the liquid in the filtering vessel 8 stays in the vessel.
The precoat filtering layer 82 is formed, for example, in such a manner as follows:
The open/close valve V2 of the filtered liquid outlet line 2, the open/close valve V3 of the bypass line 3 for precoating and the sixth open/close valve V6 of the line 5 are closed, when the filtering vessel 8 is free from any liquid inside as immediately after installation of the filtering apparatus, or is cleaned and free from any liquid. On the other hand, the open/close valve V1 of the nonfiltered liquid introduction line 1 and the fifth open/close valve V5 of the line 5 are opened. Under this condition, the pump P is started, when prime water W is introduced into the filter aid addition tank t and the valve V6 is opened.
The pump P, while sucking the prime water W, begins to suck the nonfiltered liquid L. The nonfiltered liquid is thus introduced into the filtering vessel 8 this way, letting out air in the filtering vessel 8 through the precoating liquid outlet port 85 and also from the pipe 51. The filtering vessel is filled with the liquid in this manner.
The liquid in the filtering vessel thus starts to flow out of the precoating liquid outlet port 85 on the uppermost portion of the filtering vessel and comes down to the tank t, which is ensured by an operating personnel to know that the filtering vessel 8 is filed with a predetermined quantity of liquid.
Prime water is kept introduced, to prevent air from being sucked to the pump, until the tank t is supplied with the liquid through the precoating liquid outlet port 85.
When the filtering vessel 8 is filled with the predetermined quantity of liquid, with the pump P still in operation, the open/close valve V3, of the bypass line 3 for precoating, is opened, the open/close valve V1, of the liquid introduction line 1, is closed and then the filter aid (filtering material) F is added into the filter aid addition tank t. Air, sucked into the filtering vessel 8 when the filter aid F is added, is purged from the valve V5 and also from the pipe 51. Upon completion of addition of the filter aid F and purging of air in the filtering vessel 8, the valves V5 and V6 are closed.
The liquid is circulated from the pump P to the nonfiltered liquid chamber 83 of the filtering vessel, the filtered liquid chamber 84, the bypass line 3 for precoating and back to the pump P. During circulation, the filter aid F is deposited on the filtering bed 81 to form the predetermined precoat filtering layer 82.
After forming the precoat filtering layer 82, normal filtering operation is possible, by opening the valve V1 of the liquid introduction line 1 and then opening the valve V2 of the liquid outlet line 2 with the valve V3 of the bypass line 3 closed.
In operation of the filtering apparatus, such problems may occur as shown below, when normal operation is started on a day after shutting down the pump on the previous day for ending a scheduled period of operation, scheduled daily operation for example.
The precoat filtering layer 82 may be damaged due to partial detachment of the filter aid from the precoat filtering layer caused by a pressure drop in the nonfiltered liquid chamber at the time of pump shutdown. Or, the precoat filtering layer 82 may be damaged due to partial detachment of the filter aid from the precoat filtering layer 82 caused by mixing or stirring, at the time of pump restarting, of air sucked from a pump axial seal portion or the like during previous filtering operation to stay in the uppermost portion of the filtering vessel 8.
For purposes including reinstatement of thus damaged precoat filtering layer, the filter aid that may, for example, be floating or have settled down in the nonfilterd liquid chamber 83 is again made to attach to or settle down on the filtering bed 81 beforehand, using the line 5 and the bypass line 3 for precoating, as described above without further addition of the filter aid or with further addition of the same on an required basis.
A conventional filtering apparatus such as the one above, however, has a problem below.
For forming the precoat filtering layer 82, the open/close valve V3, of the bypass line 3 for precoating, is opened to circulate the liquid through the filtering vessel 8, so, at an initial stage of precoat filtering layer formation, the filter aid and part of sludge in the nonfiltered liquid chamber leak from the nonfiltered liquid chamber 83 to the filtered liquid chamber 84, and come from the filtered liquid chamber 84 to a liquid inlet section of the open/close valve V2, via the liquid flow branch point M2 of the liquid outlet line 2, and stay in the liquid inlet section of the valve V2 and also in the line thereto Because of this, the filter aid, particularly a fine filter aid, sludge in the liquid and the like that have passed through the filtering bed while the filtering bed 81 is not fully precoated, stay and/or settle down in an area like the liquid inlet section of the valve and in the line thereto. Sludge and/or the filter aid among other things that have thus stayed and/or settled down come floating in the filtered liquid that should be clean, during normal operation for filtering the nonfiltered liquid after precoat filtering layer formation is completed.
A defective product, therefore, tends to be made in product processing with the filtered liquid like plating due to sludge and/or the like above attached to the processed product. Also, it is difficult to obtain a liquid refined to a desired level for liquid industrial chemicals, liquid pharmaceuticals, drinks or the like.
In addition to the above, problems below are also observed.
The filtering vessel 8 is usually installed on a pedestal located on a higher elevation than a floor of the filtering apparatus for consideration of piping and the like. The check valve V7, along the pipe between the pump P outlet port and the nonfiltered liquid inlet port 831, is in a vertical position with the liquid inlet port down and the outlet up, which makes the pedestal considerably tall giving a personnel working there risk the more.
Furthermore, when the pump P is shutdown, a partially detached filter aid and the like from the precoat filtering layer 82, coming back to the check valve, tend to cause malfunctioning of the check valve V7.
An object of the invention is to provide a filtering apparatus, including a filtering vessel, where a precoat filtering layer is formed with a filter aid (filtering material) on a filtering bed between a nonfiltered liquid chamber, into which a nonfiltered liquid to be filtered is introduced with a pump, and a filtered liquid chamber, so that the nonfiltered liquid introduced into the nonfiltered liquid chamber is filtered while moved through the precoat filtering layer to the filtered liquid chamber to be let out of the filtered liquid chamber and also including a line for precoating the filtering bed with the filter aid using the nonfiltered liquid, wherein staying of sludge, part of the filter aid and the like in the nonfiltered liquid used for precoating is suppressed in a line for letting the filtered liquid out of the filtered liquid chamber and so, the more cleanly filtered liquid is obtained during normal filtering operation after the precoat filtering layer is formed.
Another object of the invention is to provide the above filtering apparatus, wherein a pedestal is made shorter in height, if the filtering vessel is located on the pedestal, to make work on the pedestal the safer, and part of the filter aid and/or the like detached from the precoat filtering layer, at the time of pump shutdown, do not easily come back to a check valve installed along a line for introduction of the nonfiltered liquid to the nonfiltered liquid chamber of the filtering vessel, and, therefore, ill-effect on the check valve and furthermore an upstream pump axial seal portion by the detached filter aid and the like is suppressed and so proper and effective filtering operation is maintained for a long time.
Still another object of the invention is to provide an open/close (openable and closable) valve, for the filtering apparatus including the above mentioned filtering vessel and the line for precoating the filtering bed, which is to be installed along the line to let the filtered liquid out of the filtered liquid chamber and able to suppress staying of sludge, part of the filter aid and the like in the nonfiltered liquid used for precoating, in the line for letting the filtered liquid out of the filtered liquid chamber so that the more cleanly filtered liquid is obtained during normal filtering operation after the precoat filtering layer is formed.
The invention provides a filtering apparatus and an open/close (openable and closable) valve for the apparatus as described below.
(1) Filtering Apparatus
A filtering apparatus comprising:
a filtering vessel, wherein a precoat filtering layer is formed with a filter aid (filtering material) on a filtering bed between a nonfiltered liquid chamber having a nonfiltered liquid inlet port, through which a nonfiltered liquid to be filtered is introduced, and a filtered liquid chamber having a filtered liquid outlet port, so that the nonfiltered liquid introduced through said nonfiltered liquid inlet port into the nonfiltered liquid chamber is filtered while moved through said precoat filtering layer to said filtered liquid chamber to be let out of said filtered liquid chamber through the filtered liquid outlet port;
a nonfiltered liquid introduction line, including a pump and a first open/close valve connected to a suction port of said pump, for introducing the nonfiltered liquid to be filtered into said nonfiltered liquid chamber through said nonfiltered liquid inlet port;
a filtered liquid outlet line, including a second open/close valve, for letting out the filtered liquid through the filtered liquid outlet port of said filtered liquid chamber;
a filter aid introducing line that can be opened and closed, including a filter aid addition part, from a prearranged precoating liquid outlet port of said filtering vessel, to a portion between the pump suction port and the first open/close valve of said nonfiltered liquid introduction line;
a bypass line for precoating, from a portion between said filtered liquid outlet port and the second open/close valve of said filtered liquid outlet line, to a portion between the pump suction port and the first open/close valve of said nonfiltered liquid introduction line, via a third open/close valve; and
a bypass line for valve cleaning, from a liquid inlet section of the second open/close valve of said filtered liquid outlet line, to a portion between the pump suction port and the first open/close valve of said nonfiltered liquid introduction line, via a fourth open/close valve.
(2) Open/Close Valve for Filtering Apparatus
An open/close valve for a filtering apparatus including a filtering vessel, wherein a precoat filtering layer is formed with a filter aid (filtering material) on a filtering bed between a nonfiltered liquid chamber having a nonfiltered liquid inlet port, through which a nonfiltered liquid to be filtered is introduced, and a filtered liquid chamber having a filtered liquid outlet port, so that the nonfiltered liquid introduced through said nonfiltered liquid inlet port into the nonfiltered liquid chamber is filtered while moved through said precoat filtering layer to said filtered liquid chamber to be let out of said filtered liquid chamber through the filtered liquid outlet port; a nonfiltered liquid introduction line, including a pump and a first open/close valve connected to a suction port of said pump, for introducing the nonfiltered liquid to be filtered into said nonfiltered liquid chamber through said nonfiltered liquid inlet port; a filtered liquid outlet line, including a second open/close valve, for letting out the filtered liquid through the filtered liquid outlet port of said filtered liquid chamber; a filter aid introducing line that can be opened and closed including a filter aid addition part, from a prearranged precoating liquid outlet port of said filtering vessel, to a portion between the pump suction port and the first open/close valve of said nonfiltered liquid introduction line; and a bypass line for precoating, from a portion between the filtered liquid outlet port and the second open/close valve of said filtered liquid outlet line, to a portion between the pump suction port and the first open/close valve of said nonfiltered liquid introduction line, via a third open/close valve; wherein
said open/close valve for the filtering apparatus is a valve used as said second open/close valve in said filtered liquid outlet line, and has a liquid outlet port at a bottom of a liquid inlet section of the valve to let out, with the liquid, impurities in the liquid inlet section.
The open/close valve according to the invention and the open/close valve in the filtering apparatus according to the invention, e. g., the second open/close valve of the filtered liquid outlet line may be of various types, so long as opened or closed. Various types of manual valves and/or automatic valves can be employed.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
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1. Field of the Invention
The present invention relates generally to interactive systems, and more particularly to an interactive conversational apparatus which utilizes pre-recorded multi-track media to store interactive conversational content and which employs voice recognition to enable verbal communication between the user and the apparatus to provide more realistic conversational content and to facilitate use of the apparatus as an educational tool or for verbal training.
2. Description of the Prior Art
Systems that perform interactive conversation are well known in the art. These systems have used a variety of different techniques to achieve interactive conversation, although none has been successful in providing full two-way intelligent sounding verbal dialog between the device and the user or in providing verbal training to children or others in need of such training.
For example, commonly owned U.S. Pat. Nos. 3,947,972 and 4,078,316, the contents of each of which are incorporated herein by reference, disclose a conversational teaching apparatus which employs a time synchronized multi-track audio tape to store educational conversation messages. This device employs one track to relay interrogatories to a user. The tracks are then used, selectable by a manual switching mechanism, to convey responsive messages.
Commonly owned U.S. Pat. Nos. 5,313,510 and 5,340,317, the contents of each of which are incorporated herein by reference, improved upon the earlier conversational system by programming conversations on a magnetic media in a decision-tree logic which allowed complex conversations to be developed using the multi-track media. The information is stored on each track in a plurality of reproducible information segments which contain interrogatory messages and associated multiple choice responses, responsive messages, informational messages, and combinations thereof. The responsive messages contained on the tracks are related in real-time and content to particular interrogatory messages on the tracks, and correspond with multiple choice selectable responses. The apparatus could exhibit pseudo-memory and multiple simultaneous pseudo-memories; exhibit profiling and substitutability; and categorize and subcategorize users of the apparatus.
Other multiple choice child response systems are exemplified by the systems disclosed in U.S. Pat. Nos. 2,921,385; 3,020,360; 2,826,828; 3,623,238; 3,546,791; 3,273,260; 3,665,615; 3,245,157; 3,284,923; 3,538,621; 3,477,144; 3,708,891; 3,255,536; 2,777,901; 2,908,767; 3,774,316; 3,194,895; 3,484,950; 3,343,280; and 3,763,577, by way of example.
One weakness of existing systems, especially for children, is that they cannot teach how to talk to the device so that the device can recognize the speech. Also, none of these prior systems utilizes voice recognition in an interactive conversational apparatus so that the apparatus could receive and respond to voice responses to interrogatory messages, informational messages, and combinations thereof generated by the apparatus. Utilization of a voice responsive interface would permit such an apparatus to retain the long-term motivational, entertainment, and educational interests of a child, and would enable the apparatus to be used to teach a child to speak, in general, to speak in such a way as to allow the device to understand human speech at a higher rate of reliability, or to verbally respond to interrogatories or commands. Such an apparatus could also be used to teach adults or children to properly interact with voice responsive systems, greatly increasing the system's user friendliness and usefulness.
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Programmable integrated circuits (ICs) are often used to implement digital logic operations according to user configurable input. Example programmable ICs include complex programmable logic devices (CPLDs) and field programmable gate arrays (FPGAs). CPLDs often include several function blocks that are based on a programmable logic array (PLA) architecture with sum-of-products logic. A configurable interconnect matrix transmits signals between the function blocks.
One type of FPGA includes an array of programmable tiles. The programmable tiles comprise various types of logic blocks, which can include, for example, input/output blocks (IOBs), configurable logic blocks (CLBs), dedicated random access memory blocks (BRAM), multipliers, digital signal processing blocks (DSPs), processors, clock managers, delay lock loops (DLLs), bus or network interfaces such as Peripheral Component Interconnect Express (PCIe) and Ethernet and so forth. Each programmable tile typically includes both programmable interconnect and programmable logic. The programmable interconnect typically includes a large number of interconnect lines of varying lengths interconnected by programmable interconnect points (PIPs). The programmable logic implements the logic of a user design using programmable elements that can include, for example, function generators, registers, arithmetic logic, and so forth.
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1. Field of the Invention
2. Description of the Related Art
The power generated by an internal combustion engine depends on the air mass and the fuel quantity which can be made available to the engine for combustion. In order to increase the power of an internal combustion engine, the quantity of combustion air and fuel supplied must be increased. In the case of a naturally aspirated engine, this power increase is achieved by an increase in swept volume or by increasing the engine speed. However, an increase in swept volume leads in principle to heavier engines of larger dimensions, which are therefore more expensive. The increase in engine speed entails considerable problems and disadvantages, especially in the case of relatively large internal combustion engines, and is limited for technical reasons.
A much-used technical solution for increasing the power of an internal combustion engine is boosting. This refers to precompression of the combustion air by an exhaust gas turbocharger or by means of a compressor mechanically driven by the engine. An exhaust gas turbocharger consists essentially of a flow compressor and a turbine which are connected by a common turboshaft and rotate at the same speed. The turbine converts the normally uselessly discharged energy of the exhaust gas into rotational energy and drives the compressor. The compressor aspirates fresh air and conveys the precompressed air to the individual cylinders of the engine. An increased quantity of fuel can be supplied to the larger air quantity in the cylinders, whereby the engine delivers more power. In addition, the combustion process is influenced favorably, so that the engine achieves better overall efficiency. Furthermore, the torque curve of an internal combustion engine boosted with a turbocharger can be configured extremely favorably. Existing naturally aspirated engines in series production by manufacturers can be significantly optimized by the use of an exhaust gas turbocharger without major interventions in engine design. Boosted internal combustion engines generally have a lower specific fuel consumption and lower pollutant emissions. Moreover, turbocharged engines are quieter than naturally aspirated engines of the same power because the exhaust gas turbocharger itself acts like an additional silencer.
For internal combustion engines with a wide operating speed range, for example, passenger car engines, a high boost pressure is required even at low engine speeds. For this purpose a boost pressure control valve, a so-called waste gate valve, is introduced with these turbochargers. Through the selection of a suitable turbine casing a high boost pressure is rapidly built up even at low engine speeds. The boost pressure control valve (waste gate valve) then limits the boost pressure to a constant value as engine speed rises. Alternatively, turbochargers with variable turbine geometry (VTG) are used. In these turbochargers the boost pressure is regulated by changing the turbine geometry.
With increased exhaust gas quantity, the maximum permissible speed of the combination of turbine wheel, compressor wheel and turboshaft, also referred to as the rotor of the turbocharger, may be exceeded. Impermissible exceeding of the speed of the rotor would destroy the latter, which is equivalent to total loss of the turbocharger. In particular modern, small turbochargers with significantly smaller turbine wheel and compressor wheel diameters, which have improved rotational acceleration behavior through a considerably lower mass moment of inertia, are affected by the problem of exceeding the permissible maximum rotational speed. Depending on the design of the turbocharger, exceeding of the rotational speed limit even by approximately 5% causes complete destruction of the turbocharger.
Boost pressure control valves which, according to the prior art, are activated by a signal resulting from the boost pressure generated, have proved effective for limiting rotational speed. If the boost pressure exceeds a predetermined threshold value, the boost pressure control valve opens and conducts a part of the exhaust gas mass flow past the turbine. Because of the reduced exhaust gas mass flow, the turbine absorbs less power and the compressor output is reduced proportionally. The boost pressure and the rotational speed of the turbine wheel and the compressor wheel are reduced. However, this regulation is relatively sluggish, because the pressure build-up in the event of the rotor exceeding a given speed occurs with a time offset. For this reason, regulation of turbocharger speed by monitoring boost pressure, especially in the high dynamic range (load change), must intervene by correspondingly early reduction of boost pressure, incurring a loss of efficiency.
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1. Field of the Invention
This invention relates to an improved recording system in which signals obtained from an information source can be stably recorded in different portions on a recording medium, and more particularly to a recording system in which a plurality of picture information obtained from image pick-up devices such as a CCD or the like can be stably recorded during a short period of time.
2. Background of the Invention
For example, when one field of video signals is recorded in one track on a recording medium such as a magnetic sheet, it is conventionally known that a gate is provided in a signal path connecting a video signal source with a recording head, and the gate is opened intermittently during, for example, only one field interval per several fields to record the video signals in each track, and that while the gate is closed, the recording head is shifted to face the next track.
However, it is extremely difficult to shift the recording head within the limited period of vertical blanking time, causing a drawback in that the video signals recorded would have been forced to be intermittent.
Therefore, when one tries to compose a picture using the signal of one field twice, the picture must have been blurred or unfocussed if the subject is a moving object, and a satisfactory picture quality will not be obtained if the signal of one field is used once.
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It is well known that particulates of metals or metal oxides with sizes at nanometer level or submicron level are very useful industrial products in many fields of application. These applications include the manufacture of catalysts used in chemical industry, pottery and porcelain, electronic elements, coating, capacitor, mechanical-chemical polishing slurry, magnetic tape and fillers for plastics, paint or cosmetics.
It is possible to produce ultra fine particulates of metals or metal oxides by many different technologies including high temperature gas phase method, mechanical method, chemical method and etc. Reviews on the general technology of the production of nanometer grade particulate were published in the following papers: V. Hlavacek and J. A. Puszynski, “Advances in the Chemical Industry of Advanced Ceramics”, Industrial Engineering and Chemistry Research, 1996, vol. 35, 349–377; “Advances on the Method of Preparation for Nanometer Particulates”, Chemistry Bulletin (in Chinese), 1996, No. 3, 1–4. In CN 1217387A, there was also a detailed discussion on the advantages and disadvantages of the different technologies.
The process of the liquid phase precipitation method is simple. When compared with the gas phase method, solid phase method or other liquid phase method, its controlling condition is not so critical and its cost is lower. Therefore nowadays the liquid phase precipitation method becomes one of the widely used methods.
The characteristics of the process of the common liquid phase precipitation method are as follows: Stirring pot is used to carry out mixing reaction. At least one of the reactant solutions is gradually added into the pot by dropping, flowing in or spraying for a relatively long time. Using this technology to prepare nanometer particulates although has the advantage of simple operation, low cost and high yield, however the method has three generally recognized disadvantages: (1) It is difficult to control particle diameter; (2) It is difficult to obtain very small particle diameter; (3) It is difficult to eliminate hard agglomeration among particulates. The origin of the drawbacks of the pot technology comes from too long feeding time for one of the reactant solution and from the stirring together of the reaction, product and precipitate formed at different stage of time. Nuclei formed at the initial stage will undergo growth and collision coalescence among small particulates to form nanometer particulates. Due to long time, nanometer particulates will grow to relatively larger in size and will agglomerate together among nanometer particulates. The participation of the product formed in the later stages will induce agglomeration hardening. As mentioned above, these are the causes of the above-mentioned three drawbacks of the large pot technology in preparing nanometer powder.
Therefore, people successively developed different kinds of process of liquid phase precipitation method for producing nanometer powder without the use of stirring pot. Patent Appl. SE 99/01881 disclosed the following method and facilities: On the basis of a stream of carrier fluid flowing continuously in a pipe, two kinds of reactant solutions were injected in the form of periodical, intermittent pulse into the pipe at the same location. The reaction zone where the mixing of the injected two reactant solutions took place was separated in the carrier fluid. The lasting time for the course of mixing, reacting, and forming precipitate was very short. The said invention claimed that the quality of the nanometer particulates was very good, with particulate size at 10–20 nm, slight inter-particulate agglomeration or even no agglomeration. The drawbacks of that method are: (1) Reactant solutions are injected in pulse mode and the mixing process is not continuous. Thus the process is not favorable for large-scale continuous industrial production. Since carrier fluid must be used, the manufacturing process gets complex. It not only consumes carrier fluid but also needs to add a process of separation treatment for the carrier fluid and etc and thus increases the production cost. (2) The said method does not take any effective measures to reinforce and to adjust the mechanical mixing efficiencies of the two reactant solutions. Therefore it is not possible to effectively control the mechanical mixing efficiency of the reactant solutions. The above two drawbacks both shall be improved.
Other 2 papers, “Preparation of Strontium Carbonate Nanometer Powder by Liquid-Liquid Method in Rotating Packed Bed”, Science and Technology in Chemical Industry (in Chinese), 1999, 7(4) 11–14 and “Experimental Study on Microscopic Mixing in Rotating Packed Bed”, Chemical Reaction Engineering and Technology (in Chinese), 1999, 9, Vol. 15, No. 3, 328–332, described another kind of continuous process without the use of stirring pot. Two reactant solutions were allowed to pass continuously through rotating packed bed at one time. In the rotating packed bed, two reactant solutions mixed, reacted, formed nuclei and formed nanometer particulates. The paper stated that under the action of super gravity, the reactant solutions passed through the rotating packed bed and were dispersed, broken by the packing and formed very large and continuously refreshing surface area, greatly reinforced the material transfer condition. Besides, the process of rotating packed bed has the advantage of high intensity of fluid passage and short resident time. However, there were still some drawbacks in the method of super gravity rotating packed bed. Due to the high compactness of the fillers such as steel wire net and in the packed bed, what obtained by the solution was not the action of stirring and shear. When solution entered into the packed bed, it as a whole rotated with the packed bed and obtained centrifugal force. Under the action of centrifugal force, the solution would flow from inner fringe of the rotor to outer fringe along the interstitials of the packing and in the course of this process, mixing of solution took place. The mechanical mixing intensity and the adjusting sensitivity of such kind of mixing were not high enough and thus the performance of the preparation of nanometer powder was not ideal. Except for nanometer powder of CaCO3 and SrCO3, no report on the successful preparation of important species such as ZrO2, TiO2 by using rotating packed bed was disclosed. Therefore the said method seems to need further improvements.
As mentioned above, a good mixing and reacting facility for continuous passage of two reactant solutions should have the characteristics of high mechanical mixing intensity, adjustable mechanical mixing intensity and simplicity of structure. Within such facility, the solution should acquire vigorous stirring, shear and turbulence and would quickly be separated, broken into isolated very small sized micro liquid agglomerates in order to enlarge the interface of the two solutions thus to provide good conditions for the processes of molecular diffusion, chemical reaction, nucleation and etc.
Therefore, the objective of the present invention is to provide a method of preparing nanometer powder by liquid phase precipitation. The method of the present invention adopts a mixing facility which is simple in structure, could provide high and adjustable mechanical mixing intensity and could be used for large-scale production of good quality nanometer powder. The said method is widely applicable in the production of nanometer powders of oxides, hydroxides, salts, metals and etc.
After consulting the following text, readers would have a better understanding on the objective, advantages and features of the present invention.
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The present invention is generally directed to sensors and, more specifically, to sensors adapted to determine the depth of liquid in a drum.
It may be advantageous to provide a sensor that is preferably: simple to manufacture, relatively inexpensive to manufacture, relatively reliable, relatively easy to install, capable of determining the depth of liquid in a drum, capable of determining the volume of liquid in a drum, capable of knowing when liquid is being withdrawn from the drum instead of a non withdrawal event, capable of monitoring withdrawals over time and detecting trends or deviations from the norm so that gradual malfunctions or changes in use can be detected, and/or capable of sending alerts if the volume of liquid withdrawn from the drum is less than a predetermined volume.
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One issue with data track mining of large databases of geo-referenced trajectories is that algorithms that cluster data tracks may require time-consuming and inefficient user interaction. For example, user interaction may be required to determine how many clusters there are within the track data, and user interaction may be required to select a preferred or “best” cluster from the clusters. Further, clustering algorithms may apply metrics that do not satisfy requirements, or axioms, of a metric space. Therefore, artifacts may appear when conventional clustering algorithms are used.
Thus, there are general needs for algorithms to determine a number of clusters in track data with little or no user input. There are also general needs to determine these clusters based on a metric space that satisfies axioms of a metric space so that artifacts may be reduced or eliminated.
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Technical Field
The present invention relates to multigate devices, and, more particularly, to sidewall image transfer methods and structures employed in the fabrication of multigate devices.
Description of the Related Art
Fin density control and, in particular, fin density quadrupling can be implemented by performing a plurality of sidewall image transfer etching steps to form fins of multigate devices. However, these processes typically employ a relatively complicated patterning stack. For example, one such stack is composed of at least ten different layers and is relatively costly to fabricate and to utilize in fin formation processes.
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Various types of exercise devices are known in the prior art. However, what is needed is a resistance exercise device to exercise the arms and upper core of the body. The device includes a pair of handle assemblies connected together with a replaceable elastomeric resistance member to permit the use of a resistance member having a desired length and resistance strength. Each handle assembly includes a handle member and a convex support member attached thereto which are separable to permit replacement of a non-slip hollow cylindrical hand grip that engages a center portion of the handle member.
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Meats, poultry, and other food items have typically been smoked in smokehouse-type systems. Smokehouse systems commonly involve batch-type operations wherein food items are placed in cages, or on racks, which are then placed in a smoking chamber. In the smoking chamber, smoke circulates down the sides and then up through the center of the chamber. The smoking process typically involves (1) a heat-up cycle wherein moisture is removed from the surfaces of the food items in order to prepare the items for smoking, followed by (2) a smoking cycle.
Smokehouse operations have many shortcomings. For example, batch-type smoking operations for poultry items commonly require five to seven hours or more. In addition to being inefficient, these slow smoking processes can sometimes impart an extremely dark color and/or an overpowering smoke flavor to the food items. Smokehouses commonly also do not provide desirably uniform temperature and smoke profiles. The existence of hot spots and low smoke points within the smoking chamber can cause substantial variations in the nature and quality of the products produced.
Some smokehouse operations have been modified to include means for pushing the smoking racks/cages through the smoking chamber or through a series of chambers wherein different phases of the smoking process are conducted. U.S. Pat. No. 4,976,009 discloses a smokehouse assembly including a sequence of processing chambers and a trolley assembly for carrying meat racks through the chambers. Each chamber includes an internal diffuser panel which is intended to provide improved air distribution within the chamber. A heat exchanger assembly is mounted in each chamber above a fan. The fan moves air downwardly from the heat exchanger, through the diffuser panel, and then over the meat items hanging on the rack.
Unfortunately, the use of a trolley-type system to push product racks or cages through sequential smoking chambers or zones does not resolve the problems mentioned above. Such smoking processes are still slow, still require a relatively high level of product handling, and are therefore costly and inefficient. Additionally, due to the length and nature of the smoking process, the products produced therefrom tend to be very dark in color and can have an overpowering smoke flavor. Further, non-uniform temperature and smoke profiles within the chambers can result in substantial variations in the nature and quality of the products produced.
Continuous fired ovens and continuous indirectly heated ovens are known in the art. To our knowledge, no one has heretofore used such continuous ovens for simultaneously cooking and smoking food items.
An indirect heated, continuous impingement oven 2 of a type known in the art is depicted in FIG. 1. The oven comprises: a housing 4 including a base portion 6 and a liftable hood 8; a belt-type conveyor 10 for continuously conveying food items through the oven; a circulation system 12 for circulating a cooking medium (preferably air) through the oven; at least one burner 14 or other heating device for indirectly heating the cooking medium; and impingement headers 15 positioned above and below conveyor 10. Impingement headers 15 include a plurality of impingement nozzles, impingement orifices, and/or other such impingement structures 16. As will be understood by those skilled in the art, impingement devices 16 are operable for applying the cooking medium to the food items in an impinging manner.
Circulation system 12 will typically include at least one fan or other type of blower 17 which draws (recirculates) the cooking medium 13 from oven chamber 18 into blower inlet 19 and then delivers the cooking medium through impingement structures 16. Circulation system 12 will also typically include a heating element and/or heating chamber wherein burner 14 indirectly heats the cooking medium to a desired cooking temperature. Because the cooking medium is indirectly heated by burner 14, the combustion product produced by burner 14 (i.e., flames and combustion gases) does not contact either the cooking medium or the food products.
If allowed to contact food items such as poultry, combustion gases can act as curing agents and impart a raw, pink color to the meat. The end user of the product could therefore mistakenly believe that the product is not thoroughly cooked. For this and other reasons, indirect- fired ovens are generally preferred over direct-fired ovens for at least certain types of cooking operations.
Impingement structures 16 are positioned above, below, and across the width of conveyor 10 to thereby completely envelope the food items in a high velocity cooking atmosphere. Thus, each food item is properly cooked, regardless of its position on conveyor 10. Such uniformity minimizes overcooking and provides optimal yields. Conveyor 10 preferably utilizes a low density (highly porous) belt to ensure good air contact on the bottoms of the food items.
Continuous impingement oven 2 will also typically include: a steam system for humidifying the cooking atmosphere; systems for selecting and controlling temperatures, humidities and air velocities; means for adjusting nozzle height and conveyor height; a hoist for lifting oven hood 8; and a sealing system (e.g., a water seal) for sealing the sides of oven 2 when hood 8 is lowered onto base 6.
It is also typical that oven 2 be divided into a plurality of cooking zones and/or that a plurality of ovens 2 be operably linked together. When linked together in series, the ovens 2 will commonly employ a single conveyor 10 which extends through all of the ovens. A different set of cooking parameters can be employed in each individual zone and/or oven. In multizone systems, it is typical that a relatively high heat input be used in the first zone in order to bring the product up to cooking temperature. Less heat is needed in subsequent zones since the product need only be maintained at cooking temperature.
An indirect heated continuous spiral oven 22 of a type known in the art is depicted in FIG. 2. Spiral oven 22 comprises: an oven housing 24 having a cooking chamber 25; a spiral, belt-type conveyor system 26 for conveying food items through oven chamber 25; a circulation system 28 for circulating a cooking medium (preferably air) through chamber 25; and at least one burner or other heating device 30. Circulation system 28 includes at least one fan or other type of blower 31 and has a blower inlet 32. As with the heating device 14 used in impingement oven 2, heating device 30 is preferably operable for indirectly heating the cooking medium so that none of the heating medium/combustion product produced by device 30 contacts either the cooking medium or the food items.
Circulation system 28 and heating device 30 operate in substantially the same manner as the circulation system 12 and heating device 14 of impingement oven 2 except that the spiral oven circulation system 28 typically does not include an impingement system. Rather, circulation system 28 delivers the heated cooking medium into cooking chamber 25 such that the cooking medium passively contacts and heats the food items conveyed on spiral conveyor 26. Spiral conveyor 26 will typically employ a dense belt (i.e., a belt which is either nonporous or has a low porosity) such that, when circulating system 28 delivers the hot cooking medium to the top of spiral conveyor 26, the cooking medium generally flows in a passive manner down the spiral belt (i.e., generally parallel to the belt) to the bottom of the oven.
Because spiral oven 22 employs a passive contacting system rather than an impingement system, the required cooking time in spiral oven 22 will typically be greater than the cooking time required in impingement oven 2. For poultry products, the cooking time in a continuous spiral oven 22 will typically be in the range of from about 40 minutes to about 1 hour as compared to a cooking time in a continuous impingement oven 2 in the range of from about 10 to about 25 minutes.
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The present invention relates to methods and system structures for providing public and private telephone service over the Internet and more particularly relates to providing such services through the public telecommunications system including over existing copper telephone lines.
Attention recently has been directed to implementing voice telephone service over the worldwide network now commonly known as the Internet. The Internet had its genesis in U.S. Government (called ARPA) funded research which made possible national internetworked communication systems. This work resulted in the development of network standards as well as a set of conventions for interconnecting networks and routing information. These protocols are commonly referred to as TCP/IP. The protocols generally referred to as TCP/IP were originally developed for use only through Arpanet and have subsequently become widely used in the industry. TCP/IP is flexible and robust, in effect, TCP takes care of the integrity and IP moves the data. Internet provides two broad types of services: connectionless packet delivery service and reliable stream transport service. The Internet basically comprises several large computer networks joined together over high-speed data links ranging from ISDN to T1, T3, FDDI, SONET, SMDS, OT1, etc. The most prominent of these national nets are MILNET (Military Network), NSFNET (National Science Foundation NETwork), and CREN (Corporation for Research and Educational Networking). In 1995, the Government Accounting Office (GAO) reported that the Internet linked 59,000 networks, 2.2 million computers and 15 million users in 92 countries. It is presently estimated that the growth of the Internet is at a more or less annual doubling rate.
Referring to FIG. 1 there is shown a simplified diagram of the Internet. Generally speaking the Internet consists of Autonomous Systems (AS) which may be owned and operated by Internet Service Providers (ISPs) such as PSI, UUNET, MCI, SPRINT, etc. Three such AS/ISPs are shown in FIG. 1 at 10, 12 and 14. The Autonomous Systems (ASs) are linked by Inter-AS Connections 11, 13 and 15. Information Providers (IPs) 16 and 18, such as America Online (AOL) and Compuserve, are connected to the Internet via high speed lines 20 and 22, such as T1/T3 and the like. Information Providers generally do not have their own Internet based Autonomous Systems but have or use Dial-Up Networks such as SprintNet (X.25), DATAPAC and TYMNET.
By way of current illustration MCI is both an ISP and an IP, Sprint is an ISP, and MicroSoft (MSN) is an IP using UUNET as an ISP. Other information providers, such as universities, are indicated in exemplary fashion at 24 and are connected to the AS/ISPs via the same type connections here illustrated as T1 lines 26. Corporate Local Area Networks (LANs), such as those illustrated in 28 and 30, are connected through routers 32 and 34 and links shown as T1 lines 36 and 38. Laptop computers 40 and 42 are representative of computers connected to the Internet via the public switched telephone network (PSTN) are shown connected to the AS/ISPs via dial up links 44 and 46.
The Information Providers (IPs) constitute the end systems which collect and market the information through their own servers. Access providers are companies such as UUNET, PSI, MCI and SPRINT which transport the information. Such companies market the usage of their networks.
In simplified fashion the Internet may be viewed as a series of routers connected together with computers connected to the routers. In the addressing scheme of the Internet an address comprises four numbers separated by dots. An example would be 164.109.211.237. Each machine on the Internet has a unique number which constitutes one of these four numbers. In the address the leftmost number is the highest number. By analogy this would correspond to the ZIP code in a mailing address. At times the first two numbers constitute this portion of the address indicating a network or a locale. That network is connected to the last router in the transport path. In differentiating between two computers in the same destination network only the last number field changes. In such an example the next number field 211 identifies the destination router. When the packet bearing the destination address leaves the source router it examines the first two numbers in a matrix table to determine how many hops are the minimum to get to the destination. It then sends the packet to the next router as determined from that table and the procedure is repeated. Each router has a database table that finds the information automatically. This continues until the packet arrives at the destination computer. The separate packets that constitute a message may not travel the same path depending on traffic load. However they all reach the same destination and are assembled in their original order in a connectionless fashion. This is in contrast to connection oriented modes such as frame relay and ATM or voice.
One or more companies have recently developed software for use on personal computers to permit two-way transfer of real-time voice information via an Internet data link between two personal computers. In one of the directions, the sending computer converts voice signals from analog to digital format. The software facilitates data compression down to a rate compatible with modem communication via a POTS telephone line. The software also facilitates encapsulation of the digitized and compressed voice data into the TCP/IP protocol, with appropriate addressing to permit communication via the Internet. At the receiving end, the computer and software reverse the process to recover the analog voice information for presentation to the other party. Such programs permit telephone-like communication between Internet users registered with Internet Phone Servers.
The book xe2x80x9cMastering the Internetxe2x80x9d, Glee Cady and Pat McGregor, SYBEX Inc., Alameda, Calif., 1994, ISBNT 94-69309, very briefly describes three proprietary programs said to provide real-time video and voice communications via the Internet.
Palmer et al. U.S. Pat. No. 5,375,068, issued Dec. 20, 1994 for Video Teleconferencing for Networked Workstations discloses a video teleconferencing system for networked workstations. A master process executing on a local processor formats and transmits digital packetized voice and video data, over a digital network using TCP/IP protocol, to remote terminals.
Lewen et al. U.S. Pat. No. 5,341,374, issued Aug. 23, 1994 for Communication Network Integrating Voice Data and Video with Distributed Call Processing, discloses a local area network with distributed call processing for voice, data and video. Real-time voice packets are transmitted over the network, for example to and from a PBX or central office.
Hemmady et al. U.S. Pat. No. 4,958,341, issued Sep. 18, 1990 for Integrated Packetized Voice and Data Switching System, discloses an integrated packetized voice and data switching system for a metropolitan area network (MAN). Voice signals are converted into packets and transmitted on the network. Tung et al. U.S. Pat. No. 5,434,913, issued Jul. 18, 1995, and U.S. Pat. No. 5,490,247, issued Feb. 6, 1996, for Video Subsystem for Computer Based Conferencing System, disclose an audio subsystem for computer-based conferencing. The system involves local audio compression and transmission of information over an ISDN network.
Hemmady et al. U.S. Pat. No. 4,872,160, issued Oct. 3, 1989, for Integrated Packetized Voice and Data Switching System, discloses an integrated packetized voice and data switching system for metropolitan area networks.
Sampat et al. U.S. Pat. No. 5,493,568, issued Feb. 20, 1996, for Media Dependent Module Interface for Computer Based Conferencing System, discloses a media dependent module interface for computer based conferencing system. An interface connects the upper-level data link manager with the communications driver.
Koltzbach et al. U.S. Pat. No. 5,410,754, issued Apr. 25, 1995, for Bi-Directional Wire Line to Local Area Network Interface and Method, discloses a bi-directional wire-line to local area network interface. The system incorporates means for packet switching and for using the internet protocol (IP).
It is an object of the present invention to provide telephone service via the Internet to users of the public telecommunications network either with or without access to a computer and with or without separate telephone user access to the Internet.
It is another object of the invention to provide the general public with an economical and convenient telephone service via the Internet without requiring the possession of computing equipment or familiarity with the Internet or its methodology on the part of the user.
It is yet another object of the invention to provide the public with impulse access to the Internet for voice communications without requiring maintenance of a subscription to an Internet access service.
It is another object of the invention to provide the foregoing types of telephone service over the Internet via the public telephone network without the necessity of reliance on signaling systems of interexchange carriers.
It is yet another object of the invention to provide voice service over public telephone systems via the Internet where the use of the Internet is optional to the Telco and transparent to the customer.
It is another object of the invention to provide voice service over public telephone systems via the Internet from telephone to telephone, from telephone to computer, from computer to telephone, and from computer to computer.
It is still another object of the invention to provide the foregoing type services with billing capabilities based substantially on equipment and methodologies presently available in the public switched telephone network.
The invention constitutes a system and method for providing telephone type services over the internetwork commonly known as the Internet. Public switched telephone networks utilizing program controlled switching systems are arranged in an architecture with the Internet to provide a methodology for facilitating telephone use of the Internet by customers on an impromptu basis. Provision is made to permit a caller to set-up and carry out a telephone call over the Internet from telephone station to telephone station without access to computer equipment, without the necessity of maintaining a subscription to any Internet service, and without the requiring Internet literacy or knowledge. Calls may be made on an inter or intra LATA, region or state, nationwide or worldwide basis. Billing may be implemented on a per call, timed, time and distance or other basis. Usage may be made of common channel interoffice signaling to set up the call and establish the necessary Internet connections and addressing. Calls may be made from telephone station to telephone station, from telephone station to computer or computer to telephone station.
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Elastomers, also known as rubber materials, have found application in a diverse range of areas including tyres, shoe soles, condoms, surgical and examination gloves, catheter balloons, mining equipment and shock adsorption for bridges just to name a few. In the majority of cases, successful adoption of elastomers in these and other applications has required some modification of the base elastomer to improve their mechanical properties, including the use of particulate or fibrous materials introduced into the elastomer matrix to act as reinforcing agents. Silica in particulate form is in widespread use to reinforce elastomers, typically providing increased strength, stiffness and toughness to a base elastomer. Newer materials being investigated as reinforcing agents for elastomers include carbon nanotubes, graphene and nanoclay particles.
In the last few decades, the use of natural fibres to reinforce polymer composites has been increasing because of their sustainability, renewability, biodegradability, low thermal expansion, manufacturer-friendly attributes such as low density and abrasiveness, excellent mechanical properties such as very high specific stiffness and strength and consumer-friendly attributes such as lower price and higher performance. A typical natural fibre consists of several or more nanocrystalline elementary fibrils formed by cellulose chains (homopolymers of glucose), concreted by/in a matrix containing lignin, hemicellulose and other components. The nanofibrils consist of monocrystalline cellulose domains linked by amorphous domains. Amorphous regions act as structural defects and can be removed under acid hydrolysis, leaving cellulose rod-like nanocrystals, which are also called whiskers, and have a morphology and crystallinity similar to the original cellulose fibres. Depending on the source of cellulose, the cellulose content varies from 35 to 100%. These fibers exhibit extraordinarily higher mechanical properties (stiffness/strength) at nanoscale phases than at the microscale or in their natural state. In recent years, these nanocrystalline cellulose fibres have been explored as biologically renewable nanomaterials that can be applied in several engineering applications.
While numerous methods have been explored for the production of microfibrillated cellulose (MFC), which by definition (Reference: Robert J. Moon, Ashlie Martini, John Nairn, John Simonsen and Jeff Youngblood, ‘Cellulose nanomaterials review: structure, properties and nanocomposites’ Chem. Soc. Rev., 2011, 40, 3941-3994), consists of cellulose fibres with diameters in the range of 20-100 nm and a length range of between 0.5 and tens of μm, the production of nanofibrillated cellulose (NFC; also known as cellulose nanofibres CNFs)), and cellulose nanocrystals (CNCs), is more challenging due to the requirement to separate or deconstruct the cellulose fibres to a much greater degree. Attempts to date to produce these two types of nanocellulose (CNCs and NFCs), have focussed on the use of chemical, physical, mechanical and enzymatic pretreatments alone or in combinations thereof. For NFC, the prior art refers to a fibre diameter in the range of 3-20 nm and a length in the range between 0.5 and 2 μm. For CNC, the prior art refers to fibre diameters in the range of 3-20 nm and length up to 500 nm (except the special example of tunicate CNCs or t-CNCs, which have a higher aspect ratio).
Although both CNCs and NFCs are nanocellulose materials, they exhibit different morphologies. CNCs are typically highly crystalline rod shaped particles with typical dimensions ranging from 5 to 20 nm in diameter and from 100 to 500 nm in length. On the other hand, NFCs have a diameter typically in the range of 5 to 20 nm and lengths within the micron scale. NFCs might be considered to be bundles of elementary cellulose fibrils (also known as primary cellulose fibrils or primary cellulose nanofibrils) embedded in a (primarily) hemicellulose matrix.
Nanocellulose materials have been the subject of a number of research studies in which the nanocellulose was used in the production of a composite material. For example, Abraham et al, Physicomechanical properties of nanocomposites based on cellulose nanofibre and natural rubber latex, Cellulose, (2013), 20:417-427, published 22 Nov. 2012, describes the use of NFCs having a diameter of 10 to 60 nm and obtained by the steam explosion of banana fibre as a reinforcing material mixed with natural rubber latex. This paper described loadings of NFCs added to the latex as including 2.5%, 5%, 7.5% and 10%. Table 2 of this paper shows that adding the NFCs to the natural rubber latex resulted in significant increases in elastic modulus (stiffness), and tensile strength and a decrease in elongation (strain) at break across all loadings of NFC.
Boufi et al, “Mechanical performance and transparency of nanocellulose reinforced polymer nanocomposites, Macromol. Mater. Eng. 2014, 299, pp 560-568, describes the use of two different types of NFC (one having 20 to 50 nm diameter, 200 to 1000 nm length, the other having 10 to 20 nm diameter, 200 to 1000 nm length) and two different types of CNC (one having 15 to 25 nm diameter, 150 to 250 nm length and the other having 15 to 25 nm diameter, 150-350 nm length) being dispersed in an acrylic latex at up to 15% loading. The nanocellulose materials were extracted from two different cellulosic sources, namely alfa and date palm trees. This paper found that a huge enhancement in modulus (stiffness) was observed in the polymer composite above the glass transition temperature (rubber state). Further, this paper states that the stiffness of the composites increases with an increase in the aspect ratio of the CNC.
Chaker et al, “Reinforcing potential of nanocellulose from non-woody plants,” Polymer Composites—2013, describes the use of a number of NFCs derived from different sources (abaca, sisal, hemp, jute and flax) as fillers in an acrylic elastomer (a commercially available latex obtained by the copolymerisation of styrene (35% by weight) and butyl acrylate (65% by weight)). The NFCs had diameters in the range of 10 to 50 nm. The NFCs were described as comprising a bundle of primary nanofibrils of 3 to 5 nm diameter. The NFCs had a hemicellulose content that ranged from 6 to 20% weight. NFC loadings in the elastomer/NFC composite were up to 15% by weight. This paper observed a huge enhancement in modulus above the glass transition temperature of the elastomer. The paper states that this is a common effect seen in elastomer composites reinforced with nanocellulose. This paper also described composites including fibres with higher hemicellulose content as showing higher stiffness and tensile strengths compared to lower hemicellulose materials. FIG. 5 of this paper showed significantly increased stiffness and reduction in elongation to break on increasing NFC loadings.
US 2012/0232192 A1 discloses rubber composites incorporating organic fibres for improving the performance of automotive tyres. This document teaches the use of modified celluloses such as carboxymethyl cellulose (CMC) as an additive rather than unmodified celluloses, explaining that the presence of hydroxyl groups on unmodified cellulose promotes aggregation of the cellulose in water due to strong hydrogen bonding, resulting in poor dispersion in the rubber. The document goes on to describe modified cellulose particles that have an average diameter in the range 20 microns to 100 microns, teaching that particles with a diameter lower than 20 microns have poor dispersibility.
US 2013/0197132 A1 describes the incorporation of microfibrils of cellulose into elastomers including rubber latex. Cellulose microfibrils with diameters as low as 20 nm are disclosed in the examples however the document teaches against the use of unmodified cellulose as a reinforcing agent in rubber composites due to the poor compatibility of unmodified cellulose fibres with the rubber component. Specifically, poor adhesion at the rubber-cellulose interface is thought to contribute to increased friction and energy losses at the interface. The authors propose the addition of lignin to the cellulose fibres to modify the rubber-cellulose interface to increase adhesion at the interface.
Although increases in tensile strength and toughness are useful in a very large number of applications, in some uses, concomitant increases in elastic modulus or stiffness may not be so desirable. Reinforcing agents that have been previously used in elastomers to improve mechanical properties such as silica, carbon black, carbon nanotubes and graphene can provide an increase in tensile strength of an elastomer however due to their rigid nature, the incorporation of these materials also tends to increase the hardness and stiffness of a material and reduces the elongation to break. In many elastomer applications, increased stiffness and reduced elongation to break are detrimental to product performance such that the use of these reinforcers involves a fine balancing act and compromise between different performance features. For example, in the manufacture of condoms, it is desirable to use an elastomeric material that has good tensile strength and toughness but low elastic modulus (or high compliance). This combination of properties will result in a condom that is resistant to breakage but also allows for a close fit and improved feel or sensation. The use of elastomeric materials having undesirably highly elastic modulus is generally avoided in condom manufacture because those materials tend to decrease feel or sensitivity, and therefore cause consumer resistance.
Previous research studies focussed on using reinforcing agents to improve the mechanical properties of elastomers manufactured from latex-based systems such as natural rubber lattices and polyisoprene lattices have largely used the casting method to fabricate the elastomer composite products. Here, the reinforcing agent is added to the latex, followed by casting the mixture onto a surface and subsequently the carrier solvent is removed, leaving a composite of the elastomer and the reinforcing agent. However, commercial products such as condoms, gloves and catheter balloons that are made using latex-based elastomers are often not made by casting, but are instead made by dipping a shaped form or mould into latex followed by removal of the mould from the latex and then drying of the latex film deposited on the mould to yield a latex film or membrane of the desired shape. In such cases, the reinforcing agent that is present in the latex must not only provide improvements in the mechanical properties of the final product following dipping, but in order that the latex-reinforcing agent formulation is suitable for manufacture, the addition of the reinforcing agent must not destabilise the latex colloid so as to cause precipitation of the latex. Thus, in order to provide a manufacturable latex formulation that results in a suitably reinforced dipped product, the reinforcing agent must be well dispersed into the latex but not cause significant destabilisation. It is generally known that the extent of colloid destabilisation is approximately proportional to the amount of reinforcing agent added to the latex. Therefore, only very effective reinforcing agents will be successful in this application, that is, those reinforcing agents that can provide adequate mechanical reinforcement in the manufactured device but in quantities small enough so as not to destabilise the latex.
In other elastomer applications such as wear liners, seals and tyres similar technical requirements exist. In wear liners for example, elastomeric materials that exhibit high toughness and abrasion resistance are desired while still retaining the soft, elastic nature of the underlying rubber material. In tyres, softer compounds provide good road grip however these tend to wear more rapidly that harder compounds. Increasing the hardness of a tyre rubber compound reduces wear but at the expense of road grip. There is needed therefore, a soft rubber compound that provides good road grip while possessing good resistance to wear.
It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.
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This invention relates to hand tools, and in particular the invention is concerned with a compact hand tool for projecting plumb and level reference beams of visible light for precise alignment.
A system for generating reference beams based on first generating a plumb beam of light is the invention described herein. Many self-leveling plumb laser beam generators have used ball bearings, wires, and springs. There are also many instruments which have used electronic sensors and motors to level the projector as required. A low cost automatic self-leveling laser instrument is described in U.S. Pat. Nos. 5,459,932, 5,524,352, 5,541,727, and 5,619,802 assigned to the same assignee as the present invention. The instruments of those patents are similar in application to the present invention. The disclosure of those patents is incorporated herein by reference.
In Swierski, U.S. Pat. No. 5,184,406, the instrument of which is shown in FIG. 1, a battery operated laser projector 1 is mounted in a float 2 which floats in a partially closed pan 8 of water 6. Although this does produce a plumb beam of light, there are many disadvantages to this system. The lack of liquid containment makes it difficult to transport and set up. The accuracy can be adversely affected by mishandling of the float or the battery insertion.
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Up to now, it appeared not to be possible to remove disturbing decomposition products from electrolytic baths and from waste water produced generally by the galvanic industry, particularly by the hot dip galvanizing industry, by the hardening industry and by numerous other industries without an interruption of the production.
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1. Technical Field
The invention relates to the art of landscape materials and methods for making such materials More particularly, the invention relates to a method for making a landscape material, such as mulch, in a thinner and generally more uniform form than prior art mulch, which produces desirable characteristics in the resulting landscape material.
2. Background Art
In the landscape industry, natural fibrous material, such as mulch, is often placed around buildings, bushes, trees, stones, and other items. The mulch is typically made by grinding wood down to relatively small fibers. The wood that is used to make the mulch may be obtained from several different sources, including newly-cut trees, lumber, and scrap wood, such as old shipping pallets More particularly, in the prior art, generally large pieces of wood are placed in the feed hopper of a wood chipper or grinder, or on a conveyor leading into the grinder. The feed hopper or conveyor leads to the cutting chamber of the grinder, which includes multiple rotating heavy-duty teeth. Each large piece of wood is fed into the cutting chamber of the grinder from the feed hopper or conveyor, and the rotating teeth shred and cut the wood until it is reduced to small chunks, or mulch fibers.
Typically, a screen is placed over the exit area of the grinder, which keeps the wood in the cutting chamber of the grinder until it is reduced to a size that will pass through the openings in the screen. Depending on the size and configuration of the openings in the screen, the mulch fibers that are produced may be relatively large and coarse, or relatively small and fine. For example, each opening in a screen that is configured for coarse grinding is relatively large, such as from about 1.5 to about 2.5 inches in diameter, while each opening in a screen that is configured for fine grinding is relatively small, such as about 0.25 inches in diameter. Thus, coarse mulch may be up to about 0.5 inches in diameter, and is normally up to about 3.0 to about 4.0 inches long, while fine mulch may be up to about 0.25 inches in diameter, and is normally up to about 2.0 to 3.0 inches long. However, it is important to note that the random shredding and tearing of the wood by the teeth in the grinder results in fibers that are not uniform. That is, the resulting mulch fibers may have a maximum diameter as determined by the size of the openings in the exit screen, but the fibers are often below that maximum diameter due to the splintering of the wood as it is shredded and torn by the grinder teeth. As a result, both coarse mulch fibers and fine mulch fibers of the prior art typically randomly range in diameter and length. It is to be noted that reference herein to diameter for a cross-sectional measurement of mulch fibers is for the purpose of convenience, as such cross-sections include shapes other than those that are round, such as rectangular, square, random, etc., and all such cross-sectional shapes are included herein.
Coarse mulch and fine mulch, and particularly the fine mulch, are well-known in the art and typically are placed around bushes, plants, trees, and other items. A finer size range for mulch is desirable around bushes, plants and trees, as the mulch retains soil moisture, thereby encouraging growth of the bush, plant or tree, and inhibits weed growth. Specifically, a more fine-sized mulch enables easier placement of the mulch around bushes, plants and trees, which in turn provides increased coverage of the soil to retain more soil moisture, and to provide increased inhibition of weed growth. The finer-sized mulch is also softer to the touch than more coarse fibers, and is thereby more desirable to certain users. In addition, the finer mulch fibers often have a more desirable appearance than mulch with more coarse fibers. It should also be noted that finer mulch fibers that are more uniform in size are often more desirable to users, since the uniform fibers are often easier for a user to handle, and have a mole desirable appearance than fibers which vary greatly in size
To continue to increase the favorable properties of fine mulch fibers, it is desirable to reduce the cross-sectional area of the prior-art fine fiber size even more, and to create a more uniformly sized mulch fiber, while retaining enough fiber size to allow the mulch to be easily handled and resist premature decomposition. More particularly, if the prior-art fiber size is altered in a disadvantageous manner, the cross-sectional area and/or length of the mulch fibers may become too small, creating fibers that are difficult for a user to handle, may decompose prematurely, and/or may blow away If the cross-sectional area and/or length of the mulch fibers becomes too large, fibers would be created that are difficult for a user to spread and/or may be visually unappealing. Grinding machines of the prior art, due to their use of multiple rotating teeth to chip away at wood, typically produce such undesirable mulch fibers if they are used to attempt to reduce the size of the mulch beyond the typical prior-art non-uniform fine fiber size.
As a result, a need exists to decrease the cross sectional area of prior-art mulch fibers and to create mulch fibers that are more uniformly sized, in order to increase the desirable characteristics of the mulch, such as increased placement ability, increased softness, and a desirable appearance, without undesirably creating a mulch that is difficult to handle, or decomposes prematurely. The present invention satisfies this need by providing a landscape material with such decreased cross-sectional area and increased generally uniform size, and a method for making that material.
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Cylinders of an engine may be deactivated to reduce engine pumping work and to increase thermal efficiency in cylinders that remain active. A first group of engine cylinders may remain active and combusting air and fuel while a second group of engine cylinders are deactivated by holding intake and exhaust valves closed during an entire cycle of the engine. The first group of engine cylinders is always the same group of cylinders.
More recently, engines have been implemented with deactivating valve operators such that all of an engine's cylinders may be selectively activated and deactivated. This allows the active cylinders that combust air and fuel to periodically deactivate and deactivated cylinders to activate. The combination of active and deactivated cylinders provides the desired engine torque. Further, to provide the desired engine torque, an actual total number of active cylinders may remain the same while the active cylinders that form the actual total number of active cylinders may change from engine cycle to engine cycle. This may be referred to as a rolling variable displacement engine. Such engines provide flexibility to activate different engine cylinders, but the ability to activate and deactivate every engine cylinder adds cost to the engine system, and the cost may be prohibitive for engines with a greater number of cylinders (e.g., six and eight cylinder engines).
The inventors herein have recognized the above-mentioned disadvantages and have developed vehicle systems, comprising: a first vehicle including a first cylinder block and a first cylinder head casting, a first actual total number of deactivating valve operators coupled to the first cylinder head casting; and a second vehicle including a second cylinder block and a second cylinder head casting, a second actual total number of deactivating valve operators coupled to the second cylinder head casting, the first cylinder block same as the second cylinder block, the first cylinder head casting same as the second cylinder head casting.
By configuring different vehicles with the same engine block and cylinder heads and different actual total numbers of deactivating valve operators, it may be possible to reduce vehicle system costs for different vehicles. In particular, a larger higher mass vehicle may be configured with fewer deactivating valve operators than a lower mass vehicle that includes a same engine block and cylinder head as the higher mass vehicle. A smaller actual total number of deactivating valve operators in the higher mass vehicle increases the actual total number of non-deactivating valve operators in the higher mass vehicle so that the higher mass vehicle always has a greater total number of cylinders that cannot be deactivated when the higher mass vehicle's engine is operating as compared to the actual total number of cylinders that cannot be deactivated in the lower mass vehicle. Configuring the actual total number of deactivating valve operators based on vehicle mass or performance objectives may be desirable since the higher mass vehicle uses a greater number of active cylinders to propel the vehicle even at light driver demand conditions. In this way, a same engine block and cylinder head may be configured to reduce system cost and improve engine fuel efficiency.
The present description may provide several advantages. For example, the approach may reduce vehicle system cost. Further, the approach may provide the benefits of cylinder deactivation such as lower engine pumping work. Further still, the approach may improve reliability of cylinder deactivation since fewer deactivating valve operators may be applied based on vehicle configuration and objectives.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.
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Mechanical keys in modern portable devices can serve various purposes, such as a keyboard, for volume control, screen lock and others. Usually in devices with touch screens the mechanical keys serve a secondary purpose and are positioned on the edges of the device. The side keys are usually coupled to the printed circuit board (PCB) in order to perform their functions. The mechanical keys provide a tactile feedback different from a touch surface, so in some cases they can be preferable—cases like when a user cannot see the display of the device but wishes to give quick commands, for example change volume while the mobile phone is in the pocket.
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There appears to be an ever-increasing demand for higher levels of integration in semiconductor circuits. In order to increase the density of devices within the semiconductor structures, some of the devices have been emplaced within the depths of the substrate, in addition to being formed on its planar upper surface.
Dynamic random access memories, or "DRAM's", typically employ openings or "trenches" for memory cell capacitance. The trenches are also used to isolate individual devices within a monolithic circuit. In order to further increase the densities of these circuits, technologists have begun to form semiconductor structures within the trenches themselves, i.e., on top of or within an interior ("concave") surface of the trench. (This area of technology is thus sometimes referred to as three-dimensional or "3D" semiconductor processing.) The formation of semiconductor structures on these interior surfaces has been very difficult, since standard photolithographic techniques are not always well-suited in this situation.
A method for enhancing photolithographic capabilities for producing images on the sidewalls of trenches is described in U.S. Pat. No. 4,838,991, issued to Cote et al. A technique described in that patent involves the formation of sidewall spacers, which are very useful structural features. As an example, spacers may serve as masks for a variety of devices which can be formed in the sidewalls, e.g., field effect transistors (FETs). Spacers can also serve to control the lateral migration of an implanted dopant under the gate of an FET. The formation of spacers within a silicon body is also taught by Pogge in U.S. Pat. No. 4,256,514. Furthermore, U.S. Pat. No. 5,096,849, issued to Beilstein, Jr. et al., describes a method for selectively masking portions of the sidewall of a trench or other concave structure by forming spacers or "bands" on the sidewalls.
It's thus apparent that spacers can play an important part in the formation of devices within the surfaces of a trench or opening in a semiconductor substrate. However, there are some serious limitations to current spacer technology. For example, the final spacer film has had to be conformal, i.e., conforming to the underlying surface. The conformal materials currently used for spacers are usually oxides or nitrides which are applied by various chemical vapor deposition (CVD) techniques. Most of the conformal materials are inorganic, although an organic material, poly-p-xylylene or "parylene", is also a conformal material. The inorganic conformal materials can be difficult to etch, thus increasing processing time and complexity.
The use of non-conformal materials as spacers does not appear to be known in the art. Unfortunately, this excludes a wide variety of organic materials from consideration as spacers, e.g., organic polymers like polyimides and photoresist resins. Organic, non-conformal materials would appear to have several notable advantages over the inorganic, conformal materials currently used for spacers. For example, the organic materials could be very easily applied and patterned, using standard photolithographic techniques, such as shadow projection masks. Furthermore, organic, non-conformal spacers could be selectively removed from the inner surfaces of a trench much more easily than inorganic materials.
Reference to the Beilstein patent mentioned above is helpful in pointing to some of the difficulties involved in the formation of inorganic, conformal spacers. Beilstein describes a method for selectively masking sidewall regions of a trench formed in a semiconductor body. A conformal layer of masking material is first formed on the trench surfaces, followed by the deposition of a selectively removable material (e.g., a photoresist material) to fill the trench. Reactive ion etching of the trench-filling material to a predetermined depth d1 determines where the bottom edge of the sidewall spacer will be placed. A conformal layer of an organic material such as parylene is then deposited to cover all of the vertical and horizontal surfaces. Another reactive ion etch then removes the horizontal portions of the conformal coating, leaving sidewall portions of the coating which adhere to the sidewalls of the trench. Then, an additional layer of a photoresist-type material is deposited on the exposed surfaces of the substrate and trench. This additional layer of material and the conformal coatings previously applied are etched by RIE to a second depth d2, which will determine the top edge of the spacer. Both of the photoresist-type materials which remain can then be removed, leaving the conformal coating regions on the sidewalls, over the initial film which had been applied. A selective etch procedure can then be used to remove uncovered areas of the first coating, but not the conformal, masking layer. After removal of the masking layer, the underlying regions of the first coating are left as sidewall spacers, as depicted in the figures of the patent.
While the Beilstein technique is effective for the creation of sidewall spacers under some circumstances, it is a rather complicated process involving many steps. Furthermore, the process sometimes cannot create a spacer of very precise dimensions. For example, the depth "d1" mentioned above determines the lower boundary of the spacer. However, the reactive ion etching step used to etch the photoresist-type material to this depth may result in a depth variance of as much as + or -20%. This variation from trench-to-trench can hinder the reproduction of exact images on the sidewalls of trenches.
New methods for forming and using sidewall spacers would thus represent a welcome advance in the art of preparing high density semiconductor structures. Moreover, new materials for use as spacers would also be very desirable in the art, so that processing is not excessively dependent on the use of conformal, inorganic materials which sometimes exhibit the disadvantages discussed above. Finally, applications for employing the spacers of the present invention would also be of great interest in the formation of various semiconductor structures.
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The HQOS technology achieves multi-user multi-service bandwidth guarantees under the Differentiated Service (Diff-Serv) model through hierarchical scheduling. The structure of a HQOS service tree, as shown in FIG. 1, comprises a port layer, a user group layer, a user layer, a service layer of a total of four layers. The HQOS service tree can embody a tree-liked topology structure and service forwarding paths of a subnet accessing a network through application ports, after being bound with the application ports, and messages of the subnet can be hierarchically scheduled through the HQOS service tree, achieving functions such as congestion avoidance, multi-level scheduling, traffic rate-limiting and traffic statistics, and guaranteeing the bandwidth for each user and each service in an actual network.
At present, three HQOS services i.e., binding, de-binding and updating are used to bind the HQOS service tree and the application ports, revoke the binding between the HQOS service tree and the application ports, or update the HQOS service tree according to the variations of the network structure or associated parameters of the subnet, wherein, the updating HQOS service specifically comprises: a sub-tree adding service, a sub-tree deleting service, a master parameter updating service and a slave parameter updating service, and the device to specifically implement the above HQOS services comprises:
a service management module, which is used to receive service types and service processing information, invoke the service resource management module corresponding to the received service types, and send the received service processing information to the invoked service resource management module, wherein, the service resource management module comprises: a binding module, a de-binding module, a sub-tree adding module, a sub-tree deleting module, a master parameter updating module, and a slave parameter updating module; wherein,
the binding module is used to invoke a service tree generating function to generate the HQOS service tree; invoke a table management function to write a software table according to the received service processing information; invoke a tree traversing function to traverse the generated HQOS service tree, and record the next traversed position each time one branch is traversed, and invoke a buffer processing function and a hardware management function to apply and assign resources for each node of the traversed branch, invoke the table management function to write a configuration table according to the received service processing information, then invoke the traversing function again to continue to traverse the generated HQOS service tree from the recorded traversed position;
the de-binding module is used to determine an object service tree according to application ports and application directions in the received service processing information; invoke the table management function to delete table items corresponding to the object service tree; invoke the tree traversing function to traverse the object service tree, and record the next traversed position each time one branch is traversed, invoke the hardware management function and the buffer processing function to release the resources of each node of the traversed branch, invoke the table management function to delete the configuration table corresponding to the traversed branch, then invoke the traversing function again to continue to traverse the object service tree from the recorded traversed position;
the sub-tree adding module is used to determine the object service tree according to the application ports and the application directions in the received service processing information; determine a sub-tree to be added according to relative offsets between the layer where the nodes are located and the nodes in the received service processing information; invoke the tree traversing function to traverse the sub-tree to be added, and record the next traversed position each time one branch is traversed, invoke the buffer processing function and the hardware management function to apply and assign resources for each node of the traversed branch, invoke the table management function to write the configuration table according to the received service processing information, then invoke the traversing function again to continue to traverse the sub-tree to be added from the recorded traversed position;
the sub-tree deleting module is used to determine the object service tree according to the application ports and the application directions in the received service processing information; determine the sub-tree to be deleted according to relative offsets between the layer where the nodes are located and the nodes in the received service processing information; invoke the tree traversing function to traverse the sub-tree to be deleted, and record the next traversed position each time one branch is traversed, invoke the hardware management function and the buffer processing function to release the resources of each node of the traversed tree, invoke the table management function to delete the configuration table corresponding to the traversed branch, then invoke the traversing function again to continue to traverse the sub-tree to be deleted from the recorded traversed position;
the master parameter updating module is used to determine the object service tree according to the application ports and the application directions in the received service processing information; determine the nodes of which the QOS master parameters need to be updated according to relative offsets between the layer where the nodes are located and the nodes in the received service processing information, invoke the table management function to delete table items including the QOS master parameters on the determined nodes in the configuration table, substitute the QOS master parameters in the received service processing information for the corresponding QOS master parameters on the determined nodes, and write the paths passing through the determined nodes into the configuration table, i.e., writing the QOS master parameter of each node on the paths into the configuration table;
the slave parameter updating module is used to determine the object service tree according to the application ports and the application directions in the received service processing information; determine the nodes of which the QOS slave parameters need to be updated according to relative offsets between the layer where the nodes are located and the nodes in the received service processing information, invoke the buffer processing function to acquire the QOS slave parameters of the nodes from the received service processing information, substitute the acquired QOS slave parameters for the corresponding QOS slave parameters buffered in the determined nodes, and invoke the hardware management function to update the hardware resources of the nodes according to the QOS slave parameters after the substitution.
It can be seen that the above device for enabling HQOS services has the following drawbacks:
each HQOS service is implemented by a corresponding independent service resource management module, but a part of the implementation processes of various HQOS services are similar, which makes a part of functions of different service resource management modules be similar, for example, all of the binding module, de-binding module, sub-tree adding module and sub-tree deleting module need to invoke the tree traversing function many times and maintain the traversed position, both the binding module and the sub-tree adding module need to perform the operations for applying and assigning resources for nodes, both the de-binding module and the sub-tree deleting module need to perform the operations for releasing the resources for nodes, and so on, thus making a large number of repeated codes be within the software codes for implementing each service resource management module respectively, increasing the complexity of the codes and the difficulty in maintaining the codes, and therefore, the efficiency of processing the HQOS services is low.
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Conventionally, controlling UAVs remotely requires a user to manually navigate the UAV using controls such as joysticks or directional pads. Alternatively, a user may select a waypoint from a map and command the UAV to navigate to the selected waypoint location. Since these controls may be somewhat specialized, they may be unfamiliar to most people and therefore may require a learning curve.
The present embodiments may overcome these and/or other deficiencies.
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In the composite industry, several types of designs and shapes are used as cores, sandwiched between layers of reinforcing materials (also referred to as the outer skin) and surrounded by various resins to produce a strong, lightweight composite structure. Honeycomb core sandwich panels have been used as high performance structural elements in advanced composite industries such as aerospace, marine and automotive. Honeycomb cores and sandwich panels for industrial and military applications have been typically made of thermoplastic, aluminum, Nomex and machined honeycomb. Metal/plastic honeycomb panels with custom bonding and custom finishes are available to the present industry. The prior art honeycomb type structures have cells that are contiguous, connected and/or interlocked. The cells are not separated and do not have a space between them. This type of design does not allow for the flow of resin or other bonding material between the cells nor does it allow for a resin bond between the upper and lower skins or layers of reinforcing materials.
The most common materials used for cores are wood (plywood), end grain balsa, plastic and several types of foams designed to accept differential stresses and loads. These materials are handicapped by: (1) delamination from localized impacts; (2) delamination and rot from water and moisture intrusion around fasteners and through cracks in damaged skins; (3) expensive and time consuming manufacturing processes; (4) low strength due to delamination of the outer skin layers of reinforcing materials; (5) manufacturing processes that require vertical channels to allow for resin flow from one layer of the laminate to the other; and (6) environmentally dangerous vapor emissions caused by the application of the resins to the outer skin of reinforcing materials.
Some of the above problems with the present state of the art is a result of the manufacturing and assembly process. Typically, the reinforcing material is placed on each side of the core and resin is then spread over one or both sides of the reinforcing material. There is no direct resin bond between the top and bottom layers or skins of reinforcing material or between core cell members leading to delamination problems and reduced strength. The resin is usually applied by hand in an open environment leading to the escape of environmentally hazardous vapors.
The present core invention is designed to simplify the manufacturing process, to provide for reduced delamination failures and to provide for a stronger, lighter and more versatile composite structure. The manufacturing process can be performed in a closed production mold allowing for simpler and less expensive manufacturing. The closed molding process also prevents the escape of hazardous vapors into the environment.
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The present invention relates to a new and distinct cultivar of Heuchera hybrid and given the cultivar name of ‘Fire Chief’. Heuchera is in the family Saxifragaceae. Heuchera ‘Fire Chief’ originated from a planned breeding cross between Heuchera 834-7, a proprietary unreleased plant, as the seed parent, and Heuchera 766-4, a proprietary unreleased plant, as the pollen parent. Compared to the seed parent the new cultivar has darker foliage and a light rather than a heavy veil. Compared to the pollen parent the new cultivar has a lighter veil and red rather than purple black leaves. Compared to Heuchera ‘Peach Flambé’ (U.S. Plant Pat. No. 17,195), the new cultivar has red purple foliage tones rather than peach amber. There are no comparable foliage color Heuchera on the market.
This new Heuchera is distinguished by: 1. red to deep burgundy medium sized leaves, 2. bicolor red purple and light pink flowers on short flowering stems, 3. a compact habit, 4. excellent vigor, 5. and excellent tolerance to heat and humidity.
This new cultivar has been reproduced only by asexual propagation (division and tissue culture). Each of the progeny exhibits identical characteristics to the original plant. Asexual propagation by division and tissue culture using standard micropropagation techniques with terminal and lateral shoots, as done in Canby, Oreg., shows that the foregoing characteristics and distinctions come true to form and are established and transmitted through succeeding propagations. The present invention has not been evaluated under all possible environmental conditions. The phenotype may change with variations in environment without a change in the genotype of the plant.
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Prior art pipe coupling systems have been used for coupling a plurality of individual couplings, as shown in British Patent Specification No. 1,368,039. These systems are advantageous in that two locking plates, one with a plurality of male coupling members and the other with a plurality of complementary female coupling members, can be pulled together and locked even while being subjected to very large forces. Still these coupling systems are deficient because when the locking plates are subjected to large forces, the forces are transmitted to the individual male and female couplings and cause separation, damage and/or leakage of the coupling members.
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1. Field of Invention
This invention relates generally to a charging apparatus for an electric vehicle, and more particularly to an automated charging system for docking and charging an electric vehicle.
2. Description of Related Art
With concerns over pollution rising, there has been greater interest in the use of electric powered vehicles for passenger transportation. While limitations such as charging capacity and vehicle speed had previously made large scale implementation of electric vehicles unworkable, advances in technologies such as storage cell design, braking regeneration, and motor efficiency have made electric vehicles a viable alternative to vehicles powered by internal combustion engines. However, one major limitation to the full scale implementation of electric vehicle fleets remains: providing a safe, effective means for recharging the storage devices of electric vehicles.
For example, the power storage capacity of an electric vehicle has been improved to the point where electric vehicles now have ranges similar to that of combustion engine powered vehicles. However, while the fuel cell of a combustion engine (i.e. gas tank) can be refueled at locations like service stations in ten minutes or less, "refueling" an electric storage cell may take several hours. Therefore, it is more likely that consumers will perform the bulk of their recharging needs overnight while the vehicle is parked in their garage or during the work day while the vehicle is parked in the parking lot at work.
To date, most electric vehicle charging systems involve the connection of a power cable between the vehicle and a charging tower or station. This presents several disadvantages. First, the power cord must be provided either at the charging station or be carried with the vehicle. If the cord is provided at the power station, there is risk that the cord may become damaged due to improper use by the many different people who would utilize the charging station. The cord may become frayed, or the plug connectors damaged due to misuse or abuse. Likewise, if the cord is to be carried with the vehicle, repeated use and abuse of the cable can cause damage. Also, the driver may forget the cable, or it could be stolen from the vehicle. Whether the power cable is associated with the vehicle or the charging station, severe damage to the cable and charging connectors on the vehicle and charging station could result if the vehicle is driven away with the cord still engaged. Likewise, the power cable connecters may be damaged by accidentally driving a vehicle wheel over the power cable connector.
Also, by requiring the vehicle driver to establish the power cable connection between the vehicle and the charging station, risk of personal injury is increased. A careless or inexperienced user may accidentally short across the power terminals. Inclement weather such as rain and snow increase the risk that the charging circuit may be accidentally shorted while connecting the system. Also, there is the risk that the user may connect the polarity of the charging system incorrectly, or that the user will fail to observe proper safety procedures such as waiting until the connection is fully established before activating the power generation system.
Other contingencies pose challenges as well. For example, different types of vehicles will likely require different charging voltages and will have different charge storage capacities. Therefore, the user may be confronted with having to select the proper type of charging station and charging cord to meet his vehicle's charging requirements. Or, the user may be required to manually set the charging station to deliver the proper total charge and charging rate to his vehicle. Obviously, the chances that an inexperienced or careless user would deliver improper charging rates to his vehicle's charging system increases the likelihood that the system will be damaged and therefore require repair.
Finally, because most known methods of connecting a charging system to an electric storage cell necessitates some form of connector having a relatively higher degree of resistance than found in the other portions of the charging circuit, the charging connector becomes hot, risking injury to the user and increasing the risk that surrounding combustible materials may ignite.
It would therefore be advantageous to provide an electric vehicle charging system which does not require the user to manually establish a connection between the vehicle and the charging station. Such a system should be capable of automatically ensuring that the correct charging rate and total charge is delivered to the vehicle to prevent overcharging of the vehicle's storage system. The charging system should also be capable of ensuring a good connection is made between the charging station and the electric vehicle to ensure the vehicle is indeed being charged. Furthermore, the system should prevent the delivery of charging power from the charging station until this connection is established, to reduce the risk of injury due to shock and risk of damage to the charging circuitry. Finally, it would be beneficial if such a system were universal, such that any variety of vehicles could be charged from a single charging station, obviating the need for special adapters.
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An ultrasonic probe is used to examine items such as manufactured parts by transmitting ultrasonic signals to the item and measuring a reflected signal returned by the item to the probe. Conventional probes typically include a transducer having a single crystal that creates the outgoing ultrasonic signals and measures the signals returned to the transducer. To facilitate the transmission of signals between conventional probes and the item being examined, the item is often wetted with water where the probe will be moved. Without such a coupling fluid, some of the signals leaving the transducer would not reach the item, instead being reflected back to the transducer by a gap of air that may exist between the probe and the item.
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Due to the development of electronic technology, various kinds of electronic devices have been developed and distributed.
In particular, smartphones or tablet personal computers (PCs) which can be carried by users have become widely used in recent years. The typical smartphone or tablet PC is provided with a touch screen, and the user can control the functions of the electronic device using the touch screen.
The user can touch the touch screen using an input device of a pen type as well as a user's body (for example, a finger, etc.) The electronic device may perform various control operations according to touch coordinates of a point on the touch screen which is touched by the user's body or input device, and a menu or an icon displayed on the touch coordinates.
The input devices may be classified by their implementing methods, such as a capacitive coupling method, an electro magnetic resonance (EMR) method, and an active method.
In the case of the EMR method, the input device includes a coil for inducing electricity by means of an external magnetic field signal. In the active method, the input device may further include a battery.
When the input device is implemented in the capacitive coupling method, the input device may include a conductive tip. Accordingly, when the conductive tip of the input device touches the touch screen of the electronic device or approaches within a predetermined distance, capacitive coupling is achieved between the conductive tip and electrodes in the touch screen.
However, the conductive tip in the related-art input device is often designed to be small in order to input selections very narrowly and precisely. Therefore, there is a problem that coupling capacitance between the conductive tip and the touch screen is so small that transmission and reception efficiency deteriorates.
If a large conductive tip is made to solve this problem, there is a problem that an input point is wrongly recognized when the input device is tilted or otherwise poorly placed.
The above information is presented as background information only, and to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.
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In manufacturing electronic devices, a plasma etching may be performed on a film of a workpiece. A plasma processing apparatus used in the plasma etching may be a capacitively coupled plasma processing apparatus. Generally, the capacitively coupled plasma processing apparatus includes a processing container, a placing table, an upper electrode, and a gas supply unit. The placing table includes a lower electrode, and is configured to support the workpiece within the processing container. The upper electrode is provided above the placing table. The gas supply unit is configured to supply a gas into the processing container. In the capacitively coupled plasma processing apparatus, a processing gas is supplied into the processing container from the gas supply unit, and the processing gas is excited by a high frequency electric field formed between the upper electrode and the lower electrode. Accordingly, plasma is generated. Then, the film of the workpiece is etched by active species of molecules and/or atoms constituting the processing gas.
The capacitively coupled plasma processing apparatus may include a plurality of electromagnets above the upper electrode. For example, the plurality of electromagnets are formed of a plurality of coils provided coaxially around a central axis passing through the center of the placing table in the vertical direction. Alternatively, the plurality of electromagnets are arranged along a plurality of concentric circles around the central axis and in the radial direction. Each electromagnet includes a coil provided around the axis extending in the vertical direction. The plurality of electromagnets are used to adjust a diametric distribution of the density of the plasma generated within the processing container, thereby adjusting a distribution of the etching rate in the diametric direction of the film of the workpiece. The etching of the film using such a plasma processing apparatus is described in, for example, Japanese Patent Laid-Open Publication No. 2014-158005.
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An electronic device can include electrical elements that are both electrically connected to and physically attached to a base component, substrate, or other portion of the electronic device. For example, a plurality of electrically conductive probes can be attached to a testing device configured to contact electronic components, such as semiconductor dies, to test the components. As another example, a plurality of electrically conductive spring contact structures can be attached to opposite sides of a substrate forming an interposer device. As yet another example, electrically conductive contact structures can be attached to terminals (e.g., bond pads) of a singulated semiconductor die or a plurality of dies that are part of an unsingulated semiconductor wafer. As still another example, electric circuit elements (e.g., capacitors, resistors, diodes, switches, transistors, integrated circuit chips, etc.) can be attached to a wiring substrate (e.g., a printed circuit board). In the foregoing examples as well as other instances of an electronic device with attached electrical elements, there can be many such elements. The failure of even one such element can cause the electronic device to fail to function properly. In some instances, however, the cost of the damaged electrical element can be a small fraction of the total cost or value of the electronic device. It has been difficult, however, to repair a single damaged electrical element, particularly where the electrical element is small and/or one of many such electrical elements. Indeed, where many electrical elements are located close together and the damaged electrical element is surrounded by other such electrical elements, it can be particularly difficult to remove and replace the damaged electrical element, particularly if the damaged electrical element is surrounded by others of the electrical elements.
Moreover, even if the electrical element is not surrounded by other electrical elements, it may nevertheless be difficult to attach a replacement electrical element to the electronic device. For example, electrically conductive terminals or traces to which the damaged electrical element was attached may have been fully or partially removed with the damaged electrical element. It can be difficult, impractical, or impossible to attach the replacement electrical element to the electronic device with solder or similar materials. For example, it can be difficult, impractical, or impossible to attach a replacement electrical element to a ceramic substrate with solder or similar materials. As another example, even if solder or similar materials can be used to attach the replacement electrical element to the electronic device, heating the electronic device sufficiently to melt the solder or similar materials to attach the replacement electrical element can also melt solder or similar materials that attach other electrical elements to the electronic device, which can loosen or otherwise damage those other electrical elements and/or the attachment of those electrical elements to the electronic device. Indeed, for the foregoing and other reason, a soldering process can be difficult to control.
Where the electrical element is a spring contact structure configured to make pressured-based electrical connections with another electronic component by being pressed against terminals of the other electronic component, the foregoing difficulties can be particularly acute. In fact, a replacement spring contact structure typically should not only be electrically connected to the electronic device but should also be physically attached to the electronic device with sufficient adhesion strength to withstand forces that arise when the replacement spring contact, with the other spring contacts attached to the device, are pressed against the other electrical component. Regardless of whether the electrical element is a spring contact, an electric circuit element, or another type of electrical element, a process by which a damaged individual one or ones of the electrical elements can be repaired or replaced can allow for the repair of the electrical device. In some instances, such a process can be simple and inexpensive and can result in the electrical device having one or more replacement electrical elements that are securely attached and electrically connected to the electronic device.
An electronic device, for example, like any of the electronic devices mentioned above, can include a substrate on there which are one or more electrically conductive traces, terminals, and/or pads. For example, such traces, terminals, or pads can comprise thin, electrically conductive material (e.g., a conductive metal) deposited or otherwise formed or placed on the substrate. Such a trace, terminal, or pad can become damaged or be fully or partially detached. In some instances, depositing or otherwise forming conductive material on the substrate to repair or replace the damaged or detached trace, terminal, or pad can be difficult, costly, or otherwise impractical or impossible to accomplish. For example, it can be difficult, impractical, or impossible to deposit conductive material on a ceramic substrate to repair a trace, terminal, or pad on the ceramic substrate. A process by which a damaged or detached trace, terminal, or pad or multiple traces, terminals, or pads on a substrate can be repaired or replaced can allow for the repair of an electrical device that includes such a substrate.
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The present application relates to motor drive circuits and the like, and more particularly to thyristor switching devices integrated with an antiparallel diode.
Note that the points discussed below may reflect the hindsight gained from the disclosed inventions, and are not necessarily admitted to be prior art.
Thyristors have long been used for motor control and other high voltage applications. A thyristor is a semiconductor device which has fully bipolar conduction, i.e. both electrons and holes conduct current in the ON-state. By contrast, a simple MOS transistor is a purely unipolar device, i.e. the current is carried entirely (or almost entirely) by electrons in an n-type device. An IGBT (integrated gate bipolar transistor) is a partly bipolar device, in which both carrier types carry current, but the electron current is typically greater than the hole current.
The big difficulty with thyristor circuits is that a thyristor will latch, i.e. once it is turned on it will stay on for as long as voltage across it is enough to cause current to flow. A class of thyristors known as MOS-controlled thyristors (MCTs) provides a thyristor which can be both turned on and turned off by a relatively small signal applied to a gate electrode. The thyristor is a completely bipolar device, and electrons and holes are both emitted from junctions near opposite faces of the semiconductor material. Further information on MOS-controlled thyristors can be found in e.g. issued U.S. Pat. No. 7,705,368 to Rodov and Akiyama, which is commonly owned with the present application.
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The instant invention relates generally to a digital impedance measurement systems and, in particular, to a digital eddy current proximity system for analyzing and monitoring rotating and reciprocating machinery.
Analog eddy current proximity systems which analyze and monitor rotating and reciprocating machinery are known in the art. These analog systems typically include a proximity probe located proximate a target object (e.g., a rotating shaft of a machine or an outer race of a rolling element bearing) being monitored, an extension cable and analog conditioning circuitry. The target, proximity probe (a noncontacting device which measures displacement motion and position of an observed conductive target material relative to the probe), extension cable and conditioning circuitry components are all designed to interact in such a way that a voltage output from the circuitry is directly proportional to a distance between the probe and the target. This distance is commonly referred to as xe2x80x9cgapxe2x80x9d.
The interaction that takes place between these components is in accord with the following rules: First, the electrical impedance measured at the conditioning circuitry is the electrical combination of the target, the probe including an integral sensing coil and cable, the extension cable and the conditioning circuitry. This impedance is usually called the xe2x80x9cTank Impedancexe2x80x9d or parallel impedance (Zp). Second, this tank impedance is linearized and converted into a voltage directly proportional to gap. Third, the conditioning circuitry measures impedance at a specific frequency that is a function of its own circuitry. Generally, the circuitry runs at the frequency where the reactive component of the tank impedance approaches zero. In other words, the circuitry is a resonant system, so the frequency of operation will be where the phase shift of the impedance is approximately zero degrees. In reality, the phase shift is not exactly zero due to, inter alia, manufacturing and component variations and tolerances of each analog system.
In order to compensate for these variations and tolerances, each analog system is required to be calibrated to have a parallel impedance which is as close as possible to a predefined ideal parallel impedance while remaining substantially unsusceptible to the multitude of variations and tolerances found in the target, probe, extension cable, and conditioning circuitry. Simultaneously, each analog system is calibrated to have a maximum sensitivity to changes in gap. Moreover, each system is generally required to be calibrated to monitor one specific target material.
These analog systems are also generally burdened by temperature variations in the target, the probe including the integral sensing coil and cable, the extension cable and the conditioning circuitry due to the severe temperature variations in rotating and reciprocating machinery environments. Thus, each system is required to be designed around a multitude of component tolerances to compensate for the severe temperature variations engendered in these environments. Furthermore, these analog systems must also be designed around the sensitivity to changes in the conductivity and permeability of the target, the sensing coil, and the cable, which can greatly effect the precision of these systems.
Moreover, interchangeability problems arise from variations in the target, probe, extension cable, and conditioning circuitry which cause the tank impedance (Zp) versus gap to vary slightly from nominal resulting in a proclivity towards, inter alia, variations in incremental scale factor (ISF), variations in average scale factor (ASF) and deviations from a straight line (DSL). The incremental scale factor (ISF), variations in average scale factor (ASF) and deviations from a straight line (DSL) are common ways to specify transducer performance as is well known in the art.
It is critical that the displacement motion or position between the target and the sensing coil of the proximity probe remains within the linear range of the proximity probe for providing accurate and reliable measurements over a wide range of circuit and environmental conditions in order to operate rotating and reciprocating machinery safely and efficiently. Heretofore, the ability to provide accurate and reliable measurements over a wide range of circuit and environmental conditions has been dependent on, inter alia, designing and manufacturing each production unit within close tolerances and going through laborious calibration methods to compensate for the circuit and environmental conditions.
For the foregoing reasons, there is a need for an eddy current transducer system that, inter alia, substantially eliminates the manufacturing and component variations and tolerances of the prior art analog systems, a system that provides correct gap reading for different target materials and a system which is easy to calibrate.
Additionally, there is a need to solve the general problem of compensating for temperature errors, temperature profiles of different target materials and changes in component conductivity and permeability in order to preclude anomalous behavior in eddy current transducer systems.
Furthermore, there is a need for an eddy current transducer system that has better linearity and interchangeability. Moreover, there is a need for an eddy current transducer system that does not require component changes when re-calibrated to a new or different target material.
The instant invention is distinguished over the known prior art in a multiplicity of ways. For one thing, the instant invention provides a unique digital system for digitally measuring an unknown electrical impedance. Additionally, the instant invention provides a digital proximity system that is a direct one for one replacement for existing analog eddy current proximity systems which is compatible with any existing (or future) eddy current proximity probe (a noncontacting device which measures displacement motion and position of an observed conductive or metallic target material relative to the probe) and extension cable assembly. Thus, the instant invention can directly replace the analog conditioning circuitry of prior art analog systems thereby eliminating the anomalies associated with manufacturing and component variations, and tolerances of these systems. Furthermore, the instant invention eliminates the laborious design and calibration methods required to calibrate prior art analog systems in order to compensate for manufacturing and component variations, tolerances and environmental conditions.
In one form, the instant invention provides a system which includes a unique voltage ratio apparatus and method for digitally measuring an unknown electrical component value. The system accomplishes this by digitizing a first voltage impressed across a serial coupling of a first electrical component and a second electrical component, and by digitizing a second voltage impressed across the second electrical component only. Each of the two digitized voltages is then convolved with digitized waveforms to obtain a first and a second complex voltage number. A ratio of the second complex number to a difference between the first and the second complex number is determined and multiplied by a known value of the first electrical component to determine the unknown value of the second electrical component. A resistance means having a known value can be employed as the first electrical component. The second electrical component can take the form of a proximity probe having an unknown impedance value which, when determined by the instant invention, can be correlated to a distance between the probe and a metallic target object being monitored by the probe. Iteratively repeating the voltage ratio method results in continuously digitally determining the unknown impedance values of the probe which can be directly correlated to the continuous displacement motion and position of the target being monitored relative to the probe. In one form, the digitally determined impedance values can be transformed into analog signals and used to trip alarms, circuit breakers, etc., when the signals are outside nominal operating ranges set by plant operators.
Additionally, the instant invention provides a system that can be used as a direct one for one replacement for existing (and future) analog eddy current proximity systems. The system includes a unique apparatus and method for digitally measuring the impedance of a proximity probe and an extension cable (if employed) which includes the unique voltage ratio apparatus and method delineated supra to obtain an unknown impedance of the proximity probe. Then, the system mirrors a circuit equivalent impedance of an existing (or future) analog proximity circuit and combines the measured impedance with the circuit equivalent impedance for defining a parallel or tank impedance. The defined tank impedance is then correlated to a distance between the probe and a metallic target object being monitored by the probe. Hence, the system can continuously digitally determine the unknown impedance value of the probe by iteratively repeating the aforementioned method and then correlate the digitally measured probe impedance values to the continuous displacement motion and position of the target for analyzing and monitoring rotating and reciprocating machinery.
More particularly, the instant invention provides a system which employs at least one eddy current proximity probe having a multi-axial probe cable coupled to a sensing coil located proximate a conductive target to be monitored. The sensing coil is coupled to ground and to a second terminal of a resistor via the probe cable and an extension cable (if employed). A first terminal of the resistor is coupled to a signal generator device that is digitally programmable to generate dynamic driving signals.
The signal generator device can be included in a digital feedback loop which includes means for monitoring the phase of the tank impedance and to provide corrective action (a frequency change) for adjusting that phase. Thus, the signal generator device can be digitally programmed to emulate the operating frequency of any previous (or future) analog proximity system and can also be digitally reprogrammed, in real time, for driving the sensing coil of the probe at one or more frequencies corrective of any anomalous phase shift calculated from the probe or tank impedance or due to any other anomalies within the system. For example, the instant invention can drive the sensing coil at a precise frequency corrective of temperature variations in the probe including the integral sensing coil and probe cable, and in the target.
A filter is interposed between the signal generator device and the first terminal of the resistor to purify the output dynamic signals of the signal generator device by eliminating, inter alia, harmonics that are created in the device. In addition, the filter helps reduce the noise bandwidth of the system which improves a signal to noise ratio. The filtered signal is driven through the resistor, extension cable (if employed), probe cable and coil for inducing eddy currents within the target. In turn, the eddy currents in the target induce a voltage in the sensing coil of the probe and hence, a change in an impedance of the probe and extension cable (if employed) which varies as a function of, inter alia, the displacement motion and position of the target relative to the probe.
The first and second terminals of the resistor are coupled to inputs of a first and a second analog to digital converter respectively. In turn, the outputs of the analog to digital converters are coupled to a digital signal processor including a convolution means. The first analog to digital converter receives and samples a first voltage between the serially coupled resistor, extension cable (if employed), probe cable and coil and outputs a first digital voltage signal to the digital signal processor. The second analog to digital converter receives and samples the voltage between ground and the combination of the extension cable (if employed), the probe cable and the coil and then, outputs a second digitized voltage signal to the digital signal processor. A timing control means is operatively coupled to the analog to digital converters and to the signal generator device such that the sampling is synchronously performed with the driving signal of the signal generator. This ensures, inter alia, that when the voltages are calculated there will be exactly one cycle worth of data stored in each data set.
The digital signal processor convolves the two digitized voltages by convolving each digitized voltage with a digital sine and cosine wave to obtain a first and a second complex voltage number. Once the convolution of the digitized voltages is performed the impedance value of the extension cable (if employed), probe cable and coil can be calculated directly from the measured voltages.
The system includes an open/short/load calibration method which can compensate for cable length included in the second electrical component. For example, the extension cable can be compensated for by using the open/short/load calibration method according to the instant invention. Thus, the system can apply the open/short/load calibration method to the measured impedance to obtain a compensated impedance. Furthermore, the open/short/load calibration method can be utilized to calibrate each printed wire assembly within the system.
The measured impedance or the compensated impedance is then correlated by the system to a gap value by using equations, numerical methods, algorithmic functions or lookup tables wherein gap values are correlated to measured or compensated impedance values defining the gap or spacing interposed between the probe and the target being monitored. This method of measuring gap can be continuously repeated for monitoring, for example the vibration of a rotating shaft of a machine or an outer race of a rolling element bearing.
Additionally, the system can combine the measured impedance or the compensated impedance value with a mathematical model value or an empirically predetermined value of an existing (or future) analog conditioning circuit that is compatible with the particular probe being employed. This value can be called up from a memory means associated with the digital signal processor. The digital signal processor combines this value with the measured impedance or the compensated impedance to obtain a resultant impedance defined as the tank impedance. This tank impedance can be employed to determine the gap between the probe and the target by using equations, numerical methods, algorithmic functions or lookup tables wherein gap values are correlated to tank impedance values. Thus, the existing proximity probe can be retained and this method of measuring gap can be continuously repeated for monitoring, for example the vibration of a rotating shaft of a machine or an outer race of a rolling element bearing that was heretofore monitored by an analog eddy current proximity system.
Gap values can be outputted to a digital to analog converter for providing analog outputs or downloaded to a processing stage for further processing and/or providing digital and/or analog outputs.
The impedance value of analog conditioning circuitry determined from the mathematical model or empirically is typically dependent on operating frequency. Thus, once the tank impedance is determined it can be used to determine if the system is running at the proper frequency. If the system is not running at the proper frequency the digital feedback loop can be used to feedback a signal from the digital signal processor to program the signal generator device for dynamically adjusting the driving signal.
Moreover, the instant invention includes a unique material identification method for automatically identifying a target material and automatically calibrating itself to monitor the identified material thereby eliminating the need for component changes and laborious re-calibration methods inherent with prior art systems. The instant invention also expands the unique material identification method to include a material insensitive method which is capable of outputting a gap value substantially correct for any target material being monitored thereby providing a material insensitive digital proximity system. Thus, the instant invention provides a digital proximity system that does not require component changes when being used to replace an existing system and/or does not require re-calibration when being used with a new or different target material. As a result, the instant invention provides a digital proximity system which can not be mis-calibrated when put into operation and which eliminates the interchangeability problem found in prior art systems.
Additionally, the instant invention includes a unique inductive ratio method which allows a gap versus inductive ratio curve to be determined for a specific target material without knowing the far gap impedance of the probe coil and thus, without removing the probe from a machine being monitored. The gap versus inductive ratio curve determined by this method can be used to determine the gap between the probe and the target being monitored. Furthermore, this method can be used to discern moisture ingress within a probe while it is still in the machine.
Accordingly, a primary object of the instant invention is to provide a new, novel and useful digital eddy current proximity system: apparatus and method.
Another further object of the instant invention is to provide is to provide a new, novel and useful digital system for measuring an unknown electrical value of an electrical component, for example, an unknown impedance value of an electrical component thereby providing a digital impedance measuring device.
Another further object of the instant invention is to provide a digital proximity system as characterized above which includes the digital impedance measuring device employed to measure impedance of an eddy current displacement probe and correlate the measured impedance to a gap between the probe and a target being monitored.
Another further object of the instant invention is to provide a digital proximity system as characterized above which includes means to dynamically measure the impedance of an eddy current probe at bandwidths high enough to support vibration information.
Another further object of the instant invention is to provide a digital proximity system as characterized above which provides a digital proximity system that is compatible with previous (or future) analog eddy current systems and existing signal conditioning sensors including proximity sensors using one or more frequencies.
Another further object of the instant invention is to provide a digital proximity system as characterized above which is capable of emulating the operation of analog conditioning circuitry of eddy current proximity systems for providing backwards (or future) compatibility with analog systems.
Another further object of the instant invention is to provide a digital proximity system as characterized above which includes an open/short/load calibration method which allow various cable length compatibility.
Another further object of the instant invention is to provide a digital proximity system as characterized above which includes a unique automatic material identification and calibration method.
Another further object of the instant invention is to provide a digital proximity system as characterized above which includes a unique material insensitive method.
Another further object of the instant invention is to provide a digital proximity system as characterized above which includes a unique inductive ratio method for measuring gap values.
Another further object of the instant invention is to provide a digital proximity system as characterized above which is self-contained, self-configuring and self-analyzing.
Another further object of the instant invention is to provide a digital proximity system as characterized above which is capable of identifying an eddy current displacement probe that is coupled thereto.
Viewed from a first vantage point, it is an object of the instant invention to provide a device for digitally measuring electrical impedance, comprising in combination: a network including a first electrical component and a second electrical component serially connected; a signal generating means operatively coupled to the network for driving a current through the serially connected components; means for sampling a first voltage impressed across the network and a second voltage impressed across the second component into digitized voltages; means for convolving each the digitized voltage with a digital waveform for forming a first complex number and a second complex number correlative to the first voltage impressed across the network and the second voltage impressed across the second component respectively; means for determining a ratio of the second complex number to a difference between the first and the second complex number, and means for calculating an electrical impedance of the second component by multiplying the ratio by a value of the first component wherein the electrical impedance of the second component is digitally measured.
Viewed from a second vantage point, it is an object of the instant invention to provide a method for digitally measuring electrical impedance, the steps including: forming a network including providing a first electrical component and a second electrical component serially connected; driving the network with a dynamic signal for impressing a voltage across the network and each component; digitizing the voltage across the network and the voltage across the second electrical component; convolving each of the digitized voltages with a digital waveform for forming a first complex number and a second complex number correlative to the voltages across the network and across the second electrical component respectively; determining a ratio of the second complex number to a difference between the first complex number and the second complex number; calculating an electrical impedance of the second electrical component by multiplying the ratio by a know digitized value of the first electrical component wherein the electrical impedance of the second component is digitally measured.
Viewed from a third vantage point, it is an object of the instant invention to provide an apparatus for determining a gap between a proximity probe and a conductive target material, the apparatus comprising in combination: a network including a first electrical component and a proximity probe serially connected; a signal generating means operatively coupled to the network for driving a current through the serial connection wherein a first analog voltage is impressed across the network and a second analog voltage is impressed across the proximity probe; means for sampling and digitizing the first analog voltage impressed across the network and the second analog voltage impressed across the proximity probe into digitized voltages; means for convolving each the digitized voltage with a digital waveform for forming a first complex number and a second complex number correlative to the first analog voltage impressed across the network and the second analog voltage impressed across the proximity probe respectively; means for determining a voltage ratio of the second complex number to a difference between the first complex number and the second complex number; means for processing the voltage ratio into a gap value correlative to a gap between the proximity probe and a conductive target material.
Viewed from a fourth vantage point, it is an object of the instant invention to provide an apparatus for determining a gap between a proximity probe and a conductive target material, the apparatus comprising in combination: a network including an extension cable interposed between and serially connected to a first electrical component and a proximity probe; a signal generating means operatively coupled to the network for driving a current through the serial connection wherein a first analog voltage is impressed across the network and a second analog voltage is impressed across the serial connection of the extension cable and the proximity probe; means for sampling and digitizing the first analog voltage impressed across the network and the second analog voltage impressed across the serial connection of the extension cable and the proximity probe into digitized voltages; means for convolving each the digitized voltage with a digital waveform for forming a first complex number and a second complex number correlative to the first analog voltage impressed across the network and the second analog voltage impressed across the serial connection of the extension cable and the proximity probe respectively; means for determining a voltage ratio of the second complex number to a difference between the first complex number and the second complex number; means for processing the voltage ratio into a gap value correlative to a gap between the proximity probe and a conductive target material.
Viewed from a fifth vantage point, it is an object of the instant invention to provide an apparatus for determining a dynamic gaps between a proximity probe and a conductive target material, the apparatus comprising in combination: means for establishing dynamic voltage signals correlative to dynamic gaps between a proximity probe and a conductive target material; sampling means for digitizing the established dynamic voltage signals into digital voltage signals; a digital multiplier for multiplying each the digital voltage signal by a digital sine signal and a digital cosine signal; means for accumulating values of each multiply in a memory, and means for processing each multiply for obtaining complex voltage representations correlative to dynamic gaps between the proximity probe and a conductive target material.
Viewed from a sixth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the method including the steps of: providing a network of components including a first electrical component and a proximity probe component serially connected; driving a dynamic current through the serially connected electrical components for impressing a first analog voltage across the network and a second analog voltage cross the proximity probe component; sampling and digitizing the first analog voltage impressed across the serially connected resistance and probe components to obtain a first digitized voltage value; sampling and digitizing a second analog voltage impressed across the probe component to obtain a second digitized voltage value; digitally convolving the first digitized voltage and the second digitized voltage into a first complex number and a second complex number respectively; calculating a voltage ratio of the second complex number to a difference between the first complex number and the second complex number; processing the voltage ratio into a gap value correlative to a gap between the proximity probe and a conductive target material.
Viewed from a seventh vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the method including the steps of: providing a network of components including a first electrical component and a proximity probe component serially connected; driving a dynamic current through the serially connected electrical components including the resistance component and the proximity probe component for impressing a first analog voltage across the network and a second analog voltage cross the proximity probe component; sampling and digitizing the first analog voltage impressed across the serially connected resistance and probe components to obtain a first digitized voltage value; sampling and digitizing a second voltage impressed across the probe component to obtain a second digitized voltage value; digitally convolving the first digitized voltage and the second digitized voltage into a first complex number and a second complex number respectively; calculating a voltage ratio of the second complex number to a difference between the first complex number and the second complex number; multiplying the voltage ratio by a value of the first electrical component for determining an impedance of the proximity probe; correlating the determined impedance of the proximity probe to a gap between the proximity probe and a conductive target material.
Viewed from a eighth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the method including the steps of: providing a network of components including a first electrical component, an extension cable component and a proximity probe component respectively serially connected, and locating the proximity probe adjacent a conductive target material; driving a dynamic current through the serially connected electrical components for impressing a first analog voltage across the network and a second analog voltage across the serial connection of the extension cable component and the proximity probe component; sampling and digitizing the first analog voltage impressed across the network to obtain a first digitized voltage value; sampling and digitizing a second analog voltage impressed across the serial connection of the extension cable component and the proximity probe component to obtain a second digitized voltage value; digitally convolving the first digitized voltage value and the second digitized voltage value into a first complex number and a second complex number respectively; calculating a voltage ratio of the second complex number to a difference between the first complex number and the second complex number; processing the voltage ratio into a gap value correlative to a gap between the proximity probe and the conductive target material.
Viewed from a ninth vantage point, it is an object of the instant invention to provide a method for measuring a position of a conductive target material, the steps including: sampling and digitizing a first voltage impressed across a serial connection of a resistance means and a proximity probe located adjacent a conductive target material to obtain a first digitized voltage; sampling and digitizing a second voltage impressed only across the probe to obtain a second digitized voltage, transforming the two digitized voltages into complex voltage numbers; calculating an electrical impedance of the proximity probe by using both complex voltage numbers; correlating the calculated electrical impedance to a gap between the proximity probe and the conductive target material.
Viewed from a tenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: sampling and digitizing a first voltage impressed across a serial connection of a first electrical component and a proximity probe located adjacent a conductive target material to obtain a first digitized voltage; sampling and digitizing a second voltage impressed across the probe to obtain a second digitized voltage, transforming the two digitized voltages into complex voltage numbers; determining an electrical impedance of the proximity probe by using both complex voltage numbers; normalizing the electrical impedance of the proximity probe; correlating the normalized electrical impedance of the proximity probe to a gap between the proximity probe and the conductive target material.
Viewed from a eleventh vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: sampling and digitizing a first voltage impressed across a serial connection of a first electrical component, an extension cable and a proximity probe located adjacent a conductive target material to obtain a first digitized voltage; sampling and digitizing a second voltage impressed across the probe to obtain a second digitized voltage, transforming the two digitized voltages into complex voltage numbers; determining an electrical impedance of the proximity probe by using both complex voltage numbers and compensating for the extension cable; normalizing the electrical impedance of the proximity probe; correlating the normalized electrical impedance of the proximity probe to a gap between the proximity probe and the conductive target material.
Viewed from a twelfth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the method including the steps of: digitally measuring an electrical impedance of a proximity probe located adjacent a conductive target material; combining a predetermined digitized impedance with the digitally measured impedance of the proximity probe; correlating the combined impedance to a gap interposed between the proximity probe and the conductive target material being monitored.
Viewed from a thirteenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the method including the steps of: digitally measuring an electrical impedance of an a proximity probe and an extension cable connected thereto, the proximity probe is located adjacent a conductive target material; combining a predetermined digitized impedance with the digitally measured impedance; correlating the combined impedance to a gap interposed between the proximity probe and the conductive target material being monitored.
Viewed from a fourteenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the method including the steps of: measuring an impedance of a proximity probe located proximate a conductive target material and an extension cable operatively coupled to the proximity probe; compensating the measured impedance by using compensation coefficients stored in a memory means; combining a predetermined impedance with the compensated measured impedance for forming a combination impedance; determining a gap between the proximity probe and the conductive target material as a function of the combination impedance; iteratively repeating the measuring, compensating, combining and determining steps to substantially continuously monitor the gap between the probe and the target as a function of the combination impedance.
Viewed from a fifteenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: providing a database of normalized impedance curve representations for different conductive target materials; measuring an impedance of a proximity probe located proximate a conductive target material being identified; normalizing the measured probe impedance; utilizing the normalized probe impedance and the database of normalized impedance curve representations for identifying the conductive target material; determining a gap value between the proximity probe and the conductive target material from the normalized probe impedance and the identified target material.
Viewed from a sixteenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: providing a representation of a defined series of gap locus each representative of the same gap for different target materials; measuring an impedance of a proximity probe located proximate a conductive target material; normalizing the measured probe impedance; determining a gap value between the proximity probe and the conductive target material from the normalized probe impedance and the representation of the defined series of gap locus wherein the gap value is substantially correct for any conductive target material adjacent the proximity probe thereby providing a material insensitive method for measuring gap values between the proximity probe and different conductive target materials.
Viewed from a seventeenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: providing a representation of a defined series of gap locus each representative of the same gap for different target materials; measuring an impedance of a proximity probe located proximate a conductive target material, the proximity probe including a probe cable; compensating an impedance contribution of the probe cable from the measured probe impedance to define a measured coil impedance; normalizing the measured coil impedance; determining a gap value between the proximity probe and the conductive target material from the normalized coil impedance and the representation of the defined series of gap locus wherein the gap value is substantially correct for any conductive target material adjacent the proximity probe thereby providing a material insensitive method for measuring gap values between the proximity probe and different conductive target materials.
Viewed from a eighteenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: measuring a proximity probe impedance at a first frequency and a second different frequency, the proximity probe including an integral sensing coil; determining an impedance of the sensing coil from the measured proximity probe impedance at the first frequency and the second different frequency; dividing a reactance of the impedance of the sensing coil at the first frequency by the reactance of the impedance of the sensing coil at the second different frequency for defining an inductive ratio; correlating the inductive ratio to a value representative to a gap between the proximity probe and the conductive target material.
Viewed from a nineteenth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: sampling and digitizing a first voltage impressed across a serial connection of a resistance means and a proximity probe located adjacent a conductive target material to obtain a first digital voltage correlative to the first voltage at a first frequency; sampling and digitizing a second voltage impressed only across the probe to obtain a second digital voltage correlative to the second voltage at the first frequency, digitally convolving the first digital voltage and the second digital voltage into a first complex voltage number and a second complex voltage number; calculating an electrical impedance of the proximity probe at the first frequency by using the first complex voltage number and the second complex voltage number; sampling and digitizing a third voltage impressed across the serial connection of the resistance means and the proximity probe located adjacent the conductive target material to obtain a third digital voltage correlative to the third voltage at a second frequency; sampling and digitizing a fourth voltage impressed only across the probe to obtain a fourth digital voltage correlative to the fourth voltage at the second frequency, digitally convolving the third digital voltage and the fourth digital voltage into a third complex voltage number and a fourth complex voltage number; calculating a complex electrical impedance of the proximity probe at the second frequency by using the third complex voltage number and the fourth complex voltage number; dividing a reactance of the calculated complex electrical impedance of the sensing coil at the first frequency by the reactance of the calculated complex electrical impedance of the sensing coil at the second different frequency for defining an inductive ratio; correlating the inductive ratio to a value representative to a gap between the proximity probe and the conductive target material.
Viewed from a twentieth vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: providing a proximity probe having a first end located adjacent a conductive target material and having a second end coupled to a first end of an extension cable; measuring an impedance at a second end of the extension cable; compensating the measured impedance by mathematically eliminating extension cable residuals from the measured impedance for defining a proximity probe impedance of the proximity probe; correlating the proximity probe impedance with a value representative of a gap between the proximity probe and the conductive target material.
Viewed from a twenty-first vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: providing an extension cable having two ends; determining a first impedance of the extension cable with one of the two ends opened for defining an open impedance; determining a second impedance of the extension cable with one of the two ends shorted for defining a short impedance; providing a proximity probe having an end located adjacent a conductive target material and having an opposite end coupled to one of the two ends of the extension cable; measuring an impedance at the other end of the extension cable; determining an impedance of the proximity probe as a function of the short impedance, the open impedance and the measured impedance for defining a proximity probe impedance; correlating the proximity probe impedance with a value representative of a gap between the proximity probe and the conductive target material.
Viewed from a twenty-second vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: providing an extension cable having two ends; determining a first impedance of the extension cable with one of the two ends opened for defining a open impedance; determining a second impedance of the extension cable with one of the two ends shorted for defining a short impedance; determining a third impedance of the extension cable with one of the two ends coupled to a load having a known value for defining a load impedance; providing a proximity probe having an end located adjacent a conductive target material and having an opposite end coupled to one of the two ends of the extension cable; measuring an impedance at the other end of the extension cable; determining an impedance of the proximity probe as a function of the short impedance, the open impedance, the load impedance and the measured impedance for defining the proximity probe impedance; correlating the proximity probe impedance with a value representative of a gap between the proximity probe and the conductive target material.
Viewed from a twenty-third vantage point, it is an object of the instant invention to provide a method for measuring a gap between a proximity probe and a conductive target material, the steps including: providing an extension cable having two ends; determining a first load impedance of the extension cable with one of the two ends coupled to a first load; determining a second load impedance of the extension cable with one of the two ends coupled to a second load; the second load having an impedance that is less than the impedance of the first load; providing a proximity probe having an end located adjacent a conductive target material and having an opposite end coupled to one of the two ends of the extension cable; measuring an impedance at the other end of the extension cable; calculating a proximity probe impedance of the proximity probe as a function of the measured impedance, the first load impedance and the second load impedance for compensating for extension cable residuals; correlating the proximity probe impedance with a value representative of a gap between the proximity probe and the conductive target material.
Viewed from a twenty-fourth vantage point, it is an object of the instant invention to provide a method for measuring a characteristic of a conductive target material disposed adjacent a proximity probe, the steps including: providing a length of cable having a first end and a second end; determining a first impedance of the cable with the first end opened for defining a open impedance; determining a second impedance of the cable with the first end shorted for defining a short impedance; coupling the first end of the cable to a proximity probe and having the second end of the cable coupled to a digital eddy current proximity system; measuring, at the second end of the cable, an impedance of the coupled cable and proximity probe; calculating the proximity probe impedance as a function of the measured impedance, the open impedance, and the short impedance for compensating for cable length residuals; correlating the proximity probe impedance with a characteristic of a conductive target material disposed adjacent the proximity probe.
These and other objects and advantages will be made manifest when considering the following detailed specification when taken in conjunction with the appended drawing figures.
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{
"pile_set_name": "USPTO Backgrounds"
}
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