Blade applicator assemblies for resurfacing apparatus are provided for mounting forwardly and rearwardly of the apparatus frame. Each forward and rearward blade applicator assembly comprises an elongated base member, and an elongated blade assembly mounted to the base member. The rearward blade applicator assembly also includes an elongated roller extending rearwardly from the base member.

This invention relates to a novel applicator blade assembly for use with a resurfacing machine of the type described in my earlier U.S. Pat. Nos. 4,906,126 and 4,917,533, both of which are expressly incorporated herein by reference. The machines as described in the above mentioned patents, as well as in a third prior patent, i.e., U.S. Pat. No. 4,789,265, were designed for resurfacing tennis courts, parking lots, warehouse floors and the like. A significant aspect of these prior machines is the incorporation of free-floating forward and rearward applicators for smoothing and spreading the acrylic composition. The forward applicator in one embodiment of my prior machine was provided with a leading squeegee type blade and a trailing brush, while the rearward applicator was provided with leading and trailing brushes. The applicators as described in my prior patents are particularly beneficial when applying coating material (such as acrylic) of relatively low viscosity and in relatively thin layers, e.g. 12-15 mils. There remained a need, however, for an applicator assembly which would reliably and uniformly distribute thicker coating material including cementitious materials as typically used in parking lot applications, for example.
The blade applicator assembly in accordance with this invention has been found to be particularly useful with thicker coating material (up to 150 mils or more) of greater viscosity, and including cementitious materials. The blade applicator assembly of this invention may be mounted on my prior machine in the same manner as (and are interchangeable with) the forward and rearward applicators described in my above identified prior patents. For applications such as multi-coat systems for parking lots, the applicator assemblies of my prior patents and the blade applicator assembly disclosed herein may be selectively used to apply the various components of the multi-coat system as will be described in greater detail herein.
In accordance with an exemplary embodiment of the invention, the blade applicator assembly, which is designed for use as both forward and rearward applicators, includes an elongated, channel member or beam which supports a plurality of squeegee blades, aligned end-to-end, from one end of the base member to the other. At the interface between adjacent blades, a (rubber) squeegee flap is employed to cover the interface gap or seam to thereby prevent coating material from passing between adjacent vertical edges of the respective squeegee blades. The lower edges of the aligned blades are notched, with openings varying in size depending on the thickness of the coating to be applied.
The blades are sandwiched between rigid plates which, in turn, are attached to the channel member or beam by means of a plurality of spring loaded rods, enabling the blades to individually self-adjust in a vertical direction as the machine travels over uneven floors.
In another aspect of the invention, an elongated roller bar is pivotally secured to the channel member, extending rearwardly therefrom, and adapted to roll the coating previously uniformly distributed by the forward, notched squeegee blades. The roller bar is designed to receive interchangeable roller covers, the selection of which depends on the coating material applied. The roller serves to apply a final surface texture to the coating material, and to remove any air bubbles (i.e., aerate) present in the material, and as such, is secured to the rearward applicator assembly only.
Another feature of the invention relates to the utilization of vertically oriented end blades extending perpendicularly with respect to the spring loaded squeegee blades, on both forward and rearward applicator assemblies. These end blades, which may be laterally adjustable, extend forwardly from opposite ends of the applicator, and are mounted for self-adjusting up and down movement as determined by floor surface and gravity. These end blades serve to confine the coating material within the area defined by the applicator assembly per se.
Accordingly, the present invention in its broader aspects relates to a resurfacing apparatus for distribution and smoothing of a predetermined thickness of coating material on a surface, the apparatus comprising at least one applicator assembly having first means for spreading the material uniformly over the surface at the predetermined thickness, and second means for texturing and aerating the material, the first means located forward of the second means relative to a direction of travel of the resurfacing apparatus.
In another aspect, the present invention relates to a resurfacing apparatus comprising a central frame supported by a plurality of wheels; a plurality of support arms extending forwardly and rearwardly of the central frame; a forward blade applicator assembly secured to the support arms extending forwardly of the central frame; a rearward blade applicator assembly secured to the support arms extending rearwardly of the central frame; wherein each of the forward and rearward blade applicator assemblies comprises an elongated base member and an elongated blade assembly mounted to the base member, and further wherein the trailing blade applicator assembly includes an elongated roller extending rearwardly from the elongated base member.
The above described blade applicator assemblies may be formed in desired lengths, as dictated by the machine length, and the area to be resurfaced. The have significant advantages in that, by the judicious selection of blade notch size and roller cover nap, coatings of various thicknesses up to about 150 mils may be applied in a uniform and attractive manner with extensive savings in both time and cost. Moreover, these blade applicator assemblies may be used in combination with the applicator assemblies of my prior patents for application of complex, multi-coat resurfacing systems.
Additional objects and advantages of the present invention will become apparent from the detailed description which follows.

Applicator blade assembly for resurfacing apparatus


In a battery pack, it is difficult that information on a contained battery of the battery pack, such as the accurate state of charge of the battery, is detected at an external equipment. A communication terminal which can communicate the state of charge of the contained battery to the external equipment is provided on the installation surface on which power supply terminals of the battery pack are provided or on the surface adjacent to the installation surface. This allows the corresponding electrodes or the like of the external equipment to be concentrated at one place, so that the space required to arrange the corresponding electrodes or the like is reduced, thus downsizing the equipment.

1. Field of the Invention
This invention relates to a battery pack, and more particularly, is applicable to a battery pack which supplies DC power to electric equipment.
2. Description of the Related Art
Today, many battery packs are commercially available, which contain one or more batteries to supply DC power to portable electronic equipment. A wide variety of battery packs, including those which are rechargeable or are not rechargeable and those which have their specific applications, are on the market. Electronic equipment therefore is likely to be loaded with inappropriate battery packs, thus causing the malfunction of the equipment or damage thereto. A mechanism that is intended to prevent an inappropriate battery pack from being accidentally loaded into electronic equipment is incorporated in battery packs. As an example, a battery pack for a videotape recorder with a camera is shown in FIGS. 1 and 2A to 2C. FIGS. 2A, 2B, and 2C are a plan view, a side view, and a bottom view of the battery pack, respectively.
The battery pack 1 comprises a case 4 consisting of an upper case 2 and a lower case 3, which are provided with a fitting mechanism to prevent the loading of an inappropriate battery pack. A groove 2A on top of the upper case 2 is for preventing the battery pack from being inserted into equipment in an incorrect direction. The battery pack is designed so that if the battery pack is by accident inserted into equipment in an opposite direction, a part of the upper case 2 that is not grooved rests against a guide rail in the equipment to prevent the battery pack from being inserted into the equipment.
On the other hand, the lower case 3 is provided with concave portions 4, 5, 6, and 7 along the center line X--X and with a concave portion 8 along a side wall. The concave portions 5 and 8 are detection holes, and the concave portion 6 is a locking hole used to install the battery pack to electronic equipment of external battery installation type. More specially, the concave portion 4 is a spare detection hole and a detection hole indicating that the battery pack 1 contains a lithium ion battery, respectively. The concave portion 8 is a detection hole indicating that the battery pack 1 is rechargeable.
The lower case 3 is also provided at the sides and bottom thereof with grooves 9A, 9B, 10A, and 10B to install the battery pack to electronic equipment of external battery installation type. A marker 13 indicating the state of charge of the battery, which marker is installed on the side of the lower case 3 on which power supply terminals 11 and 12 are provided, allows it to be determined whether the battery pack 1 is fully charged or depleted.
As described above, a conventional battery pack is designed so that it can be determined, by seeing whether or not convex portions fit into corresponding detection holes, whether or not the battery pack is attachable to electronic equipment or a charger.
In these days electronic equipment has been required to perform more and more functions and provide more accurate information. Such information includes the state of charge of the battery and output current amperage.


An epitaxial growth method for a compound semiconductor thin film, capable of forming a p-n junction with an atomic-scale ultra-micro structure is disclosed. The method involves loading the compound semiconductor substrate in a reaction chamber, injecting Group V and III metal organic source gases not processed by a thermal pre-decomposition process into the reaction chamber, and growing a p- or n-type compound semiconductor on the compound semiconductor substrate while adjusting the growth temperature of the p- or n-type compound semiconductor.

1. Field of the Invention
The present invention relates to an epitaxial growth method for compound semiconductor thin films, and more particularly to an epitaxial growth method for a compound semiconductor thin film, capable of forming a p-n junction by control of growth temperature.
2. Description of the Prior Art
Recently, growth of semiconductors with a hetero-junction structure, in particular, compound semiconductors, has been widely used by virtue of the development of thin film growth techniques and equipment and the development of molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) methods. Also, semiconductor devices using hetero-junction structures made of a variety of compound semiconductors have been widely used.
In the growth of such structures over a semiconductor substrate, it is necessary to grow a layer containing an n or p type impurity on a semiconductor substrate. By the growth of such a doped layer, a p-n junction structure, which is a heterojunction structure between p type layer and n type layer to be grown on the substrate, is formed. Such a hetero- junction structure has been widely used.
In this connection, the adjustment of the concentration of the impurity contained in the doped layer and the adjustment of the conductivity-type of the doped layer are important factors for determining the characteristic of the final semiconductor device. In this regard, it is known that the development of doping processes is commercially and technically important.
Recently, heterojunction bipolar transistors (HBTs) using III-V compound semiconductors have been getting popular by virtue of their superior characteristics expected in high-speed devices. In particular, the epitaxy of InGaAs with p type carriers is an important technique in the fabrication of InGaAs/InP heterojunction bipolar transistors.
In order to realize such heterojunction bipolar transistors operating at a high speed, a reduced base resistance should be used. To this end, a very large amount of impurity should be doped in the base layer of a transistor structure in the fabrication of the transistor structure.
However, beryllium (Be) or zinc (Zn) conventionally used as a p type impurity exhibits a very large diffusion coefficient at a high doping concentration. In this case, the performance of the semiconductor device is degraded.
In order to overcome such a problem, research on doping of a carbon impurity in an InGaAs is being made. Such a carbon impurity has superior characteristics in that it exhibits a low diffusion coefficient upon the growth of a GaAs and a high doping concentration.
Generally, the carbon impurity is known to have an n type conductivity in InGaAs. As a result of such research, it is also known that it is impossible to grow InGaAs with p type carriers using metalorganic compounds as a Group III source material. It is also known that such a p type InGaAs can be formed only when a source impurity material such as carbon tetrachloride (CCl.sub.4) is additionally supplied. Recently, it has also been reported that the p type InGaAs can be grown only when solid indium is used as a source material for providing indium (Reference: T. P. Chin et al, Highly Carbon-Doped P-Type GaInAs and GaInP by Carbon Tetrachloride in Gas Source Molecular beam Epitaxy, Appl. Phys. Lett., 59:2865, 1991).
Thus, the conventional techniques have a problem in that two different doping processes are required to form a p-n junction structure of InGaAs.

Formation of InGaSa p-n Junction by control of growth temperature

Electronics and Telecommunications Research Institute


An engine or like apparatus includes a linear-to-rotational motion converting mechanism which emulates an elliptic trammel or ellipsogragh linkage. The apparatus includes at least one cylinder disposed along a first axis and a piston reciprocable in the at least one cylinder along the first axis. Also included is an orbital crankshaft having a piston crank and an orbital shaft, the piston crank having a first end journaled to the piston and a second end, the second end being secured to the orbital shaft, the orbital shaft extending along a second axis perpendicular to the first axis. An output crank has a first end and a second end, the first end of the output crank being journaled to the orbital shaft. An output shaft is secured to the second end of the output crank, the output shaft being rotatable at an angular velocity about a third axis parallel with the second axis and perpendicular to and intersecting the first axis. A timing unit is coupled to the orbital shaft, the timing unit constraining the orbital shaft to rotate about the second axis at an angular velocity equal and opposite to that of the angular velocity of the output shaft. The timing unit includes an epicyclic gear train having one or, preferably, two stages.

1. Field of the Invention
The present invention relates to internal combustion engines and like apparatus which includes a mechanism for converting the reciprocating motion of one or more pistons into rotational motion of an output element, and in which the motion converting mechanism emulates an elliptic trammel type or "ellipsograph" linkage.
2. Description of the Prior Art
As is well known, conventional internal combustion engines utilize piston rod and crank mechanisms for converting the reciprocating motion of the pistons into rotational motion of an output shaft. Such conventional mechanisms have certain drawbacks. For example, the piston and cylinder wall surfaces wear substantially as a result of side thrust forces. These side forces may also cause significant power losses due to friction. Piston/cylinder mismatches may also cause jamming of the pistons. Moreover, these conventional engines often lack appropriate balancing means, so that non-balanced, secondary inertial forces constrain the angular velocity of the output shaft thereby limiting increases in power output. Still further, conventional crankshafts tend to be massive, reflecting the strength that is built into them in order to handle full output torque. Durability is sometimes compromised because of insufficient lubrication of the pistons working in a high-temperature environment.
A known alternative to the conventional piston rod and crank internal combustion engine (ICE) utilizes an elliptic trammel linkage, or "ellipsograph" mechanism for converting the reciprocating motion of the pistons into rotational motion of an output shaft. An improved version of an ICE incorporating such a mechanism is disclosed in U.S. Pat. No. 5,189,994 issued Mar. 2, 1993 and incorporated herein by reference. FIG. 1 of the prior art '994 patent, which figure has been reproduced as FIG. 1 herein, shows a two-dimensional schematic representation of an engine 10 employing the "ellipsograph" principle. The engine 10 includes an engine block or casing 12 carrying a crankshaft bearing 14. The casing 12 defines a horizontal cylinder 16 and a vertical cylinder 18 disposed orthogonally relative to each other along an X axis and a Y axis, respectively. The cylinders 16 and 18 are provided with intake and exhaust valves 19. Pistons 20 and 22 are received for reciprocation within the cylinders 16 and 18, respectively. A connecting rod 24 couples the piston 20 with a horizontal guide in the form of a slide 26 movable within a linear guideway 28 aligned with the X axis; similarly, a connecting rod 30 couples the piston 22 with a vertical guide in the form of a slide 32 movable within a linear guideway 34 disposed along the Y axis. A link or orbital crankshaft 36 connects the slides 26 and 32 at end points 38 and 40. Last, a power output crank 42 having one end connected to the midpoint 44 of the orbital crankshaft 36 and its other end journaled in the bearing 14, is rotatable about a central point 46 lying on a longitudinal Z axis mutually orthogonal to the X and Y axes. It will be evident that the two-dimensional mechanism of FIG. 1 is theoretical only; for example, the intersecting guideways 28 and 34 would preclude realization of a practical engine which would require that the guideways be offset along the Z axis.
In the operation of the engine shown schematically in prior art FIG. 1, as the pistons 20 and 22 reciprocate in their respective cylinders and with the pistons alternately reaching their top and bottom dead centers, the ends 38 and 40 of the orbital crankshaft reciprocate between their horizontal and vertical endpoints equidistant from the Z axis represented by the point 46. The output crank 42 is thereby driven with an angular velocity, .omega., with the point 44 describing a circle centered on the Z axis. At the same time, the orthogonally disposed, linear slides and guides together with the crank 42, constrain the orbital crankshaft 36 to counterrotate at an angular velocity of -.omega. about an axis passing through the point 44.
As explained in the '994 patent, IC engines employing the principles of that patent have significant advantages. Nevertheless, the slide/guide arrangement disclosed in the '994 patent has been found to have several drawbacks. For example:
(a) the alignment requirements imposed by the slide/guide arrangement result in difficulties in packaging the engine crankcase; PA1 (b) significant side loads produced within the slide-guide mechanisms result in friction losses, especially at high rpm, approaching those encountered in conventional piston/crank IC engines; PA1 (c) pressurized lubrication of the slide/guide arrangement requires a high capacity, high pressure oil pump that is costly and consumes substantial power and it is moreover difficult to retain sufficient oil within the fast moving slide/guide mechanism to adequately lubricate that mechanism; and PA1 (d) the mass of the reciprocating slide-guide mechanisms is substantial and precludes reducing the total mass of the moving parts to below that of conventional IC engines.
Thus, although relatively slow, large engines such as those used for marine applications may successfully use the principles of the '994 patent, the foregoing drawbacks render ICEs employing the slide/guide arrangement of the '994 patent uncompetitive with present high rpm conventional engines used, for example, to power passenger vehicles.
Accordingly, it is an overall object of the present invention to provide an ICE or like apparatus that eliminates dependency on the slide/guide arrangement of known elliptic trammel type linkages while preserving the benefits of such mechanisms.

Internal combustion engine with improved orbital crankshaft motion converter


A microfluidic printing apparatus for transferring ink to a receiver includes at least one ink reservoir; a structure defining a plurality of chambers arranged so that the chambers form an array with each chamber being arranged to form an ink pixel; a plurality of microchannels connecting the reservoir to a chamber; and a plurality of microfluidic pumps each being associated with a single microchannel for supplying ink from an ink reservoir through a microchannel for delivery to a particular chamber. Air is delivered to isolate ink in the chamber so that a predetermined amount of ink in the chamber can be transferred to a receiver, and the microfluidic pumps are operated for delivering the predetermined amount of ink to each chamber.

Microfluidic pumping and dispensing of liquid chemical reagents is the subject of three U.S. Pat. Nos. 5,585,069, 5,593,838, and 5,603,351, all assigned to the David Sarnoff Research Center, Inc. The system uses an array of micron sized reservoirs, with connecting microchannels and reaction cells etched into a substrate. Electrokinetic pumps comprising electrically activated electrodes within the capillary microchannels provide the propulsive forces to move the liquid reagents within the system. The electrokinetic pump, which is also known as an electroosmotic pump, has been disclosed by Dasgupta et al., see "Electroosmosis: A Reliable Fluid Propulsion System for Flow Injection Analysis", Anal. Chem. 66, pp 1792-1798 (1994). The chemical reagent solutions are pumped from a reservoir, mixed in controlled amounts, and them pumped into a bottom array of reaction cells. The array may be decoupled from the assembly and removed for incubation or analysis. When used as a printing device, the chemical reagent solutions are replaced by dispersions of cyan, magenta, and yellow pigment, and the array of reaction cells may be considered a viewable display of picture elements, or pixels, comprising mixtures of pigments having the hue of the pixel in the original scene. When contacted with paper, the capillary force of the paper fibers pulls the dye from the cells and holds it in the paper, thus producing a paper print, or photograph, of the original scene. One problem with this kind of printer is the accurate control of the print density. The problem comes about because the capillary force of the paper fibers is strong enough to remove all the ink from the device, draining it empty. If the paper is not removed from contact with the ink cells at the correct time, the print density will be too high or too low. Moreover, the correct paper contact time varies with the ambient temperature, making the timing problem more difficult. One solution to this problem is given in the above mentioned copending application entitled "Microfluidic Printing on Receiver", where a special paper is employed which will absorb only a limited amount of ink. It would be desirable to employ plain paper for this kind of printing.

Air isolation of ink segments by microfluidic printing


Disclosed is a polymer electrolyte membrane (PEM) fuel cell assembly apparatus for receiving an inserted membrane electrode assembly (MEA). The apparatus includes modular features for connecting a plurality of fuel cells into a planar fuel cell xe2x80x9cstackxe2x80x9d capable of using ambient air to supply oxidant gas and dissipate heat and water vapor. The invention also facilitates convenient removal and replacement of individual cells or MEAs in a stack without disassembly of the entire stack.

This invention relates to Polymer Electrolyte Membrane (PEM) fuel cells and, in particular, to modular PEM fuel cells designed for assembly into fuel cell stacks. Additionally, the invention relates to fuel stack apparatus and methods with improved maintenance, scalability, and heat dissipation characteristics.
Generally, fuel cells for the production of electrical energy from a fuel and oxidant are known in the art. In a fuel cell, electric power and water vapor (as a by-product) are produced when fluid hydrogen and oxygen, usually in the form of gases, provided to anode and cathode electrodes respectively, react through an electrolyte. Electric power produced is then collected by the lead lines. Essentially, the reaction is an oxidation of the fuel, but the method results in direct production of electrical energy, with heat energy being produced as a side effect. As an alternative to hydrogen gas, other fuels containing hydrogen may be used.
A good deal of concern in the art is directed to methods of stacking unit fuel cells in order to increase overall voltage output. A single cell, depending on design and application, may provide 0.3-1.5 volts output. Most battery replacement applications, for example, require 1.5-24 volts or more output voltage. The favored approach to increase voltage from that provided by a single cell is to physically stack a plurality of unit cell structures. This is commonly done with a sequentially stacked first gas diffusion layer, an anode electrode film, an electrolyte layer, a cathode electrode film, a second gas diffusion layer, and a bipolar connecting plate. The unit cells are electrically connected in series by means of conductive end plates. Generally, one end plate contacts the anode electrode of a first unit cell on one side of the stack, and another end plate contacts the cathode electrode of a last unit cell on the opposite side of the stack, with any number of similar cells stacked between.
In operation, hydrogen gas or other fuel is provided in the anode side of the fuel cell body, oxygen gas as oxidant is provided in the cathode side. The hydrogen and oxygen then react, producing a useful electric current, and water vapor as a by-product. The electrolyte can be a solid, a molten paste, a freeflowing liquid, or a liquid trapped in a matrix. The solid type of electrolyte, or Polymer Electrolyte Membrane (PEM), is well known in the art.
In the construction of fuel cells, several tradeoffs are made in order to optimize overall function in light of problems with the existing state of the art. Most currently known PEM fuel cells use a construction technique which incorporates the functions of anode electrode film, electrolyte, and cathode electrode film into a single unit, called a Membrane Electrode Assembly (MEA). This has the advantage of making assembly of stacked fuel cells more convenient. The conventional Gas Diffusion Assembly (GDA) provides for routing of gases to the MEA, and also for electrical contact with the MEA.
In the conventional PEM fuel cell stack of conventional unit fuel cells, a compressive force is applied to the end plates. This is transferred as a distributed force to the individual members of the stack. There may be many individual members of the stack, depending on the desired voltage output. For instance, if a single unit cell provided 0.6 volts, and a total of 24 volts output were desired, then there would be 40 unit cells in the total stack. A number of problems can occur as a consequence of this reliance on a distributed applied force to squeeze the stack together.
One such problem is that during operation, the membrane included in each MEA changes volume depending on both operating temperature and degree of hydration. The degree of hydration varies depending on operating circumstances. During the chemical reaction in the fuel cell, water vapor is produced as a by-product. This water vapor may back-diffuse from the cathode through the electrolyte, resulting in a substantial volume change in the electrolyte. In fact, the water cannot be completely eliminated, but rather, its presence in the electrolyte layer is helpful in maintaining high protonic conductivity. Therefore, the fuel cell design must accommodate substantial volume change of the electrolyte layer.
There exist tradeoffs between the need to accommodate swelling of the electrolyte layer, and the need for good electrical contact and fluid sealing. In the fuel cell stack design, a certain amount of compression is provided in order to ensure good electrical contact between adjacent unit fuel cell structures, as well as to maintain sealing of the fuel and oxidant fluids. As the volume change occurs, the effective xe2x80x9csqueezexe2x80x9d or compressive pressure applied will vary. For a large number of stacked unit cells, the variation in distributed squeeze pressure can be pronounced. When squeeze pressure varies on the low side, then either leakage of supply fluids can occur, or electrical contacting resistance can increase. Both result in a loss of energy efficiency. When squeeze pressure varies on the high side, then catastrophic damage to one or more unit cells can result. Repair involves complete disassembly of the stack, troubleshooting to locate the damaged unit cells, replacement of damaged unit cells, and re-assembly of the stack. Such repairs can be quite costly, and add significantly to the life-cycle costs of the fuel cell stack.
Conventional approaches to fuel cell stack construction include systems for dissipating excess heat. A significant portion of the available energy output of a fuel cell stack can in fact be diverted to cooling fans or compressors in order to handle the heat load. In fact, fuel cell stack applications can be limited by the requirement to dissipate waste heat. Either power output must be reduced in order to prevent uncontrolled heat buildup, or a cooling system must be provided. A cooling system carries the serious disadvantages of cost, size, complexity, and loss of overall system thermodynamic efficiency.
There is a need for fuel cells designed for creating fuel cell stacks which overcome these problems, particularly in portable applications.
A Polymer Electrolyte Membrane (PEM) fuel cell assembly apparatus has a membrane electrode assembly (MEA). The apparatus has a body with a cavity for receiving the MEA and conductive elastomeric seals. The seals divide and hermetically separate the body cavity into a cathode chamber and an anode chamber. A fuel port is provided in the body for conducting fuel into the anode chamber. The cathode chamber is exposed to a source of oxygen. An integral connector included in the body provides an electrical path between the anode chamber and the outside of the body. An anode conductor provides an electrical path between the anode surface and the integral connector. A cathode conductor provides an electrical path between the cathode surface and an external connector, which extends outside of the body. In the preferred embodiment, a lid is provided for completing assembly and for maintaining compression of the components to maintain hermetic sealing and good electrical connections. The apparatus includes modular features for connecting a plurality of fuel cells into a fuel cell stack, and for facilitating removal and replacement of individual cells or MEAs in a stack. The fuel cell and stack are designed for inherent heat dissipation characteristics.
According to another aspect of the invention, individual fuel cell assemblies are incorporated into one integrated stack unit having multiple cavities. The integrated stack units are themselves stackable.
According to yet another aspect of the invention, a fuel cell stack with individual fuel cells has lids incorporated in one integrated unit having multiple apertures.
According to still another aspect of the invention, a fuel cell has snap connectors for mechanically and electrically coupling the fuel cell to one or more additional fuel cell to form a modular fuel cell stack.
The present inventions offer definite advantages over conventional systems and methods, particularly in terms of scalability, modularity, and the ease of configuring fuel cell stacks for particular voltage, size, shape, and heat dissipation characteristics according to the desired application.

Modular polymer electrolyte membrane unit fuel cell assembly and fuel cell stack


There is provided an electrode material for electrolytic capacitor that attains an unprecedentedly high capacitance. The electrode material for electrolytic capacitor comprises a layer of valve metal particles furnished on the surface thereof with an oxide film, the layer having a porosity of 20 to 60% and a specific surface area of 30×103 to 400×103 cm2/cm3, wherein the valve metal particles are mixed together, with the particle diameters exhibiting a given distribution at least within the range of 0.005 to 0.1 μm, and form a base material surface, and wherein the valve metal consists of aluminum, and wherein the composition ratio of Al/O of the layer of valve metal particles furnished on the surface thereof with the oxide film is within the range of 2.0 to 5.5. The electrode material thus realizes high capacitance.

1. Field of the Invention
The present invention relates to an electrode material for an electrolytic capacitor, and more particularly, to an electrode material for an electrolytic capacitor having unprecedentedly high capacitance properties.
2. Description of the Related Art
Recent smaller and higher-reliability electronic devices strongly demands the smaller size and the higher capacity of an electrolytic capacitor.
An electrolytic capacitor typically has such a structure in which a capacitor element is formed by am anode electrode foil and a cathode electrode foil, wound together with an intervening separator made of manila paper and the like; the anode electrode foil is made of a band-shaped high purity aluminum foil, wherein the effective aluminum foil surface is enlarged through a chemical or electrochemical etching process, and wherein an oxide film is formed on the surface through a chemical process of treating the aluminum foil with chemical solution such as adipic acid ammonium solution and the like; while the cathode electrode foil is made of a high-purity aluminum foil that is subjected only to an etching treatment. Next, the capacitor element, after impregnating with electrolyte solution for driving the electrolytic capacitor, is housed into a bottomed outer case comprising aluminum. The outer case is equipped at the opening with a sealing member comprising an elastic rubber, and is sealed by drawing.
Development of an etching technique is conducted with respect to this type of an aluminum electrolytic capacitor, wherein, aiming to enhance the capacitance thereof, the effective surface area of an etching foil is extended so that the capacitance per unit area will be improved, whereby the effective surface area of the etching foil is extended. As part of such an etching technique, development of etchant composition and of current waveform to be applied at the time of etching is conducted. (Patent Documents 1 and 2).
In addition, an example of such a technique includes one by means of which capacitance is further improved by lowering an etching layer by applying pressure thereto. (Patent Document 3).
In recent years, digitalization of electronic information devices requires an electrolytic capacitor provided with this electrode foil to be smaller-sized and to have higher capacitance and lower impedance in a high frequency region. In particular, in the case of communication devices such as a personal computer or a cellular phone, a capacitor is strongly demanded having much higher capacitance in accordance with the higher operation speed of a CPU employed.
An example of a conventional and widely-used capacitor for a communication device includes a layered ceramic capacitor that meets the demand for miniaturization. However, this capacitor cannot meet the demand for higher capacitance. Hence, an electrolytic capacitor is in use as a capacitor having a low equivalent series resistance value (ESR value) and high capacitance, and allowing for miniaturization.
Besides, some attempts were made with respect to an electrode foil for electrolytic capacitor to achieve a further reduced ESR value by thickening the remaining core portion of an electrode foil, that is, an unetched portion thereof (Patent Documents 4 and 5).    Patent Document 1 Japanese Laid-open Patent Publication No. 2005-203529    Patent Document 2 Japanese Laid-open Patent Publication No. 2005-203530    Patent Document 3 Japanese Laid-open Patent Publication No. H10-189398    Patent Document 4 Japanese Laid-open Patent Publication No. 2003-59768    Patent Document 5 Japanese Laid-open Patent Publication No. 2003-59776
Meanwhile, electrolytic capacitor having such an electrode foil is for use in a vehicle. In vehicle use, the limited space for installation in a vehicle forms a restriction of the space for electronic parts to be employed therein. However, electronic control devices for in-vehicle use have increasing number of functions; an airbag, in particular, operates at an increasing number of places ranging from a cab seat, a passenger seat, a side and a curtain, whereby much higher capacitance is required for an electrolytic capacitor to be used as an energy source for operation of the air bag.
In spite of this, as stated above, the space for installing electrolytic capacitor is limited while the capacitor of the size similar to the conventional ones and having higher capacitance is required. Further, in order to supply energy for all those parts including a cab seat and a curtain, the required amount of capacitance is too high to be supported by an electrolytic foil produced by way of the conventional etching technology.

Electrode material for electrolytic capacitor


The present invention provides a process for the recombinant DNA production of a mature form of the PRRSV ORF 3 or ORF 4 protein. This is achieved by the co-expression of the PRRSV ORF 2, ORF 3 and ORF 4 proteins by the same cell.

The porcine reproductive respiratory syndrome virus (PRRSV) is the cause of a new porcine disease that has attacked over 5.000 North European pig farms since late 1990. This disease now called Porcine Reproductive Respiratory Syndrome (PRRS) is also known as Mystery Swine Disease. First, identified in Germany in December of 1990, the problem became increasingly critical in the beginning of 1991. In January and February of 1991 the disease spread to the Netherlands and Belgium. Outbreaks have also been reported from Spain. It is anticipated that the disease will become very costly from an economic standpoint, comparable to or even worse than Aujeszky's Disease.
The principal clinical signs in sows are anorexia and late abortion up to day 110 of pregnancy. With piglets a high incidence of stillborn and/or weak piglets in addition to respiratory problems are observed. In fatteners chronic pneumonia and increased mortality occur.
In order to develop a vaccine to protect pigs against PRRS or to develop a diagnostic method to determine infection in pigs, the causative agent of the disease has to be identified, isolated and made suitable as an immunogen in a vaccine or antigen in a diagnostic assay.
Conventional vaccines may comprise chemically inactivated virus vaccines or modified live-virus vaccines. However, inactivated vaccines require additional immunizations, disadvantageously contain adjuvants, are expensive to produce and are laborious to administer. Furthermore, some infectious virus particles may survive the inactivation process and cause disease after administration to the animal.
In general, attenuated live virus vaccines are preferred because they evoke an immune response often based on both humoral and cellular reactions. Up to now, such vaccines based on PRRSV strains can only be prepared by culturing and serial passaging of virulent strains in macrophage cell culture. However, because of this treatment uncontrolled mutations are introduced into the viral genome, resulting in a population of virus particles heterogeneous in their virulence and immunizing properties. In addition it is well known that such traditional attenuated live virus vaccines can revert to virulence resulting in disease of the inoculated animals and the possible spread of the pathogen to other animals. Furthermore, culturing of the PRRSV strain on a macrophage cell line is very laborious and results in a pour yield of the virus.
Improved vaccines, both live- and subunit vaccines, may be constructed based on recombinant DNA technology. These vaccines would only contain the necessary and relevant PRRSV immunogenic material capable of eliciting an immune response against the PRRSV pathogens, or the genetic information encoding said material, and not display above-mentioned disadvantages of the live or inactivated vaccines.
The causative agent of the disease is now known to be a small enveloped RNA virus, and the European type of this virus has been described by Wensvoort et al. (The Vet. Quarterly 13, 121-130, 1991). Its relatedness to Lactate Dehydrogenase-elevating virus (LDV) and Equine Arteritis virus has been described by Conzelmann et al. (Virology 193, 329-339, 1993), and by Meulenberg et al. (Virology 192, 62-72, 1993), thus placing the virus in the group of Arteriviridae.
A strain of this European type, called the "Lelystad virus" (LV) has been deposited with the Institut Pasteur, Paris, France under nr. I-1102, in connection with PCT WO 92/21375 by the Central Veterinary Institute, Lelystad, The Netherlands.
Another European strain has been described in EPA no. 91.202.646.5, and was deposited with the Collection Nationale de Cultures de Micro-organismes (CNCM) of the Institut Pasteur at Paris France under nr. I-1140.
This European strain has recently been described by Conzelmann et al. (Virology 193, 329-339, 1993).
The American type of the virus has been described by Benfield et al. (J. Vet. Diagn. Invest. 4, 127-133, 1992). A strain of the American type has been deposited with the ATCC under nr. VR-2332, and is mentioned in PCT WO 93/03760 and European Patent Application 0.529.584. An important observation was made by Wensvoort et al. (J. Vet. Diagn. Invest. 4, 134-138, 1992), early after the virus was found, when he compared American and European strains on the basis of their antigenic characteristics and demonstrated that the European and American strains display considerable antigenic differences.
The genomes of two European strains of PRRSV and parts of the genomes of US isolates have been molecularly cloned and sequenced (PCT WO 92/21375; Meulenberg et al., Virology 192, 62-72, 1993; Conzelmann et al., supra; Kwang et al., J. Vet. Diagn. Invest. 6, 293-296, 1994; Mardassi et al., J. Gen. Virol. 75, 681-685, 1994; Meng et al., Proc. 13th IPVS Congress, 61, 1994).
The RNA of the PRRSV genome comprises about 15 kb and 8 open reading frames (ORFs) can be identified therein, ORF 1A,B and ORFs 2 to 7. ORF 1A,B encodes a.o. the viral RNA polymerase, whereas the ORFs 2 to 6 encode the viral membrane (envelope) proteins. ORF 7 encodes the nucleocapsid protein. In infected cells a 3' coterminal nested set of six major subgenomic mRNAs can be demonstrated in both the European and US isolates (Meng et al., supra). Table 1 summarizes the characteristics of the ORFs encoding the structural proteins of PRRSV (Conzelmann et al., supra).
TABLE 1 ______________________________________ mRNA Calculated MW ORF (kb) Amino acids protein (kD) ______________________________________ 2 3.7 249 28.4 3 3.1 265 30.6 4 2.6 183 20.0 5 2.0 201 22.4 6 1.4 173 18.9 7 0.9 128 13.9 ______________________________________
The distribution of the ORFs on the PRRSV genome is shown in FIG. 1 and corresponds to that found by Meulenberg et al. (supra).
Little is known about the PRRSV proteins expressed by the ORFs mentioned before. 5 viral proteins of about 15-26 kD were identified in lysates of cells inoculated with an European or US PRRS isolate (Nelson et al., J. Clin. Microbiol. 31, 3184-3189, 1993 and Benfield et al, Proc. 13th IPVS Congress, 62, 1994). It was demonstrated that the ORF 7, ORF 6 and ORF 5 proteins are present in virions (Meulenberg et al., Virology 206, 155-163, 1995). It has been found now that two different forms, a small and a large form, of the ORF 3 and ORF 4 protein are present in cells infected with PRRSV, but only one form is present in purified virions isolated from the supernatant of infected cells. The two forms of each ORF protein are distinguished by the level of processing of their carbohydrate chains. The large forms, which are the forms present in the purified virions, are Endoglycosidase H (Endo-H) resistant, whereas the small forms are Endo-H sensitive. The substrate of the enzyme Endo-H is only the "high-mannosylated" form of the glycoproteins. This enzyme cleaves the oligosaccharide chain immediately after the carbohydrate group GlcNac which is coupled to the amino acid asparagin (Asn). More complex forms, i.e. forms in which the glycosylation process is complete, are resistant to Endo-H cleavage. The Endo-H resistance was used herein to determine the stage of the glycosylation process of the ORF 3 and 4 proteins and to distinguish the small ("high-mannose") forms of the ORF proteins from the large ("complex") form thereof. The enzyme Peptid-N-Glycohydrolase (PnGase-F) was used to obtain the completely deglycosalyted form (polypeptide backbone) of ORF 3 and 4. It was found that the ORF 3 and 4 glycoproteins incorporated in virons are the large ("complex") forms which resulted from their precursor small ("high mannose") forms by further processing, as a result of which said large forms became Endo-H resistant. The molecular weight (mw) as determined by SDS-PAGE of the ORF 3 and ORF 4 protein forms is shown in Table 2.
TABLE 2 ______________________________________ MW non-glycosylated MW small.sup.1 MW large.sup.2 ORF form (kD) form (kD) form (kD) ______________________________________ 3 26 41-44 55-60 4 15,5 32-35 40-47 ______________________________________ .sup.1 EndoH sensitive .sup.2 EndoH resistant
After expression of individual ORFs in eukaryotic cells transformed with the individual ORFs it was found that, in contrast to virus infected cells, exclusively the small forms of the ORF 3 and ORF 4 proteins were produced. Since the individual proteins are not completely processed in eukaryotic cells, most likely the transport of the proteins from the endoplasmic reticulum to the medial cisternae of the golgi apparatus is not possible. Surprisingly, it has been found now that in order to obtain the large forms of the PRRSV ORF 3 and ORF 4 proteins, co-expression of ORF 2, ORF 3 and ORF 4 in one cell is required and sufficient. During the infection process, animals are confronted with the mature (large) forms of the proteins. Therefore, the present invention provides a process for the recombinant DNA preparation of the mature large forms of PRRSV ORF 3 and ORF 4 proteins.

Expression of porcine reproductive respiratory syndrome virus polypeptides in the same cell


To provide a connector plug that makes it possible to facilitate a plurality of persons' confirmation of a connector plug before its removal or after its insertion and to prevent erroneous work. The connector plug according to the present invention has a discoloration member mounted on a gripping portion for pinching during work. The color of the discoloration member changes due to heat of a worker's fingertips when the worker pinches the connector plug or pressure when the worker pinches the connector plug. The discoloration member is discolored by one worker pinching the connector plug. Another worker looks at the discolored discoloration member, and then is able to confirm whether the connector plug is a work target.

At present, optical wiring is introduced at various locations, and optical connectors are essential in the wiring. In a location where optical wiring is intensively switched, as shown in FIG. 1, a patch panel or a communication rack 1 is installed, and optical connector adapters 2 are arranged in a high density. A worker needs to select an objective location from the optical connector adapters 2 arranged in a high density, and insert an optical connector plug 3 thereinto. In addition, in a case where the connected optical connector plug 3 is removed, it is necessary to pick out an optical connector plug which is a target to be removed from among optical connector plugs which are inserted, and to accurately remove the optical connector plug which is a target.
An SC connector plug 3A is shown in FIG. 2 as a typical optical connector plug 3. The SC connector plug 3A is constituted by a ferrule 4 for fixing an optical fiber, a housing 5 for providing a detachable function, and an optical fiber cord 6 for protecting the optical fiber. In a case where the SC connector plug 3A is inserted into and removed from a patch panel, a worker pinches a gripping portion 7, and performs the task.
In recent years, optical wiring in buildings has increased with an increase in the amount of information, and amid this, there are a large number of optical connector connecting portions in an optical fiber cable core management wiring board, a patch panel, or the like. In such a location, various measures have been taken in order to eliminate erroneous removal of optical connector plugs. For example, in Patent Literature 1, by providing the optical connector plug with a bar code, a device reads information of an optical connector plug which is a target and compares the information with management data to prevent erroneous removal. In addition, according to the invention of Patent Literature 2, in an optical patch panel, a plate-like jig is installed below an optical connector adapter, and the jig is provided with information of an optical connector plug, to thereby visualize the identification of the optical connector plug. In this manner, how to facilitate the identification of the connector plug is shown through a variety of techniques.

Connector plug, connector insertion method, and a connector removal method

NIPPON TELEGRAPH AND TELEPHONE CORPORATION


A compound resin wheel with two or more moldings integrated to form the resin wheel, wherein at least one of the two or more moldings made of a long fiber reinforced thermoplastic resin, the other molding or moldings made of metal and/or FRP.

1. Field of the Invention
The present invention relates to a compound resin wheel, and is particularly concerned with a lightweight and mass-producible compound resin wheel which is surpassing in mechanical characteristics such as impact resistance, bending strength, rigidity, heat resistance, fatigue resistance, creep resistance and the like.
2. Description of the Prior Art
Wheels, or automobile wheels, for example, have ever been made generally of steel or light alloys (such as aluminum alloy and magnesium alloy).
Steel wheels are fabricated by pressing or roll forming, however, a dimensional dispersion is quite unavoidable in most cases, and a deviation is easy to occur particularly on the roundness of a bead seat of the rim. Moreover, the steel wheels are heavy and hence are not preferable for lightweight construction of automobile parts so required.
In the meantime, wheels made of light alloys are stably formed in dimensions and, in addition, sharply reduced in weight to one third of the steel wheels, however, what is disadvantageous is that the material cost is three to five times higher than that of the steel wheels.
Now, the lightweight requirement for the automobile parts is very important from the viewpoint of energy saving on which an emphasis has been placed lately, and thus the wheels must be made lightweight in respect of the fuel cost and the maneuverability.
Under such circumstances, a resin wheel has been proposed for satisfying the lightweight construction and the dimensional stability and the low manufacturing cost. The resin wheel is formed mainly of FRP (fiber-reinforced plastic) obtained from mixing short or long reinforcing fibers in a resin, and hence is light in weight as compared with the metallic wheel, superior in dimensional stability, available for mass production and also for reduction of manufacturing cost, and is excellent, still further, in the aspect of design factors such as coloration and the like.
Meanwhile, almost all of the resin wheels under examination so far and all the resin wheels developed hitherto are those made by the general FRP manufacturing technique, and so formed by pressing a thermosetting resin such as unsaturated polyester, epoxy resin or the like and FRP consisting of glass fiber and others (Japanese Patent Unexamined Publication No. 61-135801). The resin wheels thus obtained are superior in rigidity, strength and so forth, since fibers are not so severely damaged at the time of forming. In addition, the thermosetting resin is used mainly therefor, and hence the resin wheels are also superior in heat resistance and creep resistance. However, such process is not suitable for forming those with a complicated shape (for example, such one as is considerably variable in wall thickness), and a forming cycle is so long, thus leading to an unsatisfactory productivity.
On the other hand, an injection molding may ensure a high productivity and is superior in the aspect of production cost, however, injection moldings are generally 1/3 to 1/5 low in strength as compared with compression moldings. Thus, the injection molding does not satisfy the requirements of strength and rigidity of the products, because the reinforcing, fibers are extremely short in length such as 1 mm or less as compared with materials (such as BMC, SMC and the like) used for compression molding so as to increase the fluidity of the materials.


A photocoupler includes a signal relay unit, a voltage regulation unit and a signal amplification unit. The signal relay unit transmits an optical signal from the primary side to the secondary side. The voltage regulation unit applies only a safe voltage to the signal relay unit. The voltage regulation unit has a greater withstand voltage than the signal relay unit has. The signal amplification unit amplifies signals sent from the signal relay unit. The withstand voltage of the signal amplification unit is also greater than that of the signal relay unit.

1. Field of the Invention:
The present invention generally relates to a high-voltage interface. In particular, it relates to a photocoupler that withstands a high voltage used for home electric appliances.
2. Description of the Related Art:
One of the most popular home electric appliances may be an air conditioner. Referring to FIG. 1, typically an air conditioning system includes an internal unit 1 and an external unit 2. Though not depicted, the external unit 2 may include a compressor, a fan, and other necessary components. The driving power for the external unit 2 is supplied from the internal unit 1 via a power cable 3. As illustrated, the power cable 3 includes a pair of conductive lines 3a and 3b which are insulated from each other. An alternating current of 100V may be carried by the power cable 3.
In addition to the power cable 3, a single conductive line 4 is used between the internal unit 1 and the external unit 2. The conductive line 4 transmits control signals to manage the operation of the external unit 2. For economy of the system, the power line 3b is also used for transmitting the control signals (thus, the power line 3b works as both power transmitter and control signal transmitter).
To properly operate the movable components in the external unit 2 (i.e. the compressor, the fan, etc.), the control signals supplied to the unit 2 should be free from electrical noise. To achieve this, use may be made of an interface (I/F) such as a photocoupler. The interface provided in the internal unit 1 is connected to the power line 3b and the control signal line 4.
FIG. 2 shows the principal components used in a conventional photocoupler PC1xe2x80x2. In the photocoupler PC1xe2x80x2, a photodiode PD1xe2x80x2 is provided on the primary side, while a phototransistor PT1xe2x80x2 and a transistor TR1xe2x80x2 are provided on the secondary side. The collectors of the respective transistors PT1xe2x80x2 and TR1xe2x80x2 are connected to a first output terminal, while the emitters of the respective transistors PT1xe2x80x2 and TR1xe2x80x2 are connected to a second output terminal. The first output terminal is connected to the power line 3b (FIG. 1), while the second output terminal to the control signal line 4.
In operation, an unduly high voltage may be applied to the two transistors PT1xe2x80x2 and TR1xe2x80x2 via the power line 3b. Thus, as aprecaution, the transistors PT1xe2x80x2 and TR1xe2x80x2 need to be designed as a high voltage device. In general, however, a high-voltage transistor tends to exhibit poor switching characteristics (i.e. slow response) due to the collector-base junction capacitance. This is disadvantageous because the interface using the high-voltage phototransistor PT1xe2x80x2 may fail to transmit the control signals properly.
The above problem may be overcome by providing an electrical connection between the base of the phototransistor PT1xe2x80x2 and the output terminal 2. With such a connection, the unfavorable charge appearing between the collector and the base of the phototransistor PT1xe2x80x2 will be eliminated.
The above scheme, however, will cause another problem. Specifically, for making a connection between the transistor PT1xe2x80x2 and the output terminal 2, an additional step is required. Due to this, the circuit layout of FIG. 3 will cost more than that of FIG. 2. Accordingly, the product photocoupler adopting the layout of FIG. 3 becomes expensive.
The present invention has been proposed under the circumstances described above. It is, therefore, an object of the present invention to provide an interface which has quick response and high withstand voltage, and which can be produced at a low cost.
According to the present invention, there is provided an interface which includes: a signal relay unit that transmits a signal from a primary side to a secondary side; and a voltage regulation unit that applies to the signal relay unit a voltage which is lower than a predetermined threshold, wherein the voltage regulation unit has a greater withstand voltage than the signal relay unit has.
Preferably, the signal relay unit includes a photodiode that emits light and a phototransistor that detects said light.
Preferably, the signal relay unit includes a protection package that encloses the photodiode and the phototransistor.
Preferably, the voltage regulation unit includes a first high-voltage transistor and a zener diode, wherein the first high-voltage transistor has a higher withstand voltage than the phototransistor has, and wherein the zener diode is connected in parallel to the phototransistor.
Preferably, the interface of the present invention further includes a signal amplification unit that amplifies a signal supplied from the signal relay unit.
Preferably, the signal amplification unit includes a second high-voltage transistor connected to the phototransistor of the signal relay unit, wherein the second high-voltage transistor has a greater withstand voltage than the phototransistor has.
Preferably, the phototransistor and the second high-voltage transistor provide, in combination, a Darlington transistor.
Preferably, the signal amplification unit includes a resistor which is disposed between the base and the emitter of the second high-voltage transistor.
Other features and advantages of the present invention will become apparent from the detailed description given below with reference to the accompanying drawings.

Optical interface with low-voltage relay unit and high-voltage regulation unit


A container for storing hazardous waste materials, particularly radioactive waste materials, includes a shell having a closed end and an open end, and a lid for closing the open end. A core assembly arranged in the shell divides the interior of the shell into a plurality of elongated compartments for receiving the waste materials. The shell may be formed from a plurality of identical segments welded to one another, each segment including plural compartments. Preferably, the shell, lid and core assembly are formed from a copper beryllium alloy. The containers may be positioned in a pair of parallel side-by-side rows to produce a self-shielding storage arrangement.

The management of hazardous waste materials, including radioactive, biological and chemical waste, is of critical concern to maintaining a safe environment. For chemical and biological wastes, the hazardous material initially may be contained in a vessel, and while in the vessel may be processed and rendered benign. Management of radioactive waste materials, however, raises special concerns since certain nuclear waste materials retain high levels of radioactivity for thousands of years. An initial concern in the management of these radioactive waste materials is the safe local containment of the materials as they are generated. Also of concern is the safe transport of the locally contained materials to specialized facilities for processing or for intermediate term or long-term storage. Thus, for example, high-level radioactive waste materials produced at nuclear utility sites are typically contained locally for a period of tens of years. Subsequently, plans call for these waste materials to be transported to a specialized facility for longer term storage and/or waste processing. In such intermediate term storage facilities, radioactive waste materials may be stored in containers for 40 to 100 years, with the containers being available for periodic integrity confirmation and the contents being accessible for retrieval and inspection. Subsequent to the intermediate storage period, the radioactive waste materials may be processed or transported to other specialized sites for long-term storage, for example, of from 300 to 1,000 years. One such long-term storage site is currently planned for the Tuff Repository in Nevada.
Presently, two arrangements for the short-term local storage of radioactive spent fuel rod assemblies predominate. Both arrangements have been designed to dissipate heat from the fuel rod assembles rapidly so as to prevent thermal breakdown of the assemblies as a result of overheating. In one arrangement, the spent nuclear fuel rod assemblies are stored exposed at the generation site in large pools of water. Elaborate systems are required not only to cool the water to a desired temperature, but also to chemically treat the water to provide radiation shielding between adjacent assemblies. In the other technique, the spent nuclear fuel rod assemblies are placed in racks surrounded by stainless steel containers which, in turn, are enclosed in concrete bunkers. Since stainless steel does not provide a sufficiently high thermal conductivity, a constant flow of air is forced through the containers to dissipate heat from the waste materials therein. This flow of air contacts the nuclear fuel rod assemblies directly and is then exhausted into the environment. Both of these arrangements require large storage areas, constant maintenance and rather elaborate systems to maintain the stability of the radioactive waste materials. Furthermore, where stainless steel containers are used, the containers are susceptible to swelling and corrosion, thereby jeopardizing the safety of the storage arrangement over long periods of time.
The growing inventories of spent nuclear fuels has resulted in an increasing urgency to develop containers and overall systems for the safe storage of these materials, both short term and long term. Despite the many efforts that have been made to address these concerns, there still exists a need for a simple, safe and economical system for containing and storing radioactive waste materials for prolonged periods of time. Preferably, such system will enable the waste materials to be accessed periodically for inspection and/or processing.

Dry storage arrangement for spent nuclear fuel containers


A mixed-gas beverage dispensing system for driving beverages from a container to a tap with a predetermined ratio of carbon dioxide (CO2) and nitrogen (N2) gas includes one or more monitors to detect excessive consumption of N2. The system may include a N2 generator, with a monitor monitoring the N2 generator to detect excessive operation thereof. The system may include a N2 reservoir, with a monitor monitoring the pressure in the N2 reservoir. The system may include a volumetric gas flow meter interposed in one or more mixed-gas distribution lines to monitor the flow of mixed gas. Upon detecting consumption of N2 gas in excess of a predetermined threshold, a monitor may trigger an audible, visual, or electronic alarm; may shut down operation of the system; and/or may switch to one or more backup gas tanks containing CO2, N2 or a predetermined blend thereof, for continued beverage dispensing operation.

The present invention relates generally to the field of beverage dispensing gas pressure systems and in particular to a system and method for detecting a gas leak, actuating an alarm, and activating a backup gas system to continue beverage dispensing operation.
Beverages, such as beer and increasingly, wine, are driven from kegs or other containers to be dispensed from a tap by pressurized gas. Most bars and restaurants maintain at least one large tank of carbon dioxide (CO2), which is necessary to provide carbonated water for a soda machine. Consequently, CO2 gas is often used to pressurize the beer kegs. Pressurizing beer kegs with CO2 injects excessive CO2 gas into the beer, causing excessive foaminess. This effect increases as the volume of CO2 relative to the volume of beer in the keg increases—that is, as the keg empties. In most cases, a bartender will swap out a keg when it is depleted to about 10% of its original volume, rather than waste time at the tap attempting to draw a beer without excessive foam.
Nitrogen gas (N2) is easily filtered from atmospheric air by a N2 generator, and may be stored in a pressurized tank for use in driving beverages to a tap, either alone or in combination with CO2 gas. N2 is an inert gas that contains no oxygen component. Pure N2 is preferred for driving wine, as it disallows oxidation of the wine and inhibits the growth of bacteria.
When beer is driven from kegs to a tap using pure N2, the beer retains only the CO2 resulting from its fermentation process, and is perceived as flat. The beer will contain bubbles, but may not generate a head when poured from the tap. Ideally, beer should be driven by a blend of CO2 and N2 gas to enhance its carbonation, but not pure CO2. Further, the ideal proportion of gases varies by beer.
A known beverage dispensing system includes a N2 generator that generates N2 from atmospheric air as a background activity, and stores the N2 gas in a pressurized container where it is available to drive beverages to taps. The system also connects to one or more conventional CO2 tanks. The system mixes N2 and CO2 gasses in optimal ratios for distribution to beer kegs. For example, most beer requires a 60/40 ratio of CO2 to N2; Guniess® beer requires a ratio of 25/75. The system may dispense pure N2 to drive wine.
Given the large margins in beer sales, eliminating a waste of approximately 10% per keg quickly pays for the lease or purchase of such a system, and thereafter delivers pure profit to the bar or restaurant. Bars and restaurants may purchase blended-gas beverage dispensing systems, or may lease them from a leasing company. In either case, if the system is installed and operated properly, the bar or restaurant, or the leasing company, will realize a normal operating life of the system. If there are fitting or hose leaks in the any portion of the beer dispensing operation, or if a bartender leaves the tap of an empty keg in the open position, the N2 generator may run for excessive hours. This increases the cost of operation through wasted energy costs, and shortens useful life of the system. This results in increased installed cost for the system, borne by the bar or restaurant, or the leasing company, which is responsible for maintaining the system.
Additionally, in the case of leased system, the monthly leasing fee is often determined by the hours of operation of the N2 generator. This practice correlates the lease fees to the actual amount of beer dispensed by the bar or restaurant. In this case, the detection of excess N2 consumption may directly lower the cost of leasing the system.

Beverage dispensing gas consumption detection with alarm and backup operation


A scanning confocal microscopes scans a sample with an incident beam of ultraviolet radiation, in a raster scan pattern, causing the sample to fluoresce and emit visible radiation, a portion of which retraces a 5 portion of the path optical of incident beam, to a dichroic mirror that separates it from the incident beam for detection by a photomultiplier tube. A clock signal for clocking the output of the photomultiplier tube is provided by a reference beam system that directs a reference beam onto the same scanning mirror as is the incident beam, at a coincident location on that mirror, and from there through a Ronchi grating having a uniform series of alternating transparent and opaque regions. The resulting pulsed reference beam is detected by a second photomultiplier tube, to produce a clock signal that is an accurate representation of the instantaneous scan rate of the reference beam and, thereby, the scanning incident beam.

1. Field of the Invention
The present invention relates generally to scanning confocal microscopes and, more particularly, to laser-scanning confocal microscopes that scans a sample with ultraviolet light and detect the resulting fluorescence.
2. Description of Related Art
In the scientific fields of physiology, cytobiology, etc., it is important to investigate the behavior of the intracellular ions of calcium, sodium, magnesium, etc. This is because these ions are thought to be closely linked with intracellular physioactivation. As part of a method of research on the behavior of the intracellular ions, fluorophores commonly are injected into cells. Such fluorophores combine uniquely with the certain species of ions within the cells, and fluoresce when irradiated with excitation light of specified wavelength.
By way of example, fluorescent probes indo-1, fura-2, fluo-3 and rhod-2 are known fluorophores useful in the detection of the calcium ions. Any of these fluorescent probes can be used to detect the presence of calcium ions within the cells. For example, the probe indo-1 fluoresces at wavelengths of either 405 nanometers (nm) or 485 nm in accordance with the concentration of the calcium ions, in response to excitation by ultraviolet radiation having a wavelength of about 350 nm. The probe fura-2, on the other hand, fluoresces at a wavelength of about 500 nm, in response to excitation by ultraviolet radiation having a wavelength of about 340 nm or 380 nm.
When the fluorescent probe has combined with the calcium ions and is excited by the ultraviolet light, it fluoresces in an amount that varies in accordance with the calcium ion concentration. Therefore, the concentration 5 of the calcium ions in each local area of a sample can be determined by measuring the intensity of the fluorescent light. The excitation and fluorescence detection can be carried out across sample surface, whereby a two-dimensional video image can be obtained. Further, a plurality of video images can be obtained in time series, whereby the time behavior of the ions can be investigated in detail.
Where the ratio between the intensities of the two peaks of the fluorescence spectra is detected under the ultraviolet excitation of the fluorescence probe indo-1, or where the ratio between the intensities of the respective peaks of the fluorescence spectra is detected under the alternate excitation operations of the fluorescent probe fura-2 with the two wavelengths of ultraviolet radiation, an accurate measurement of calcium ion concentration can be reliably obtained.
It is desirable to the scan the doped sample with an incident laser beam in a raster pattern and to produce from the resulting fluorescent radiation a standard video-format signal so that fluorescence of the sample can be viewed on a video display. For a true two-dimensional representation of the sample, the successive scans must be linear. It is known to linearize such scans by generating a reference beam that scans at the same rate as the incident laser beam and by directing that reference beam through a Ronchi grating to produce a pulsed beam from which a clock signal can be derived representative of the scanning speed. Although such a technique is effective in roughly linearizing non-linear scan data, the reference beam and incident laser beam do not always scan at rates that precisely track each other.
It should therefore be appreciated there is a need for a scanning confocal microscope that scans a sample in a raster scan pattern in which the scan data is a true representation of the sample's two-dimensional proportions. The present invention fulfills this need.

Scanning confocal microscope using fluorescence detection

The Regents of The University of California


Apparatus for restricting movement of a lawn implement shaft, for use in a lawn implement support system in cooperation with a vertically upstanding support member for horizontal support of shafted lawn implements during storage or transportation thereof including a support post for supporting a first end of a shafted lawn implement in conjunction with the vertically upstanding support member for supporting a second end of the shafted lawn implement. Further the apparatus includes a shaft support hook mounted to the support post, and projecting outwardly therefrom for a predetermined distance, the support hook being curved generally vertically and at a predetermined angle away from a first generally vertical plane defined by the support post, with a distal end of the shaft support hook being curved back toward a second vertical plane defined by the support post and perpendicular to the first vertical plane to define a shaft support region intermediate the hook and the support post. The present apparatus also includes a compression pin adjustably mounted to the support post adjacent the support hook for sliding movement therealong, the compression pin including a shaft abutment surface; and a device for fixing the compression pin at a predetermined position along the support post for restrictive contact with the lawn implement shaft.

The present invention relates broadly to racks and other skeletal support systems for tools and, more particularly, to an apparatus for restricting movement of a lawn implement for use with a lawn implement support system for storage or transportation thereof. The lawn implement is preferably a string trimmer having an elongate shaft.
Commercial lawn maintenance providers typically carry a number of lawn implements from job to job including string trimmers. As is generally known, string trimmers are lawn implements having an elongate shaft with a motor on one end of the shaft and a string head on the other end of the shaft. Such implements are considered a requirement in providing proper lawn care.
Trailers towed by pickups are typically used in transporting lawn implements from job to job. It is known to provide racks for string trimmers which are fitted to the sides of the trailers, projecting upwardly therefrom. These racks include vertical posts which are spaced a predetermined distance apart and support a plurality of string trimmers. Typically, some form of hook or tie is used to attached the string trimmer to the rack. Often, the string trimmers are loosely supported on the racks and the trimmers are bounced and jostled about as the suspensionless or barely-sprung trailer is towed behind a pickup truck. Further, the loosely held string trimmers may be susceptible to theft.
It would therefore increase the life of the string trimmers if they could be held more tightly against the rack.

Apparatus for restricting movement of a lawn implement shaft during storage or transportation thereof


In an electronic device having a processor, a visual display, apparatus for entering data into said device, and an electronic memory, a method for reliably determining whether confidential handwritten or voice data entered into the electronic device for processing has been recognized by the device as representing a character the user intended to enter, comprising the steps of receiving a data entry, translating the entry into digital signals and combining the digital signals to create a character, saving the character in electronic memory, commencing a timing sequence, displaying the character on the visual display, awaiting the expiration of the timing sequence, and replacing the character with a mask character on the visual display and, if the character was incorrect, allowing the user to re-enter the character and, if the character was correct, accepting another character, and, when all characters have been entered, sending the saved characters to the processor for processing.

As used herein, the term "character" refers to a sequence of binary digits representing information that can be recognized by a processing system. As such, a "character" may represent a visual symbol capable of being displayed; a system command to be executed by the system; a digital signal that is generated through the pressing of a button, switch, knob, touchpad, or other user initiated signaling device; a digital signal generated by the system; or any other digital sequence carrying information into, out of, or within the system. "Data" shall refer to the confidential input entered by the user, and may constitute, for example, conventional input from a keyboard or keypad, handwriting applied to a digitizer pad, vocal entries received by a microphone, whistling or other mouth-and-breath combinations, touchpads, touch screens, and other means for entering data into processing systems. The term "word" refers to the confidential information saved in a memory buffer for processing after data entry has been completed.
Methods of entering data into processing systems through a user interface include both precise and imprecise entry methods. Data entered is converted from its raw form into a character that may then be processed in accordance with standard processing methods. Because the data may be seen by the conversion means as constituting something other than what the user intended, there is a possibility that the wrong character will be interpreted by the system.
When confidential data is to be entered into a processing system, the information being entered should not be retained on a display where it can be viewed by persons unauthorized to receive the data. Conventional means for entering confidential data do not echo the data to the display. However, where confidential information is to be entered, but not viewed, there is a possibility that incorrect data will be received.
It is an object of the present invention to provide a data-entry system that will accept a confidential data entry, convert the data to a character, save and temporarily display the character to a user so that the accuracy of the entered confidential data may be verified, and then replace the displayed character with a mask character. This and other objects of the invention will be described in the following descriptions.

Verification system for confidential data input


A purple LED is fixed onto lead frames in the cup of a frame using a mount, and the purple LED is sealed by filling a sealant of transparent resin into the cup. Red/green/blue phosphors that absorb a light emitted by the purple LED and emit lights having red, green, blue wavelengths different from the wavelength of this absorbed light are mixed into the sealant. A yellow phosphor that absorbs a light emitted by the purple LED and emits a light having a yellow wavelength different from the wavelength of this absorbed light is additionally mixed into the sealant in such a white light emitting device.

In general, a light emitting element used for a light emitting device includes an inorganic LED (Light Emitting Diode), an organic LED, a laser diode, an inorganic thick film electroluminescence sheet or an inorganic thin film electroluminescence parts and the like. Among others, LED stands out in characteristics such as long life, space-saving, good resistance to impact shock, and further, capable of emitting a light in a narrow spectral band.
A number of luminous colors, i.e. a number of luminous colors in a particularly wide spectral band cannot be realized or can be realized only in an inefficient manner by light emission inherent to an active semiconductor material in LED. Especially, such tendency is remarkable in case of white light emission.
According to the well-known technical level, a luminous color which cannot be essentially realized is attained by a wavelength conversion technique. The wavelength conversion technique is essentially based on the following principle. Namely, at least one phosphor is placed on an LED, and the light emitted from the LED is absorbed by the phosphor to emit a light having a wavelength different from that of the light absorbed. In other words, a light emitted is absorbed by an LED, and then, a photoluminescence light is radiated with another luminous color.
As a light emitting device emitting a light of white color based on the principle as described above, a white LED lamp wherein a light emitted from a purple LED is wavelength-converted by phosphors of respective colors of red/green/blue (hereinafter referred to as "red/green/blue phosphors in case of expressing collectively) which are in practical use at present, to emit a light is well known. Respective components of the red/green/blue phosphors are as follows.
Red phosphor: La2O2S:Eu, Sm (YOS:Eu)
Green phosphor: 3 (Ba, Mg, Eu, Mu) O.8Al2O3(BAM:Eu, Mn)
Blue phosphor: (Sr, Ca, Ba, Eu)10 (PO4)6.Cl2
However, there is such a problem that color rendering properties are low in a conventional white light emitting device (white LED lamp).
FIG. 1 is a spectral diagram indicating emission intensity of a conventional white LED lamp. As shown in the figure, since there is scarcely a yellow component having a wavelength of 560 to 590 nm, an average color rendering evaluation number Ra of the white LED lamp is as low as about 50 to 60. In a usual fluorescent lamp, an average color rendering evaluation number Ra is about 80 to 90, and ideal is 100.
On the other hand, in a white light emitting device wherein white color is realized by a combination of a blue LED and a phosphor, an emission wavelength of the blue LED shifts to a long wavelength side with increase of temperature rise, so that there is a case where color deviation appears in the white, light emitting device.
An object of the present invention is to provide a white light emitting device having improved color rendering properties.
Furthermore, another object of the present invention is to provide a white light emitting device in which color deviation is hard to appear.


A system and method may include: providing to a device user in response to one of a user request for troubleshooting assistance and a mobile telecommunications user device monitoring software conclusion that a problem exists, a diagnostic application specific to the mobile telecommunication user device of the device user; receiving from the device user an indication of a problem with the mobile telecommunication user device experienced by the device user; selecting an application update; providing to the device user the application update updating an application running on the mobile telecommunication user device; and determining whether the problem has been solved. If determining indicates that the problem has not been solved the method may further include deleting the application and further determining whether the problem has been solved, and if so forwarding problem solution data to a knowledge database.

A large cost is inflicted on cellular network operators by the user practice of returning devices for repair that are not actually defective. There are several reasons for this problem: some operating intermittencies may not be caught during in store testing of a defective device, or the problem may be caused by peripheral devices that are not returned with the supposedly faulty phone. A large portion of the problem may be attributed to user configuration errors, network configuration errors, or user software add-ons that are installable in the phone but may not be completely compatible with the particular phone set up and its particular network. Only a small fraction of returns are due to actual failure of the hardware.
In some cases more thorough diagnostics of devices with problems are needed than the diagnostics that are available currently. These diagnostics should not merely rely on internal functional diagnostics, but they should also include hardware configuration diagnostics, program configuration diagnostics, and network configuration diagnostics; and they should also look for other factors, including but not limited to program compatibility issues.
Often the exchange of data objects between different phones is desired or required. Some phones do not support such a feature; other phones have very limited ability. For example, such phones may allow exchange of an object such as a business card, but do not support exchange of pictures or other larger graphic images.
What is needed is a system and method for tracking and detecting device failures, and by doing so analyzing the problems and detecting the incorrect return of hardware, thus reducing dramatically the overall cost of network operations. What is also needed is a system and method that allows the exchange of any kind of object between two phones, whether exchange is originally supported by these phones or not, in a secure and safe manner.

This patent is subject to a terminal disclaimer.

System and method for enhanced diagnostics on mobile communication devices


A wiring structure can include a wire harness and a conductive shielding cover. The wiring structure can be subjected to swing, heat, and the countermeasure against electromagnetic shield. In the wiring structure, a conducting path of a harness body of the wire harness and a conductive shielding cover that covers the wire harness are partly put into at least one of a contact state and a holding state directly or indirectly.

In an electric vehicle and a hybrid vehicle, for example, a motor unit and an inverter unit mounted in these vehicles are connected via a wire harness for large current and high voltage (see Patent Literature 1). The wire harness for large current and high voltage is subjected to countermeasure against electromagnetic shield.

Wiring structure of wire harness and shielding cover


A display panel and a method for manufacturing the same and a display device are disclosed. The display substrate includes: a base substrate having a plurality of pixel areas, at least one of the plurality of pixel areas including a first electrode layer, an organic functional layer and a second electrode layer stacked in sequence on the base substrate; and a third electrode layer on a side of the second electrode layer facing away from the base substrate; wherein the third electrode layer is electrically connected to the second electrode layer.

A display substrate in an organic light emitting diode (OLED) display panel includes an array of thin film transistors and an array of light emitting elements. The array of thin film transistors includes a plurality of thin film transistors. The array of light emitting elements includes an anode layer, a cathode layer and an organic functional layer between the anode layer and the cathode layer. The anode layer includes a plurality of anodes that are connected in one-to-one correspondence with drain electrodes of the thin film transistors.
The cathode layer is formed typically by sputtering transparent metal oxide such as indium tin oxide (ITO) or evaporating a partially transparent metal material over the organic functional layer.

Display substrate and method for manufacturing the same and display device


A system and method of controlling a scissors lift vehicle are provided. The scissors lift vehicle system includes a carriage including a plurality of independently steerable wheel assemblies configured to engage a travel surface. The plurality of independently steerable wheel assemblies, each steerable about a steer axis of rotation include one of the plurality of wheel assemblies being designated a master wheel and the remaining wheel assemblies being designated slave wheels. The wheel assemblies each include a variable-speed steer actuator configured to rotate a respective wheel assembly about the steer axis of rotation of that wheel assembly at a selectable rate. The wheel assemblies each also include a wheel including a respective drive axis of rotation and a variable-speed drive actuator configured to rotate that wheel about a respective steer axis of rotation at a selectable rate.

This description relates to lift devices, and, more particularly, to mobile elevating work platform systems and methods of controlling the operation of mobile elevating work platforms.
Various types of mobile elevating work platforms have a lift mechanism that can be moved in a vertical direction to bring a worker close to otherwise inaccessible locations. The lift mechanism is often mounted to a self-propelled carriage or chassis having wheels for moving the platform between work areas. In one type of mobile elevating work platforms, the lift mechanism to achieve the vertical lift is often referred to as a "scissor lift," in which a plurality of linked, folding supports oriented in a crisscross or "X" pattern in a "scissors stack." The upward motion is achieved by the application of a force to a set of parallel linkages, elongating the crossing pattern, and propelling the work platform vertically. With the scissors stack mounted on the carriage above the wheels, the wheels, steering configuration, and propulsion configuration are typically a standard arrangement of axles, wheels, linkage arms, and motors or drives. Such convention steering limits the motion of the mobile work platform. For example, a turn radius is limited and the ability to crab the platform in a direction without turning it is virtually non-existent.
Scissors lift devices are most useful if they are self-propelled. Current scissor lift designs have many of the propelling features mounted under the scissors lift assembly. A hydraulic system, electrical system including batteries, and a control system are also typically mounted on the carriage below the scissors lift assembly. Additionally, axles, steering and transmission components are also mounted on the carriage under the scissors lift assembly. Accordingly, because of the equipment located under the scissors lift assembly on the carriage, the height of the work platform that carries a user to the work area is greatly elevated above the floor surface. To gain access to the work platform of known scissors lift assemblies, the user must climb onto the platform, usually using several ladder steps attached to the carriage and/or platform, and usually carrying tools, equipment, and/or repair parts. Such access is dangerous and laborious for the user. Moreover, mounting the scissors lift assembly on top of the carriage increases the height of the scissors lift vehicle when the scissors lift assembly is fully retracted. The increased height limits areas that the scissors lift vehicle can access.

Method and system for a lift device having independently steerable wheels


A data processing system program to develop, train, and implement a neural network for identifying customers who represent a bad debt risk is disclosed. A feature vector is applied to a neural network to generate outputs that approximate the relative likelihood that customers who are the subjects of the records used to generate the feature vector will be a bad debt risk. Statistical values relating categorical attributes of the customers to the likelihood of their becoming a bad debt risk are substituted for the categorical attributes, and the attributes are normalized before the feature vector is applied to the network. In one embodiment the customers are customers of a long distance service provider.

With modem technology it has been possible to collect extensive records, which describe attributes of subjects of the records. In particular, companies can develop records that describe many attributes of their customers. It would be desirable if these records could be used to predict which customers, i.e., subjects of the records, are relatively more likely to have a particular characteristic which is not explicitly described by the attributes in the records. That is, it would be desirable if the records could be rank ordered in a manner that correlates with the relative likelihood that the corresponding customers would, for example, buy a particular product. It would be particularly desirable if the records could be rank ordered in a manner correlating with the relative likelihood that customers would become bad debt risks. By "bad debt risk", or sometimes "toll risk" in the context of long distance services, herein is meant a customer who is sufficiently delinquent in payment to create a substantial risk of non-payment.
This need is particularly acute for long distance telephone carriers where at any time totals of hundreds of millions of dollars are owed by millions of customers for long distance telephone service. The need for an early identification of toll risks is even greater for carriers, such as the assignee of the present invention, who have a "no-denial" policy; that is carriers who do not use any criteria to deny service to customers. Previously the above mentioned assignee has used two "toll risk" strategies to deal with this bad debt problem: a High Toll System (HTS), and a Collection Strategy System (CSS). The High Toll System generates alarms based on dollar amounts and call detail thresholds. The dollar amount and call detail from the High Toll alarm are then compared to the customer's normal billing history. Computer algorithms and/or human analysis are then used to determine if the customer's service should be deactivated, sometimes hereinafter referred to "blocking the account". The other system, the Collection Strategy System, is a time based collection management system triggered from the last paid invoice. CSS used a commercial credit score to predict the likelihood of an applicant or established customer becoming a serious credit risk to determine which collection strategy to use for each of the applicants or customers. Currently CSS uses various collection strategies and timelines based on the calculated risk of bad debt before a warning is sent or other action is taken.
While the above described systems have proven to be somewhat effective it would clearly be desirable to reduce the losses attributed to bad debt. Further, it has been found that as much as two thirds of all write-offs come from one third of new customers. Consequently there is a need for a system that would allow prompt analysis of the behavior of new customers and allow early intervention to minimize delinquencies.


Micromechanically producible capacitively operating pressure sensor, in which there is a diaphragm, formed by a diaphragm layer (5), on a silicon substrate (1) over a hollow (4) in an auxiliary layer (3), and in which there is, on the side of the diaphragm averted from the hollow (4) and at a distance therefrom, an electrode formed by an electrode layer (8) with recesses (9) therein as a counter-electrode to the electrically conductive diaphragm layer (5). Given a rise in the external pressure, it is possible by applying a voltage between the diaphragm layer (5) and the electrode layer (8) to prevent the diaphragm from deflecting in the direction of the substrate, and to determine the magnitude of the pressure from the voltage required therefor.

The present invention relates to a micromechanically producible capacitive pressure sensor.
A closed chamber at a reference pressure is sealed by an elastic diaphragm which is exposed to an external pressure. The electrically conductive diaphragm forms a plate capacitor with the opposite side of this chamber. The diaphragm is deformed because of the pressure difference between the external pressure and the internal reference pressure. The capacitance of this capacitor changes owing to the change in the distance between the diaphragm and the rear side of the chamber, which acts as a counter-electrode. The external pressure can be determined from this change in capacitance.
U.S. Pat. No. 5,095,401 by Paul M. Zavracky et al., describes pressure sensors on an SOI substrate, in which a hollow is produced by removing a region, made from silicon oxide and produced by means of LOCOS, through small openings in a layer applied thereupon. These openings are subsequently sealed by oxidizing the adjoining silicon or by applying a further layer made from silicon nitride, polysilicon or the like. This patent specification also describes the use of the method of production specified there for producing pressure sensors which measure in a capacitive fashion. A constituent of the diaphragm of this pressure sensor is a crystallized silicon layer which is used outside the pressure sensor to integrate electronic components, and is used in the region of the diaphragm to form piezoelectric resistors.