A heat exchanger tube manufacturing method to manufacture heat exchanger tubes in a production line. The method includes the steps of molding a plurality of dimples in a plate material, which is payed out continuously, folding back the molded plate material along an axis extending in the direction in which the plate material is payed out to form the molded plate material into an intermediate tube body and cutting the intermediate tube body into parts of a predetermined length.

1. Field of the Invention
This invention relates to a method of manufacturing heat exchanger tubes (for example, a radiator, a condenser or an evaporator for an automobile) from a plate material payed out continuously, and a dimpling roll used for the same manufacturing method.
2. Description of the Prior Art
A heat exchanger tube enables the heat on the inside and outside thereof to be exchanged with each other by a heating medium circulated inside thereof as the outflow of the heating medium to the outside of the heat exchanger tube is prevented, and cools an apparatus or an engine or sets the temperatures thereof constant. A heat exchanger tube is used for a radiator, a condenser or an evaporator of an automobile. To manufacture this heat exchanger tube, a method of, for example, Japanese Patent Laid-Open No. 028438/1992 is used.
The manufacturing method of Japanese Patent Laid-Open No. 028438/1992 is as follows. This method comprises a plate material dimple-molding step, a cutting step and a bending step, and, during the cutting step, some groups of dimples in a dimple-molded portion are removed, whereby the dimple-removed portions are formed into flat remolded portions corresponding to end portions to be cut of the plate material. A portion corresponding to an end portion to be cut is remolded into a flat portion so as to improve the sealability thereof as an end portion of a heat exchanger tube inserted into an insertion port of a heat exchanger and soldered thereto. According to the techniques which had been utilized before Japanese Patent Laid-Open No. 028438/1992 was published, dimples had also been molded in a cut end portion, so that the sealability of the same end portion soldered to a heat exchanger body had been low.
The invention disclosed in this Japanese Patent Laid-Open No. 028438/1992 can provide a heat exchanger tube capable of easily improving the sealability thereof with respect to a heat exchanger tube. However, since a tube body is formed by bending a plate material after the plate material is cut off, a bending process demands a high accuracy, and a bending operation is difficult to be carried out. This causes a fear of making a cut end portion deviate from an. insertion port of a heat exchanger body, and exerting a bad influence upon a cut end portion inserting operation. Moreover, the elongation, which occurs because cut plate materials flow on a production line, of the cut plate materials in the direction in which a raw plate material is payed out, and a scatter of the dimensional accuracy of cut end portions cannot be ignored. A heat exchanger tube usually demands a dimensional accuracy of xc2x10.2 mm. Therefore, the elongation of a plate material causes the dimensional accuracy of heat exchanger tubes to scatter. Under the circumstances, a heat exchanger tube manufacturing method has been including which is capable of solving these problems, and manufacturing a heat exchanger tube with a high accuracy as the sealability thereof as a heat exchanger tube inserted into a heat exchanger body is maintained.
The present invention relates to a heat exchanger tube manufacturing method for a production line, including a dimpling step of molding a plurality of dimples in a plate material, which is payed out continuously, so as to form the plate material into a molded plate material, a tube body manufacturing step of folding back the molded plate material around an axis extending in the direction in which the plate material is payed out, so as to form the molded plate material into an intermediate tube body, and a step of cutting this intermediate tube body into parts of a predetermined length, the dimpling step including providing the plate material with non-molded sections, in which the dimples are not molded, at predetermined intervals, the cutting step including cutting predetermined parts to be cut of the non-molded sections. The cutting step also includes forming recesses in cut end portions of heat exchanger tubes. The portions to be cut and the portions in which the recesses are to be formed of the intermediate tube body continuously fed are set on and provided in the non-molded sections thereof. To set and provide such portions, reference marks are provided in predetermined positions on the non-molded sections for the purpose of improving the processing accuracy.
According to the present invention, an intermediate tube body obtained by bending a plate material is cut first, so that the problems concerning the processing accuracy are solved. Namely, since the portion of a predetermined range of the plate material which extends from a cut end thereof to a certain extent is formed as a non-molded section, a remolding operation is not required, and both the processing accuracy and sealability of a tube end portion can be set to proper levels. Moreover, the non-molded sections absorb the elongation of the intermediate tube bodies flowing on a production line, and minimize a scatter of the dimensional accuracy of the cut ends. Since the portions to be cut are set additionally on the non-molded sections, the intervals of cut ends can be set certainly in agreement with the length of heat exchanger tubes. The non-molded sections are formed on a plate material by a dimpling roll which constitutes a processing unit used in a dimpling step when heat exchanger tubes are manufactured from a plate material continuously payed out, and which comprises a pair of toothed rolls having toothless non-molded surfaces the rolling cycles of which agree with each other.

Heat exchanger tube manufacturing method


The invention is directed to novel tripod having a fast opening and positioning mechanism configured to allow a user to open said tripod in a photographing location while maintaining eye contact with an object to be photographed, said tripod comprising legs having telescopic segments and a central locking mechanism operated by a handle having a trigger connected to a loaded spring positioned on a central column, wherein upon pressing on said trigger said central locking mechanism is unlocked to allow spacing of said tripod legs and free fall of said telescopic segments of each one of said legs towards the ground according to the height of the ground in the vicinity of each of said legs, and wherein upon sliding of said handle downward along said central column, said legs with said extended segments become locked in an open form.

The present invention is in the field of photography equipment. More specifically the invention relates to tripods having a novel central mechanism for opening/closing the tripod and extending/retracting the leg segments that provides a user with a fast, simple and convenient way to open and deploy the tripod upon photographing, repositioning the tripod in the photography site, and packaging the tripod after the work is completed.
Tripod supports for photographic and other equipment are well known. Many variations have been developed to address issues of stability, weight, adjustability, reliability, cost, and ease of use. Trade-offs involving these factors have been made in the past. However, there is much room for innovation as these trade-offs have reached diminishing returns.
Most development in recent years has focused on providing tripods with enhanced stability and reliable operation. Little has been done to improve the ease of use that is cumbersome and occupies the photographer's attention instead of allowing him/her to focus on the shots he/she should take. The time required for opening/closing and positioning the tripod is sometimes crucial when photographing a real-time event with no repeat options.
Currently, most tripods known in the art are opened and deployed at the photography site manually i.e., the user has to open each leg of the tripod separately and unlock/lock each leg segment separately, and adjust the length of the tripod to the surface structure that it is positioned on.
Some attempts were made in the art to allow for a less cumbersome process of opening/closing of tripods. Some examples of such attempts are disclosed in the following patents and patent applications: JP2006170424 (A), WO2012030391, WO9920933, U.S. Pat. No. 6,793,191, U.S. Pat. No. 7,086,631, and CN201731245.
Thus, it is obvious that a mechanism, capable of simplifying the opening/closing and deploying of a tripod is desired. The present invention is aimed at providing such a mechanism.

Tripod with fast opening and closing mechanism and methods of use


A method of managing a supply chain comprises providing at a customer interface module a plurality of order fulfillment options to a customer, and receiving from the customer a selection of a particular order fulfillment option. The method also includes receiving a first order from the customer, and receiving a first inventory status from a first distribution center. A first distribution center sends a first product to the customer in response to determining that the particular order fulfillment option comprises a fill-partial order fulfillment option, and a duration between the time that the first product is directed to be sent and the time when the first product is actually sent is determined. An alert is generated if the duration is greater than a predetermined duration.

A provider of products and services uses a supply chain to deliver the products and services to their customers. For example, a mobile communication network service provider builds and maintains the network, including one or more base station subsystems, a network switching subsystem, and a core network subsystem. The service provider manages a supply chain that includes products and suppliers to build and maintain the mobile communication network, and products and suppliers of the mobile devices that the subscribers use to access the network. Thus the supply chain for a mobile communication network includes a wide variety of products and services, distributed over a wide geographic area, and distributed through a large number of outlets including warehouses, retail stores, Internet-based electronic commerce sites, and others.
The use of the same reference symbols in different drawings indicates similar or identical items.

System and method for vendor and customer management in a supply chain


A stable aqueous suspension of composite particles each including a core formed from a solid or liquid particle and a coating layer formed on the core particle and including at least one high molecular weight surfactant compound having an average molecular weight of 1100 or more and at least one low molecular weight surfactant compound having an average molecular weight of 1100 or less and at least 400 below the average molecular weight of the high molecular weight surfactant compound and optionally a suspension stabilizer, is produced by subjecting a particulate solid substance or a liquid substance to a suspending treatment in an aqueous medium containing the above-mentioned high and low molecular weight surfactant compounds, and optionally the suspension stabilizer.

(1) Field of the Invention
The present invention relates to an aqueous suspension of composite particles and a process for producing the same. More particularly, the present invention relates to a suspension of composite particles containing core solid particles or core liquid droplets in an aqueous medium in which the solid particles or liquid droplets-containing composite particles are suspended with a high storage stability, and even when the composite particles are precipitated, they can be easily re-suspended, and a process for producing the same.
(2) Description of the Related Art
It is known that an aqueous suspension of solid particles, for example, particulate agricultural chemicals, or liquid droplets, for example, an oil, can be prepared by the following methods.
For example, Japanese Examined Patent Publication No. 46-20,519 discloses a method in which a hydrophobic agricultural chemical is wet-pulverized in water or a hydrophilic medium and the resultant hydrophilicized fine particles are suspended in the medium. Japanese Examined Patent Publication No. 58-2,440 discloses an aqueous suspension of an agricultural chemical comprising a solid agricultural chemical having a poor solubility in water or a combination of a solid agricultural chemical having a poor solubility in water with a water-soluble solid agricultural chemical; a surfactant, a water-soluble high molecular compound and water, and having a viscosity of 200 to 500 cP at a temperature of 20.degree. C.
Japanese Unexamined Patent Publication No. 57-58,601 discloses a suspension agricultural chemical comprising an agricultural chemical insoluble or scant soluble in water or organic solvents, a surfactant, a xanthane gum and water.
Japanese Unexamined Patent Publication No. 2-111,703 discloses a suspended agricultural chemical comprising a water-insoluble or scant soluble agricultural chemical, a surfactant, a water-soluble biopolymer and water.
Japanese Examined Patent Publication Nos. 7-47,521, 7-47,522, 64-7,041, 63-58,802, and 6-78,202 disclose aqueous suspension agricultural chemicals comprising a herbicide or biocide chemical and a surfactant.
Japanese Unexamined Patent Publications No. 5-201,801, No. 6-9,302 and No. 7-157,401 disclose an aqueous suspension agricultural chemical comprising a herbicide-active component or an other agricultural chemical component and a surfactant, and at least one member selected from thickeners, salts, clay minerals and metal oxide gels.
Japanese Unexamined Patent Publication No. 58-162,504 discloses an aqueous herbicide emulsion containing a liquid herbicide and a surfactant.
Japanese Unexamined Patent Publication No. 6-316,502 discloses a method of suspending a water stint soluble, solid, physiologically active substance in a liquid medium containing a nonionic surfactant having an HLB of 1 to 9 and a nonionic surfactant having an HLB of 10 to 20, the liquid medium optionally containing a clay mineral such as bentonite.
It is also known that where an aqueous suspension of solid or liquid particles is prepared, the storage stability of the aqueous suspension is variable depending on the average particle size of the particles. Also, it is believed that unless the substance to be suspended is divided to an extent such that the resultant average particle size is in the range of from 0.5 to 5 .mu.m, it is difficult to stably suspend the pulverized substance particles in a suspension medium. Therefore, to enhance the stability of the particle suspension, the substance must be finely pulverized, and thus for the fine pulverization, a specific pulverizing machine, for example, Dyno mill, air mill, hammer mill, tower mill, vibration mill or sand mill must be employed. This necessity causes the suspension cost to be high. Also, the higher the content of the particles in the suspension, the higher the viscosity of the suspension. Therefore, an aqueous suspension of fine particles having an average particle size of 0.5 to 5 .mu.m exhibits a high viscosity and thus is difficult to practically use the suspension. Namely, in the preparation of a suspension of solid or liquid particles which are insoluble or stint soluble in water, practically there is an upper limit to the content of the particles. Further, since the finely divided solid or liquid particles have a large surface area and thus the dissolution rate in water or hydrolysis rate increases, the suspension stability of the particles decreases in response to an increase in the surface area of the particles. Accordingly, in the conventional technique, an aqueous suspension of the solid or liquid particles capable of satisfying all of the requirements of high dispersion stability over a long period, high restriction of hydrolysis of the particles and a high re-suspending property of the particles has not yet been obtained.
Further, in fields of pigments, medicines, cosmetics, dyestuffs, paints and building materials which may be solid or liquid, when they are used in the state of a suspension in an aqueous medium, or the aqueous suspension is used as a starting material, it is strongly required that the aqueous suspension exhibits a high storage stability over a long time and even where a portion of the particles is precipitated during long time storage, the precipitated particle portion can be easily re-suspended. However, the aqueous suspension capable of satisfying all of the requirement has not yet been obtained.

Composite particle aqueous suspension and process for producing same


A double-ended utility knife having a housing or handle including an elongated, generally rectangular base member with a first end, a second end, a front side, and a back side is disclosed. The front side of the base member has a front compartment and a cover and the back side has a back compartment with a cover where the covers are attached to the front and back sides, respectively. Each of the compartments and covers extends less than the total length of the base member and is located at opposite ends of the base member. Each cover is secured to the base member by its own screw so that only one cover need be removed in order to replace a blade. Blades extend from both ends of the housing and have their own actuator so that each blade may be extended or retracted independently of the other.

The present invention is directed toward a utility knife, and more particularly toward a utility knife with a blade at both ends of the knife, where each blade may be activated independently of the other. The utility knife also has a housing with a cover on both sides of the housing where each cover may be removed independently of the other.
Typically, a utility knife has a housing which may be separable into two halves along the length of the housing so that the blade may be replaced with a new blade or a different type of blade, depending upon the user's needs.
Utility knives are also known to have two blades which are retractable. The blades may be next to each other or they may be on both ends of the knife. The knives with dual blades usually have two different blades so that two different functions may be performed, one after the other without the user having to waste time switching the blade, thereby enabling a person to work more accurately, quickly, and with minimal interruption.
The problem with these knives is that the entire housing must be disassembled in order to replace the blades. Both blades are necessarily exposed when perhaps only one blade needs to be replaced. Thus, a person is unnecessarily exposed to injury. Furthermore, one blade can be dislodged and fall out while the other blade is being replaced.
U.S. Pat. No. Des. 310,474 to Bartsch et al discloses a double-ended knife with a straight blade at one end and a hooked blade at the opposite end, each blade having its own actuator. The entire housing, however, must be dismantled in order to replace either one of the blades.
U.S. Pat. No. 5,093,994 to Karas discloses a double-ended retractable knife with a housing having two halves held together by a fastener. Both ends of the knife have a blade where one blade may be hooked and the other straight. The fastener must be removed in order to replace the blades, thereby exposing both of the blades even though both blades may not need to be replaced.
U.S. Pat. No. 4,578,865 to Keller discloses a knife with two blades parallel to each other with one actuator. The housing or handle of the knife must be separated in order to replace the blades.
U.S. Pat. No. 5,337,481 to Mears discloses a utility knife with two blades, each blade having its own actuator so that each blade may be activated independently of the other. The blades are also parallel with each other. Again, however, the entire housing must be separated in order to replace the blades.

Double-ended utility knife with two covers


Methods and compositions for enhancing the activity and/or duration of action of loteprednol etabonate and other soft anti-inflammatory steroids of the haloalkyl 17α-alkoxycarbonyloxy-11β-hydroxyandrost-4-cn-3-one-17β-carboxylate type and the corresponding Δ1,4-compounds are described. The enhancing agents have the formula:

1. Technical Field of the Invention
The invention relates to enhancing the activity and/or the duration of action of particular anti-inflammatory steroids for topical or other local application, including ophthalmic application for the treatment of dry eye.
2. Background Art
Topical or other local application of potent glucocorticoids can produce severe toxic effects such as Cushingoid features, pituitary-adrenal suppression, skin atrophy, immunosuppression, weight gain and inhibition of wound healing. Other kinds of toxic responses, including allergies and cataracts, have resulted from long term use of drugs of this type.
Ophthalmic application of glucocorticosteroids presents additional problems The protective mechanisms built into the eye allow only small amounts of doses applied to the eye to reach the target sites within the eye; generally, over 90 percent of the total dose will find its way into the general circulation. This in turn leads to serious systemic side effects of the type described above. Moreover, there is a more serious and specific side effect when these drugs are used in the eye, which is an increase in intraocular pressure (IOP). Corticosteroid-induced chronic or acute glaucoma has in fact been reported since the early 1960's. Generally, the corticosteroid is needed only topically to control the inflammation. However, the absorbed steroid is responsible for the serious side effects noted above. It is believed that the effect of the corticosteroid, on the aqueous outflow pathway and adjacent, tissue glycosaminoglycans (GAG's) is important in the development of glucocorticoid-induced ocular hypertension.
The natural glucocorticosteroids and many of their marketed derivatives are Δ4 and Δ1,4 pregnenes having 21-hydroxy substituents. There are, however, a number of anti-inflammatory Δ4 and Δ1,4 androstenes described in the literature; note, for example, British Patent Specification No. 1,384,372; Phillipps et al. U.S. Pat. No. 3,828,080 and Kalvoda et al. U.S. Pat. No. 4,285,937.
In recent years, soft steroids have been developed in an effort to provide compounds having potent anti-inflammatory activity with minimal systemic activity. One series of soft steroids which is described as having potent an anti-inflammatory activity with minimal systemic activity consists of the 17α-carbonates of Bodor U.S. Pat. No. 4,996,335. These compounds include as preferred embodiments haloalkyl 17α-alkoxycarbonyloxy-11β-hydroxyandrost-4-en-3-one-17β-carboxylates and the corresponding Δ1,4 compounds, optionally bearing 6α- and/or 9α-fluorine and 16α- or 16β-methyl substituents. One of these compounds is chloromethyl 17α-ethoxycarbonyloxy-11β-hydroxyandrosta-1,4-dien-3-one-17β-carboxylate, also known as loteprednol etabonate. Loteprednol etabonate is presently marketed in the United States by Bausch & Lomb Pharmaceuticals, Inc. as Alrex® and Lotemax® and combined with tobramycin as Zylet® for ophthalmic use. Other uses of loteprednol etabonate are currently in clinical trials (for rhinitis and various dermatological conditions). Mention is also made of Bartels United States Patent Application Publication No. 2005/0222110, which describes the use of loteprednol etabonate itself for the treatment of dry eye, the contents of which is incorporated by reference herein in its entirety and relied upon; Pfugfelder et al.'s description of clinical trials utilizing 0.5% loteprednol etabonate suspension for treating keratoconjunctivitis sicca (Am. J. Opthalmol: 2004, 138(3), 444-457); and WO 03/030893, drawn to methods of treating dry eye by administering combinations of MUC-1 secretagogues, such as HETE derivatives, and anti-inflammatory steroids, one of which is loteprednol, this document also being incorporated by reference herein in its entirety and relied upon. See also Optometric Management, February 2005 in which Dr. Ron Melton is quoted as saying "Loteprednol 0.5% has revolutionalized the way we treat dry eye" (accessed at http://www.optometric.com/article.aspx?article=71289 on Jul. 12, 2007). Other publications relating to methods and compositions for treating dry eye utilizing loteprednol etabonate and compositions comprising it include Meyering U.S. Patent Appln. Publication No. 2005/0182039; Gamache et al. U.S. Patent Appln. Publication No. 2006/0069075; Xia et al. U.S. Patent Appln. Publication No. 2006/0148686 and Chappell et al. U.S. Patent Appln. Publication No. 2007/0105761, all incorporated by reference herein in their entireties and relied upon.
Despite the development of steroids having less systemic toxicity, however, there is a serious need for improvement in topical and other local applications. The newer, less toxic, locally/topically active compounds are more expensive to synthesize than the long-established compounds. Moreover, the most potent anti-inflammatory steroids are those which have substitution at the 6, 9 and/or 16-positions and thus also not only are farthest removed structurally from the natural corticosteroids but also have the greatest toxicity. Thus, there is a need for enhancing the activity or duration of action or both of the 17α-carbonate type soft androstenes which lack the 6-, 9- and/or 16-substitution pattern. Further, it would be desirable to allow these steroids to undergo easier metabolism and concentrate them at the desired site of action.
One of the major, inactive metabolites of hydrocortisone is cortienic acid, i.e. 11β,17α-dihydroxyandrost-4-en-3-one-17β-carboxylic acid Cortienic acid and the corresponding Δ1,4 acid have been previously described as synthetic intermediates useful in the preparation of the soft steroids described in Bodor U.S. Pat. Nos. 4,710,495 and 4,996,335. The 17β-methyl, ethyl and isopropyl esters of Δ1-cortienic acid have been described as putative inactive metabolites of the anti-inflammatory androstene derivatives of WO 97/42214 and Bodor U.S. Pat. No. 5,981,517. The '517 patent also describes the use of Δ1-cortienic acid as a competitor (with [3H]-triamcinolone acetonide as a tracer) for in vitro receptor-binding studies of the androstene derivatives of that patent and notes similar studies of loteprednol etabonate. Druzgala et al., J. Steroid Biochem. Mole. Biol., Vol. 38, No. 2, pp 149-154 (1991), reports earlier in vitro receptor binding studies of loteprednol etabonate and two putative metabolites, Δ1-cortienic acid and the corresponding 17α-ethyl carbonate, in a medium containing 10−5M cortienic acid as competitor, along with [3H]-triameimolone acetonide as tracer. Druzgala et al. further note that loteprednol itself is intrinsically active, whereas the putative metabolites are indeed inactive. Neither these acids nor their esters have been suggested as active ingredients for use in pharmaceutical compositions for the treatment of inflammation because they are not themselves active as anti-inflammatory agents. However, such inactive metabolites have been described as enhancing the anti-inflammatory activity and duration, of action of loteprednol etabonate and related soft steroids in Bodor United States Application Publication No. 2005/0026892A1, published Feb. 3, 2005. Such inactive metabolites have also been described as enhancing the anti-inflammatory activity and duration of action of selected other corticosteroids, for example, hydrocortisone; see Bodor United States Application Publication No. 2005/0020551 A1, published Jan. 27, 2005.
Nevertheless, there remains a need for alternate methods and compositions for enhancing the anti-inflammatory activity and duration of action of loteprednol etabonate and related soft, steroids.

This patent is subject to a terminal disclaimer.

Transporter-enhanced corticosteroid activity and methods and compositions for treating dry eye

Abstract: wherein Z1 is carbonyl, β-hydroxymethylene or methylene; R2 is H, —OH or —OCOR3 wherein R3 is C1-5 alkyl; Y is —OH, —SH or —OCOR4 wherein R4 is C1-5 alkyl, cyclopentylethyl or diethylaminoethyl; and the dotted line in ring A indicates that the 1,2-linkage is saturated or unsaturated. Ophthalmic administration in the treatment of dry eye is specifically targeted.


A method of and system for visualizing a sound source is disclosed. The method may include analyzing an audio signal received by a sound transducer to determine a positional direction of the sound source, determining whether the positional direction of the sound source falls outside a field of view of a user, and in response to determining that the positional direction of the sound source falls outside the field of view of the user, rendering on a display unit a visual representation of the sound source. The visual representation of the source is rendered on a virtual surface at a location within the field of view of the user, the location corresponding to at least one of a distance of the source from the user and a positional direction of the source with respect to the user.

A large number of people in the world suffer from mild to severe hearing impairment. Often people with hearing impairment rely on other senses such as vision to interpret their environment. As a result, it may be particularly challenging for people who suffer from hearing impairment to notice events that occur outside of their field of view. This may also be true for people with normal hearing that work in noisy environments, particularly if they are focusing on a task that requires their full attention. People that utilize devices that provide virtual reality (VR), augmented reality (AR), and/or mixed reality (MR) may also have trouble paying attention to events that occur outside their field of view as the environments generated by these devices may consume all their attention (e.g., an immersive environment). This may result in the user being unaware of important and/or dangerous sounds that originate from outside their field of view.
Hence, there is a need for improved methods and system of notifying people with hearing challenges of sounds that originate from outside the person's field of view.


A method for converting carbon dioxide in flue gas into natural gas using dump energy. The method includes: 1) transforming and rectifying a voltage of dump energy generated from a renewable energy plant, introducing the voltage-transformed and rectified dump energy into an electrolyte solution to electrolyze water therein to yield H2 and O2; 2) purifying industrial flue gas to separate CO2 therein and purifying CO2; 3) transporting H2 generated and CO2 to a synthesis equipment, allowing a methanation reaction between H2 and CO2 to happen to yield a high-temperature mixed gas with main ingredients of CH4 and water vapor; 4) employing the high-temperature mixed gas to conduct indirect heat exchange with process water to yield superheated water vapor; 5) delivering the superheated water vapor to a turbine to generate electric energy, and returning the electric energy to step 1); and 6) condensing and drying the mixed gas.

1. Field of the Invention
The invention relates to technology for energy conversion of industrial flue gas using dump energy arising from renewable energy generation, and specifically relates to a method and a device for converting carbon dioxide in flue gas into natural gas by dump energy.
2. Description of the Related Art
There is an ongoing need to make full use of the dump energy arising from renewable energy generation and further to effectively reduce the greenhouse effect.

Method and device for converting carbon dioxide in flue gas into natural gas

Wuhan Kaidi Engineering Technology Research Institute Co., Ltd.


A reactor for plasma-enhanced chemical vapor deposition having a showerhead electrode facing the wafer being CVD deposited, the showerhead having a large number of jetting holes for jetting processing gas towards the wafer. Two deep grooves are formed around the area of the showerhead containing the jetting holes. The grooves are formed from opposite sides of the showerhead and are radially offset from each other, thereby forming a thin wall between the grooves in the body of the showerhead. The thin wall acts as a thermal choke, thus reducing the heat flow to the support of the showerhead and also rendering the temperature distribution more uniform across the face of the showerhead. The thin wall further acts as a mechanical bellows to accommodate differential thermal expansion between the showerhead and its support.

Chemical vapor deposition (CVD) is a well known process for the fabrication of semiconductor integrated circuits and other layered structures formed on a substrate. In CVD, the semiconductor wafer or other substrate is exposed to a precursor gas at a reduced pressure inside a vacuum chamber. The precursor gas reacts at the surface of the wafer and deposits a component on the wafer. For example, silane (SiH.sub.4) is often used as the precursor gas for depositing silicon, and TEOS (tetraethylorthosilicate) is often used for silicon dioxide. There are two principal ways of driving the reaction. If the wafer is heated to a sufficiently high temperature, the reaction is thermally activated. However, for many applications, the temperature necessary for an efficient rate of thermal activation is considered to be too high. In an alternative method, called plasma-enhanced CVD or PECVD, electrical means are used to excite the precursor gas into a plasma. The plasma creates ions and/or radicals of the precursor gas and its components, and these much more readily react. Thereby, the temperature of the wafer can be held fairly low.
An example of a PECVD reaction chamber is described by Zhao et al. in U.S. Pat. No. 5,558,717, incorporated herein by reference. This type of CVD reactor is available from Applied Materials, Inc. of Santa Clara, Calif. under the name DxZ chamber. The CVD reactor of the patent is illustrated in the cross-sectional view of FIG. 1. An unillustrated wafer is supported during processing on a pedestal 10, which can be lowered for the loading and unloading of the wafer into and out of the vacuum chamber through a slit-valve opening 12 in a lower chamber body 14 and a ceramic ring 16 inside the lower chamber body 14.
During deposition, a precursor gas 18 flows through a center-feed distribution system overlying the wafer and through a large number (several thousands) of jet holes 20 in a faceplate 22 composed of a conductive metal, such as aluminum. The gas distribution system is described by Schneider et al. in U.S. patent application Ser. No. 08/734,015, filed Oct. 18, 1996 and entitled INDUCTIVELY COUPLED PARALLEL-PLATE PLASMA REACTOR WITH A CONICAL DOME. The front portion of the faceplate 22 containing the jet holes 20 is called a showerhead 24. As illustrated, during processing the showerhead 24 is closely opposed to the wafer, and its perforated area extends substantially coextensively with the area of the wafer. The processing gas flows through the showerhead holes 20, over the wafer, and then generally radially outwardly to an annular pumping channel 26, generally surrounding the upper edge of the pedestal 10 during processing. The spent gas is exhausted through a restriction 28 in the pumping channel 26 to an exhaust manifold 29. A valve 30 gates the exhaust to an exhaust vent 32 which is pumped by an unillustrated vacuum pumping system.
The faceplate 22 and associated parts are held in a lid frame 34, which is sealed to the lower chamber body 14 by O-rings 36. The lid frame 34 pivots about an unillustrated horizontal hinge and thus can be raised away from the lower chamber body 14 in order to allow technicians to service the interior of the chamber. As shown, the pumping channel 26 is formed between the lid frame 34, the lower chamber body 14, and a second ceramic ring 38 supported through the first ceramic ring 16 on the chamber body 14, but the pumping channel 26 mainly extends into the lid.
The illustrated reactor is intended to be used as a plasma reactor. The pedestal 10 is typically grounded while a cover 40 both electrically and mechanically fixed to the faceplate 22 is connected to an RF power supply 42. Thus, a processing space 44 is surrounded by RF-driven electrodes consisting of the showerhead 24 and the pedestal 10. Sufficient RF power is applied so that the process gas in the processing space 44 between the showerhead 24 and the pedestal 10 is excited into a plasma to activate the CVD reaction on the surface of the wafer. Thereby, the reaction can be carried out at relatively low temperatures with little effect on the thermal budget of the integrated circuit being formed.
The lower chamber body 14 is usually made of a metal such as aluminum and, for safety reasons, is electrically grounded. An annular isolator 46 electrically isolates the RF-driven faceplate 24 from the lid frame 34 and the lower chamber body 14, to which it is electrically connected. The isolator 46 is formed either of a ceramic material, such as alumina or of a sturdy plastic, such as Teflon, both of which provide good electrical isolation.
The chamber of FIG. 1 was designed for 200 mm (8-inch) wafers. Scaling these chambers up for 300 mm (12-inch) wafers presents further problems as well as an opportunity to improve the basic design.
In the reactor of FIG. 1, the temperatures of the faceplate 22 and its showerhead 24 are not tightly controlled. The pedestal 10 is actively heated by resistive coil, but the faceplate 22 is not actively heated or cooled. The temperature of the showerhead 24 is estimated to be about 200.degree. C. because of collisional heating from the plasma and radiative heating from the pedestal 10. Although the temperature tends to equilibrate between the pedestal 10 and the showerhead 24, some of the showerhead heat is sunk through the outer and upper portions of the faceplate 22 to the lid frame 34 and eventually to the lower chamber body 14, as well as to other peripheral attached parts.
Such temperatures are not extreme, but they still cause reliability and lifetime problems in the O-rings sealing the faceplate 22, the lid frame 34, chamber body 14 and other parts. It is thus desirable to reduce the temperature at the back of the faceplate 22.
The heat sinking at the circumference of the showerhead causes at least two related problems. Heat production is substantially uniform over the area of the showerhead, and heat flows to the cooler circumferential area over a path having a substantially uniform thermal conduction. As a result, the center of the showerhead 24 has a higher temperature than the showerhead portions nearer the circumference. The radial non-uniformity in temperature affects the uniformity of the deposition rate and also introduces thermal stresses into the showerhead 24. The thermal stresses cause the showerhead 24 to bow, and the resultant variable gap size of the processing space introduces a non-uniform plasma, yet another source of non-uniformity in deposition. These temperature non-uniformities significantly worsen for the larger wafer sizes.

Faceplate thermal choke in a CVD plasma reactor


Methods for the formation of colloidal suspensions. The method includes combining an aqueous substance with a second substance that is normally immiscible with the aqueous substance, to form a mixture, and before, during or after the combining removing dissolved gases from one or both of the aqueous and second substance, whereby the aqueous and second substances mix and form a colloidal suspension. The methods for the formation of colloidal suspensions include methods for the formation of emulsions as well as particulate dispersions. The methods used to form the colloidal suspensions in accordance with the present invention produce colloidal suspensions that are stable for periods from an hour to several weeks in the absence of surfactants or stabilizing agents.

The present invention relates to the formation of emulsions and dispersions, and in particular, to the process of formation of stable oil emulsions and particulate dispersions of hydrophobic materials in aqueous substances.
Everyday "common knowledge" tells us that oil and water do not mix. This fact is assumed to be related to the different properties of the two materials. Oil being nonpolar is "hydrophobic" and therefore water-hating. This view is certainly valid for molecular mixtures of oil and water. Simply put, the work required to force apart hydrogen-bonded water molecules to incorporate hydrocarbon solute molecules is too large and this work is not compensated by a strong solute-water bonding, which is the case for soluble solutes such as common salt, sugar and ethanol. Each of the latter solutes can form strong bonds with adjacent water molecules, which replace those between the water molecules themselves.
Another type of mixture, not molecular in nature, can be formed by the dispersion of microscopic droplets or particles, often in water, to form a colloidal solution or dispersion. However, hydrocarbon oils and finely divided hydrophobic particles will not readily disperse in water and will only remain stable for a short length of time, typically, for less than an hour, even after vigorous mechanical agitation. Thus, most industrial processes involving these mixtures require continuous agitation and fairly rapid reaction times. The efficiency of these processes is also reduced by the difficulty in maintaining small particle sizes and a high reaction surface area, because of the tendency to coalescence and coagulation. The stability of emulsions and dispersions can be much improved by the addition of surfactants and polymers, which can change the nature of the oil/water interface. However, these observations are, at first sight, not consistent with a simple application of the well-established DLVO theory of colloid stability (J. N. Israelachvili, Intermolecular and Surface Forces, Academic Press (1992)). This is because oil droplets and fine, hydrophobic particles, even without additives, are known to develop significant surface electrostatic potentials in water and, in addition, generally have weak van der Waals attractive forces. These conditions usually indicate that the colloidal dispersion will be stable.
It is, therefore, of some interest to consider in more detail why hydrophobic colloids, such as fine oil droplets, fail to maintain colloidal stability in water. The molecular force or bonding argument is not valid in this case (although it is directly related to the ultimate thermodynamic stability of the colloidal solution) because colloidal dispersions can be maintained in a meta-stable state by the operation of strong repulsion forces generated between the particles or droplets. The DLVO theory is based on the assumption that it is the charge on a colloidal particle (or droplet) surface which generates a repulsive electrostatic (double-layer) force between particles, which can be of sufficient strength to overcome the ubiquitous van der Waals attractive force. These combined forces can be estimated from the theory using the measured electrostatic potential on the surface of, for example, typical hydrocarbon oil droplets and their van der Waals attraction. The surface potential of dodecane droplets (as well as some other oils) was carefully measured in 1996, (Marinova, K. G. et al., Langmuir 12(8):2045-2051 (1996)), and these values can be used to calculate the expected interaction energy between two oil droplets in water. In order to consider the static forces involved, reference is made to FIG. 1. FIG. 1 gives the estimated DLVO interaction energies expected for 0.3 μm radius dodecane oil droplets in water, using the simplified, i.e., linear (low potential), Poisson-Boltzmann equation, combined with a nonretarded Hamaker attraction and using the Derjaguin approximation (J. N. Israelachvili, Intermolecular and Surface Forces, Academic Press (1992)). This radius was selected because smaller droplets will tend to coalesce through kinetic collisions and larger droplets have a greater buoyancy force and will rapidly coalesce with the upper oil phase. Droplets of 0.3 μm radius will rise at the rate of nearly 0.5 cm per day in water.
The DLVO equation used here to calculate this interaction is given below:
            V      s                  (              /        kT            )        =            a      kT                  [                        2                                                              π                                  ∈          0                                              D                                                                                ψ              0              2                                                  exp                                            (                                                      -                    κ                                                                                H                                )                                              -                                    A              121                                      12                            H                                          ]
where Vs is the interaction energy between spheres in kT units, "a" is the spherical radius, ψ0 is the particle's electrostatic potential, κ−1 is the Debye length, A121 is the Hamaker constant for the system, and H is the interparticle separation distance. ε0D is the permittivity of water. In the dodecane/water system, the calculated barrier is almost 800 kT (see FIG. 1), which would give long-term stability to emulsion droplets of this size (Hiemenz, P. C. et al., Principles of Colloid and Surface Chemistry: New York (1977)). The significant surface potential reported (Marinova, K. G. et al., Langmuir 12(8):2045-2051 (1996)), of between −50 and −60 mV, is apparently caused by the specific adsorption of hydroxyl ions from the aqueous phase to the oil/water surface. The standard theory of coagulation of colloids (Hiemenz, P. C. et al., Principles of Colloid and Surface Chemistry: New York (1977)) indicates that coalescence or coagulation will become significant when the repulsive barrier approaches 10-20 kT or less. Clearly, these simple calculations indicate that fine droplets of hydrocarbon should be indefinitely stable against coalescence in water, because of a combination of surface charging via hydroxyl ion adsorption and a relatively weak van der Waals attraction, a result which is at complete variance with general observation.
Because the interparticle potential energy barrier is proportional to the droplet radius, smaller hydrocarbon oil droplets will readily coalesce, as observed for the fine droplets (less than 50 nm radius) produced by the sonication of oil and water mixtures (Sakai, T. et al., Langmuir, 17(2):255-259 (2001)). Larger droplets will feel a substantial buoyancy force and will readily combine with the upper phase of dodecane liquid, because it has a lower density than water. Droplets of intermediate (micron) sizes should be stable for longer periods, if only DLVO forces operate. Similar stability arguments can be applied to fine Teflon particles, which are known to be charged (Kratohvil, S. et al., J. Colloid Interface Sci., 57(1):104-114 (1976)) and have an even weaker van der Waals attraction in water (with a Hamaker constant of 0.3×10−20 J) (J. N. Israelachvili, Intermolecular and Surface Forces, Academic Press (1992)). The failure of the DLVO theory to predict the behavior of oil in water emulsions raises the issue of whether there might be additional forces involved. About 20 years ago, a new long-range attractive force, called the "hydrophobic interaction" (Israelachvili, J. N. et al., Nature, 300:341-342 (1982)), was discovered which acted over relatively large distances (>10 nm) between hydrophobic surfaces in water. Subsequent workers have extended the range to over 100 nm in some systems.
In later work, it was also suggested that dissolved gases may play a significant role in this interaction (Craig, V. S. J. et al, J. Phys. Chem., 97:10192-10197 (1993); Karaman, M. E. et al., J Phys. Chem. 100:15503-15507 (1996)), which has yet to be properly described by any theoretical model. At normal temperature and pressure, dissolved air in water has a concentration of around 1 mM, corresponding to about 20 mL of dissolved gas in a liter of water. In typical alkanes, gas solubility can be an order of magnitude higher. The role of dissolved gas in the properties of solutions has hardly been considered theoretically and, experimentally, only sporadically and often ignored.
In 1993, it was demonstrated that partial degassing, using a water jet pump aspirator to produce about 97% degassing for mixtures of dodecane/water, increased the stability of oil droplets on vigorous shaking (Craig, V. S. J. et al, J. Phys. Chem., 97:10192-10197 (1993)). These initial observations stimulated an AFM study which attempted to address the issue of dissolved gas in the interaction of hydrophobic polypropylene surfaces (Meagher, L. et al., Langmuir 10(8):2736-2742 (1994)). The polypropylene surfaces used in that study, although very hydrophobic as measured by the water contact angle, generated only a relatively short-ranged attraction measurable up to about 25 nm separations. The effect of degassing was only minor in this case. However, Horn et al. (Considine, R. F., et al., Langmuir 15(5):1657-1659 (1999)) reported a significant decrease in the long-range attraction (20-400 nm) between two polystyrene latexes as the level of dissolved gas in solution was reduced. In further work on emulsion stability, using a water jet pump to degas to the 97% level, it was also demonstrated that dissolved gas plays a significant role in emulsion stability and emulsion polymerization (Karaman, M. E. et al., J. Phys. Chem. 100:15503-15507 (1996)) and this led to the suggestion that dissolved gas may play a significant role in the balance of hydrophobic and hydrodynamic (drainage) forces responsible for the phase separation. By comparison, Zana et al. examined the effects of degassing on surfactant aggregation (Alargova, R. G. et al., Langmuir 14(7):1575-1579 (1998)) and microemulsions (Sierra, M. L. et al., J. Colloid Interface Sci. 212 (1):162-166 (1999)) and reported no effect in either case. However, this is hardly surprising because the amount of dissolved gas present in the aqueous phase, at the mM level, could not possibly be sufficient to influence these high surface area systems. Recently, a study of the coagulation rates of solid paraffin wax mixed with carboxylic acid stabilizer has shown that partial degassing (to about 97% using a water aspirator) has a significant effect on reducing the initial coagulation rates (Alfridsson, M. et al., Langmuir 16(26):10087-10091 (2000)). More recently, Ishida et al. (Ishida, N. et al., Langmuir 16(13):5681-5687 (2000)) have reported the complete absence of a long-range attraction (beyond 10 nm) from force measurements on systems that have never been exposed to dissolved gases.
Unfortunately, the literature produced over the last 20 years contains many reports of force measurements between hydrophobic surfaces with widely differing results, often depending on the preparation of the surfaces and the method used. There is therefore a need to better understand the electrostatic potential on an oil droplet or a hydrophobic particle and whether this potential is sufficient to stabilize fine droplets and to thus enable the formation of stable colloidal suspensions.

Process for the production of emulsions and dispersions


A semiconductor memory device includes a semiconductor substrate, a cell array region storing data on the substrate, a periphery circuit region on the substrate, the periphery circuit region controlling input and output of the data stored in the cell, a plurality of word-lines and bit-lines on the cell array region, and a plurality of dummy pattern layers on the periphery circuit region.

1. Field of the Invention
The present invention relates to a semiconductor device, and more particularly, to a semiconductor memory device and a method of fabricating the same. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for reducing a step coverage between a cell part and a periphery circuit part for a higher integrated semiconductor memory device.
2. Discussion of the Related Art
A conventional semiconductor memory device and a method of fabricating the same will be explained with reference to the accompanying drawings.
FIGS. 1A to 1M are cross-sectional views showing a conventional method of fabricating the semiconductor memory device.
An n-type well and a p-type well are formed in a semiconductor substrate, as shown in FIG. 1A.
In FIG. 1B, an isolation layer 4 for isolating a cell part from a periphery circuit part and a device isolation layer 3 for isolating a cell from one another are formed on predetermined portions of the substrate where the n-type well and the p-type well have been formed.
Subsequently, as shown in FIG. 1C, an ion implantation process is performed into an active region defined by the device isolation layer 3 and the isolation layer 4, in order to adjust a threshold voltage. At this time, the type of transistor, such as an NMOS or a PMOS transistor, determines the types of ions to be implanted.
Next, as shown in FIG. 1D, a word-line of a memory device is formed in the cell part. At this time, a gate is formed in the cell part as well as in the periphery circuit part. The word-line includes a gate insulating layer 5, a polygate 6, and a cap oxide layer 7 on the substrate.
Thereafter, as shown in FIG. 1E, a buffer oxide layer 8 is formed on the substrate excluding the cell transistor. The buffer oxide layer 8 serves to relieve stress imposed over the substrate during the ion implantation process. With the gate serving as a mask, ions are implanted to form lightly-doped impurity diffusion regions 9 for a source and a drain.
Then, a sidewall oxide layer 10 is formed on both sides of the gates, as shown in FIG. 2F. With the sidewall oxide layer 10 and gate serving as masks, an ion implantation process is carried out to form heavily-doped impurity diffusion regions having a lightly doped drain (LDD) structure. A first insulating layer 11 is then formed on the entire surface of the substrate where the cell transistors have been formed. Subsequently, a second insulating layer 12 made of boron phosphorus silicate glass (BPSG) is formed on the first insulating layer 11. Next, the first and second insulating layers 11 and 12 are selectively removed to form a bit-line contact hole 13.
In FIG. 1G, a polysilicon layer 14 doped with n-type impurity ions and a tungsten silicide layer 15 are deposited to completely bury the bit-line contact hole 13 and then selectively patterned to form a bit-line.
Thereafter, as shown in FIG. 1H, a third insulating layer 16 made of oxide is formed on the entire surface including the bit-line. A fourth insulating layer 17 made of nitride is deposited on the third insulating layer 16. Thereafter, a fifth insulating layer 18 made of BPSG is formed on the fourth insulating layer 17. Then, a sixth insulating layer 19 of oxide is formed on the fifth insulating layer 18. The insulating layers 19, 18, 17, 16, 12, and 11 at the other side of the cell transistor are partially removed to form storage node contact holes 20. Subsequently, a nitride sidewall 21 is formed on side surface of each of the storage node contact holes 20.
Next, as shown in FIG. 1I, storage node electrodes 22 are formed to respectively contact the impurity diffusion regions exposed by the storage node contact holes 20 at the other side of the cell transistor, and then the fifth and sixth insulating layers 18 and 19 are removed with wet-etching. A high dielectric layer 23 is then formed on the entire surface including the storage node electrodes 22.
Thereafter, as shown in FIG. 1J, a plate electrode 24 is formed on the storage node electrode 22 where the high dielectric layer 23 has already been formed.
Then, as shown in FIG. 1K, a seventh insulating layer 25 of oxide is formed on the entire surface including the cell transistor and capacitor for multi-wirings. Aluminum and anti-reflection layers are formed on the seventh insulating layer 25 and then selectively etched to form lower wiring layers 26. At this time, transistors and wiring layers are also formed in the periphery circuit part.
Next, as shown in FIG. 1L, an interlayer insulating layer 27 is formed on the entire surface including the lower wiring layers 26, and then a spin on glass (SOG) layer 28 is coated on the interlayer insulating layer 27. The interlayer insulating layer 27 is then etched-back to improve the step coverage of the device. Subsequently, an eighth insulating layer 29 of oxide is formed on the SOG layer 28. An interlayer contact hole 30 is formed by removing the eighth insulating layer 29, the SOG layer 28 and the interlayer insulating layer 27 to expose the lower wiring layer 26 over the periphery circuit region.
In FIG. 1M, a plug layer 31 is formed in the interlayer contact hole 30 to improve the electrical characteristics of wirings. Then, an upper wiring layer 32 made of aluminum and anti-reflection layer is formed to contact the plug layer 31.
The above-mentioned method has been used for mass production of DRAM devices having a capacitor over bit-line (COB) structure. However, in the conventional method, defective devices are frequently produced due to electrical short circuit in metal wirings in realizing high integration and super micronization. In particular, the main cause of the short circuit is caused by the step coverage between a cell part where a cell array is constructed and a periphery circuit part where periphery circuits are formed in the device. The periphery circuits controls the input and output of data by applying signals to word-lines and data lines in the cell part. Since capacitors are formed to store data in the cell part, a step coverage is generated by forming the cell part and the periphery circuit part.
Accordingly, the conventional semiconductor memory device and the method of fabricating the same have the following problems.
Due to the step coverage between a cell part and a periphery circuit part, the short circuit in metal wirings is frequently occurred in the devices. Specifically, this result from the metal wirings of the cell part positioned higher than those of the periphery circuit part and insulating layers (the eighth insulating layer 29, the SOG layer 28, and the interlayer insulating layer 27) that are not precisely defined in a photolithography process. Moreover, the SOG layer exposed in a middle portion of an interlayer contact hole absorbs moisture into the interlayer contact hole and corrodes the plug layer. As a result, the electrical characteristics of the upper and lower wirings is deteriorated.

Method of fabricating semiconductor memory device


A floor covering assembly for covering the floor pan area of a vehicle in which the floor pan area includes a recess for routing an operating component, such as a wire harness, for the vehicle. The assembly includes an aesthetic material, a padding material, and a shield. The aesthetic material, such as a carpet, is adapted to be coextensive with the floor pan area to cover the floor pan area and the recess. The padding material has one side attached to the aesthetic material and is substantially coextensive therewith. The shield protects the operating component and is selectively attached to the other side of the padding material at a predetermined location smaller than the floor pan area, whereby to cover the recess in the floor pan area protectively when the assembly is installed in the vehicle to cover the floor pan aesthetically.

For many years vehicle floors have been covered with an aesthetic material such as carpet. Often, the carpet includes padding material positioned between the pile of the carpet and the floor pan over which the carpet is laid. Typically, a single piece of carpet and a single pad cover the entire interior passenger compartment of the vehicle. The floor pan may have one or more recesses or channels for routing operating components, such as hydraulic brake lines or wire harnesses. These operating components require protection from the surrounding environment by shielding the recess. For example, a wire harness routed in a floor pan recess requires electrical isolation and crush protection.
It is common practice to protect the portion of a wire harness routed in a floor pan recess with a living hinged plastic sleeve or shield substantially conforming to the cross-section of the recess. During assembly of the vehicle, an open shield is installed in a recess, a wire harness is routed inside the shield, and the shield is snapped closed. Carpet and pad is then installed over top of the floor pan and shield. While this shielding method protects the wire harness, it nevertheless has several shortcomings including high labor and material cost.


A potential which is applied to a gate electrode of a driving transistor in accordance with an emission state or a non-emission state of a light-emitting element fluctuates due to noise or leakage from a selection transistor, or the like, which causes a problem in that the driving transistor cannot turn on or off normally and malfunctions. The present invention includes a transistor connected to a light-emitting element, a power source line, a scan line, a memory circuit, and a switching circuit, in which the transistor controls light emission or non light emission of the light-emitting element, and the switching circuit controlled by the scan line conducts switching between the transistor, and the memory circuit and the power source line, and applies an input potential to the transistor.

1. Field of the Invention
The present invention relates to semiconductor devices. In particular, the present invention relates to semiconductor devices using transistors. Further, the present invention relates to display devices including the semiconductor devices, and electronic devices including the display devices.
Note that the term "semiconductor device" here includes general devices which can function by utilizing a semiconductive property.
2. Description of the Related Art
In recent years, self-luminous display devices having pixels formed with a light-emitting element such as a light-emitting diode (LED) are drawing attention. As examples of such light-emitting elements used in such self-luminous display devices, organic light-emitting diodes (also referred to as OLED (Organic Light-Emitting Diode), organic EL elements, and electroluminescence elements (also referred to as EL elements, or the like), have been drawing attention and used for EL displays or the like. Since light-emitting elements such as OLED are self-luminous type, various advantages can be provided such that high visually of pixels is ensured as compared to liquid crystal displays, no back light is required, and high response speed is achieved.
A self-luminous display device includes a display and a peripheral circuit for inputting signals to the display. By disposing a light-emitting element in each pixel of the display and controlling emission of each light-emitting element, images are displayed.
In each pixel of the display, a thin film transistor (hereinafter referred to as a TFT) is disposed. Here, a pixel configuration is described, in which two TFTs are disposed in each pixel in order to control emission of a light-emitting element in each pixel (for example, Reference 1: Japanese Published Patent Application No 2001-343933).
FIG. 15 shows a pixel configuration of a display. In a pixel portion 2100, data lines (also referred to as source signal lines) S1 to Sx, scan lines (also referred to as gate signal lines) G1 to Gy, and power source lines (also referred to as power supply lines) V1 to Vx are disposed. In addition, pixels of x (x is a natural number) columns and y (y is a natural number) rows are disposed. Each pixel includes a selection transistor (also referred to as a switching TFT, a switch transistor or a SWTFT) 2101, a driving transistor (also referred to as a driving T11) 2102, a storage capacitor 2103, and a light-emitting element 2104.
A driving method of the pixel portion 2100 is described briefly. When a scan line is selected in a selection period, the selection transistor 2101 is turned on and a potential of a data line at the time is written into a gate terminal of the driving transistor 2102 through the selection transistor 2101. In the period from termination of the selection period and to the next selection period, a potential of the gate terminal of the driving transistor 2102 is held in the storage capacitor 2103.
In the configuration of FIG. 15, when the relationship between the absolute value of a voltage between a gate and a source (|Vgs|) of the driving transistor and a threshold voltage (|Vth|) of the driving transistor 2102 satisfies |Vgs|>|Vth|, the driving transistor 2102 is turned on and a current flows by a voltage between the power source line and a counter electrode connected to the light-emitting element 2104, thereby allowing the light-emitting element 2104 to be in the emission state. Meanwhile, when |Vgs|=|Vth| is satisfied, the driving transistor 2102 is turned off and no voltage is applied to the opposite sides of the light-emitting element 2104, thereby making the light-emitting element 2104 emit no light (non-emission state).
In the pixel having the configuration of FIG. 15, two types of driving methods are generally used for expressing gray scales, which are an analog gray scale method and a digital gray scale method.
The analog gray scale method is a method for expressing gray scales by changing the luminance of a light-emitting element, using an analog signal as a signal input to each pixel. On the other hand, the digital gray scale method is a method for expressing gray scales by controlling emission or non-emission of a light-emitting element only by controlling on or off of a switching element with a signal input to each pixel.
In comparison with the analog gray scale method, the digital gray scale method is advantageous in that it is difficult to be affected by characteristic variation between TFTs, and thus gray scales can be expressed more accurately.
As an example of the digital gray scale method for expressing gray scales, there is a time gray scale method. In the time gray scale method, gray scales are expressed by controlling the emission period of each pixel of a display device. Further, by using an erasing transistor (also referred to as an erasing TFT) in addition to the driving transistor and the selection transistor in each pixel in the digital time gray scale method as disclosed in Reference 1, multi-gray scale display with high resolution can be achieved. In this specification, such a driving method is called an SES (Simultaneous Erasing Scan) drive.
In addition, in recent years, a display device having such a pixel configuration in which a memory is incorporated in each pixel of a display portion in order to reduce power consumption of the display device has been known (see Reference 2: Japanese Published Patent Application No. 2002-140034 and Reference 3: Japanese Published Patent Application No 2005-049402).
In a conventional pixel configuration disclosed in Reference 1, the power consumption of a data line driver circuit greatly depends on the charging and discharging of the last buffer. The power consumption P is generally calculated by using the following Formula (1), where F is frequency, C is capacitance, and V is voltage.P=FCV2 (F: Frequency, C: Capacitance, and V: Voltage)  (1)
According to the Formula (1), it can be seen that the voltage of a data line is preferably set to have as a small amplitude as possible by the data line driver circuit. Therefore, the voltage of a data line is set to have the minimum amplitude which allows on or off operation of the driving transistor. In other words, the absolute value of a voltage between a gate and a source (hereinafter referred to as Vgs) of the driving transistor is preferably so as to surely control the on or off operation of the driving transistor.
A potential of a data line to be input into a pixel is held in a storage capacitor in during period from termination of the selection period for turning on the selection transistor and to the next selection period for turning on the selection transistor.
However, there is such a problem that a potential that has been accumulated in the storage capacitor to be applied to the gate terminal of the driving transistor may fluctuate due to noise, leakage from the selection transistor or the like, and thus the driving transistor may malfunction without being capable of keeping the normal on or off state.
In addition, there is another problem in that the power consumption is increased if the voltage amplitude of the data line is increased in order to prevent malfunctions of the driving transistor that would be caused by fluctuation of a gate potential of the driving transistor. It can be seen from Formula (1) that the power consumption of a data line driver circuit increases in proportion to the square of a voltage; therefore, an increase in the voltage amplitude of a data line influences on the power consumption greatly.
More concretely, with reference to FIGS. 16A and 16B, problems of the conventional technique are described in detail. In the pixel configuration shown in FIG. 16A, a pixel 2200 includes a selection transistor 2201, a driving transistor 2202, a storage capacitor 2203, and a light-emitting element 2204. Note that the light-emitting element is driven with digital signals. In addition, the selection transistor is an N-channel transistor and the driving transistor is a P-channel transistor
A potential value of each wiring in FIG. 16A is described specifically. A potential of a counter electrode 2208 of the light-emitting element 2204 is GND (hereinafter, 0 V), a potential of a power source line 2207 is 7 V, a high potential level (hereinafter indicated as an High level, an High potential or High) of a data line 2206 is 7 V, a low potential level (hereinafter indicated as an Low level, an Low potential or Low) of the data line 2206 is 0 V, an High potential of a scan line 2205 is 10 V, and an Low potential of the scan line 2205 is 0 V.
Needless to say, a potential of each wiring, a polarity of each transistor and the like are just examples, and therefore, the present invention is not limited to these examples.
FIG. 16B shows a timing chart of potentials at the scan line, the data line and the node G when the light-emitting element is in the emission or non-emission state. In the period when the scan line 2205 is at 10 V, the selection transistor 2201 is turned on, and the node G receives a potential of the data line 2206. Thus, the potential of the data line 2206 is held in the storage capacitor 2203. If the potential held in the storage capacitor 2203 is the High potential, namely 7 V or higher, the voltage between the gate and source of the driving transistor 2202 becomes lower than the absolute value of the threshold voltage of the driving transistor 2202, thereby turning the driving transistor 2202 off to allow the light-emitting element 2204 to be in the non-emission state. If the potential held in the storage capacitor 2203 is the Low potential, namely 0 V or lower, the voltage between the gate and source of the driving transistor 2202 becomes higher than the absolute value of the threshold voltage of the driving transistor 2202, thereby turning the driving transistor 2202 on to allow the light-emitting element 2204 to be in the emission state.
In the pixel configuration shown herein, a potential of the data line 2206 is directly written into the node G Since the potential of the node G that is supplied from the data line 2206 controls on or off of the driving transistor 2202, at least the High potential of the data line 2206 should be equal to or higher than the potential of the power source line 2207, while the Low potential of the data line 2206 should be sufficient to turn on the driving transistor 2202. In other words, the relationship between the voltage (Vel) applied to the light-emitting element 2204 and the voltage between the source and the drain (Vds) of the driving transistor 2202 should satisfy a condition to become Vel>>Vds, which can operate the driving transistor 2202 in the linear region.
However, there is such a possibility that the potential of the node G may fluctuate due to variations or fluctuations of the threshold voltage of the driving transistor 2202, noise from outside during a holding period, a leakage potential from the selection transistor 2201 as shown in FIG. 16B, or the like, in which case the voltage between the gate and source of the driving transistor 2202 fluctuates, and thus the driving transistor 2202 may malfunction without being capable of keeping the normal on or off state.
Thus, a semiconductor device having a conventional pixel configuration has a problem in that a potential applied to the gate terminal of the driving transistor fluctuates due to noise or a leakage from the selection transistor, which causes the driving transistor to malfunction. Further, even if a signal having a large potential amplitude is supplied from a data line, which is enough to ensure the stable operation of the driving transistor, there arises another problem in that the power consumption of a data line driver circuit is increased.

Semiconductor device, display device and electronic device

Semiconductor Energy Laboratory Co., Ltd.


Example apparatus facilitate couriering (e.g., physically carrying) targeted electronic data between a provider in a first physical location and a recipient in a second physical location. An apparatus may store targeted electronic data or may store metadata concerning the targeted electronic data. The apparatus may also store requests for targeted electronic data or information from which targeted electronic data can be identified. An example apparatus may identify targeted electronic data to be provided and may then acquire the targeted electronic data from a provider. The provider may be another courier, another recipient, a source provider (e.g., database), or other source. The apparatus may provide the targeted electronic data to the recipient using a close-range communication channel that does not use the Internet. The targeted electronic data may be identified based on a state of an operating system, an application, or content at the recipient.

There are approximately 7.2 billion people in the world. There are also approximately 1.5 billion cell phones and smart phones. For many people, instant-access high-speed real-time connectivity is the norm. For billions of other people, once a day or even once a week email, social media interaction, or other "connectivity" would be revolutionary. Devices (e.g., smart phones, tablets, laptops, computers, game systems) that are able to connect to the Internet seem to be nearly ubiquitous. Whether walking the streets of New York City, hiking in the remote high Andes, trekking to parts unknown in Outer Mongolia, sitting in a coffee shop in Seattle, or taking a restful weekend in Amish country in Ohio, there is likely to be a connection enabled device nearby (e.g., in your hand). While devices are nearly ubiquitous, connectivity is not. Certainly connectivity continues to reach deeper into even the farthest corners of the world, but there are still gaps in coverage. Popular television commercials in the United States compare coverage maps for various carriers, with all the coverage maps showing significant gaps. In addition to actual gaps, where there is simply no connectivity infrastructure, gaps may be practical or economic, where connectivity is too expensive, too slow, or too insecure to be practically or economically useful.
Since devices are nearly everywhere, and since connectivity is not yet everywhere, devices that are used to communicating frequently with the Internet may be forced to function at a reduced level when connectivity is not available. While this reduced functionality may be inconvenient at times, it may be economically or even physically dangerous at others. For example, not being able to watch the most recent version of a television show may be inconvenient while not being able to receive the most recent update to a map or to receive a weather forecast may be physically dangerous. Not being able to receive the most recent security update or encryption update may be economically dangerous. Additionally, regardless of whether the reduced capability is dangerous or just annoying, the loss of connectivity reduces the utility of mobile devices.
Gaps in connectivity may be actual or may be economic or practical. An actual gap exists when there is simply no connection. The lack of connection may be temporary (e.g., network down, network overloaded, electrical blackout) or may be more systemic (e.g., lack of infrastructure). An economic or practical gap may exist even when an actual connection exists. For example, a low-speed yet high-cost connection may be available for a device. The user of the device may not want to spend an unjustifiable amount of time and money to use the low-speed high-cost connection to download a large file. However, the user of the device may be willing to spend a little time and a little money to order from a catalog of available content or to send/receive a critical message. The catalog of available content from which a user may order may even have been distributed in paper form like the old-time catalogues from department stores. In this case, delivery of digital content through an existing though impractical link may not be desired, even if an order can be placed through the impractical link.


An automatic pump-based fluid management system, as described herein, comprises an intercostal pump that is, generally, a resiliently flexible bulb having an inlet and an outlet. The inlet is attached to a first tube that extends from the intercostal pump to a first area of a patient's body, for example, the patient's pleural cavity. The outlet is connected to a second tube that extends from the intercostal pump to a second area of a patient's body, for example, the patient's peritoneal cavity. In use, the intercostal pump is placed between a first rib and a second rib in a patient. The intercostal pump operates by being successively compressed and decompressed between the first and second ribs as the patient breaths.

A number of techniques for draining bodily fluid involve utilizing a pump, in combination with a shunt or catheter, to drain fluid from one cavity within the human body to either another cavity or to a reservoir outside of the body. Such techniques may be utilized for purposes including, for example, draining a patient's blood, urine, saliva, cerebrospinal fluid, peritoneal fluid, and/or pleural fluid, among other possibilities.
One drainage-technique application is the drainage of pleural fluid for the treatment of pleural effusions. Pleural fluid is normally a low-protein liquid that can be found in relatively small amounts (normally 10-20 milliliters) in each of a patient's pleural cavities. The pleural cavities are the spaces between the visceral pleura (i.e., the membrane located over the entire outer surface of each lung) and the parietal pleura (i.e., the membrane lining the inside of the chest wall of each hemithorax). The small amount of pleural fluid in each pleural space is spread out very thinly between the visceral and parietal pleura thereby providing for a large surface tension which mechanically couples the lung to the chest wall while simultaneously lubricating these surfaces allowing the lung to slide over the chest wall during the breathing process. In a normal, healthy person, pleural fluid is constantly being produced, largely from leakage of fluid from blood and lymphatic vessels in the visceral pleura that coats the outer surface of the lung and reabsorbed at essentially the same rate by lymphatic channels located in the parietal pleural that lines the chest wall. This dynamic balance exchanges the fluid multiple times a day and maintains a low total volume in the 10-20 milliliter range. However, under certain abnormal conditions, such as infection, inflammation, malignancy, heart failure, liver failure, or kidney failure, among other conditions, the net flow of pleural fluid within the pleural cavity becomes unbalanced, with increased fluid production, decreased reabsorption, or both, resulting in the excess accumulation (e.g., on the order several hundred milliliters to several liters) of fluid in the pleural space.
Excess accumulation of pleural fluid is known as pleural effusion and adds additional mass that must be moved with each breath and may cause the pathological compression of lung tissue. This results in considerable difficulty in or prevention of the breathing process. Pleural effusion may lead to, for example, dyspnea, shortness of breath, chest pain, and/or chronic cough, and may greatly compromise a patient's quality of life.
Currently, pleural effusions affect approximately 1.5 million new patients each year in the United States. Many of these effusions are chronic, recur if drained, and can be quite symptomatic and debilitating for the patient. One common type of recurrent, symptomatic pleural effusion is the result of malignancy. Over 200,000 malignant pleural effusions occur each year in the United States and more than one half of those patients with malignant pleural effusions have recurrent symptoms resulting directly from their effusion.
Treatment options for recurrent, symptomatic pleural effusions can be divided into 1) repeated drainage of the pleural effusion and 2) elimination of the pleural space.
One approach to the treatment of recurrent, symptomatic pleural effusions, is repeated therapeutic thoracentesis. Thoracentesis involves passing a needle and catheter apparatus into the pleural cavity, at which point the needle is removed, leaving the catheter in the pleural space. The catheter remains in place and, thereby, acts as a drainage tube that allows the excess pleural fluid to be moved from the pleural space to a collection reservoir outside of the body. This procedure typically improves symptoms significantly. Unfortunately, malignant effusions are likely to recur following drainage and in order to control symptoms therapeutic thoracentesis must be repeated frequently. However, due to patients' delays in notifying their physician that their symptoms have returned and delays in organizing and providing repeat thoracentesis, patients often spend a significant portion of their life with effusion-related symptoms. Furthermore, thoracentesis is painful and uncomfortable, and is frequently accompanied by complications such as pneumothorax (i.e., the collapse of the lung due to accumulation of air in the pleural cavity) in up to eleven percent of patients and severe bleeding or infection in many others.
Another treatment option is pleurodesis. Pleurodesis is the obliteration of the pleural space and adhesion of the visceral and parietal pleural surfaces by the instillation of a sclerosant agent into the pleural space. In one approach, the sclerosant agent is introduced via a chest tube that has been inserted into the patient under moderate sedation or general anesthesia for drainage of the pleural fluid in a manner similar to the drainage achieved in thoracentesis. After drainage of the pleural effusion a sclerosing agent is instilled through the tube into the pleural cavity to completely coat the visceral and parietal membranes so that these membranes will permanently adhere to each other to close and eliminate the pleural cavity. Chest-tube pleurodesis can sometimes lead to long-term control of effusion-related symptoms. Unfortunately, chest-tube pleurodesis typically requires hospitalization for at least two days and as many as seven days, can be quite painful, can lead to breathing difficulties related to the pleurodesis, and, in up to one third of patients, fails to provide relief of symptoms for more than a few weeks.
Another variation of pleurodesis is thoracoscopic pleurodesis, which involves the insertion of a telescope into the patient's chest by way of an intercostal incision on the patient's side. Pleural fluid is evacuated, and a detailed inspection of the pleural space is undertaken so as to more discriminately apply sclerosant to regions of abnormality. In some cases, thoracoscopic pleurodesis can achieve better results than chest-tube pleurodesis. Unfortunately, thoracoscopic pleurodesis typically still requires prolonged hospitalization for four to seven days, can also be quite painful, can lead to breathing difficulties related to the pleurodesis, and, in many patients, fails to provide relief of symptoms for more than a few weeks.
Yet another treatment option is chronic indwelling pleural catheters. Such indwelling catheters are placed in the patient permanently, allowing a patient to drain pleural fluid to an external reservoir on an intermittent, yet continual, basis. That is, the pleural catheter is placed with one end in the affected pleural space inside the patient's body and the other end of the catheter extends outside of the patient's body and remains externally exposed for extended period of times. Chronic indwelling catheters have been shown to result in relatively high success rates in the management of effusion-related symptoms and are associated with relatively short patient-hospital times of approximately one day. However, because the catheter passes through the patient's skin with a portion inside the body and a portion outside the body, a considerable fraction of patients, approximately eight percent, fall victim to infection. Further, the patient is subject to the discomfort, irritation, and annoyance of an exposed indwelling catheter. Finally, in order to gain relief from effusion related symptoms, the patient or their caregiver must actively access the external portion of the catheter, connect the catheter to an external reservoir, and drain effusion fluid from the pleural space into the reservoir.
Still another approach are pleuroperitoneal shunts. Pleuroperitoneal shunts provide a permanent conduit between the pleural cavity and the peritoneal cavity, or the abdomen, which allows fluid to move from the pleural cavity to the peritoneal cavity, as opposed to an external reservoir. Once in the peritoneal cavity, the fluid is reabsorbed into the patient's blood stream through blood and lymph vessels located in the abdomen. In popular pleuroperitoneal shunts, the shunt has a pumping chamber that must be manually activated by the patient or caregiver to move the pleural fluid. The pleuroperitoneal shunt is tunneled under the skin from the chest to the abdomen with the pumping chamber lodged in a subcutaneous pocket overlying the rib cage. Pleuroperitoneal shunts, like chronic indwelling catheters, have been shown to result in relatively high success rates in the management of effusion-related symptoms and are associated with relatively short patient-hospital times of approximately one day. However, also like chronic indwelling catheters, a considerable percentage of patients, approximately four percent, fall victim to infection. Further drawbacks of conventional pleuroperitoneal shunts include a relatively high rate of shunt-specific complications, such as clotting of fluid within the shunt. Finally, in order to gain relief from effusion related symptoms, the patient or their caregiver must actively compress the pumping chamber multiple repeatedly to transfer effusion fluid from the pleural space to the peritoneal space causing significant discomfort and inconvenience.
Other drainage-technique applications exist. These include, but are not limited to, drainage of pericardial fluid, cerebrospinal fluid, peritoneal fluid, urine, bile, and lymph. Cavities into which such fluids can be drained include, but are not limited to, the pleural space, the peritoneal space, the bile duct, the stomach, lymphatic vessels including the thoracic duct, veins including the vena cava, and the bladder.
The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventor, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.


A method for playing team chess has been devised by using a modified chess board and using conventional chess rules. The gameboard has a square matrix of fourteen squares by fourteen squares. Four sets of conventional chess pieces are used, each set containing one king, one queen, two bishops, two knights, two rooks, and eight pawns. Each set of chess pieces differ in color, with two sets of pieces having light colors representing one team and two sets of chess pieces having dark colors representing the other team. The chess pieces move according to the conventional rules of chess. Each player's king must be checkmated two times by the opposing players before the player is removed from the game. A player in checkmate remains in checkmate and is unable to move any of his/her playing pieces during the player's subsequent turns until either his partner blocks the checkmating piece, or his partner captures the checkmating piece, or one of the opposing players moves one of the opposing playing pieces into a position so that the checkmate is removed. Playing pieces of the removed player remain on the board cannot be moved for the remainder of the game and can only be removed when captured.

1. Field of the invention
This invention relates to the conventional game of chess and is exclusively a game variated from the original version in order for participants to play team chess, two partners against two partners. Since chess has been around for centuries, it is probably the most popular and strategically developed board game, but it is limited to two players. Although chess is such a great game within itself, a modified game for team chess will circulate more interest in conventional chess as well as contribute to family enjoyment. This invention will also give avid chess players the opportunity to pursue a much more defined challenge outside conventional chess.
2. Description of Prior Art
Chess has been around for ages and although there have been attempts to alter the game for more than two persons, none have really been accepted by the public, evidence being that none of these games have actually hit big on the market. The alterations of these said revised games vary from drastic changes and complications in the rules of conventional chess to radical alteration of the playing board. Games have been submitted for three and four person play, but no one game is exclusively partner play, that is, team chess. This invention is relatively simple and easy for just about anyone to understand. Conventional chess is sophisticated enough without making numerous changes which may easily confuse a beginner. There is a need for another game that is mentally challenging, a game that meets all logical specifications for partner chess, yet will remain simple for anyone to enjoy.