A patient-specific finite element model of the cornea is generated for the purposes of modeling a cornea for simulating tissue cuts in the cornea. A first group of tissue fibers, with main fibers that extend parallel to the surface of the cornea, is distributed in the finite element model in accordance with a first distribution function. Moreover, a second group of tissue fibers, with inclined cross-linked fibers that do not extend parallel to the surface of the cornea, is distributed in the finite element model in accordance with a second distribution function. Here, the second distribution function distributes the cross-linked fibers with a non-uniform weighting function over the depth of the cornea, from the outer surface of the cornea to the inner surface of the cornea.

1. Field of the Invention
The present invention relates to a device and a method for modeling a cornea. In particular, the present invention relates to a computerized device and a computer-implemented method for modeling a cornea for simulating tissue cuts in the cornea, wherein the computerized device comprises a processor programmed to generate a patient-specific finite element model of the cornea.
2. Description of the Prior Art
A plurality of refractive errors such as myopia (shortsightedness), hyperopia (farsightedness) or astigmatism are corrected these days by means of surgical interventions on the eye. Here, the refractive correction of the eye is predominantly brought about by means of ophthalmological laser systems, which cut and/or ablate the eye tissue, in particular the cornea, in order to approximate the optical refractive power of the eye as closely as possible to a desired value. Although tissue cuts can be carried out very precisely by means of laser pulses—much more accurately compared to e.g. manually using a scalpel—the change in the tissue form emerging in the case of tissue cuts as a result of the intraocular pressure makes the planning of cuts and the prediction of cut results nevertheless very difficult.
In order to improve the ophthalmic refractive correction, WO 02/07660, WO 94/18636, US 2009/318907 and US 2009/187386 describe the modeling of the eye using finite element analysis. Here, the finite element model of the eye can be used for simulating tissue cuts. WO 02/07660 describes the introduction of a layer model of the cornea with a plurality of layers with different strengths. US 2009/318907 and US 2009/187386 describe a general axis-symmetrical model based on a nonlinear elastic, slightly compressible and transversely isotropic formulation. US 2009/187386 moreover describes a connection of the cornea to the sclera with pre-programming of peripheral elements for imaging a secure connection of the cornea to the sclera (limbus), which may not be sufficient in the case of cuts which extend beyond the cornea into the adjacent sclera. Moreover, the known solutions provide no indications as to how the stromal swelling pressure is included in the modeling.
In recent years, the inhomogeneity of the cornea over the depth thereof was examined in great detail, particularly in:    Quantock A J, Boote C, Yount R D, Hayes S, Tanioka H, Kawasaki S, Ohta N, Iida T, Yagi N, Kinoshita S, Meek K M, (2007); "Small-angle fibre diffraction studies of corneal matrix structure: a depth-profiled investigation of the human eye-bank cornea"; Journal of Applied Crystallography, 40: 335-340;    Palka B P, Tanioka H, Sotozono C, Yagi N, Boote C, Young R D, Meek K M, Quantock A J, (2008); "Reduced collagen interfibrillar spacing in macular corneal dystrophy occurs predominantly in deep stromal layers"; Investigative Ophthalmology & Visual Science, 49: E-Abstract 3926;    Kamma-Lorger C S, Boote C, Young R D, Hayes S, Quantock A J, Meek K M, (2008); "Depth profile study of molecular collagen structure in normal human cornea; Acta Ophthalmologica", 86: 243;    Meek K M, Boote C, (2009); "The use of X-ray scattering techniques to quantify the orientation and distribution of collagen in the corneal stroma"; Progress in Retinal and Eye Research, 28: 369-392;    Kamma-Lorger C S, Boote C, Hayes S, Moger J, Burghammer M, Knupp C, Quantock A J, Sorensen T, Di Cola E, White N, Young R D, Meek K M, (2010); "Collagen and mature elastic fibre organization as a function of depth in the human cornea and limbus"; Journal of Structural Biology, 169: 424-430; and    Petsche S J, Chernayak D, Martiz J, Levenston M E, Pinsky P M, (2012); "Depth-Dependent Transverse Shear Properties of the Human Corneal Stroma"; Investigative Ophthalmology & Visual Science, 53(2): 873-80.
What was identified here is that the tissue becomes ever weaker over the depth thereof, i.e. from the front/outside (anterior) to the back/inside (posterior), and, in particular, that there is a significant reduction in the shearing stiffness. The cause of this was found to lie in the fact that there are many inclined collagen fibers, i.e. collagen fibers that do not extend parallel to the corneal surface, in the front/outer layers. Inclined fibers, or so-called cross-linked fibers, provide the tissue with shearing stiffness. By contrast, the fibers lying properly on one another in layers, extending parallel to the surface, are found in the deep (back/inside) layers.
In the last decade, various mathematical material definitions were established and published for simulating the biomechanical properties of the corneal tissue, particularly in:    Bryant M, McDonnell P, (1996); "Constitutive laws for biomechanical modelling of refractive surgery", Journal of Biomechanical Engineering, 118(4): 473-481;    Pinsky P M, Van der Heide D, Chernyak D, (2005); "Computational modelling of mechanical anisotropy in the cornea and sclera"; Journal of Cataract and Refractive Surgery, 31(1): 136-145;    Alastrue V, Calvo B, Pena E, Doblare M, (2006); "Biomechanical Modelling of Refractive Surgery; Journal of Biomechanical Engineering", 128: 150;    Lanchares E, Calvo B, Cristobal J, Doblare M, (2008); "Finite element simulation of arcuates for astigmatism correction"; Journal of Biomechanics, 41: 797-805;    Pandolfi A, Manganiello F, (2006); "A model for the human cornea: constitutive formulation and numerical analysis"; Biomechanics and Modelling in Mechanobiology, 5(4): 237-246;    Pandolfi A, Holzapfel G, (2008); "Three-dimensional modelling and computational analysis of the human cornea considering distributed collagen fibril orientations"; Journal of Biomechanical Engineering, 130(6); and    Pandolfi A, Fotia G, Manganiello F, (2009); "Finite element simulation of laser refractive corneal surgery"; Engineering with Computers, 25: 15-24.
Generating a patient-specific finite element model of the cornea was described in the document Studer H P, Riedwyl H, Amstutz C A, Hanson V M, Büchler P, (2013) "Patient-specific finite-element simulation of the human cornea: A clinical validation study on cataract surgery"; Journal of Biomechanics, 46(4): 751-758. Here, the effect of cataract incisions on patients was simulated numerically. However, Studer et al. specifically state in this document that neither the material parameters nor the distribution of collagen fibers was patient-specific and that the depth-dependence of mechanical properties within the corneal thickness was also ignored. Moreover, as a conclusion, they noted that taking into account the individual corneal topography of the patient is more relevant to a precise prediction of the post-operative corneal form than a precise determination of patient-specific material properties.
Mathematical material definitions for simulating the biomechanical properties of the corneal tissue, in which the inclined fibers are also taken into account, are only found in the following documents:
Studer H P, Larrea X, Riedwyl H, Büchler P, (2010); "Biomechanical model of human cornea based on stromal microstructure"; Journal of Biomechanics, 43: 836-842; and
Petsche S J, Pinsky P M, (2013); "The role of 3-D collagen organization in stromal elasticity: a model based on X-ray diffraction data and second harmonic-generated images"; Biomechanics and Modelling in Mechanobiology.
Here, in the latter document, Petsche S J and Pinsky P M define a three-dimensional distribution function (all directions are in a spherical coordinate system), which simultaneously models the weighting of the main fibers and inclined fibers. By means of this weighting, the authors describe the amount of collagen fibers that extend in a specific direction. The fibers themselves are described as a material anisotropy in the continuum.

Device and method for modelling a cornea


Aircraft landing gear (100) provided with a bottom portion (110) that is steerable by means of a steering actuator (1) comprising a toothed wheel (70) that is secured to the steerable bottom portion (110) and that co-operates with a rack (20) that is movable in translation along an axial travel axis (X) and that has ends (21a, 21b) connected to pistons (30a, 30b) mounted to slide in respective cylinders (10a, 10b). Each connection between one of the pistons (30a, 30b) and the associated end of the rack (20) presents play (J) at least axially, and possibly also angular play (E), and at least one sealing gasket, referred to as an internal gasket (25), between the rack (20) and a piston (30a, 30b), the gasket being arranged to oppose movements of the rack (20) relative to the pistons (30a, 30b).

Aircraft landing gear is known in which a bottom portion possesses a steering actuator to enable the wheel(s) carried by the landing gear to be steered. In general, the landing gear has a shaft that can be turned relative to a stationary portion of the landing gear that is connected to the airframe of the aircraft. The turnable shaft is connected to the wheel(s) of the landing gear and is secured to a toothed wheel. Turning the toothed wheel enables the turnable shaft to be steered together with the aircraft wheels to which it is connected. The toothed wheel co-operates with a rack that is guided in translation by pistons coupled to the ends of the rack. For this purpose, each of the pistons is slidably mounted in a cylinder that is associated therewith.
In summary, the wheel(s) of the landing gear is/are steered under the control of a steering actuator having pistons that guide a rack to move in translation, which rack drives a toothed wheel secured to the turnable shaft that is in turn connected to the wheel(s) of the landing gear.
By way of example, mention may be made of patent document FR 2 568 218, which describes nose landing gear provided with such a rack actuator.
It has been observed that the teeth of the toothed wheel and/or the teeth of the rack suffer from premature wear.

Aircraft landing gear with orientable lower part


A composition, use of and a method of removing a hyperplastic skin lesion on a mammal comprising administering to the lesion or locus thereof a therapeutically effective amount of a composition comprising a blocker selected from the group consisting of a calcium channel blocker, a metabolite thereof, a calmodulin blocker and a metabolite thereof and a pharmaceutically acceptable diluent or carrier.

Hyperplastic skin lesions, such as calluses, corns, plantar warts, hyperplastic scarring, genital warts, cutaneous warts, skin tags, and the like are potentially infectious, particularly, genital warts which are a sexually transmitted disease. For hygienic, as well as cosmetic reasons, these warts and skin tags frequently need to be removed.
Hyperplastic skin lesions can result from multiple causes. With psoriasis, the mechanism causing hyperplastic thickening of the skin to form psoriatic plaques is unknown, but appears to be a cell mediated autoimmune process. Areas of the skin subject to excessive repetitive trauma from thermal, chemical or physical means can cause thickening and hypertrophy of the stratum Corneum layer of the epidermis to produce callouses and corns, which are most common on the hands and feet from ill-fitting shoes, or repetitive activities related to work or leisure. Chronic infections can also induce hyperplastic scaring especially in certain individuals predisposed to keloids and other forms of scars that are associated with excessive collagen formation. Other know causes of hyperplasia of the skin are viral infections of the skin that also cause a hyperplasia of the epidermal layers to form pathological lesions such as plantar warts, genital warts, cutaneous warts, skin tags, and the like are potentially infectious, particularly, genital warts which are a sexually transmitted disease. For hygienic, functional, comfort, as well as cosmetic reasons, a safe and painless method for treating these medical conditions associated with hyperplasia of the skin need to be removed/treated.
Any suitable antagonist, generally, of neuronal voltage-dependent Ca.sup.++ channels may be used to reduce or prevent AIDS related vision loss, myelopathy, or dementia. Examples are Nifedipine, mioflazine, flunarizine, bepridil, lidoflazine, Ranolazine, Nisoldipine, Nicardipine, PN200-110, Felodipine, Amlodipine. Preferred calcium channel antagonists include, but are not limited to, the following drugs, of which the most preferred are those that are capable of crossing the blood brain barrier, for example, nimodipine (Miles Pharmaceuticals, West Haven, Conn.) Smith Kline drug no. 9512 (Smith Kline, French Beecham, Philadelphia, Pa.), and diproteverine (Smith, Kline, French-Beecham). Less preferred antagonists are those that are less CNS permeable, for example, verapamil (Calan, G.D. Searle & Co., Chicago, Ill.; Isoptin, Knoll, Whippany, N.J.), nitrendipine, diltiazem (Cardizem, Marion, Kansas City, Mo.), and nifedipine, U.S. Pat. No. 3,485,847, hereby incorporated by reference (Procardia, L Pfizer, NY, N.Y.; Adalat, Miles). Other Ca.sup.2+ channel antagonists which may be useful are mioflazine, flunarizine, bepridil, lidoflazine, CERM-196, R 58735, R-56865, Ranolazine, Nisoldipine, Nicardipine, PN200-110, Felodipine, Amlodipine, R-(−)-202-791, and R-(+) Bay K-8644 (Miles, Bayer), whose chemical formulae are described in Boddeke et al., Trends in Pharmacologic Sciences (1989) 10:397 and Triggle et al., Trends in pharmacologic Sciences (1989) 10:370.
For patients suffering from psoriasis, over 80% will experience hyperplastic thickening of the skin called a psoriatic plaques. Current treatments to control psoriatic plaques involve treatments to suppress the immune response causing the plaques or to us keratolytic agents to soften and remove the plaques. The effectiveness of keratolytic topical agents is that they tend to be irritating not only to the areas of skin affected by the psoriatic process, but also to the healthy surrounding skin which they invariably come in contact with.
Keratolytic agents are also used to treat corns and calluses. Current treatments for corns using keratlytic or skin softening agents also tend to be irritating not only to the areas of skin affected by the psoriatic process, but also to the healthy surrounding skin which they invariably come in contact with. And shaving, abrasive methods also tend to wear through at the thinnest areas of these lesions being treated causing pain and bleeding which prevents there complete removal which helps to ensure there recurrence.
Current treatments for wart removal are surgical excision or repeated application of a toxic chemical to burn and/or dissolve/soften the skin to kill skin cells that are infected. Other methods to kill infected skin tissue involve extreme heating, for example, laser, electro-cautery and the like or extreme cooling such as by liquid nitrogen, or coolant sprays to freeze the lesion and bordering tissues. Unfortunately these methods invariably also destroy healthy skin that is continuous with these viral lesions, resulting in a large area of tissue destruction and a large painful wound that often takes weeks to heal.
Current treatments for wart removal are frequently painful and require prolonged and frequently multiple treatments while having a high rate of recurrence. Wart removal is often ineffective since the pain, discomfort and associated disability often causes patients to terminate their treatment before the virus has been cleared.
Pharmaceutical compositions comprising a calcium channel blocker, particularly verapamil, in combination with a quinoline are known to treat viral infections (U.S. Pat. No. 6,734,192 B1—Keller, Robert H., issued May 11, 2004), particularly HIV. United States Patent Application No. 20040253300, —Easterling, W. Jerry, published Dec. 16, 2004 describes a topical, transdermal medicament for use in treating existing scars comprising: a carrier host agent for facilitating non-invasive, transdermal delivery of a calcium antagonist into scar tissue; a therapeutic dosage of a calcium channel blocker agent suspended in said carrier host agent. The calcium channel blocker is preferably verapamil.
United States Patent Application No. 20050020569, —Easterling. W. Jerry, published Jan. 27, 2005 describes a medicament for use in reducing fibrosis in elastic tissues of the human male comprising: a transdermal carrier compound for facilitating non-invasive, transdermal delivery of calcium channel blocker agents to internal tissues of the human penis; a calcium channel blocker agent dispersed in said carrier means. The calcium channel blocker is preferably verapamil.
United States Patent Application No. 20060216338, —Easterling, W. Jerry, published Sep. 28, 2006 describes a medicament for use in the treatment of tissue disorders involving collagen degeneration, comprising: a carrier compound for facilitation non-invasive, transdermal delivery of calcium channel blocker agents in human recipients; and a calcium channel blocker agent dispersed in said carrier means.
United States Patent Application No. 20080139584, —Kopacki, Matthew H., published Jun. 12, 2008 describes a method for healing a wound, comprising the steps of: topically administering a wound healing composition to a wounded area, wherein the wound healing composition comprises: a first medicament characterized as a calcium channel blocker or pharmaceutically acceptable salts or solvates thereof: a second medicament characterized as a hemorrheologic agent or pharmaceutically acceptable salts or solvates thereof; and a dermal penetrating agent or pharmaceutically acceptable salts or solvates thereof.
Verapamil is a known Ca channel blocker and is a competitive inhibitor of P-glycoprotein, as described by Inoue et al. (1993); Hunter et al. (1993); Hori et al. (1993); Pourtier-Manzanedo et al. (1992); Boesch & Loor (1994); Zacherl et al. (1994); Shirai et al. (1991); Morris et al. (1991); Muller et al. (1994); and Miyamoto et al. (1992). Thalhammer et al. (1994) showed that P-glycoprotein-mediated transport of the cationic dye, acridine orange, across the bile canaliculi was inhibited by cyclosporine A and verapamil.
The ATP-15 dependent transport of amphiphilic cations across the hepatocyte canalicular membrane by p-glycoprotein was also studied by Muller et al. (1994). Transport of permanently charged amphiphilic cations was inhibited by verapamil, quinidine and daunorubicin (an antibiotic). Bear (1994) showed that verapamil, colchicine, vinblastine daunomycin and (50 microM) blocked an outwardly-rectifying chloride channel that was proposed to be associated with p-glycoprotein expression. Obi et al. (1992) used the calcium-channel blocker, verapamil, with adriamycin in chemotherapy for superficial bladder cancer.
Verapamil hydrochloride is benzeneacetonitrile α-[3-[[2-(3,4-dimethoxyphenyl)ethyl]-methylamino]propyl]-3,4-dimethoxy-α-(1-methyl-ethyl) hydrochloride; also termed CALAN™ and ISOPTIN™, and available from Searle, Knoll and Parke-Davis.
However, none of the prior art discloses the use of compositions comprising a calcium channel or a calmodulin blocker by topical application for the elimination of hyperplastic skin lesions of the dermis and epidermis, such as plantar warts, hyperplastic scarring, genital warts, cutaneous warts, skin tags.
Thus, there is still a serious need for a pharmaceutical treatment of aforesaid warts and the like.

Compositions comprising a calcium channel blocker or a calmodulin blocker  for use in the removal of hyperplastic skin lesions


A transmission with two parallel shafts has an input shaft that may be directly connected to an engine crankshaft. The input shaft carries fixed gears that are at all times meshed with corresponding gears on the output shaft. Also, the input shaft has a screw type pump to circulate and cool fluids.. The output shaft carries various modules. Each module is made up of an electromagnetic clutch with a parallel gear-plate on each side. Modules can be added or removed. All gears on the output shaft are on bearings and free to rotate.. When a rheological and/or a magnetizable fluid between the electromagnets and the adjacent gear-plate are electrically energized, the fluid between them changes phase and/or it becomes magnetized and/or solidified.. The electromagnetic force also pulls the sliding gear-plate to bond to the electromagnet. Each side of the electromagnet is energized independently to either attract or repulse the adjacent gear-plate.. When one of the various electromagnetic clutches is installed between the engine crankshaft and the transmission input shaft. Synchronization type clutch gear-plates may be installed on the output shaft. The manual gear selector transfers electrical current from a source to the various contacts on the transmitter and thereafter along the output shaft and to the desired side of the electromagnet.

In general existing manual and automatic automobile transmissions are complicated, inefficient, expensive, and heavy. At present few automatic automobile transmissions exist with seven or more gears. The present engineering designs are extremely difficult to build and disassemble.
The present art utilizes pedal friction clutches or torque converters or very complicated electromagnetic clutches for coupling the engine to the transmission shaft and very complicated oil pumps with intricate valve boxes and channels to distribute high pressure oil to control clutches so gears can be meshed or activated. Recently, computers have been incorporated to better control the timing for meshing gears in automatic transmissions, but the basic engineering designs have changed very little.

Transmission for automotive vehicles or machinery


A system and associated method for synchronizing a record with a web document. A synchronizer selects a web document that is stored in a published web document repository of a content management system. The oldest web document since the latest update is selected and checked for availability. The synchronizer locates a record that corresponds to the selected web document. The synchronizer then checks respective version of the web document and the record to determine whether the record correctly represents the web document. The synchronizer then verifies whether the selected web document is available to users to avoid synchronizing latent web document that is not available to users. The synchronizer updates the located record.

Conventional content management systems are widely deployed but may lack functionalities to support highly interactive features on Internet platforms emerging with Web 2.0 technology trend. To provide Web 2.0 services to users of web document, web sites employ separate data repositories to hold records, which have to be synchronized with corresponding web document stored in conventional content management systems. However, due to complex workflow of conventional content management system, Web 2.0 records may not be timely and efficiently synchronized with web document in a conventional content management system.
Thus, there is a need for a system and associated method that overcomes at least one of the preceding disadvantages of current methods and systems of synchronizing data repository records with web documents in a content management system.

System and method for synchronizing data record with web document in a content management system

International Business Machines Corporation


This invention relates to a method of repairing existing manholes and similar structures by applying a fast-curing elastomeric material using spray techniques whereby a homogeneous, non-porous, and monolithic coating or lining is formed. The fast-curing elastomeric material can be applied directly to existing substrates, which may comprise of concrete, brick, tile, mortar, and metal surfaces normally found in sewer manholes and catch basins, sewer and drainage pipes, parking decks, bridge piers and footings, holding ponds, bridge trusses, culverts, gratings, and the like and does not require any formwork. More preferably, the substrate surfaces are first cleaned and primed to improve the bond of elastomeric coating to the substrate. The most preferred primer is an aqueous solution of silane, preferably containing 10% to 30% silane. The elastomeric coatings provide effective surface protection against water infiltration, wear, and corrosion and can be applied in a single operation to horizontal, vertical, and overhead surfaces. The elastomeric materials are prepared by initiating the reaction of an isocyanate-terminated compound or polymer with an amine-terminated polymer or an aliphatic or aromatic diamine immediately before applying the elastomeric material to the surface to be coated. Preferably the reactive component (i.e., isocyante-containing and amine-containing materials) are mixed directly in the spray gun used to apply the elastomeric material.

This invention relates generally to a method of repairing existing manholes and similar structures using elastomeric materials. More specifically, this invention relates to a method of repairing existing manholes and similar structures by applying a fast-curing elastomeric material using spray techniques whereby a homogeneous, non-porous, and monolithic coating or lining is formed. In the most preferred embodiment, the surfaces to be coated are first cleaned and primed with a water-based primer. The fast-curing elastomeric material can be applied directly to existing concrete, brick, tile, mortar, and metal surfaces normally found in sewer manholes and catch basins, sewer and drainage pipes, parking decks, bride piers and footings, holding ponds, bride trusses, culverts, ravines, and the like and does not require any formwork. The elastomeric coatings of this invention provide effective surface protection against water infiltration, corrosion, and wear and can be applied in a single operation to horizontal, vertical, and overhead surfaces. The elastomeric materials used in the present invention are prepared by initiating the reaction of a isocyanate-terminated compound or polymer with an amine-terminated polymer or an aliphatic or aromatic diamine immediately before applying the elastomeric material to the surface to be coated. Preferably the reactive components (i.e., isocyanate-containing and amine-containing materials) are mixed directly in the spray gun used to apply the elastomeric material.
The repair and rehabilitation of the infrastructure in most of the industrialized world has become of increasing importance in recent years. The deteriorating infrastructure--including engineering structures such as sewer systems, water collection systems, brides, culverts, catch basins, and the like--is becoming an ever increasing challenge to repair and maintain in a cost effective and timely manner. Of particular importance are the sewer systems--including both the lines and access manholes--in our older cities which may have been installed a century or more ago. Due to the location of many of these systems below ground, deterioration of the infrastructure is generally not readily apparent to the public until there is acute failure resulting in cracked pavement, collapsed streets, sewer backups, local flooding, low water pressure, or other severe problems. Also due to the underground location of these structures, complete replacement of the systems is very expensive as well as disruptive of human and economic activities above ground. If a sewer system is allowed to deteriorate until acute failures occurs, often the only method available to correct the problem is total replacement of the failed portion of the system. It is preferred, therefore, to apply preventive maintenance measures to such systems to prevent, or at least minimize, such acute failures and to maintain the operating capabilities of such systems. It is desirable, therefore, to provide methods by which such engineered structures can be repaired simply, effectively, with minimal downtime, and at a low-cost.
Several methods short of total replacement have been developed for the repair or rehabilitation of existing structures such as sewer manholes. For example, U.S. Pat. No. 5,002,438 provides for the repair of existing manhole structures by the spray application of a cementitious mixture to the interior of the manhole structure to form a liner. Two to five hundred pounds of the cementitious mixture is generally required to repair a typical manhole structure. And such a liner can only be put back into service after the cement mixture sets. A booklet published by the U.S. Department of Housing and Urban Development entitled "Utility Infrastructure Rehabilitation" (November 1984) ("Booklet") also presents several methods that are reportably useful in such rehabilitation efforts. These methods include (1) coatings (such as epoxy, acrylic, or polyurethane) applied to the interior walls of the manhole, (2) chemical grouts injected into the surrounding ground from the interior of the manhole, and (3) structural liners (e.g., a fiberglass liner) inserted inside the manhole. Booklet at 5-57 to 5-58. None of these methods have proven to be completely satisfactory. For example, although it is known to apply polyurethane coatings with a airless sprayer, the surface to be coated by be very clean, free of debris, structurally sound, . . . [and] dry." Id. at 5-57. For structurally damaged or disintegrated manhole structures (i.e., the structures most in need of repair and most likely to be found in the sewer systems of our older cities), only the structural liners are reported to be useful. Id. at 5-59. Thus, additional methods are needed to repair and rehabilitate existing manholes, especially structurally damaged or disintegrated manhole structures. It would be desirable to provide a relatively simple and quick method for the repair or rehabilitation of both structurally sound manholes and structurally damaged or disintegrated manholes. It would also be desirable if such a method used a minimum of materials and if the repaired manhole could be returned to service almost immediately. It would also be desirable if such a method could be used on both the brick and mortar interior surfaces as well as on metal surfaces commonly found in manholes. The present invention provides such a method. Other advantages and benefits of the present invention will become apparent upon a review of the specification.

Method for the repair of existing manholes using elastomeric materials


A sealed lead-acid battery of the absorption-at-the-negative-electrode type employing an immobilized liquid electrolyte in which stratification of the electrolyte is eliminated. In accordance with the invention, a lower part of the positive and negative plates is supplied with water formed by a reaction or phase change of substances contained within the container of the battery. In a preferred embodiment, this is done by producing a temperature difference within the container. Also, water may be provided to the lower part of the positive and negative plates by increasing the speed of certain reactions at the lower part of the negative plate relative to the upper part thereof.

The present invention relates to an improved sealed lead-acid battery of the gas recombination type wherein a liquid electrolyte is immobilized and oxygen gas evolved at the positive plate is caused to react with the negative plate.
In a conventional sealed lead-acid battery of this type, the liquid electrolyte is immobilized either in the form of a gelled fine silica powder or in the form of a mat typically made of glass fibers, and oxygen gas evolved at the positive plate moves to the negative plate and undergoes a "sealed" reaction therewith. In such a lead-acid battery, sulfuric acid in the upper part of the electrolyte is consumed in the discharging process whereas, in the charging process, sulfuric acid is released from the plates into the electrolyte and sinks to the bottom. Therefore, as discharge-charge cycles are repeated, the electrolyte stratifies, producing an upper layer containing a low concentration of the electrolyte and a lower layer containing a high concentration of the electrolyte.
In ordinary flooded lead-acid batteries using a free flowing electrolyte, stratification of the electrolyte can be readily recovered by agitation such as by gassing when in the overcharged condition or by pumping a gas into the electrolyte. On the other hand, in the sealed lead-acid battery of the type contemplated by the present invention wherein the electrolyte is immobilized, only a small degree of electrolyte stratification occurs during discharge and charge reactions, and such stratification proceeds very slowly. Additionally, due to the effects of gravity, more of the electrolyte is present at the lower part of the electrode plates or separator than at the upper part, with the result that the sealed reaction has a tendency to occur at the upper part of the negative plate more easily than at the lower part. As will be described below in more detail, however, water is formed as a result of the sealed reaction, and this makes it very difficult to avoid the occurrence of electrolyte stratification. Moreover, since the immobilized electrolyte in the sealed lead-acid battery is difficult to agitate, it is practically impossible to eliminate stratification of the electrolyte, resulting in an unavoidable capacity drop and sulfation in the lower part of the electrode plates.


An exhaust gas purification device for an internal combustion engine comprises, an exhaust passage including a catalyst for conveying exhaust gas discharged from the engine to the outside, and a bend formed by bending a portion of the exhaust passage directly upstream of the catalyst, the bend causing exhaust gas discharged from the engine to collide against a corner portion between an inlet end face of the catalyst and such portion of a wall of the exhaust passage that follows the outside of the bend, thereby increasing pressure at the corner portion, compared with the other portion of the inlet end face, and an additive injection valve fitted to the outside of the bend of the exhaust passage to inject an additive in such manner that the injected additive passes just above the corner portion and falls on the inlet end face of the catalytic converter.

1. Field of the Invention
This invention relates to an exhaust gas purification device for an internal combustion engine, configured to inject an additive to be supplied to a catalyst.
2. Description of the Related Art
In order to purify exhaust gas of diesel engine automobiles (vehicles), an exhaust gas purification device using an NOx trap catalyst, an NOx selective reduction catalyst, a particulate filter (diesel particulate filter) and/or the like in combination is used to prevent NOx (nitrogen oxides) and PM (particulate matter) in exhaust gas of the diesel engine from being emitted into the atmosphere.
For such exhaust gas purification devices, increasingly being adopted is a configuration in which a catalyst called a pre-stage catalyst, such as an oxidation catalyst or an NOx reduction catalyst (NOx trap catalyst or NOx selective reduction catalyst), is disposed in an exhaust passage for conveying exhaust gas discharged from the engine to the outside, and a fuel addition valve (reducing-agent addition valve) for injecting fuel as an additive required for reaction promoted by the catalyst is disposed upstream of the catalyst, for example, the oxidation catalyst.
In such exhaust gas purification devices, in order to enhance the purification efficiency in the cold state of the engine, the pre-stage catalyst is disposed near the exhaust side of the engine.
The space in the engine room is, however, limited. Thus, as shown in a patent gazette (Japanese Patent Laid Open No. 2005-127260), for example, there is a tendency to use an exhaust passage including a bend, for example an L-shaped bend to allow a pre-stage catalyst to be disposed directly downstream of the bend, and inject fuel from the outside of the bend toward an inlet end face of the catalyst, disposed directly downstream of the bend.
In this configuration, however, the flow of fuel injected from the outside of the bend toward the catalyst merges into exhaust gas passing through the bend, therefore curving, so that the fuel flow is liable to be constantly pushed from the inside to the outside of the bend by the exhaust gas passing through the bend.
Thus, in high-load operation of the engine with an increased flow volume and velocity of exhaust gas, the exhaust gas pushes the injected fuel flow from the inside of the bend with an increased force, so that the fuel flow deviates from a predetermined position on the inlet end face of the catalyst, for example from the center toward the side of the catalyst corresponding to the outside of the bend. In low-load operation of the engine with a decreased flow volume and velocity of exhaust gas, in contrast, the exhaust gas pushes the injected fuel flow with a decreased force, so that the fuel flow deviates toward the opposite side of the catalyst. Such deviation of the fuel flow directly reflects the operating state of the engine and is liable to become excessively great.
This leads to the problem that the fuel required for reaction fails to be supplied to the pre-stage catalyst in a desired direction, so that the catalytic converter using the pre-stage catalyst fails to show satisfactory performance.

Exhaust gas purification device for internal combustion engine

Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Mitsubishi Jidosha Engineering Kabushiki Kaisha


A pipe coupling structure is capable of coupling pipes together without driving a screw and using a tool. An example pipe coupling structure includes a first engagement portion formed in an end portion of a first air-conditioning duct. The first engagement portion extends in the circumferential directions and protrudes inside of the first air-conditioning duct. A second engagement portion is formed in an end portion of a second air-conditioning duct. The second engagement portion extends in the circumferential directions and protrudes outside of the second air-conditioning duct. When the end portion of the second air-conditioning duct is inserted into the end portion of the first air-conditioning duct, the second engagement portion climbs over the first engagement portion, and thereby the first engagement portion and the second engagement portion engage each other.

For example, in connecting two air-conditioning ducts, conventionally, an end part of a cylindrical bayonet joint (nipple) is inserted into an end part of the one duct, and the other end part of the bayonet joint is inserted into an end part of the other duct. Then, both insertion parts are subjected to screw driving or the like using an electric power tool. However, in this method, a bayonet joint is indispensable separately in addition to ducts, thereby increasing the cost of component parts. Further, screw driving or the like needs to be given to the two insertion parts, thereby taking time and cost for the work.
Therefore, a spiral pipe is known which has an end part smaller in outer diameter than the pipe itself, thereby dispensing with a bayonet joint (e.g., refer to Patent Document 1). This spiral pipe is formed by shrinking the outer diameter of an end part thereof, making a plurality of grooved concave portions in the shrunk part (the diameter-shrunk end part) and inserting the shrunk part into a spiral pipe to be connected thereto. Consequently, a bayonet joint becomes dispensable.


A coffee machine has an assembly provided with a chamber for receiving a permanent filter selected, according to the taste preference of a user, from a set of such filters which each offer different flow resistance to water per unit time. A pod of ground compressed coffee is also removably receivable in the chamber; the characteristics of pod and filter are so selected that during each operation of the machine between 22-26% of the total aromatic substances present in the coffee in the pod, are extracted by hot water flowing through the pod. However, due to the different flow resistance offered by different filters, the quantity of beverage produced during a predetermined operating time will vary. In dependence upon the particular selected filter, the extracted aromatic substances will therefore be more or less diluted in the beverage, to suit a particular taste.

1. Field of the Invention
This invention relates to an improved coffee machine and coffee-brewing system.
More particularly, the invention relates to an improved coffee machine and coffee-brewing system utilizing pods of compressed ground coffee.
Still more specifically, the invention relates to a coffee machine and coffee brewing system wherein the cooperation of special structural features of the machine with prescribed characteristics of the respective coffee pods results in a coffee beverage of unvarying quality.
2. The Prior Art
Coffee machines are known in a wide variety of types and work according to various operating principles. The present invention is concerned with machines wherein hot water is caused to pass through ground coffee, and in particular the type wherein the water passes through a water-permeable pod of ground coffee (tea-bag like, but compacted under pressure).
Coffee machines of the type using such pods (hereinafter called "pod" for simplicity) are known from e.g. U.S. Pat. Nos. 3,327,613 and 3,370,523. What is not known from the prior art is a machine wherein the characteristics of the coffee extracting chamber housing the pod during brewing (hereinafter called "the extracting chamber") are coordinated with specified characteristics of the pods themselves and of the coffee filter through which the beverage must pass.
The only relationship between these aspects, which is known from the prior art, is an empirical one. As a direct consequence of this the coffee beverage brewed with the prior-art machines,--even though their mechanical operation be satisfactory--will vary in taste and wholesomeness from brewing to brewing. In other words: the brewing results are not reliably reproducible and therefore not satisfactory.


An industrial furnace and a burner for regenerative combustion includes a heat storage member, a switching mechanism disposed on one end of the heat storage member, and a burner tile disposed on the opposite end of the heat storage member. The burner tile has a protruding portion extending ahead an air supply and gas exhaust surface. The switching mechanism has a stationary disk and a rotatable disk which slidably contacts the stationary disk. A speed of supply air to the furnace is in operation equal to or higher than a speed of exhaust air therefrom.

1. Field of the Invention
The present invention relates to an industrial furnace, a burner thereof and a combustion method therefor for conducting regenerative combustion. In regenerative combustion, heat from exhaust gas is stored in a heat storage member by causing exhaust gas to flow through the heat storage member. Gas flow through the heat storage member is then alternately switched between supply air flow and exhaust gas flow, whereby supply air flowing through the heat storage member, in which the heat from the exhaust gas is stored, is heated by the heat storage member.
2. Description of Related Art
Japanese Patent Publication No. HEI 5-246423 discloses a pair of burners for conducting regenerative combustion which are alternately switched in operation. A heat storage member is mounted in a main body of each burner, and a switching valve is disposed outside the main body of each burner in communication with the main body of each burner.
As a result, the burner has a problem that piping for connecting the switching valve and the main body of the burner needs to be provided. This makes the combustion apparatus large. Therefore, a long purging time period at every switching time results because the volume in the piping to be purged is large.
To address such problems, one of the applicants of the present application proposed a burner for conducting regenerative combustion wherein a switching mechanism is mounted within a main body of the burner. In the burner, a heat storage member is sectioned into a plurality of circumferential sections by partitioning plates extending in an axial direction of the burner. A rotatable disk slidably contacts end surfaces of the partitioning plates so that supply air flow and exhaust gas flow through the sections of the heat storage member are switched in accordance with rotation of the rotatable disk.
Further, with the proposed burner, as well as the burner of Japanese Patent Publication No. HEI 5-256423, a fuel release surface and an air supply and gas exhaust surface, where a plurality gas flow holes for causing supply air and exhaust gas to pass therethrough are open, are positioned in the same plane perpendicular to an axis of the burner.
However, the proposed burner and the burner of HEI 5-256423 still have the following problems:
First, because the same gas flow hole is used as a supply air flow hole and as an exhaust gas flow hole by switching a gas flow between supply and exhaust, a cross-sectional area for allowing supply air to pass therethrough and a cross-sectional area for allowing exhaust gas to pass therethrough are equal with each other. As a result, it is difficult to raise a supply air flow speed by throttling the cross-sectional area of the supply air flow hole, because if throttled, the cross-sectional area of the exhaust gas flow hole is necessarily also throttled, which raises the internal pressure of the furnace to an intolerable level. Thus, the supply air flow speed cannot be raised. As a result, the amount of burnt gas drawn and involved by the supply air flow and recirculated in the furnace is small, making it difficult to suppress generation of NOx. Further, the amount of fuel drawn by the supply air flow is also small, which degrades combustion and shortens the length of a combustion zone in a direction from the burner toward an opposite end of the furnace.
Second, supply air is likely to leak through a clearance between the end surfaces of the partitioning plates and the rotatable disk, shortening the path to the exhaust gas. As a result, the supply air flow speed is further decreased, which strengthens the above problems. Further, the shortened path will cause a deficit in available supply air, thereby causing imperfect combustion and increasing CO in the exhaust gas.
Third, when combustion is conducted using the conventional burner having the fuel release surface and the air supply and gas exhaust surface in the same plane, amount of CO (carbon monoxide) and NOx (nitrogen oxides) in the exhaust gas is large, so that some treatment for decreasing the amount of CO and NOx is often needed. Further, the combustion zone produced by the conventional burner is usually short.

Industrial furnace and a burner for conducting regenerative combustion and a combustion method therefor


This invention is a method and system for improved garbage collection in a distributed computing system. Garbage collection is the process of releasing resources that are no longer being utilized by the objects to which those resources are allocated. Specifically, a garbage collection system and method are described that allow for different types of garbage collection to be used at different times and/or on different objects or resources in the system. In the preferred embodiment, the garbage collection routines are contained in separate mobile code module that can be changed dynamically interchanged to provide different garbage collection algorithms.

This invention generally pertains to managing the allocation and reclamation of computer resources, including computer memory, which is generally know as "garbage collection." In particular, the invention is related to garbage collection in distributed computing systems. Therefore, some background regarding distributed computing systems and techniques is first provided, followed by a description of the background for garbage collection.
Distributed Computing Systems
A distributed system is a collection of autonomous computing entities, hardware or software, connected by a communication medium. While often the computing entities are geographically dispersed, in some instances they might be separate processors in a multi-processor computer or even separate software routines executing in logically isolated memory space on the same computer. A computing entity need not be a traditional computer, but more generally can be any computing device, ranging from a large mainframe to a refrigerator or a cell phone. A distributed application is an application that executes on a distributed system and one in which parts of the application execute on distinct autonomous computing entities.
Whenever a distinct component of a distributed application requests something (e.g., a data value, a computation) of another component, the former is called a client and the latter is called a service. It is worth noting that the terms service and client are not exclusionary in that an item can be both a client and a service. For example, a routine that calculates the time between two events may be a client and of a clock service; if the clock service then calls a routine that converts to Daylight Savings Time, the clock becomes a client and the Daylight Savings Time converter is its service.
Mobile code generally refers to a computer program that can be written on one platform and executed on numerous others, irrespective of differences in hardware, operating system, File system, and many other details of the execution environment. In addition to independence from the physical characteristics of the execution environment, a mobile program may move from one computer to another in the middle of its execution.
Mobile code may be pre-compiled, or compiled when it arrives at the execution platform In the first case, numerous versions of the program must be written and compiled, then matched across run-time environments; this is mobile code in the letter, but not the spirit, of the definition. In addition, the same pre-compiled program cannot move from one platform to a different one during its execution. In the second, the program text may be distributed along with configuration scripts describing what to do in each execution environment. This distributes and delays the specificity of the pre-compiled option. The more interesting, and far more common approach exploits a standard virtual machine, which finesses all the issues of platform heterogeneity. The virtual machine is a program that itself mitigates the machine dependencies and idiosyncrasies, taking the raw program text and compiling it to a binary executable.
FIG. 1 shows a typical distributed application of the existing art. There are two clients 2, 4 and four services 10, 12, 14, 16 that the clients 2, 4 might need. Each service has a service proxy 10a, 12a, 14a, 16a which is a module of mobile code that can be used by clients to invoke that service. A service proxy 10a, 12a, 14a, 16a contains the code needed by a client 2, 4 to interact with a service. For instance if a service is a digital camera on a robotic arm, the interfaces might include Initialize( ), Zoom( ), Rotate( ) and Get_Picture( ). The service proxy 10a, 12a, 14a, 16a may also provide the expected return values for the service, which might include error codes as well.
In addition to clients 2, 4 and services 10, 12, 14, 16 distributed applications need some mechanism for clients to find services. Often such knowledge is assumed a priori, but many distributed applications use a look-up service. The look-up service 20 is a service with which the other services are registered or advertised to be available for use by clients. In a simple system, where there is no attempt to coordinate replicas of services, each new service registers with the look-up service 20 (in the case of replicas, the onus falls on the client to resolve conflicts and ambiguity). When a services 10, 12, 14, 16 registers, it provides information telling clients 2, 4 how to find it. Commonly, this is a physical location such as an IP address and port number, but in the most modern systems this can be as powerful as giving the look-up service 20 a service proxy 10a, 12a, 14a, 16a, which is mobile code that clients 2, 4 execute and use to invoke the services 10, 12, 14, 16. In this way, the service proxy 10a, 12a, 14a, 16a contains not only location information but instructions for how to use the services 10, 12, 14, 16. While just as necessary for the client 2, 4 as location information, this has generally been assumed as a priori knowledge. When a client 2, 4 wishes to work with a service 10, 12, 14, 16 it locates it through the look-up service 20, downloads the service proxy 10a, 12a, 14a, 16a for that service 10, 12, 14, 16 from the look-up service 20, then uses the service proxy 10a, 12a, 14a, 16a to invoke the service 10, 12, 14, 16. The look-up service 20 may also have attributes of the services 10, 12, 14, 16, such as whether it is a grouped service, what type of group it is, what its cost to use is, how accurate it is, how reliable it is, or how long it takes to execute. In such cases the clients 2, 4 can use the attributes to decide which of a number of services 10, 12, 14, 16 it wishes to use.
Each of the foregoing has access to a communication network 22 so that it is capable of communicating with at least some of the other members in the distributed computing application. The communication network 22 may be wireless, a local area network, an internal computer bus, a wide area network such as the Internet, a corporate intranet or extranet, a virtual private network, any other communication medium or any combination of the foregoing.
In the prior art example shown in FIG. 1, one client 2 is a roadway traffic monitoring program that notifies a user when and where traffic has occurred and the other client 4 is an automated toll collection program. The services are a clock 10, a road sensor 12 that monitors traffic flow on a highway, a toll booth sensor 14 that detects an ID device in each car that passes through the toll, and a credit card charge program 16. When each service 10, 12, 14, 16 becomes available to the application it registers with the look-up service 20 and provides the look-up service with its service proxy 10a, 12a, 14a, 16a.
When the traffic monitoring client 2 begins, it queries the look-up service to see if a clock is available and what sensors are available. The look-up service 20 responds by providing the client 2 with the clock proxy 10a, the road sensor proxy 12a and the toll booth sensor proxy 14a. The traffic monitoring client 2 uses the service proxies 10a, 12a, 14a to invoke the clock 10 and the sensors 12, 14, and then to monitor traffic at various times of the day.
Similarly when the toll collector client 4 begins, it queries the look-up service 20 to see if a toll booth sensor 14 and a credit card charge service 16 are available. The look-up service 20 responds by providing this client 4 with the toll booth sensor proxy 14a and the credit card charge proxy 16a. The toll collector client 4 uses the service proxies 14a, 16a, to invoke the toll booth sensor 14 and the credit card charge program 16, and then to identify cars that pass through the toll booth and charge their credit cards for the toll.
A known technique in the existing art is leasing. A lease is an important concept throughout distributed computing, generally used between a client and service as a way for the service to indicate its availability to the client for a length of time. At the end of the lease, if the lease is not renewed, there is no guarantee of availability. In a simple example, a service may register with a look-up service and be granted a lease for five minutes. This means that the lookup service will make itself available to the service (i.e., list it) for five minutes. If a camera grants a lease to a client for two minutes, then that client will be able to position, zoom, and take pictures for two minutes. There are a wide variety of ways to handle lease negotiation, renewal and termination which are well known to those skilled in the art of distributed computing and all such methods are meant to be incorporated within the scope of the disclosed invention. A detailed explanation of leases can be found in, Jim Waldo, The Jini Specification, 2nd Edition, chapter LE (2001), which is incorporated herein by reference.
One useful aspect of leases is that they can be used for simple failure detection. If the expectation is that a client will continue to request lease renewal from a service, but then does not renew its lease, the service may assume that the client has failed, or is otherwise unavailable This allows the service to more efficiently manage its own resources, by releasing any that were dedicated to expired clients.
This is especially important because components only rarely plan and announce their failure and are not able to predict network outages. It is far more common that failures and outages are unexpected, and that the consequence is an inability to announce anything. In these cases, a client will not renew its lease so that eventually, the granting service will reallocate its resources. The shorter the lease period, the sooner a failure can be detected. The tradeoff is that both client and service spend proportionately more time and resources dealing with leasing.
Jini is one example of a commercially available specification for a distributed object infrastructure (or middleware) for more easily writing, executing and managing object-oriented distributed applications. Jini was developed by Sun Microsystems and is based on the Java programming language; consequently, objects in a Jini system are mobile. Jini is described in Jim Waldo, The Jini Specification, 2nd Edition (2001). The Common Object Request Broker Architecture (CORBA), developed by the Object Management Group, and Distributed Component Object Module (DCOM), developed Microsoft Corporation, are two other commercially available examples that are well known in the prior art. Jini, DCOM, CORBA and a number of other distributed computing specifications are described by Benchiao Jai et al., Effortless Software Interoperability with Jini Connection Technology, Bell Labs Technical Journal, April-June 2000, pp. 88-101, which is hereby incorporated by reference.
Garbage Collection
In modern computer systems, regardless of whether they are distributed or centralized, resources are allocated to an object when it is instantiated, and in some cases later during the object's existence if the object requests additional resources. Typically the resource is computer memory, but it may also include other needed system resources such as disk space, processing power or communication bandwidth. In many instances, once the resources are allocated to an object no other object can use this resource until the first object releases (or does not renew) the resource, regardless of whether or not the first object is actually using the resource. For example, if a particular block of memory is allocated for an object to execute in, no other object can use this memory space. In other circumstances, multiple objects may use a single resource, but there may be a limit to the amount of that resource available. For instance, a communication channel with 20 Mb of bandwidth may guarantee 8 Mb of bandwidth to two different objects, but when a third object requests another 8 Mb, the request should be denied.
In the ideal world, each object would release resources either when it finishes execution or when it will not be needing a particular resource for an extended period of time. Unfortunately, many objects are not "well behaved" and fail to appropriately release resources. Even well behaved programs sometimes crash or hang before they can release their resources. This is why leasing, described above as a failure detection mechanism, can be used as the trigger for garbage collection to begin. This problem is further complicated in distributed applications where the communication channel between an object and a resource may be interrupted, thereby preventing the object from releasing the resource, or causing the resource to believe the object has crashed.
Resource allocation is the process by which portions of resources are reserved for objects in a computer system to use. Garbage collection is the process by which these reserved resources are "freed up", or deallocated so that other objects can use them.
The problem of unused resources not being freed is familiar even to many casual personal computer users. Many times a personal computer will indicate that it has low or insufficient memory, even though the user has no software other than the operating system running. The common way to solve this problem is to reboot the computer, which frees all resources from all objects and restarts the computer from a pure state. This (not very optimal) way of performing garbage collection penalizes all objects rather than just those responsible for hogging memory.
One problem inherent is garbage collection is that a resource may be released when the object is still expecting it to be there. At best this will cause the object to have to reacquire the needed resource, but it may also cause a less robust object to report an error or to crash. For example, a straightforward garbage collector may be programmed to free any resource that has not been used for more than sixty seconds. Now consider that an object may not be able to call a resource for longer than that time because its communication link is down, but that the object is still invoking and queuing calls to the resource. When the communication link is re-established, the object will send the calls to a resource that is no longer available to it, causing the object to fail, or perhaps even causing conflicts and incorrect behavior for the resource. On the other hand, if the garbage collector waits for five minute of inactivity to free up the resource, that resource may go underutilized causing other objects to delay or block because they cannot access that resource. Thus tension exists between the "aggressiveness" of the garbage collector, and the goal of ensuring that objects have the resources they expect. Garbage collection for a scarce resource may be more aggressive, while it would be less aggressive where reliability is of greater concern. Different garbage collection algorithms are optimized for different types of applications, and may be further tuned to make them more or less aggressive. For instance, in the simple algorithm described above, the lapse time could be varied to make the garbage collector more or less aggressive.
One means of garbage collection is reference counting. Each object has a reference, or a pointer, to each resource that it uses. The garbage collection routine can monitor the number of references to each resource and free up the resource when there are no longer any references. This method tends to work best in localized (non-distributed) applications where a single operating system can monitor the references. It is difficult for a remote routine to monitor references on another computer accurately and in a timely manner; specifically, a communication lapse may cause the garbage collector to believe the reference is gone.
Leasing, a technique describe above, is an effective method of garbage collection. When the lease ends the resource is released, unless the lease has been renewed. Such a use of leasing is described in U.S. Pat. No. 5,832,529 to Wollrath et al., entitled "Methods, Apparatus, and Product for Distributed Garbage Collection."
Another known technique for garbage collection is for the garbage collector or a resource to "ping" the object (or objects) using a resource at fixed intervals. A response to the ping from the object indicates that the object is operating—it has not crashed or hung and the network connection to it is viable. One problem with this method is the amount of non-useful communication injected in the network; another problem is that it requires reliable two-way communication in order to maintain the object's liveness.
Another known technique for garbage collection is last reference time stamp. In this technique, a period of time is allocated to each object that uses a resource. If the object does not use that resource (e.g., no calls are received by the resource from that object) within the time period, the resource is released from that object.
One problem with the current forms of garbage collection is that they use a constant algorithm. However at different times, or under different ambient conditions, or even (in the case of shared resources) for different requesting objects, different types of algorithms may be appropriate. During periods of high contention for a resource, an aggressive algorithm might be desirable. When the system is having network communication problems, a less aggressive algorithm might be desirable. When a resource is highly shared (i.e., has many concurrent users) leasing may be preferable, whereas when it is lightly shared reference counting, while globally less efficient, would be acceptable with the accompanying benefits of improved accuracy. Current garbage collection systems do not allow for such variation.
Another restriction is that garbage collection is currently conducted by a specific garbage collection system which examines each resource according to the previously described algorithms, and decides whether or not to recall them. Resources do not garbage collect themselves when they detect they are no longer needed.
It is therefore an object of the present invention to provide a method of garbage collection that can dynamically switch between different garbage collection algorithms.
It is a further object of the present invention to provide a method of garbage collection in which the parameters of a given algorithm can be dynamically modified.
It is a further object of the present invention to provide a method of garbage collection wherein the garbage collection algorithms are written as separate mobile code objects.
It is a further object of the present invention to provide a method of garbage collection wherein resources can garbage collect themselves according to various and numerous criteria.

Method and system for multimode garbage collection


A catch basin for collecting hazardous materials in a drain comprises a container having a drain hole, an annular flange extending from the upper edge of the container for supporting the container in a drain, a cover member having a plurality of through-holes and a drain plug which is threadably inserted in a drain hole provided therefore in the bottom of the container for use in plugging the container to contain hazardous materials.

1. Field of the Invention
The present invention relates to apparatus for handling hazardous materials in general and in particular to a catch basin with a removable drain plug designed for placement in a storm drain or other type of drain for catching accidental spills of hazardous materials.
2. Description of the Related Art
Among the most serious problems associated with the handling of hazardous materials is the accidental discharge of such materials into a drain which leads to a sewage treatment plant which is not equipped to handle such materials or into a storm drain which ultimately flows into a creek, river, lake, bay, or the like. In either case, the cost of containing and cleaning up the material can be enormous both financially and in terms of the negative impact on the environment.
The manufacture of semiconductor products, for example, involves the use of hazardous materials which are usually stored in exterior tanks outside the walls of the manufacturing facility. Not infrequently, storm drains and the like which are used to collect rain water are found in the vicinity of the exterior storage tanks.
The material in the tanks is periodically replenished from a tanker truck or the like. If through negligence or by accident the material is spilled on the ground during the filling of the tanks, it could be collected by a nearby storm drain, resulting in the above-described adverse consequences.
Presently, companies seek to prevent the loss of hazardous materials in a storm drain by covering the drain with an absorbent blanket, such as a Spill Mat made by Lab Safety Supply of Janesville, Wis., or by surrounding the drain with piles of absorbent material, such as Safe-T-Sorb, available from Orchard Supply Hardware, Sunnyvale, Calif., either before an accidental spill as a preventive measure or afterwards to minimize the damage caused by the spill. Sometimes the edges of the blanket are required to be held down by some sort of heavy object such as, for example, bags of absorbent material.
When the spilled material is a liquid, the use of a bag of absorbent material, or the like, to prevent the liquid material from flowing beneath the edges of the blanket is not always successful. Furthermore, the absorbent blankets which are currently being used for this purpose are expensive and must be replaced as soon as they have become saturated with any liquid, including ordinary rainwater, because, after they are saturated, they no longer will hold any additional liquid. Also the need to hold down the edges with heavy objects is time consuming and labor intensive. Moreover, when not used to cover a drain, the blanket is usually stored in a pile immediately adjacent to the drain and is therefore unsightly. Alternatively, if the drain is in a traffic area and the blanket poses an obstacle to traffic, the blanket must be stored some distance from the drain and is therefore more likely not to be immediately available for use in case of a spill.
When loose material is used to absorb a spill, the material must be cleaned up after a spill or even after a rain. In the interim, the area is unsightly and loose particles of the absorbent material can wash down the drain.


The present invention is directed to a novel, low-toxicity and environmentally-friendly violet smoke generating composition. The composition comprises a mixture of at least one red dye and at least one blue dye, a coolant, an oxidizer, a binder, and a non-sulfur particulate fuel that is also a burn-control agent having two different particle size distributions. Preferably the fuel comprises a mixture of granulated sucrose and sucrose 10×.

Smoke generating compositions which are used by the military to produce violet smoke typically comprise a formulation which includes sulfur as a fuel, potassium chlorate as an oxidizer, a violet dye, and a binder for maintaining the smoke generating formulation, typically in the form of a mixture in a compact form so that it may be used in the production of, for example, smoke generating grenades.
The requirements for an effective colored-smoke composition are set forth below and include the following.
The composition must produce sufficient heat to vaporize the dye, as well as produce a sufficient volume of gas to disperse the vaporized dye into the surrounding environment.
The composition must also ignite at a low temperature and continue to burn smoothly at a low temperature (well below 1000° C.). If the temperature is too high, the dye molecules will decompose, and the generated smoke's color quality and volume will deteriorate. The use of metal fuels should be avoided in colored smoke generating compositions because of the high reaction temperatures they may produce.
Although a low ignition temperature is required, the smoke-generating composition must be stable during manufacturing and storage over the expected range of ambient temperatures.
The molecules creating the colored smoke must be of low toxicity (including low carcinogenicity). Further, they must readily sublime without decomposition at the temperature of the pyrotechnic reaction to yield a dense smoke of good color quality.
In various contexts, it is desirable to have the capability to produce smoke suitable for a wide variety of applications. For example, the ability to produce smoke at a particular location may provide the basis for a remote signaling system. Such a system may have application in search and rescue operations and in military exercises. Smoke of a particular color and density may also be desirable for training purposes. For example, in order to train firefighters, it would be advantageous to simulate specific types of smoke produced by various fire conditions. For individuals working in a fire-prone environment, such as on an aircraft or ship, it would also be desirable to have the capability of simulating smoke produced by a fire in order to provide a realistic fire drill.
Smoke can be used as a marker for various purposes. A smoke marker can be seen from substantial distances, both from the ground and from the air. Accordingly, a smoke marker would be useful in military operations, search and rescue, certain types of industrial projects, or in any other situation in which it is important to find and mark a particular location.
In a military context, the need for smoke-producing devices and compositions is well appreciated. Not only can smoke be used as a marker for search and rescue, but smoke may also be used to mark a particular target. It can also be used as a marker to determine the position of specific personnel and equipment.
Particularly important for the military, smoke can also be used for screening purposes to obscure vision and detection/identification. A smoke shield can be very helpful in conducting military operations in order to prevent adverse forces from obtaining a clear view of the operations. For example, it may be desirable to use a vision obscuring smoke in order to move troops and equipment under at least partial cover.
Various types of smoke-producing compositions and devices are presently known. It is known how to judiciously select the components of a smoke-producing composition that uses a sublimable organic coloring medium. By considering the kinetics of combustion and the desired yield of colored smoke, conventional smoke-producing compositions require a strongly exothermic composition but struggle to limit the degradation of the coloring medium by combustion. A weakly exothermic composition is unsuitable because it permits only a minimal percentage of coloring medium and furnishes only a very mediocre smoke yield that is hardly visible, especially when there is a cloudy or dark sky. A weakly exothermic composition also is difficult to ignite to initiate smoke emission.
It is also known that it is advantageous to adjust the combustion speed, because a rapid combustion provokes the destruction of the coloring medium or liberates the smoke too briefly or in a non-workable manner. In contrast, a slow combustion produces a smoke yield of minimal consequence and tends toward self-extinction of the combustion process. It is known to consider the effects of the reaction thermodynamics by making an appropriate choice of the components of the composition and by the conditions of compression of the composition.
However, most existing smoke-producing compositions have severe limitations. One of the limitations is that of toxicity. Many smoke-producing compositions incorporate materials that are severely toxic or become irritants when subjected to the heat necessary to produce smoke.
A variety of dyes have been used in colored smoke mixtures. Many of these dyes are presently under investigation for carcinogenicity and other potential health hazards.
The materials that work best in colored smokes have several properties in common and include the following.
Volatility: The dye must undergo a phase change to the gas state upon heating, without also undergoing substantial decomposition. Only low molecular weight dyes (less than 400 grams/mole) are usually used because volatility typically decreases as molecular weight increases. Salts do not work well: ionic species generally have low volatility because of their strong inter-ionic attractions within the crystalline lattice. Therefore, functional groups such as —COO— (carboxylate ion) and —NR3+(a substituted ammonium salt) should be avoided.
Chemical stability: Oxygen-rich functional groups (—NO2; —SO3H) should be avoided. At the typical reaction temperatures of smoke compositions, these groups are likely to release their oxygen, leading to oxidative decomposition of the dye molecules. Groups such as —NH2 and —NHR (amines) are used, but potentially dangerous oxidative coupling reactions can occur in an oxygen rich environment.
Typically dyes for military markers and grenades are polycyclic or aromatic amino, hydroxyl, azo and keto compounds, in which unsaturation conjugated with the aromatic structure. Such compounds are known to cause chromosome mutations, which may lead to cancer. Coloring agents for new munitions are chosen to minimize potential carcinogenicity, which increases their cost, but allows recycling of the dyes without high health risks.
The current M18 violet smoke formulation uses potassium chlorate, sulfur and a violet dye to generate a violet smoke signal. While effective, the products generated are not environmentally friendly and toxicity testing on the violet dye has shown it to be more toxic compared to other dyes. Furthermore, upon reaction the sulfur in the formulation creates sulfur dioxide products which have known toxic characteristics detrimental to the environment. The sulfur also creates a safety issue during production, due to friction and impact sensitivity when intimately mixed with potassium chlorate.
Prior art colored smoke formulations have employed the use of mixtures containing a fuel, an oxidizer, and a dye. The principle behind the use of such formulations lies in the reaction between the fuel and oxidizer, and the accompanying release of a large amount of energy during the reaction. The exothermic reaction releases the energy contained in the bonds of the highly structured fuel molecule as heat. This causes the dye component of the formulation to undergo a series of phase transitions from a solid to a liquid and ultimately to a gas. However, if the temperature of the fuel-oxidizer reaction is too high, the dye will degrade, and the quantity and color quality of smoke generated will be unsatisfactory.
Conventionally, the dye exists as a solid crystal at standard temperature and pressure. When heat generated by a fuel-oxidizer reaction is applied to the solid crystal, dislocations of the molecules occur within the crystalline lattice. As molecules of the dye become detached from the central lattice, a liquid is formed. As more heat energy is applied, the individual molecules of the dye begin to move more rapidly, and this molecular activity is responsible for the transition of the dye molecules from the liquid phase to the gas phase.
Although heat is required for the dye to undergo the essential phase changes to produce colored smoke, individual molecules of the dye are subject to degradation at elevated temperatures. If the molecular structure of the dye is subject to forces and energies that are great enough to cleave the molecule's bonds, changes in smoke color or loss of color properties are likely to occur.
Other known compositions have the drawback of burning at temperatures that are too high (600 to 800° C.) or leave too many carbonaceous residues, which are impermeable to the dye molecules in the gas phase. These conditions cause the destruction of the smoke-producing components and therefore demonstrate poor effectiveness in producing colored smokes. Another drawback may be the rapid ascent of the smoke because of the smoke's high temperature, which causes the smoke to dissipate too quickly for the desired effect to be achieved.
Various smoke generating compositions have been made in the past. US 2015/0329437 to Hultman discloses a pyrotechnic composition including a fuel, an oxidizer, flow rate control agents and oleoresin capsicum as an irritant. The composition is useful in crowd control products. The composition comprising approximately 13% to 24% potassium chlorate, 3% to 22% baker's sugar, 6% to 22% magnesium carbonate, 20% to 40% terephthalic acid, 2% to 28% dye, 1% to 25% magnesium stearate as the rate controlling agent, and 20% to 35% nitrocellulose as the binding agent. However, the dye composition is not addressed, and it is uncertain that such composition would meet the M18 smoke grenade standards or be less toxic.
GB 1139761 to Cross discloses a riot-controlled composition comprising 40% of o-chloro benzal malonitrile, 27% potassium chloride, 18% of sugar, 12% of magnesium carbonate, and 3% of cellulose nitrate. Similar to Hultman, the dye ingredient is not addressed, and it is unlikely that such composition would have a controlled burn or meet the M18 grenade standard.
RU2369590 to Sergiveech, et al. discloses a pyrotechnic composition for color smoke containing potassium chlorate as an oxidizer, thiourea as fuel—gasifier, dicyandiamide, fluorine rubber SKF-32, lamellar graphite of Piv grade as organic dye-monomethyl aminoanthraquinone, red C fat-soluble dye, fat-soluble violet anthraquinone or hexachlorobenzene dye.
U.S. Pat. No. 6,558,487 to Tadros, et al. discloses a smoke generating composition including at least one smoke generating material and an effective amount of a polymerized monosaccharide or disaccharide both as a binder and a fuel. In the preparation of colored smoke generating compositions, potassium chlorate, magnesium carbonate and sucrose are typically combined with a dye such as solvent yellow 33 (for the production of yellow smoke) and solvent yellow 33 combined with solvent green 3 (for the production of green smoke). Further, from about 12 to 100% of the sucrose is polymerized, formed into a solution and then sprayed over the remaining components to bind the components together into a smoke generating composition. U.S. Pat. No. 6,558,487 does not address the issue of controlled burn, or toxicity associated with the dye.
US 2014/0238258 to Stoenescu discloses a colored pyrotechnic smoke-producing composition having an oxidizer, a sugar fuel, a flame retardant, a dye, a coolant, and a binder. The flame retardant may be one or more nitrogen-rich compounds. The composition may be in pelletized form, or in the US form of a solid charge. Similar to other prior art, US 2014/0238258 also does not address the issue of controlled burn, color strength of the smoke, or to be mindful of cost of production having numerous materials.
Many such compositions are also corrosive and damaging to both electronic and mechanical equipment. Finally, some compositions produce an excess of heat and flame, again limiting their usefulness and requiring that additional safety measures be taken. For these reasons, conventional smoke-producing compositions are found to be inadequate.
Therefore, there is a need to replace existing dyes in smoke producing compositions with at least one dye that has been shown to be less toxic. There is also a need to replace the sulfur fuel with a less toxic and environmentally friendly alternative. Finally, there is a need to do all this while still creating comparable signaling color and meeting the burn time requirements for the M18 grenade specification, and if possible to reduce the cost of producing such the smoke grenade.

Low toxicity, environmentally friendly violet smoke generating compositions and methods of making the same

The United States of America as Represented by the Secretary of the Army