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For the design of digital circuits (e.g., on the scale of Very Large Scale Integration (VLSI) technology), designers often employ computer-aided techniques. Standard languages such as Hardware Description Languages (HDLs) have been developed to describe digital circuits to aid in the design and simulation of complex digital circuits. Several hardware description languages, such as VHDL and Verilog, have evolved as industry standards. VHDL and Verilog are general-purpose hardware description languages that allow definition of a hardware model at the gate level, the register transfer level (RTL) or the behavioral level using abstract data types. As device technology continues to advance, various product design tools have been developed to adapt HDLs for use with newer devices and design styles.
In designing an integrated circuit with an HDL code, the code is first written and then compiled by an HDL compiler. The HDL source code describes at some level the circuit elements, and the compiler produces an RTL netlist from this compilation. The RTL netlist is typically a technology independent netlist in that it is independent of the technology/architecture of a specific vendor's integrated circuit, such as field programmable gate arrays (FPGA) or an application-specific integrated circuit (ASIC). The RTL netlist corresponds to a schematic representation of circuit elements (as opposed to a behavioral representation). A mapping operation is then performed to convert from the technology independent RTL netlist to a technology specific netlist, which can be used to create circuits in the vendor's technology/architecture. It is well known that FPGA vendors utilize different technology/architecture to implement logic circuits within their integrated circuits. Thus, the technology independent RTL netlist is mapped to create a netlist, which is specific to a particular vendor's technology/architecture.
One operation, which is often desirable in this process, is to plan the layout of a particular integrated circuit and to control timing problems and to manage interconnections between regions of an integrated circuit. This is sometimes referred to as “floor planning.” A typical floor planning operation divides the circuit area of an integrated circuit into regions, sometimes called “blocks,” and then assigns logic to reside in a block. These regions may be rectangular or non-rectangular. This operation has two effects: the estimation error for the location of the logic is reduced from the size of the integrated circuit to the size of the block (which tends to reduce errors in timing estimates), and the placement and routing typically runs faster because as it has been reduced from one very large problem into a series of simpler problems.
After placement of components on the chip and routing of wires between components, timing analysis (e.g., transient timing simulation, or static timing analysis) can be performed to accurately determine the signal delays between logic elements. Back annotation can be performed to update a more-abstract design with information from later design stages. For example, back annotation reads wire delay information and placement information from the placement and route database to annotate the logic synthesis design. Back annotated delay information can be used to identify critical paths where the timing requirements are not satisfied; and logic synthesis may be improved to meet the timing requirements.
After the design layout (e.g., the placement and routing), only limited optimizations like resizing or buffering (known as in place optimizations) are typically performed. However, in place optimizations can provide only limited improvements. When the in place optimization cannot adjust the solution to meet the timing constraint, adjustment to the logic synthesis may be performed, leading to the expensive iteration between logic synthesis and placement and routing.
Timing analysis results can be expressed in terms of slack, which is the difference between the desired delay and the actual (estimated or computed) delay. When the desired delay is larger than the actual delay, the slack is positive; otherwise, the slack is negative. Typically, it is necessary to make the slack positive (or close to zero) to meet the timing requirement (e.g., through reducing the wire delay to increase the slack). For example, during synthesis, a total negative slack algorithm (e.g., used in a circuit design compiler, Synplify, available from Synplicity, Inc., California) considers all instances whose slack is negative as candidates for improvement, since any one of the candidates with negative slack could become critical after physical design. It is typical to make the slack positive to ensure that the timing requirements are met.
After the synthesis transformation, the placement and routing is performed to generate a technology/architecture dependent design layout, which can be implemented on a vendor's technology/architecture dependent integrated circuit, such as field programmable gate arrays (FPGA) or an application-specific integrated circuit (ASIC). | {
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Conventional display panels generally comprise a color film substrate and an array substrate which are arranged oppositely, and a liquid crystal layer between the color film substrate and the array substrate. The color film substrate comprises a black matrix layer and a second alignment layer over the black matrix layer which covers the color film substrate. The array substrate comprises a plurality of pixel units which are arranged in a matrix, thin film transistors which correspond to each pixel unit, and a first alignment layer which covers the array substrate.
As shown in FIG. 1, it has been found that when a display panel is subject to a pressure, a relative displacement d develops between a color film substrate 10′ and an array substrate 20′ in a direction parallel with the display panel. At the same time, at the position of the display panel where it is subject to the pressure, the distance between the array substrate and the color film substrate also changes. The relative displacement between the color film substrate and the array substrate will cause the liquid crystal to flow locally, thus leading to ripples. In addition, the relative displacement d between the color film substrate 10′ and the array substrate 20′ in the direction parallel with the display panel tends to cause a black matrix layer 101′ to offset in position, thus leading to light leakage around the pixel unit. When the display panel is a twisted nematic (TN) model display panel, the rubbing trace is relatively shallow. As a result, in regions of the alignment layer in the color film substrate 10′ near metal lines (i.e., around the pixel unit), the effect on the direction of the liquid crystal molecules 30′ is relatively small. | {
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Refrigerators that include both cooler and freezer compartments frequently include two access doors mounted on their front. Models carrying two doors on their front have those doors arranged in various configurations. Some include upper and lower doors where one opens into the freezer compartment while the other opens into the cooler compartment. Other models have side-by-side doors for freezer and refrigerator compartments.
In all of these configurations the depth of all of the various compartments is very nearly equal to the overall depth of the refrigerator from front to rear. And, when the refrigerator is crowded with items to be kept cool, or frozen, items stored away from the door at the rear of the compartment frequently become forgotten and may spoil. This is particularly true for refrigerators with multiple doors in the front because each door must then be smaller, and one's vantage into the compartment is thus reduced. Furthermore, to remove an item from the rear of a conventional refrigerator, it may be necessary to remove many of the items in front of it first and later replace them after the desired item has been removed. | {
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This invention relates to an image processing apparatus, such as an image processing apparatus having an internal function for communicating with external equipment.
Control of a device-such as a copier can be managed in a number of ways. For example, (1) the user of the device is specified using a card such as a control card or IC card mainly for the purpose of calculating a user fee for a copier; (2) a control key is provided for limiting use solely to specific individuals, as in the case of a color copier; and (3) a system is established in which the device is connected to a service location via a communication line so that information may be concentrated and managed at the service location mainly for the purpose of improving the servicing of the device and collecting billing data.
With regard to devices such as color copiers for which there is the danger of improper use, management stricter than that for ordinary copiers currently is being carried out through an operation such as customer control performed at the shop level.
In recent years, the widespread use of high-resolution color copiers has been accompanied by conspicuous examples of improper use in which management of the aforementioned kind is evaded. A more effective method of managing devices of the aforementioned type is desired. | {
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This invention relates to methods of manufacture of semiconductor devices, and more particularly to methods of manufacture of features of semiconductor devices by a sequence of steps including hard mask forming techniques.
Contemporary integrated circuit products require a large number of on-chip memory devices. On a typical microprocessor chip, more than two-thirds (⅔) of the surface area of the chip is occupied by Static Random Access Memory (SRAM) devices.
As integrated circuit dimensions inexorably become smaller and smaller thereby reducing the size of FET devices, we have found that it becomes more and more difficult to continue the trend of scaling SRAM devices to smaller sizes, mainly due to limitations of photolithographic resolution.
Using spacers to pattern sublithographic single features having constant widths has been proposed for FinFET patterning. A prior art approach to forming RSD regions in FinFET devices which illustrates the problems described above is shown in a paper by Yang-Kyu Choi, Tsu-Jae King, and Chenming Hu entitled “A Spacer Patterning Technology for Nanoscale CMOS” IEEE Transactions on Electron Devices, Vol. 49, No. 3, March 2002, PP. 436-441 describes a spacer patterning technology using a sacrificial layer and CVD spacer layer wherein the minimum sized features are finished not by photolithography but the CVD film thickness A set of FinFET devices is formed a Silicon-On-Insulator (SOI) substrate formed of a Buried Oxide (BOX) substrate covered with a thin insulator layer covered in turn by a polysilicon layer covered in turn by a silicon oxide hard mask layer. Two parallel, rectangular sacrificial SiGe features with vertical sidewalls are formed on the surface of the hard mask layer. Next, the sidewalls of the SiGe features are lined with Phospho-Silicate Glass (PSG) sidewall spacers, which also have vertical sidewalls. Then the sacrificial SiGe features are removed by selective dry etching leaving PSG spacer structures. Residues of SiGe were then removed by a selective wet etch. Then two source drains masks were then formed across the distal ends of the PSG spacer structures. Next, source/drain regions and fins of a FinFET device are formed by dry etching away the hard mask in a CF4 atmosphere and the polysilicon unprotected by the masks and the PSG features by etching in Cl2 and HBr gas atmosphere. However, the FinFET application described by Choi et al. is very limited because the width of the patterned feature can not be adjusted.
In an SRAM device, it is required that the pull down NFET must be stronger than the pass-gate NFET in order for SRAM to be stable, i.e., not to be disturbed during the read process. This requires width of the pull down NFET must be greater than the width of the pass gate.
U.S. Pat. No. 6,709,982 of Buynoski et al. entitled “Double spacer FinFET Formation” describes a method for forming a group of structures in a semiconductor device. Start by forming a conductive layer on a substrate, where the conductive layer includes a conductive material. Then form an oxide layer over the conductive layer. Then etch at least one opening in the oxide layer, fill at least one opening with the conductive material, etch the conductive material to form spacers along sidewalls of that one opening, and remove the oxide layer and a portion of the conductive layer to form the group of structures.
U.S. Pat. No. 5,023,203 of Choi entitled “Method of Patterning Fine Line Width Semiconductor Topology Using a Spacer” describes a method for reducing the line widths produced by patterning a semiconductor substrate with a multilayer resist mask employing a spacer-forming oxide layer over the mask after an aperture for exposing a lower resist layer has been formed in an upper portion of the multilayer mask, but prior to etching a lower resist layer. The oxide layer is subjected to a dry systemic etch to vertically remove material of the oxide layer down to the surface of the lower resist layer. Because of the substantial step coverage of the oxide layer, a spacer or stringer portion remains along the sidewalls of the original aperture in the upper portion of the mask, whereby the dimensions of the exposure window are reduced. Retaining this sidewall spacer as an integral part of mask structure permits narrower line widths to be replicated in the underlying substrate. | {
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The present invention relates to software documentation, and more specifically, to automated translation of screen images for software documentation.
In order to assist a user in learning how to use a software product, software documentation is often provided to step the user through a series of tasks. The documentation typically includes text describing the actions to be taken, as well as images of screens displayed by the application so that the user can visually see the expected screens together with the fields where data needs to be entered, the buttons to be pressed, and/or the menu selections to be taken. Generating and embedding images of screens, or screen shots, for software documentation is labor intensive when the documentation has to be made available in more than one language.
Typically, software is written, tested, and documented in a primary language, usually the native language of the software developers. The text that is included in the software application, both the labels and messages of the application itself, and the text in the documentation, is sent to translation experts who translate the text from the primary language into the desired other languages.
If the documentation includes screen shots from the application stored in image formats, such as .jpg or .png, translating the text in the screen shot is a complex task. Even if the literals can be located within the image and removed, and translated text inserted, the translated text is typically a different length than the original text. The translated text can end up clipped and/or overflowing into other areas of the screen, and the resulting screen is not the screen that the user will actually see when running the software application.
One approach is not to include screen shots in the documentation to avoid the complexity of translating literals within a captured image file. Another approach is to prepare the software documentation in the original language with original screen shots and then recreate the screen shots in the secondary language by executing the software application being documented. The application is re-run in the secondary language until the same point is reached that the original screen shot was taken and a screen capture is re-taken of the application in the secondary language. In this approach, the translation step is no longer just text but involves re-executing the application in the secondary language which includes setting up the correct environment for the software to run, ideally with the same data as the original so that the application functions and behaves in the same way as the original. This requires that the team who performs the translation of the GUI strings to have technical skills in order to launch and drive the software product being translated. | {
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1. Field of the Invention
The present invention relates to portable communication equipment and, more particularly to a hinge mechanism for use in a portable communication apparatus such as a portable telephone.
2. Description of the Related Art
In general, a foldable portable telephone is composed of a main body and a foldable portion which is rotatably supported on a single shaft by a hinge mechanism to rotate it between open and closed positions. A rotation of the foldable portion is preferably restricted and held at a desired angle with respect to the main body to allow stable and easy operation. There have been known a large number of single mechanisms that restrict and maintain a rotation of the foldable portion. Further preferably, a force required rotating the foldable portion between opened and closed positions is kept constant.
Such a hinge mechanism can be achieved by combining an elastic part such as a leaf spring or a coil spring and a well-known positioning and holding means using the fit between a ball and a recess. For example, Japanese Utility Model Registration No. 2525942 discloses a hinge mechanism in which a protrusion biased by a coil spring is engaged in a recess to hold the foldable part in position. Japanese Patent Unexamined Publication No. 8-218721 discloses a hinge mechanism with a fixing function in which a protrusion of a slidable cam biased by a coil spring is engaged in a recess of a fixed cam to hold the foldable part in position.
Needless to say, in the field of portable telephones, a drastic reduction in size and weight is demanded more and more. Although miniaturization of a leaf spring or a coil spring is also needed, the miniaturization makes it more difficult to provide the leaf spring or coil spring with a spring constant as large as necessary. A spring made of metal blocks weight reduction. A complicated mechanism composed of a lot of parts blocks cost reduction. | {
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(1) FIeld of the Invention:
The present relates generally to lift systems for agricultural implements, and more specifically, to a hydraulic lift system raising and lowering multi-section implements between raised transport and lowered depthcontrolled working positions.
(2) Related Art:
Large tillage implements often have a lift and depth control circuit such as depicted in FIG. 1 of in U.S. Pat. No. 3,663,032, of common ownership with the present application. Two lift cylinders connected to the lift wheel assemblies on the main frame of the implement are plumbed in parallel with each other and are connected through a mechanical member such as a rockshaft. The rockshaft keeps the opposite sides of the implement raising and lowering in unison and keeps a substantially uniform depth across the implement. Outrigger or wing frames pivotally connected to the opposite ends of the main frames each include a lift assembly with a cylinder connected in series with the nearest rockshaft cylinder to maintain a fairly uniform height across the width of the implement. However, uneven vertical forces across the width of the implement often cause rockshaft torsional wind-up which results in uneven depth, damage to the rockshaft, and side forces making steering of the towing vehicle more difficult. The problem of uneven forces is compounded since the wind-up of the rockshaft and the resulting change in displacement of the rockshaft cylinders causes the corresponding wing cylinders to move in the same direction. If the wing on one side starts digging in too deeply, the rockshaft cylinder which is connected in series with the wing cylinder will cause the corresponding side of the main frame to dig in more deeply also while the opposite side of the main frame will actually decrease in depth. Therefore the system is unstable in that initial reaction of uneven load tends to cause the loading to become more uneven. Although circuits have been proposed which hydraulically isolate the left-hand and the right-hand circuits when operating in the field, these circuits have added cost and complexity to the hydraulic system. | {
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A conventional hydraulic system includes a pump that draws low-pressure fluid from a tank, pressurizes the fluid, and makes the pressurized fluid available to multiple different actuators for use in moving the actuators. In this arrangement, a speed of each actuator can be independently controlled by selectively throttling (i.e., restricting) a flow of the pressurized fluid from the pump into each actuator. For example, to move a particular actuator at a high speed, the flow of fluid from the pump into the actuator is restricted by only a small amount. In contrast, to move the same or another actuator at a low speed, the restriction placed on the flow of fluid is increased. Although adequate for many applications, the use of fluid restriction to control actuator speed can result in flow losses that reduce an overall efficiency of a hydraulic system.
An alternative type of hydraulic system is known as a meterless hydraulic system. A meterless hydraulic system generally includes a pump connected in closed-loop fashion to a single actuator or to a pair of actuators operating in tandem. During operation, the pump draws fluid from one chamber of the actuator(s) and discharges pressurized fluid to an opposing chamber of the same actuator(s). To move the actuator(s) at a higher speed, the pump discharges fluid at a faster rate. To move the actuator with a lower speed, the pump discharges the fluid at a slower rate. A meterless hydraulic system is generally more efficient than a conventional hydraulic system because the speed of the actuator(s) is controlled through pump operation as opposed to fluid restriction. That is, the pump is controlled to only discharge as much fluid as is necessary to move the actuator(s) at a desired speed, and no throttling of a fluid flow is required. An exemplary meterless hydraulic system is disclosed in U.S. Patent Publication 2010/0162593 of Hughes, IV et al. that published on Jul. 1, 2010 (“the '593 publication).
Although an improvement over conventional hydraulic systems, the meterless hydraulic system of the '593 publication may still be less than optimal. In particular, the hydraulic system of the '593 publication may suffer from instabilities during transitional operations (i.e., during operations that transition between resistive and overrunning modes), pump overspeeding during operation in the overrunning mode, and/or damaging pressure spikes.
The hydraulic system of the present disclosure is directed toward solving one or more of the problems set forth above and/or other problems of the prior art. | {
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1. Related Technical Fields
Related technical fields include navigation apparatus.
2. Description of Related Art
Conventional navigation apparatuses display a route to a destination and provide timely guidance, thereby making vehicular travel easier. Thus, the use of such navigation apparatuses is increasing.
Conventional navigation apparatuses, such as, for example, described in Japanese Unexamined Patent Application Publication No. H9-178501, store a route taken in the past and uses the stored route information when searching a new route or a detour route. While traveling a route, the conventional navigation apparatuses may, for example, select a route taken in the past and set a destination based on the selected route. | {
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Digital Subscriber Line technology architectures, generally denoted as xDSL, allow digital distribution of data services with traditional narrowband voice transmissions.
One form of xDSL of particular interest to the present invention is VDSL (Very high bit rate Digital Subscriber Line), which is a packet-based transmission architecture used to provide high bandwidth distribution of digital video and data signals to customers. A VDSL-based architecture provides a single platform for supporting bandwidth-intensive applications, such as Internet access, remote LAN access, video conferencing, and video-on-demand, and is the only xDSL technology designed to handle the broadband requirements of video distribution.
VDSL services are typically implemented in an asymmetric form having a maximum downstream transmission capability of about 52 Mbps over twisted pair. Upstream data rates in asymmetric implementations tend to range up to about 3.3 Mbps. A typical VDSL distribution system includes a central office equipped with a host digital terminal (HDT) and arranged to operate as a hub between multiple video information providers (VIPs)/digital service providers (DSPs) and customer dwellings. In a fiber-to-the-neighborhood (FTTN) distribution system, optic fibers (e.g. OC-3c and OC-12c) are used to connect the HDT to a universal service access multiplexer (USAM), which is then connected to a network interface device (NID) located on the customer premises via twisted pair copper wire. A dedicated VDSL loop extends between the NID and an individual customer residence using either a dedicated twisted pair or telephone system twisted pair wire, and a customer interface device, such as a residential gateway or set top box, provides a connection point for a customer television or personal computer. A fiber-to-the-curb (FTTC) distribution system is similar except that a broadband network unit (BNU) is used in place of the USAM, and coaxial cable may be used to connect the BNU, NID, and set top box.
The VDSL signal format is used to carry signals to and from the customer. In these systems, the central office provisions each user for programming access rights, and maintains a profile database for each provisioned customer at the HDT to control the signals/channels that can be viewed by the customer.
In this environment, each of the various components and connections play a critical role in maintaining signal and network integrity. One element of particular concern involves the loop to each customer location. VDSL architectures operate at higher frequencies relative to the other xDSL technologies, and therefore require special considerations during testing to insure accurate collection of data. To date, a suitable test arrangement has yet to be developed which would allow accurate testing of a loop prior to actual provisioning of video/data service to the customer location. Because of service activation overhead and loop configuration database errors, a need exists for an economical and accurate testing process which can emphasize loop pre-qualification, noise measurement, and drop replacement. | {
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1. Field of the Invention
The present invention relates to an aqueous emulsion or dispersion type photosensitive resin composition which is highly suitable for production of printing plates, especially screen printing plates.
2. Description of the Prior Art
Various photosensitive resin compositions have been used as printing plate materials, photoresists for photo-etching and vehicles for paints and printing inks. Especially, photosensitive resin compositions as materials for printing plates are required to satisfy not only basic requirements such as high sensitivity and high resolving power but also printing resistance sufficient to resist stresses such as friction or compression under application of an oily or aqueous ink, good adhesion to a substrate and good storage stability.
Known photosensitive resin compositions to be applied to the above mentioned uses are roughly divided into the solvent development type, the aqueous alkali development type and the water development type. Most of these known photosensitive resin compositions are homogeneous photosensitive compositions, and aqueous emulsions are used in some of the water development type compositions. For example, a photosensitive resin composition comprising an aqueous emulsion of a polymer such as partially saponified polyvinyl acetate and a photo-crosslinking agent such as a dichromate or a diazo resin is used particularly for a screen printing plate.
However, such conventional aqueous emulsion type photosensitive resin compositions are also accompanied by problems in that (a) the solvent resistance of a basic polymer constituting an aqueous emulsion is insufficient, (b) since the amount of partially saponified polyvinyl acetate should be increased so as to prevent reduction of the solvent resistance of the photosensitive resin composition, the water resistance is reduced and (c) a relatively large amount of a surface active agent is used as an emulsifier for the polymer emulsion. For these reasons, cured or hardened films having excellent water resistance, solvent resistance and printing resistance cannot be prepared from the conventional aqueous emulsion type photosensitive resin compositions.
As a water-soluble, high-sensitivity photosensitive polymer having a photo-crosslinking property, there is known a polymer formed by introducing a styrylpyridinium group into a polymer chain of partially saponified polyvinyl acetate (see Japanese patent application Laid-Open Specification Nos. 23163/80 and 62905/80), and there is also known an aqueous emulsion type photosensitive resin composition formed by adding this photo-crosslinkable polymer, instead of the photo-crosslinking agent such as a dichromate or a diazo resin, to an emulsion of a polymer such as polyvinyl acetate (see Japanese patent application Laid-Open Specification No. 62446/80). A composition of this type has excellent sensitivity and storage stability, but from the results of researches we have conducted, it has been found that since an emulsified polymer is used as the main base polymer, several problems described below arise.
In the case where a hardened product obtained by using a polyvinyl acetate emulsion as a typical polymer emulsion is used for fabrication of a printing plate, this plate has insufficient oil resistance and is readily corroded by an organic solvent contained in an ink. Furthermore, the plate has insufficient water resistance, and corrosion thereof is promoted in a state where water is incorporated in the organic solvent. Moreover, at the step of mixing an emulsion such as an acrylic acid ester resin emulsion, an ethylene-acrylic acid ester copolymer resin emulsion, an SBR latex, a silicone resin emulsion, a vinyl chloride resin emulsion or a vinylidene chloride emulsion with an aqueous solution of saponified polyvinyl acetate to which a styrylpyridinium group has been added, such troubles as increase of the viscosity, gelation, dispersion fracture of the emulsion and formation of coarse particles arise. In the case of each of the foregoing emulsions, since a relatively large amount of a surface active agent is used, the solvent resistance and water resistance of the hardened product obtained are degraded by the presence of the surface active agent. | {
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A number of fields of endeavor are relevant to the present invention, and exemplary prior art, incorporated herein by reference, are disclosed below. The references disclosed provide a skilled artisan with embodiments of elements of the present invention, and the teachings therein may be combined and subcombined in various manners in accordance with the present teachings. The topical headings are advisory only, and are not intended to limit the applicability of any reference. While some embodiments are discussed as being preferred, it should be understood that all embodiments discussed, in any portion of this documents, whether stated as having advantages or not, form a part of the invention and may be combined and/or subcombined in a consistent manner in accordance with the teachings hereof.
Internet
The Internet is structured such various networks are interconnected, with communications effected by addressed packets conforming to a common protocol. Based on the packet addressing, information is routed from source to destination, often through a set of networks having multiple potential pathways. The communications medium is shared between all users. Statistically, some proportion of the packets are extraordinarily delayed, or simply lost. Therefore, protocols involving communications using these packets include error detection schemes that request a retransmit of required data not received within a time window. In the even that the network nears capacity or is otherwise subject to limiting constraint, the incidence of delayed or lost packets increases, thereby increasing requests for retransmission and retransmission. Therefore, as the network approaches available bandwidth, the load increases, ultimately leading to failure. In instances where a minimum quality of service must be guaranteed, special Internet technologies are required, to reserve bandwidth or to specify network pathways. End-to-end quality of service guarantees, however, may exceed the cost of circuit switched technologies, such as dialup modems, especially where the high quality needs are intermittent.
Internet usage typically involves an Internet server, an automated system capable of responding to communications received through the Internet, and often communicating with other systems not directly connected to the Internet. The server typically has relatively large bandwidth to the Internet, allowing multiple simultaneous communications sessions, and usually supports the hypertext transport protocol (HTTP), which provides, in conjunction with a so-called web browser on a remote client system, a human readable interface which facilitates navigation of various resources available in the Internet. The client systems are typically human user interfaces, which employ a browser to display HTTP “web pages”. The browser typically does not provide intelligence. Bandwidth between the client and Internet is typically relatively small, and various communications and display rendering considered normal. Typically, both client and server are connected to the Internet through Internet service providers, each having its own router.
It is also known to provide so-called proxy servers and firewalls, which are automated systems that insulate the client system from the Internet. Further, so-called Internet applications and applets are known which provide local intelligence at the client system. Further, it is known to provide a local server within the client system for locally processing a portion of the information. These local servers, applications and applets are non-standard, and thus require special software to be available locally for execution.
Thus, the Internet poses a number of advantages for commercial use, including low cost and ubiquitous connectivity. Therefore, it is desirable to employ standard Internet technologies while achieving sufficient quality communications to effect an efficient transaction.
Market Economy Systems
In modern retail transactions, predetermined price transactions are common, with market transactions, i.e., commerce conducted in a setting which allows the transaction price to float based on the respective valuation allocated by the buyer(s) and seller(s), often left to specialized fields. While interpersonal negotiation is often used to set a transfer price, this price is often different from a transfer price that might result from a best-efforts attempt at establishing a market price. Assuming that the market price is optimal, it is therefore assumed that alternatives are sub optimal. Therefore, the establishment of a market price is desirable over simple negotiations.
One particular problem with market-based commerce is that both seller optimization and market efficiency depend on the fact that representative participants of a preselected class are invited to participate, and are able to promptly communicate, on a relevant timescale, in order to accurately value the goods or services and make an offer. Thus, in traditional market-based system, all participants are in the same room, or connected by a high quality telecommunications link. Alternately, the market valuation process is prolonged over an extended period, allowing non-real time communications of market information and bids. Thus, attempts at ascertaining a market price for non-commodity goods can be subject to substantial inefficiencies, which reduce any potential gains by market pricing. Further, while market pricing might be considered “fair”, it also imposes an element of risk, reducing the ability of parties to predict future pricing and revenues. Addressing this risk may also reduce efficiency of a market-based system.
Auction Systems
When a single party seeks to sell goods to the highest valued purchaser(s), to establish a market price, the rules of conduct typically define an auction. Typically, known auctions provide an ascending price or descending price over time, with bidders making offers or ceasing to make offers, in the descending price or ascending price models, respectively, to define the market price. After determining the winner of the auction, the pricing rules define uniform price auctions, wherein all successful bidders pay the lowest successful bid, second price auctions wherein the winning bidder pays the amount bid by the next highest bidder, and pay-what-you-bid auctions. The pay-what-you-bid auction is also known as a discriminative auction while the uniform price auction is known as a non-discriminative auction. In a second-price auction, also known as a Vickrey auction, the policy seeks to create a disincentive for speculation and to encourage bidders to submit bids reflecting their true value for the good. In the uniform price and second price schemes, the bidder is encourages to disclose the actual private value to the bidder of the good or service, since at any price below this amount, there is an excess gain to the buyer, whereas by withholding this amount the bid may be unsuccessful, resulting in a loss of the presumably desirable opportunity. In the pay-what-you-bid auction, on the other hand, the buyer need not disclose the maximum private valuation, and those bidders with lower risk tolerance will bid higher prices. See, www.isoc.org/inet98/proceedings/3b/3b_3.html; www.ibm.com/iac/reports-technical/reports-bus-neg-internet.html.
Two common types of auction are the English auction, which sells a single good to the highest bidder in an ascending price auction, and the Dutch auction, in which multiple units are available for sale, and in which a starting price is selected by the auctioneer, which is successively reduced, until the supply is exhausted by bidders (or the minimum price/final time is reached), with the buyer(s) paying the lowest successful bid. The term Dutch auction is also applied to a type of sealed bid auction. In a multi-unit live Dutch auction, each participant is provided with the current price, the quantity on hand and the time remaining in the auction. This type of auction, typically takes place over a very short period of time and there is a flurry of activity in the last portion of the auction process. The actual auction terminates when there is no more product to be sold or the time period expires.
In selecting the optimal type of auction, a number of factors are considered. In order to sell large quantities of a perishable commodity in a short period of time, the descending price auctions are often preferred. For example, the produce and flower markets in Holland routinely use the Dutch auction (hence the derivation of the name), while the U.S. Government uses this form to sell its financial instruments. The format of a traditional Dutch auction encourages early bidders to bid up to their “private value”, hoping to pay some price below the “private value”. In making a bid, the “private value” becomes known, helping to establish a published market value and demand curve for the goods, thus allowing both buyers and sellers to define strategies for future auctions.
In an auction, typically a seller retains an auctioneer to conduct an auction with multiple buyers. (In a reverse auction, a buyer solicits the lowest price from multiple competing vendors for a desired purchase). Since the seller retains the auctioneer, the seller essentially defines the rules of the auction. These rules are typically defined to maximize the revenues or profit to the seller, while providing an inviting forum to encourage a maximum number of high valued buyers. If the rules discourage high valuations of the goods or services, or discourage participation by an important set of potential bidders, then the rules are not optimum. A rule may also be imposed to account for the valuation of the good or service applied by the seller, in the form of a reserve price. It is noted that these rules typically seek to allocate to the seller a portion of the economic benefit that would normally inure to the buyer, creating an economic inefficiency. However, since the auction is to benefit the seller, not society as a whole, this potential inefficiency is tolerated. An optimum auction thus seeks to produce a maximum profit (or net revenues) for the seller. An efficient auction, on the other hand, maximizes the sum of the utilities for the buyer and seller. It remains a subject of academic debate as to which auction rules are most optimum in given circumstances; however, in practice, simplicity of implementation may be a paramount concern, and simple auctions may result in highest revenues; complex auctions, while theoretically more optimal, may discourage bidders from participating or from applying their true and full private valuation in the auction process.
Typically, the rules of the auction are predefined and invariant. Further, for a number of reasons, auctions typically apply the same rules to all bidders, even though, with a priori knowledge of the private values assigned by each bidder to the goods, or a prediction of the private value, an optimization rule may be applied to extract the full value assigned by each bidder, while selling above the sellers reserve.
In a known ascending price auction, each participant must be made aware of the status of the auction, e.g., open, closed, and the contemporaneous price. A bid is indicated by the identification of the bidder at the contemporaneous price, or occasionally at any price above the minimum bid increment plus the previous price. The bids are asynchronous, and therefore each bidder must be immediately informed of the particulars of each bid by other bidders.
In a known descending price auction, the process traditionally entails a common clock, which corresponds to a decrementing price at each decrement interval, with an ending time (and price). Therefore, once each participant is made aware of the auction parameters, e.g., starting price, price decrement, ending price/time, before the start of the auction, the only information that must be transmitted is auction status (e.g., inventory remaining).
As stated above, an auction is traditionally considered an efficient manner of liquidating goods at a market price. The theory of an auction is that either the buyer will not resell, and thus has an internal or private valuation of the goods regardless of other's perceived values, or that the winner will resell, either to gain economic efficiency or as a part of the buyers regular business. In the later case, it is a general presumption that the resale buyers are not in attendance at the auction or are otherwise precluded from bidding, and therefore that, after the auction, there will remain demand for the goods at a price in excess of the price paid during the auction. Extinction of this residual demand results in the so-called “winner's curse”, in which the buyer can make no profit from the transaction during the auction. Since this detracts from the value of the auction as a means of conducting profitable commerce, it is of concern to both buyer and seller. In fact, experience with initial public offerings (IPOs) of stock through various means has demonstrated that by making stock available directly to all classes of potential purchasers, latent demand for a new issue is extinguished, and the stock price is likely to decline after issuance, resulting in an IPO which is characterized as “unsuccessful”. This potential for post IPO decline tempers even initial interest in the issue, resulting in a paradoxical decline in revenues from the vehicle. In other words, the “money on the table” resulting from immediate retrading of IPO shares is deemed a required aspect of the IPO process. Thus, methods that retain latent demand after IPO shares result in post IPO increases, and therefore a “successful” IPO. Therefore, where the transaction scheme anticipates demand for resale after the initial distribution, it is often important to assure a reasonable margin for resellers and limitations on direct sale to ultimate consumers.
Research into auction theory (game theory) shows that in an auction, the goal of the seller is to optimize the auction by allocating the goods inefficiently, and thus to appropriate to himself an excess gain. This inefficiency manifests itself by either withholding goods from the market or placing the goods in the wrong hands. In order to assure for the seller a maximum gain from a misallocation of the goods, restrictions on resale are imposed; otherwise, post auction trading will tend to undue the misallocation, and the anticipation of this trading will tend to control the auction pricing. The misallocation of goods imposed by the seller through restrictions allow the seller to achieve greater revenues than if free resale were permitted. It is believed that in an auction followed by perfect resale, that any mis-assignment of the goods lowers the seller's revenues below the optimum and likewise, in an auction market followed by perfect resale, it is optimal for the seller to allocate the goods to those with the highest value. Therefore, if post-auction trading is permitted, the seller will not benefit from these later gains, and the seller will obtain sub optimal revenues.
These studies, however, typically do not consider transaction costs and internal inefficiencies of the resellers, as well as the possibility of multiple classes of purchasers, or even multiple channels of distribution, which may be subject to varying controls or restrictions, and thus in a real market, such theoretical optimal allocation is unlikely. In fact, in real markets the transaction costs involved in transfer of ownership are often critical in determining a method of sale and distribution of goods. For example, it is the efficiency of sale that motivates the auction in the first place. Yet, the auction process itself may consume a substantial margin, for example 1-15% of the transaction value. To presume, even without externally imposed restrictions on resale, that all of the efficiencies of the market may be extracted by free reallocation, ignores that the motivation of the buyer is a profitable transaction, and the buyer may have fixed and variable costs on the order of magnitude of the margin. Thus, there are substantial opportunities for the seller to gain enhanced revenues by defining rules of the auction, strategically allocating inventory amount and setting reserve pricing.
Therefore, perfect resale is but a fiction created in auction (game) theory. Given this deviation from the ideal presumptions, auction theory may be interpreted to provide the seller with a motivation to misallocate or withhold based on the deviation of practice from theory, likely based on the respective transaction costs, seller's utility of the goods, and other factors not considered by the simple analyses.
A number of proposals have been made for effecting auction systems using the Internet. These systems include consumer-to-consumer, business-to-consumer, and business-to-business types. Generally, these auctions, of various types and implementations discussed further below, are conducted through Internet browsers using hypertext markup language (HTML) “web pages”, using HTTP. In some instances, such as BIDWATCH, discussed further below, an application with associated applets is provided to define a user interface instead of HTML.
As stated above, the information packets from the transaction server to client systems associated with respective bidders communicate various information regarding the status of an interactive auction during the progress thereof. The network traffic from the client systems to the transaction server is often limited to the placement of bids; however, the amount of information required to be transmitted can vary greatly, and may involve a complex dialogue of communications to complete the auction offer. Typically, Internet based auction systems have scalability issues, wherein economies of scale are not completely apparent, leading to implementation of relatively large transaction server systems to handle peak loads. When the processing power of the transaction server system is exceeded, entire system outages may occur, resulting in lost sales or diminished profits, and diminished goodwill.
In most Internet auction system implementations, there are a large quantity of simultaneous auctions, with each auction accepting tens or hundreds of bids over a timescale of hours to days. In systems where the transaction volume exceeds these scales, for example in stock and commodity exchanges, which can accommodate large numbers of transactions per second involving the same issue, a private network, or even a local area network, is employed, and the public Internet is not used as a direct communications system with the transaction server. Thus, while infrastructures are available to allow successful handling of massive transaction per second volumes, these systems typically avoid direct public Internet communications or use of some of its limiting technologies. The transaction processing limitations are often due to the finite time required to handle, e.g., open, update, and close, database records.
In business-to-business auctions, buyers seek to ensure that the population of ultimate consumers for the good or services are not present at the auction, in order to avoid the “winner's curse”, where the highest bidder in the auction cannot liquidate or work the asset at a profit. Thus, business-to-business auctions are distinct from business-to-consumer auctions. In the former, the optimization by the seller must account for the desire or directive of the seller to avoid direct retail distribution, and instead to rely on a distribution tier represented in the auction. In the latter, the seller seeks maximum revenues and to exhaust the possibilities for downstream trade in the goods or services. In fact, these types of auctions may be distinguished by various implementing rules, such as requiring sales tax resale certificates, minimum lot size quantities, preregistration or qualification, support or associated services, or limitations on the title to the goods themselves. The conduct of these auctions may also differ, in that consumer involvement typically is permissive of mistake or indecision, while in a pure business environment professionalism and decisiveness are mandated.
In many instances, psychology plays an important role in the conduct of the auction. In a live auction, bidders can see each other, and judge the tempo of the auction. In addition, multiple auctions are often conducted sequentially, so that each bidder can begin to understand the other bidder's patterns, including hesitation, bluffing, facial gestures or mannerisms. Thus, bidders often prefer live auctions to remote or automated auctions if the bidding is to be conducted strategically.
Internet Auctions
On-line electronic auction systems which allow efficient sales of products and services are well known, for example, EBAY.COM, ONSALE.COM, UBID.COM, and the like. Inverse auctions that allow efficient purchases of product are also known, establishing a market price by competition between sellers. The Internet holds the promise of further improving efficiency of auctions by reducing transaction costs and freeing the “same time-same place” limitations of traditional auctions. This is especially appropriate where the goods may be adequately described by text or images, and thus a physical examination of the goods is not required prior to bidding.
In existing Internet systems, the technological focus has been in providing an auction system that, over the course of hours to days, allow a large number of simultaneous auctions, between a large number of bidders to occur. These systems must be scalable and have high transaction throughput, while assuring database consistency and overall system reliability. Even so, certain users may selectively exploit known technological limitations and artifacts of the auction system, including non-real time updating of bidding information, especially in the final stages of an auction.
Because of existing bandwidth and technological hurdles, Internet auctions are quite different from live auctions with respect to psychological factors. Live auctions are often monitored closely by bidders, who strategically make bids, based not only on the “value” of the goods, but also on an assessment of the competition, timing, psychology, and progress of the auction. It is for this reason that so-called proxy bidding, wherein the bidder creates a preprogrammed “strategy”, usually limited to a maximum price, are disfavored. A maximum price proxy bidding system is somewhat inefficient, in that other bidders may test the proxy, seeking to increase the bid price, without actually intending to purchase, or contrarily, after testing the proxy, a bidder might give up, even below a price he might have been willing to pay. Thus, the proxy imposes inefficiency in the system that effectively increases the transaction cost.
In order to address a flurry of activity that often occurs at the end of an auction, an auction may be held open until no further bids are cleared for a period of time, even if advertised to end at a certain time. This is common to both live and automated auctions. However, this lack of determinism may upset coordinated schedules, thus impairing efficient business use of the auction system.
In order to facilitate management of bids and bidding, some of the Internet auction sites have provided non-Hypertext Markup Language (HTML) browser based software “applet” to track auctions. For example, ONSALE.COM has made available a Marimba Castanet® applet called Bidwatch to track auction progress for particular items or classes of items, and to facilitate bidding thereon. This system, however, lacks real-time performance under many circumstances, having a stated refresh period of 10 seconds, with a long latency for confirmation of a bid, due to constraints on software execution, quality of service in communications streams, and bid confirmation dialogue. Thus, it is possible to lose a bid even if an attempt was made prior to another bidder. The need to quickly enter the bid, at risk of being too late, makes the process potentially error prone.
Proxy bidding, as discussed above, is a known technique for overcoming the constraints of Internet communications and client processing limitations, since it bypasses the client and telecommunications links and may execute solely on the host system or local thereto. However, proxy bidding undermines some of the efficiencies gained by a live market.
U.S. Pat. No. 5,890,138 to Godin, et al. (Mar. 30, 1999), expressly incorporated herein by reference in its entirety, relates to an Internet auction system. The system implements a declining price auction process, removing a user from the auction process once an indication to purchase has been received. See, Rockoff, T. E., Groves, M.; “Design of an Internet-based System for Remote Dutch Auctions”, Internet Research, v 5, n 4, pp. 10-16, MCB University Press, Jan. 1, 1995.
A known computer site for auctioning a product on-line comprises at least one web server computer designed for serving a host of computer browsers and providing the browsers with the capability to participate in various auctions, where each auction is of a single product, at a specified time, with a specified number of the product available for sale. The web server cooperates with a separate database computer, separated from the web server computer by a firewall. The database computer is accessible to the web computer server computer to allow selective retrieval of product information, which includes a product description, the quantity of the product to be auctioned, a start price of the product, and an image of the product. The web server computer displays, updated during an auction, the current price of the product, the quantity of the product remaining available for purchase and the measure of the time remaining in the auction. The current price is decreased in a predetermined manner during the auction. Each user is provided with an input instructing the system to purchase the product at a displayed current price, transmitting an identification and required financial authorization for the purchase of the product, which must be confirmed within a predetermined time. In the known system, a certain fall-out rate in the actual purchase confirmation may be assumed, and therefore some overselling allowed. Further, after a purchase is indicate, the user's screen is not updated, obscuring the ultimate lowest selling price from the user. However, if the user maintains a second browser, he can continue to monitor the auction to determine whether the product could have been purchased at a lower price, and if so, fail to confirm the committed purchase and purchase the same goods at a lower price while reserving the goods to avoid risk of loss. Thus, the system is flawed, and may fail to produce an efficient transaction or optimal price.
An Internet declining price auction system may provide the ability to track the price demand curve, providing valuable marketing information. For example, in trying to determine the response at different prices, companies normally have to conduct market surveys. In contrast, with a declining price auction, substantial information regarding price and demand is immediately known. The relationship between participating bidders and average purchasers can then be applied to provide a conventional price demand curve for the particular product.
U.S. Pat. No. 5,835,896, Fisher, et al., issued Nov. 10, 1998, expressly incorporated herein by reference in its entirety, provides method and system for processing and transmitting electronic auction information over the Internet, between a central transaction server system and remote bidder terminals. Those bids are recorded by the system and the bidders are updated with the current auction status information. When appropriate, the system closes the auction from further bidding and notifies the winning bidders and losers as to the auction outcome. The transaction server posts information from a database describing a lot available for purchase, receives a plurality of bids, stored in a bid database, in response to the information, and automatically categorizes the bids as successful or unsuccessful. Each bid is validated, and an electronic mail message is sent informing the bidder of the bid status. This system employs HTTP, and thus does not automatically update remote terminal screens, requiring the e-mail notification feature.
The auction rules may be flexible, for example including Dutch-type auctions, for example by implementing a price markdown feature with scheduled price adjustments, and English-type (progressive) auctions, with price increases corresponding to successively higher bids. In the Dutch type auction, the price markdown feature may be responsive to bidding activity over time, amount of bids received, and number of items bid for. Likewise, in the progressive auction, the award price may be dependent on the quantity desired, and typically implements a lowest successful bid price rule. Bids that are below a preset maximum posted selling price are maintained in reserve by the system. If a certain sales volume is not achieved in a specified period of time, the price is reduced to liquidate demand above the price point, with the new price becoming the posted price. On the other hand, if a certain sales volume is exceeded in a specified period of time, the system may automatically increase the price. These automatic price changes allow the seller to respond quickly to market conditions while keeping the price of the merchandise as high as possible, to the seller's benefit. A “Proxy Bidding” feature allows a bidder to place a bid for the maximum amount they are willing to pay, keeping this value a secret, displaying only the amount necessary to win the item up to the amount of the currently high bids or proxy bids of other bidders. This feature allows bidders to participate in the electronic auction without revealing to the other bidders the extent to which they are willing to increase their bids, while maintaining control of their maximum bid without closely monitoring the bidding. The feature assures proxy bidders the lowest possible price up to a specified maximum without requiring frequent inquiries as to the state of the bidding.
A “Floating Closing Time” feature may also be implemented whereby the auction for a particular item is automatically closed if no new bids are received within a predetermined time interval, assuming an increasing price auction. Bidders thus have an incentive to place bids expeditiously, rather than waiting until near the anticipated close of the auction.
U.S. Pat. No. 5,905,975, Ausubel, issued May 18, 1999, expressly incorporated herein by reference in its entirety, relates to computer implemented methods and apparatus for auctions. The proposed system provides intelligent systems for the auctioneer and for the user. The auctioneer's system contains information from a user system based on bid information entered by the user. With this information, the auctioneer's system determines whether the auction can be concluded or not and appropriate messages are transmitted. At any point in the auction, bidders are provided the opportunity to submit not only their current bids, but also to enter future bids, or bidding rules which may have the opportunity to become relevant at future times or prices, into the auction system's database. Participants may revise their executory bids, by entering updated bids. Thus, at one extreme, a bidder who wishes to economize on his time may choose to enter his entire set of bidding rules into the computerized system at the start of the auction, effectively treating this as a sealed-bid auction. At the opposite extreme, a bidder who wishes to closely participate in the auction may choose to constantly monitor the auction's progress and to submit all of his bids in real time. See also, U.S. patent application Ser. No. 08/582,901 filed Jan. 4, 1996, which provides a method for auctioning multiple, identical objects and close substitutes.
Secure Networks
A number of references relate to secure networks, which are an aspect of various embodiments of the present invention. These references are incorporated herein by reference in their entirety, including U.S. Pat. No. 5,933,498 (Schneck, et al., Aug. 3, 1999); U.S. Pat. No. 5,978,918 (Scholnick, et al., Nov. 2, 1999); U.S. Pat. No. 6,005,943 (Cohen, et al., Dec. 21, 1999); U.S. Pat. No. 6,009,526 (Choi, Dec. 28, 1999); U.S. Pat. No. 6,021,202 (Anderson, et al., Feb. 1, 2000); U.S. Pat. No. 6,021,491 (Renaud, Feb. 1, 2000); U.S. Pat. No. 6,021,497 (Bouthillier, et al., Feb. 1, 2000); U.S. Pat. No. 6,023,762 (Dean, et al., Feb. 8, 2000); U.S. Pat. No. 6,029,245 (Scanlan, Feb. 22, 2000); U.S. Pat. No. 6,049,875 (Suzuki, et al., Apr. 11, 2000); U.S. Pat. No. 6,055,508 (Naor, et al., Apr. 25, 2000); U.S. Pat. No. 6,065,119 (Sandford, I I, et al., May 16, 2000); U.S. Pat. No. 6,073,240 (Kurtzberg, et al., Jun. 6, 2000); U.S. Pat. No. 6,075,860 (Ketcham, Jun. 13, 2000); and U.S. Pat. No. 6,075,861 (Miller, II, Jun. 13, 2000).
Cryptographic Technology
U.S. Pat. No. 5,956,408 (Arnold, Sep. 21, 1999), expressly incorporated herein by reference, relates to an apparatus and method for secure distribution of data. Data, including program and software updates, is encrypted by a public key encryption system using the private key of the data sender. The sender also digitally signs the data. The receiver decrypts the encrypted data, using the public key of the sender, and verifies the digital signature on the transmitted data. The program interacts with basic information stored within the confines of the receiver. As result of the interaction, the software updates are installed within the confines of the user, and the basic information stored within the confines of the user is changed.
U.S. Pat. No. 5,982,891 (Ginter, et al., Nov. 9, 1999); U.S. Pat. No. 5,949,876 (Ginter, et al., Sep. 7, 1999); and U.S. Pat. No. 5,892,900 (Ginter, et al., Apr. 6, 1999), expressly incorporated herein by reference, relate to systems and methods for secure transaction management and electronic rights protection. Electronic appliances, such as computers, help to ensure that information is accessed and used only in authorized ways, and maintain the integrity, availability, and/or confidentiality of the information. Such electronic appliances provide a distributed virtual distribution environment (VDE) that may enforce a secure chain of handling and control, for example, to control and/or meter or otherwise monitor use of electronically stored or disseminated information. Such a virtual distribution environment may be used to protect rights of various participants in electronic commerce and other electronic or electronic-facilitated transactions. Distributed and other operating systems, environments and architectures, such as, for example, those using tamper-resistant hardware-based processors, may establish security at each node. These techniques may be used to support an all-electronic information distribution, for example, utilizing the “electronic highway.”
U.S. Pat. No. 6,009,177 (Sudia, Dec. 28, 1999), expressly incorporated herein by reference, relates to a cryptographic system and method with a key escrow feature that uses a method for verifiably splitting users' private encryption keys into components and for sending those components to trusted agents chosen by the particular users, and provides a system that uses modern public key certificate management, enforced by a chip device that also self-certifies. The methods for key escrow and receiving an escrow certificate are also applied herein to a more generalized case of registering a trusted device with a trusted third party and receiving authorization from that party enabling the device to communicate with other trusted devices. Further preferred embodiments provide for rekeying and upgrading of device firmware using a certificate system, and encryption of stream-oriented data.
U.S. Pat. No. 6,052,467 (Brands, Apr. 18, 2000), expressly incorporated herein by reference, relates to a system for ensuring that the blinding of secret-key certificates is restricted, even if the issuing protocol is performed in parallel mode. A cryptographic method is disclosed that enables the issuer in a secret-key certificate issuing protocol to issue triples consisting of a secret key, a corresponding public key, and a secret-key certificate of the issuer on the public key, in such a way that receiving parties can blind the public key and the certificate, but cannot blind a predetermined non-trivial predicate of the secret key even when executions of the issuing protocol are performed in parallel.
U.S. Pat. No. 6,052,780 (Glover, Apr. 18, 2000), expressly incorporated herein by reference, relates to a computer system and process for accessing an encrypted and self-decrypting digital information product while restricting access to decrypted digital information. Some of these problems with digital information protection systems may be overcome by providing a mechanism that allows a content provider to encrypt digital information without requiring either a hardware or platform manufacturer or a content consumer to provide support for the specific form of corresponding decryption. This mechanism can be provided in a manner that allows the digital information to be copied easily for back-up purposes and to be transferred easily for distribution, but which should not permit copying of the digital information in decrypted form. In particular, the encrypted digital information is stored as an executable computer program that includes a decryption program that decrypts the encrypted information to provide the desired digital information, upon successful completion of an authorization procedure by the user. In combination with other mechanisms that track distribution, enforce royalty payments and control access to decryption keys, an improved method is provided for identifying and detecting sources of unauthorized copies. Suitable authorization procedures also enable the digital information to be distributed for a limited number of uses and/or users, thus enabling per-use fees to be charged for the digital information.
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No. 6,038,666 (Remote identity verification technique using a personal identification device); U.S. Pat. No. 6,041,122 (Method and apparatus for hiding cryptographic keys utilizing autocorrelation timing encoding and computation); U.S. Pat. No. 6,041,123 (Centralized secure communications system); U.S. Pat. No. 6,041,357 (Common session token system and protocol); U.S. Pat. No. 6,041,408 (Key distribution method and system in secure broadcast communication); U.S. Pat. No. 6,041,410 (Personal identification fob); U.S. Pat. No. 6,044,131 (Secure digital x-ray image authentication method); U.S. Pat. No. 6,044,155 (Method and system for securely archiving core data secrets); U.S. Pat. No. 6,044,157 (Microprocessor suitable for reproducing AV data while protecting the AV data from illegal copy and image information processing system using the microprocessor); U.S. Pat. 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No. 6,047,066 (Communication method and device); U.S. Pat. No. 6,047,067 (Electronic-monetary system); U.S. Pat. No. 6,047,072 (Method for secure key distribution over a nonsecure communications network); U.S. Pat. No. 6,047,242 (Computer system for protecting software and a method for protecting software); U.S. Pat. No. 6,047,268 (Method and apparatus for billing for transactions conducted over the internet); U.S. Pat. No. 6,047,269 (Self-contained payment system with circulating digital vouchers); U.S. Pat. No. 6,047,374 (Method and apparatus for embedding authentication information within digital data); U.S. Pat. No. 6,047,887 (System and method for connecting money modules); U.S. Pat. No. 6,049,610 (Method and apparatus for digital signature authentication); U.S. Pat. No. 6,049,612 (File encryption method and system); U.S. Pat. No. 6,049,613 (Method and apparatus for encrypting, decrypting, and providing privacy for data values); U.S. Pat. No. 6,049,671 (Method for identifying and obtaining computer software from a network computer); U.S. Pat. No. 6,049,785 (Open network payment system for providing for authentication of payment orders based on a confirmation electronic mail message); U.S. Pat. No. 6,049,786 (Electronic bill presentment and payment system which deters cheating by employing hashes and digital signatures); U.S. Pat. No. 6,049,787 (Electronic business transaction system with notarization database and means for conducting a notarization procedure); U.S. Pat. No. 6,049,838 (Persistent distributed capabilities); U.S. Pat. No. 6,049,872 (Method for authenticating a channel in large-scale distributed systems); U.S. Pat. No. 6,049,874 (System and method for backing up computer files over a wide area computer network); U.S. Pat. No. 6,052,466 (Encryption of data packets using a sequence of private keys generated from a public key exchange); U.S. Pat. No. 6,052,467 (System for ensuring that the blinding of secret-key certificates is restricted, even if the issuing protocol is performed in parallel mode); U.S. Pat. No. 6,052,469 (Interoperable cryptographic key recovery system with verification by comparison); U.S. Pat. No. 6,055,314 (System and method for secure purchase and delivery of video content programs); U.S. Pat. No. 6,055,321 (System and method for hiding and extracting message data in multimedia data); U.S. Pat. No. 6,055,508 (Method for secure accounting and auditing on a communications network); U.S. Pat. No. 6,055,512 (Networked personal customized information and facility services); U.S. Pat. No. 6,055,636 (Method and apparatus for centralizing processing of key and certificate life cycle management); U.S. Pat. No. 6,055,639 (Synchronous message control system in a Kerberos domain); U.S. Pat. No. 6,056,199 (Method and apparatus for storing and reading data); U.S. Pat. No. 6,057,872 (Digital coupons for pay televisions); U.S. Pat. No. 6,058,187 (Secure telecommunications data transmission); U.S. Pat. No. 6,058,188 (Method and apparatus for interoperable validation of key recovery information in a cryptographic system); U.S. Pat. No. 6,058,189 (Method and system for performing secure electronic monetary transactions); U.S. Pat. No. 6,058,193 (System and method of verifying cryptographic postage evidencing using a fixed key set); U.S. Pat. No. 6,058,381 (Many-to-many payments system for network content materials); U.S. Pat. No. 6,058,383 (Computationally efficient method for trusted and dynamic digital objects dissemination); U.S. Pat. No. 6,061,448 (Method and system for dynamic server document encryption); U.S. Pat. No. 6,061,454 (System, method, and computer program for communicating a key recovery block to enable third party monitoring without modification to the intended receiver); U.S. Pat. No. 6,061,692 (System and method for administering a meta database as an integral component of an information server); U.S. Pat. No. 6,061,789 (Secure anonymous information exchange in a network); U.S. Pat. No. 6,061,790 (Network computer system with remote user data encipher methodology); U.S. Pat. No. 6,061,791 (Initial secret key establishment including facilities for verification of identity); U.S. Pat. No. 6,061,792 (System and method for fair exchange of time-independent information goods over a network); U.S. Pat. No. 6,061,794 (System and method for performing secure device communications in a peer-to-peer bus architecture); U.S. Pat. No. 6,061,796 (Multi-access virtual private network); U.S. Pat. No. 6,061,799 (Removable media for password based authentication in a distributed system); U.S. Pat. No. 6,064,723 (Network-based multimedia communications and directory system and method of operation); U.S. Pat. No. 6,064,738 (Method for encrypting and decrypting data using chaotic maps); U.S. Pat. No. 6,064,740 (Method and apparatus for masking modulo exponentiation calculations in an integrated circuit); U.S. Pat. No. 6,064,741 (Method for the computer-aided exchange of cryptographic keys between a user computer unit U and a network computer unit N); U.S. Pat. No. 6,064,764 (Fragile watermarks for detecting tampering in images); U.S. Pat. No. 6,064,878 (Method for separately permissioned communication); U.S. Pat. No. 6,065,008 (System and method for secure font subset distribution); U.S. Pat. No. 6,067,620 (Stand alone security device for computer networks); U.S. Pat. No. 6,069,647 (Conditional access and content security method); U.S. Pat. No. 6,069,952 (Data copyright management system); U.S. Pat. No. 6,069,954 (Cryptographic data integrity with serial bit processing and pseudo-random generators); U.S. Pat. No. 6,069,955 (System for protection of goods against counterfeiting); U.S. Pat. No. 6,069,969 (Apparatus and method for electronically acquiring fingerprint images); U.S. Pat. No. 6,069,970 (Fingerprint sensor and token reader and associated methods); U.S. Pat. No. 6,070,239 (System and method for executing verifiable programs with facility for using non-verifiable programs from trusted sources); U.S. Pat. No. 6,072,870 (System, method and article of manufacture for a gateway payment architecture utilizing a multichannel, extensible, flexible architecture); U.S. Pat. No. 6,072,874 (Signing method and apparatus using the same); U.S. Pat. No. 6,072,876 (Method and system for depositing private key used in RSA cryptosystem); U.S. Pat. No. 6,073,125 (Token key distribution system controlled acceptance mail payment and evidencing system); U.S. Pat. No. 6,073,160 (Document communications controller); U.S. Pat. No. 6,073,172 (Initializing and reconfiguring a secure network interface); U.S. Pat. No. 6,073,234 (Device for authenticating user's access rights to resources and method); U.S. Pat. No. 6,073,236 (Authentication method, communication method, and information processing apparatus); U.S. Pat. No. 6,073,237 (Tamper resistant method and apparatus); U.S. Pat. No. 6,073,238 (Method of securely loading commands in a smart card); U.S. Pat. No. 6,073,242 (Electronic authority server); U.S. Pat. No. 6,075,864 (Method of establishing secure, digitally signed communications using an encryption key based on a blocking set cryptosystem); U.S. Pat. No. 6,075,865 (Cryptographic communication process and apparatus); U.S. Pat. No. 6,076,078 (Anonymous certified delivery); U.S. Pat. No. 6,076,162 (Certification of cryptographic keys for chipcards); U.S. Pat. No. 6,076,163 (Secure user identification based on constrained polynomials); U.S. Pat. No. 6,076,164 (Authentication method and system using IC card); U.S. Pat. No. 6,076,167 (Method and system for improving security in network applications); U.S. Pat. No. 6,078,663 (Communication apparatus and a communication system); U.S. Pat. No. 6,078,665 (Electronic encryption device and method); U.S. Pat. No. 6,078,667 (Generating unique and unpredictable values); U.S. Pat. No. 6,078,909 (Method and apparatus for licensing computer programs using a DSA signature); U.S. Pat. No. 6,079,018 (System and method for generating unique secure values for digitally signing documents); U.S. Pat. No. 6,079,047 (Unwrapping system and method for multiple files of a container); U.S. Pat. No. 6,081,597 (Public key cryptosystem method and apparatus); U.S. Pat. No. 6,081,598 (Cryptographic system and method with fast decryption); U.S. Pat. No. 6,081,610 (System and method for verifying signatures on documents); U.S. Pat. No. 6,081,790 (System and method for secure presentment and payment over open networks); U.S. Pat. No. 6,081,893 (System for supporting secured log-in of multiple users into a plurality of computers using combined presentation of memorized password and transportable passport record), U.S. Pat. No. 6,192,473 (System and method for mutual authentication and secure communications between a postage security device and a meter server), each of which is expressly incorporated herein by reference.
See, also, U.S. Pat. No. 6,028,937 (Tatebayashi et al.), U.S. Pat. No. 6,026,167 (Aziz), U.S. Pat. No. 6,009,171 (Ciacelli et al.) (Content Scrambling System, or “CSS”), U.S. Pat. No. 5,991,399 (Graunke et al.), U.S. Pat. No. 5,948,136 (Smyers) (IEEE 1394-1995), and U.S. Pat. No. 5,915,018 (Aucsmith), expressly incorporated herein by reference, and Jim Wright and Jeff Robillard (Philsar Semiconductor), “Adding Security to Portable Designs”, Portable Design, March 2000, pp. 16-20.
See also, Stefik, U.S. Pat. No. 5,715,403 (System for controlling the distribution and use of digital works having attached usage rights where the usage rights are defined by a usage rights grammar); U.S. Pat. No. 5,638,443 (System for controlling the distribution and use of composite digital works); U.S. Pat. No. 5,634,012 (System for controlling the distribution and use of digital works having a fee reporting mechanism); and U.S. Pat. No. 5,629,980 (System for controlling the distribution and use of digital works), expressly incorporated herein by reference.
Watermarking
U.S. Pat. No. 5,699,427 (Chow, et al., Dec. 16, 1997), expressly incorporated herein by reference, relates to a method to deter document and intellectual property piracy through individualization, and a system for identifying the authorized receiver of any particular copy of a document. More specifically, each particular copy of a document is fingerprinted by applying a set of variations to a document, where each variation is a change in data contents, but does not change the meaning or perusal experience of the document. A database associating a set of variants to a receiver is maintained. Thus any variant or copy of that variant can be traced to an authorized receiver.
See also, U.S. Pat. No. 4,734,564 (Transaction system with off-line risk assessment); U.S. Pat. No. 4,812,628 (Transaction system with off-line risk assessment); U.S. Pat. No. 4,926,325 (Apparatus for carrying out financial transactions via a facsimile machine); U.S. Pat. No. 5,235,166 (Data verification method and magnetic media therefor); U.S. Pat. No. 5,254,843 (Securing magnetically encoded data using timing variations in encoded data); U.S. Pat. No. 5,341,429 (Transformation of ephemeral material); U.S. Pat. No. 5,428,683 (Method and apparatus for fingerprinting and authenticating magnetic media); U.S. Pat. No. 5,430,279 (Data verification method and magnetic media therefor); U.S. Pat. No. 5,521,722 (Image handling facilitating computer aided design and manufacture of documents); U.S. Pat. No. 5,546,462 (Method and apparatus for fingerprinting and authenticating various magnetic media); U.S. Pat. No. 5,606,609 (Electronic document verification system and method); U.S. Pat. No. 5,613,004 (Steganographic method and device); U.S. Pat. No. 5,616,904 (Data verification method and magnetic media therefor); U.S. Pat. No. 5,636,292 (Steganography methods employing embedded calibration data); U.S. Pat. No. 5,646,997 (Method and apparatus for embedding authentication information within digital data); U.S. Pat. No. 5,659,726 (Data embedding); U.S. Pat. No. 5,664,018 (Watermarking process resilient to collusion attacks); U.S. Pat. No. 5,687,236 (Steganographic method and device); U.S. Pat. No. 5,710,834 (Method and apparatus responsive to a code signal conveyed through a graphic image); U.S. Pat. No. 5,727,092 (Compression embedding); U.S. Pat. No. 5,734,752 (Digital watermarking using stochastic screen patterns); U.S. Pat. No. 5,740,244 (Method and apparatus for improved fingerprinting and authenticating various magnetic media); U.S. Pat. No. 5,745,569 (Method for stega-cipher protection of computer code); U.S. Pat. No. 5,745,604 (Identification/authentication system using robust, distributed coding); U.S. Pat. No. 5,748,763 (Image steganography system featuring perceptually adaptive and globally scalable signal embedding); U.S. Pat. No. 5,748,783 (Method and apparatus for robust information coding); U.S. Pat. No. 5,761,686 (Embedding encoded information in an iconic version of a text image); U.S. Pat. No. 5,765,152 (System and method for managing copyrighted electronic media); U.S. Pat. No. 5,768,426 (Graphics processing system employing embedded code signals); U.S. Pat. No. 5,778,102 (Compression embedding); U.S. Pat. No. 5,790,703 (Digital watermarking using conjugate halftone screens); U.S. Pat. No. 5,819,289 (Data embedding employing degenerate clusters of data having differences less than noise value); U.S. Pat. No. 5,822,432 (Method for human-assisted random key generation and application for digital watermark system); U.S. Pat. No. 5,822,436 (Photographic products and methods employing embedded information); U.S. Pat. No. 5,832,119 (Methods for controlling systems using control signals embedded in empirical data); U.S. Pat. No. 5,841,886 (Security system for photographic identification); U.S. Pat. No. 5,841,978 (Network linking method using steganographically embedded data objects); U.S. Pat. No. 5,848,155 (Spread spectrum watermark for embedded signalling); U.S. Pat. No. 5,850,481 (Steganographic system); U.S. Pat. No. 5,862,260 (Methods for surveying dissemination of proprietary empirical data); U.S. Pat. No. 5,878,137 (Method for obtaining authenticity identification devices for using services in general, and device obtained thereby); U.S. Pat. No. 5,889,868 (Optimization methods for the insertion, protection, and detection of digital watermarks in digitized data); U.S. Pat. No. 5,892,900 (Systems and methods for secure transaction management and electronic rights protection); U.S. Pat. No. 5,905,505 (Method and system for copy protection of on-screen display of text); U.S. Pat. No. 5,905,800 (Method and system for digital watermarking); U.S. Pat. No. 5,915,027 (Digital watermarking); U.S. Pat. No. 5,920,628 (Method and apparatus for fingerprinting and authenticating various magnetic media); U.S. Pat. No. 5,930,369 (Secure spread spectrum watermarking for multimedia data); U.S. Pat. No. 5,933,498 (System for controlling access and distribution of digital property); U.S. Pat. No. 5,943,422 (Steganographic techniques for securely delivering electronic digital rights management control information over insecure communication channels); U.S. Pat. No. 5,946,414 (Encoding data in color images using patterned color modulated image regions); U.S. Pat. No. 5,949,885 (Method for protecting content using watermarking); U.S. Pat. No. 5,974,548 (Media-independent document security method and apparatus); U.S. Pat. No. 5,995,625 (Electronic cryptographic packing); U.S. Pat. No. 6,002,772 (Data management system); U.S. Pat. No. 6,004,276 (Open architecture cardiology information system); U.S. Pat. No. 6,006,328 (Computer software authentication, protection, and security system); U.S. Pat. No. 6,006,332 (Rights management system for digital media); U.S. Pat. No. 6,018,801 (Method for authenticating electronic documents on a computer network); U.S. Pat. No. 6,026,193 (Video steganography); U.S. Pat. No. 6,044,464 (Method of protecting broadcast data by fingerprinting a common decryption function); U.S. Pat. No. 6,047,374 (Method and apparatus for embedding authentication information within digital data); U.S. Pat. No. 6,049,627 (Covert digital identifying indicia for digital image); U.S. Pat. No. 6,061,451 (Apparatus and method for receiving and decrypting encrypted data and protecting decrypted data from illegal use); U.S. Pat. No. 6,064,737 (Anti-piracy system for wireless telephony); U.S. Pat. No. 6,064,764 (Fragile watermarks for detecting tampering in images); U.S. Pat. No. 6,069,914 (Watermarking of image data using MPEG/JPEG coefficients); U.S. Pat. No. 6,076,077 (Data management system); U.S. Pat. No. 6,081,793 (Method and system for secure computer moderated voting), each of which is expressly incorporated herein by reference.
Role-Based Access
U.S. Pat. No. 6,023,765 (Kuhn, Feb. 8, 2000; Implementation of role-based access control in multi-level secure systems), expressly incorporated herein by reference, relates to a system and method for implementation of role-based access control in multi-level secure systems. Role-based access control (RBAC) is implemented on a multi-level secure (MLS) system by establishing a relationship between privileges within the RBAC system and pairs of levels and compartments within the MLS system. The advantages provided by RBAC, that is, reducing the overall number of connections that must be maintained, and, for example, greatly simplifying the process required in response to a change of job status of individuals within an organization, are then realized without loss of the security provided by MLS. A trusted interface function is developed to ensure that the RBAC rules permitting individual's access to objects are followed rigorously, and provides a proper mapping of the roles to corresponding pairs of levels and compartments. No other modifications are necessary. Access requests from subjects are mapped by the interface function to pairs of levels and compartments, after which access is controlled entirely by the rules of the MLS system.
See also, U.S. Pat. No. 6,073,242 (Electronic authority server); U.S. Pat. No. 6,073,240 (Method and apparatus for realizing computer security); U.S. Pat. No. 6,064,977 (Web server with integrated scheduling and calendaring); U.S. Pat. No. 6,055,637 (System and method for accessing enterprise-wide resources by presenting to the resource a temporary credential); U.S. Pat. No. 6,044,466 (Flexible and dynamic derivation of permissions); U.S. Pat. No. 6,041,349 (System management/network correspondence display method and system therefore); U.S. Pat. No. 6,014,666 (Declarative and programmatic access control of component-based server applications using roles); U.S. Pat. No. 5,991,877 (Object-oriented trusted application framework); U.S. Pat. No. 5,978,475 (Event auditing system); U.S. Pat. No. 5,949,866 (Communications system for establishing a communication channel on the basis of a functional role or task); U.S. Pat. No. 5,925,126 (Method for security shield implementation in computer system's software); U.S. Pat. No. 5,911,143 (Method and system for advanced role-based access control in distributed and centralized computer systems); U.S. Pat. No. 5,797,128 (System and method for implementing a hierarchical policy for computer system administration); U.S. Pat. No. 5,761,288 (Service context sensitive features and applications); U.S. Pat. No. 5,751,909 (Database system with methods for controlling object interaction by establishing database contracts between objects); U.S. Pat. No. 5,748,890 (Method and system for authenticating and auditing access by a user to non-natively secured applications); U.S. Pat. No. 5,621,889 (Facility for detecting intruders and suspect callers in a computer installation and a security system including such a facility); U.S. Pat. No. 5,535,383 (Database system with methods for controlling object interaction by establishing database contracts between objects); U.S. Pat. No. 5,528,516 (Apparatus and method for event correlation and problem reporting); U.S. Pat. No. 5,481,613 (Computer network cryptographic key distribution system); U.S. Pat. No. 5,347,578 (Computer system security); U.S. Pat. No. 5,265,221 (Access restriction facility method and apparatus), each of which is expressly incorporated herein by reference.
Computer System Security
A number of references relate to computer system security, which is a part of various embodiment of the invention. The following references relevant to this issue are incorporated herein by reference: U.S. Pat. No. 5,881,225 (Worth, Mar. 9, 1999); U.S. Pat. No. 5,937,068 (Audebert, Aug. 10, 1999); U.S. Pat. No. 5,949,882 (Angelo, Sep. 7, 1999); U.S. Pat. No. 5,953,419 (Lohstroh, et al., Sep. 14, 1999); U.S. Pat. No. 5,956,400 (Chaum, et al., Sep. 21, 1999); U.S. Pat. No. 5,958,050 (Griffin, et al., Sep. 28, 1999); U.S. Pat. No. 5,978,475 (Schreier, et al., Nov. 2, 1999); U.S. Pat. No. 5,991,878 (McDonough, et al., Nov. 23, 1999); U.S. Pat. No. 6,070,239 (McManis, May 30, 2000); and U.S. Pat. No. 6,079,021 (Abadi, et al., Jun. 20, 2000).
Computer Security Devices
A number of references relate to computer security devices, which is a part of various embodiment of the invention. The following references relevant to this issue are incorporated herein by reference: U.S. Pat. No. 5,982,520 (Weiser, et al., Nov. 9, 1999); U.S. Pat. No. 5,991,519 (Benhammou, et al., Nov. 23, 1999); U.S. Pat. No. 5,999,629 (Heer, et al., Dec. 7, 1999); U.S. Pat. No. 6,034,618 (Tatebayashi, et al., Mar. 7, 2000); U.S. Pat. No. 6,041,412 (Timson, et al., Mar. 21, 2000); U.S. Pat. No. 6,061,451 (Muratani, et al., May 9, 2000); and U.S. Pat. No. 6,069,647 (Sullivan, et al., May 30, 2000).
Virtual Private Network
A number of references relate to virtual private networks, which is a part of various embodiment of the invention. The following references relevant to this issue are incorporated herein by reference: U.S. Pat. No. 6,079,020 (Liu, Jun. 20, 2000); U.S. Pat. No. 6,081,900 (Secure intranet access); U.S. Pat. No. 6,081,533 (Method and apparatus for an application interface module in a subscriber terminal unit); U.S. Pat. No. 6,079,020 (Method and apparatus for managing a virtual private network); U.S. Pat. No. 6,078,946 (System and method for management of connection oriented networks); U.S. Pat. No. 6,078,586 (ATM virtual private networks); U.S. Pat. No. 6,075,854 (Fully flexible routing service for an advanced intelligent network); U.S. Pat. No. 6,075,852 (Telecommunications system and method for processing call-independent signalling transactions); U.S. Pat. No. 6,073,172 (Initializing and reconfiguring a secure network interface); U.S. Pat. No. 6,061,796 (Multi-access virtual private network); U.S. Pat. No. 6,061,729 (Method and system for communicating service information in an advanced intelligent network); U.S. Pat. No. 6,058,303 (System and method for subscriber activity supervision); U.S. Pat. No. 6,055,575 (Virtual private network system and method); U.S. Pat. No. 6,052,788 (Firewall providing enhanced network security and user transparency); U.S. Pat. No. 6,047,325 (Network device for supporting construction of virtual local area networks on arbitrary local and wide area computer networks); U.S. Pat. No. 6,032,118 (Virtual private network service provider for asynchronous transfer mode network); U.S. Pat. No. 6,029,067 (Virtual private network for mobile subscribers); U.S. Pat. No. 6,016,318 (Virtual private network system over public mobile data network and virtual LAN); U.S. Pat. No. 6,009,430 (Method and system for provisioning databases in an advanced intelligent network); U.S. Pat. No. 6,005,859 (Proxy VAT-PSTN origination); U.S. Pat. No. 6,002,767 (System, method and article of manufacture for a modular gateway server architecture); U.S. Pat. No. 6,002,756 (Method and system for implementing intelligent telecommunication services utilizing self-sustaining, fault-tolerant object oriented architecture), each of which is expressly incorporated herein by reference.
See also, U.S. Pat. No. 6,081,900 (Secure intranet access); U.S. Pat. No. 6,081,750 (Ergonomic man-machine interface incorporating adaptive pattern recognition based control system); U.S. Pat. No. 6,081,199 (Locking device for systems access to which is time-restricted); U.S. Pat. No. 6,079,621 (Secure card for E-commerce and identification); U.S. Pat. No. 6,078,265 (Fingerprint identification security system); U.S. Pat. No. 6,076,167 (Method and system for improving security in network applications); U.S. Pat. No. 6,075,455 (Biometric time and attendance system with epidermal topographical updating capability); U.S. Pat. No. 6,072,894 (Biometric face recognition for applicant screening); U.S. Pat. No. 6,070,141 (System and method of assessing the quality of an identification transaction using an identification quality score); U.S. Pat. No. 6,068,184 (Security card and system for use thereof); U.S. Pat. No. 6,064,751 (Document and signature data capture system and method); U.S. Pat. No. 6,056,197 (Information recording method for preventing alteration, information recording apparatus, and information recording medium); U.S. Pat. No. 6,052,468 (Method of securing a cryptographic key); U.S. Pat. No. 6,045,039 (Cardless automated teller transactions); U.S. Pat. No. 6,044,349 (Secure and convenient information storage and retrieval method and apparatus); U.S. Pat. No. 6,044,155 (Method and system for securely archiving core data secrets); U.S. Pat. No. 6,041,410 (Personal identification fob); U.S. Pat. No. 6,040,783 (System and method for remote, wireless positive identity verification); U.S. Pat. No. 6,038,666 (Remote identity verification technique using a personal identification device); U.S. Pat. No. 6,038,337 (Method and apparatus for object recognition); U.S. Pat. No. 6,038,315 (Method and system for normalizing biometric variations to authenticate users from a public database and that ensures individual biometric data privacy); U.S. Pat. No. 6,037,870 (Detector system for access control, and a detector assembly for implementing such a system); U.S. Pat. No. 6,035,406 (Plurality-factor security system); U.S. Pat. No. 6,035,402 (Virtual certificate authority); U.S. Pat. No. 6,035,398 (Cryptographic key generation using biometric data); U.S. Pat. No. 6,031,910 (Method and system for the secure transmission and storage of protectable information); U.S. Pat. No. 6,026,166 (Digitally certifying a user identity and a computer system in combination); U.S. Pat. No. 6,018,739 (Biometric personnel identification system); U.S. Pat. No. 6,016,476 (Portable information and transaction processing system and method utilizing biometric authorization and digital certificate security); U.S. Pat. No. 6,012,049 (System for performing financial transactions using a smartcard); U.S. Pat. No. 6,012,039 (Tokenless biometric electronic rewards system); U.S. Pat. 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No. 5,889,474 (Method and apparatus for transmitting subject status information over a wireless communications network); U.S. Pat. No. 5,881,226 (Computer security system); U.S. Pat. No. 5,878,144 (Digital certificates containing multimedia data extensions); U.S. Pat. No. 5,876,926 (Method, apparatus and system for verification of human medical data); U.S. Pat. No. 5,875,108 (Ergonomic man-machine interface incorporating adaptive pattern recognition based control system); U.S. Pat. No. 5,872,849 (Enhanced cryptographic system and method with key escrow feature); U.S. Pat. No. 5,872,848 (Method and apparatus for witnessed authentication of electronic documents); U.S. Pat. No. 5,872,834 (Telephone with biometric sensing device); U.S. Pat. No. 5,870,723 (Tokenless biometric transaction authorization method and system); U.S. Pat. No. 5,869,822 (Automated fingerprint identification system); U.S. Pat. No. 5,867,802 (Biometrically secured control system for preventing the unauthorized use of a vehicle); U.S. Pat. No. 5,867,795 (Portable electronic device with transceiver and visual image display); U.S. Pat. No. 5,867,578 (Adaptive multi-step digital signature system and method of operation thereof); U.S. Pat. No. 5,862,260 (Methods for surveying dissemination of proprietary empirical data); U.S. Pat. No. 5,862,246 (Knuckle profile identity verification system); U.S. Pat. No. 5,862,223 (Method and apparatus for a cryptographically-assisted commercial network system designed to facilitate and support expert-based commerce); U.S. Pat. No. 5,857,022 (Enhanced cryptographic system and method with key escrow feature); U.S. Pat. No. 5,850,451 (Enhanced cryptographic system and method with key escrow feature); U.S. Pat. No. 5,850,442 (Secure world wide electronic commerce over an open network); U.S. Pat. No. 5,848,231 (System configuration contingent upon secure input); U.S. Pat. No. 5,844,244 (Portable identification carrier); U.S. Pat. No. 5,841,907 (Spatial integrating optical correlator for verifying the authenticity of a person, product or thing); U.S. Pat. No. 5,841,886 (Security system for photographic identification); U.S. Pat. No. 5,841,865 (Enhanced cryptographic system and method with key escrow feature); U.S. Pat. No. 5,841,122 (Security structure with electronic smart card access thereto with transmission of power and data between the smart card and the smart card reader performed capacitively or inductively); U.S. Pat. No. 5,838,812 (Tokenless biometric transaction authorization system); U.S. Pat. No. 5,832,464 (System and method for efficiently processing payments via check and electronic funds transfer); U.S. Pat. No. 5,832,119 (Methods for controlling systems using control signals embedded in empirical data); U.S. Pat. No. 5,828,751 (Method and apparatus for secure measurement certification); U.S. Pat. No. 5,825,880 (Multi-step digital signature method and system); U.S. Pat. No. 5,825,871 (Information storage device for storing personal identification information); U.S. Pat. No. 5,815,577 (Methods and apparatus for securely encrypting data in conjunction with a personal computer); U.S. Pat. No. 5,815,252 (Biometric identification process and system utilizing multiple parameters scans for reduction of false negatives); U.S. Pat. No. 5,805,719 (Tokenless identification of individuals); U.S. Pat. No. 5,802,199 (Use sensitive identification system); U.S. Pat. No. 5,799,088 (Non-deterministic public key encryption system); U.S. Pat. No. 5,799,086 (Enhanced cryptographic system and method with key escrow feature); U.S. Pat. No. 5,799,083 (Event verification system); U.S. Pat. No. 5,790,674 (System and method of providing system integrity and positive audit capabilities to a positive identification system); U.S. Pat. No. 5,790,668 (Method and apparatus for securely handling data in a database of biometrics and associated data); U.S. Pat. No. 5,789,733 (Smart card with contactless optical interface); U.S. Pat. No. 5,787,187 (Systems and methods for biometric identification using the acoustic properties of the ear canal); U.S. Pat. No. 5,784,566 (System and method for negotiating security services and algorithms for communication across a computer network); U.S. Pat. No. 5,784,461 (Security system for controlling access to images and image related services); U.S. Pat. No. 5,774,551 (Pluggable account management interface with unified login and logout and multiple user authentication services); U.S. Pat. No. 5,771,071 (Apparatus for coupling multiple data sources onto a printed document); U.S. Pat. No. 5,770,849 (Smart card device with pager and visual image display); U.S. Pat. No. 5,768,382 (Remote-auditing of computer generated outcomes and authenticated billing and access control system using cryptographic and other protocols); U.S. Pat. No. 5,767,496 (Apparatus for processing symbol-encoded credit card information); U.S. Pat. No. 5,764,789 (Tokenless biometric ATM access system); U.S. Pat. No. 5,763,862 (Dual card smart card reader); U.S. Pat. No. 5,761,298 (Communications headset with universally adaptable receiver and voice transmitter); U.S. Pat. No. 5,757,916 (Method and apparatus for authenticating the location of remote users of networked computing systems); U.S. Pat. No. 5,757,431 (Apparatus for coupling multiple data sources onto a printed document); U.S. Pat. No. 5,751,836 (Automated, non-invasive iris recognition system and method); U.S. Pat. No. 5,751,809 (Apparatus and method for securing captured data transmitted between two sources); U.S. Pat. No. 5,748,738 (System and method for electronic transmission, storage and retrieval of authenticated documents); U.S. Pat. No. 5,745,573 (System and method for controlling access to a user secret); U.S. Pat. No. 5,745,555 (System and method using personal identification numbers and associated prompts for controlling unauthorized use of a security device and unauthorized access to a resource); U.S. Pat. No. 5,742,685 (Method for verifying an identification card and recording verification of same); U.S. Pat. No. 5,742,683 (System and method for managing multiple users with different privileges in an open metering system); U.S. Pat. No. 5,737,420 (Method for secure data transmission between remote stations); U.S. Pat. No. 5,734,154 (Smart card with integrated reader and visual image display); U.S. Pat. No. 5,719,950 (Biometric, personal authentication system); U.S. Pat. No. 5,712,914 (Digital certificates containing multimedia data extensions); U.S. Pat. No. 5,712,912 (Method and apparatus for securely handling a personal identification number or cryptographic key using biometric techniques); U.S. Pat. No. 5,706,427 (Authentication method for networks); U.S. Pat. No. 5,703,562 (Method for transferring data from an unsecured computer to a secured computer); U.S. Pat. No. 5,696,827 (Secure cryptographic methods for electronic transfer of information); U.S. Pat. No. 5,682,142 (Electronic control system/network); U.S. Pat. No. 5,682,032 (Capacitively coupled identity verification and escort memory apparatus); U.S. Pat. No. 5,680,460 (Biometric controlled key generation); U.S. Pat. No. 5,668,878 (Secure cryptographic methods for electronic transfer of information); U.S. Pat. No. 5,666,400 (Intelligent recognition); U.S. Pat. No. 5,659,616 (Method for securely using digital signatures in a commercial cryptographic system); U.S. Pat. No. 5,647,364 (Ultrasonic biometric imaging and identity verification system); U.S. Pat. No. 5,647,017 (Method and system for the verification of handwritten signatures); U.S. Pat. No. 5,646,839 (Telephone-based personnel tracking system); U.S. Pat. No. 5,636,282 (Method for dial-in access security using a multimedia modem); U.S. Pat. No. 5,633,932 (Apparatus and method for preventing disclosure through user-authentication at a printing node); U.S. Pat. No. 5,615,277 (Tokenless security system for authorizing access to a secured computer system); U.S. Pat. No. 5,613,012 (Tokenless identification system for authorization of electronic transactions and electronic transmissions); U.S. Pat. No. 5,608,387 (Personal identification devices and access control systems); U.S. Pat. No. 5,594,806 (Knuckle profile identity verification system); U.S. Pat. No. 5,592,408 (Identification card and access control device); U.S. Pat. No. 5,588,059 (Computer system and method for secure remote communication sessions); U.S. Pat. No. 5,586,171 (Selection of a voice recognition data base responsive to video data); U.S. Pat. No. 5,583,950 (Method and apparatus for flash correlation); U.S. Pat. No. 5,583,933 (Method and apparatus for the secure communication of data); U.S. Pat. No. 5,578,808 (Data card that can be used for transactions involving separate card issuers); U.S. Pat. No. 5,572,596 (Automated, non-invasive iris recognition system and method); U.S. Pat. No. 5,561,718 (Classifying faces); U.S. Pat. No. 5,559,885 (Two stage read-write method for transaction cards); U.S. Pat. No. 5,557,765 (System and method for data recovery); U.S. Pat. No. 5,553,155 (Low cost method employing time slots for thwarting fraud in the periodic issuance of food stamps, unemployment benefits or other governmental human services); U.S. Pat. No. 5,544,255 (Method and system for the capture, storage, transport and authentication of handwritten signatures); U.S. Pat. No. 5,534,855 (Method and system for certificate based alias detection); U.S. Pat. No. 5,533,123 (Programmable distributed personal security); U.S. Pat. No. 5,526,428 (Access control apparatus and method); U.S. Pat. No. 5,523,739 (Metal detector for control of access combined in an integrated form with a transponder detector); U.S. Pat. No. 5,497,430 (Method and apparatus for image recognition using invariant feature signals); U.S. Pat. No. 5,485,519 (Enhanced security for a secure token code); U.S. Pat. No. 5,485,312 (Optical pattern recognition system and method for verifying the authenticity of a person, product or thing); U.S. Pat. No. 5,483,601 (Apparatus and method for biometric identification using silhouette and displacement images of a portion of a person's hand); U.S. Pat. No. 5,478,993 (Process as safety concept against unauthorized use of a payment instrument in cashless payment at payment sites); U.S. Pat. No. 5,475,839 (Method and structure for securing access to a computer system); U.S. Pat. No. 5,469,506 (Apparatus for verifying an identification card and identifying a person by means of a biometric characteristic); U.S. Pat. No. 5,457,747 (Anti-fraud verification system using a data card); U.S. Pat. No. 5,455,407 (Electronic-monetary system); U.S. Pat. No. 5,453,601 (Electronic-monetary system); U.S. Pat. No. 5,448,045 (System for protecting computers via intelligent tokens or smart cards); U.S. Pat. No. 5,432,864 (Identification card verification system); U.S. Pat. No. 5,414,755 (System and method for passive voice verification in a telephone network); U.S. Pat. No. 5,412,727 (Anti-fraud voter registration and voting system using a data card); U.S. Pat. No. 5,363,453 (Non-minutiae automatic fingerprint identification system and methods); U.S. Pat. No. 5,347,580 (Authentication method and system with a smartcard); U.S. Pat. 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No. 4,896,363 (Apparatus and method for matching image characteristics such as fingerprint minutiae); U.S. Pat. No. 4,890,323 (Data communication systems and methods); U.S. Pat. No. 4,868,376 (Intelligent portable interactive personal data system); U.S. Pat. No. 4,827,518 (Speaker verification system using integrated circuit cards); U.S. Pat. No. 4,819,267 (Solid state key for controlling access to computer systems and to computer software and/or for secure communications); U.S. Pat. No. 4,752,676 (Reliable secure, updatable “cash” card system); U.S. Pat. No. 4,736,203 (3D hand profile identification apparatus); U.S. Pat. No. 4,731,841 (Field initialized authentication system for protective security of electronic information networks); U.S. Pat. No. 4,564,018 (Ultrasonic system for obtaining ocular measurements), each of which is expressly incorporated herein by reference.
Content-Based Query Servers
U.S. Pat. No. 5,987,459 (Swanson, et al. Nov. 16, 1999), expressly incorporated herein by reference, relates to an image and document management system for content-based retrieval support directly into the compressed files. The system minimizes a weighted sum of the expected size of the compressed files and the expected query response time. Object searching of documents stored by the system is possible on a scalable resolution basis. The system includes a novel object representation based on embedded prototypes that provides for high-quality browsing of retrieval images at low bit rates.
U.S. Pat. No. 6,038,560 (Wical, Mar. 14, 2000), expressly incorporated herein by reference, relates to a concept knowledge base search and retrieval system, which includes factual knowledge base queries and concept knowledge base queries, is disclosed. A knowledge base stores associations among terminology/categories that have a lexical, semantic or usage association. Document theme vectors identify the content of documents through themes as well as through classification of the documents in categories that reflects what the documents are primarily about. The factual knowledge base queries identify, in response to an input query, documents relevant to the input query through expansion of the query terms as well as through expansion of themes. The concept knowledge base query does not identify specific documents in response to a query, but specifies terminology that identifies the potential existence of documents in a particular area.
U.S. Pat. No. 6,067,466 (Selker, et al., May 23, 2000), expressly incorporated herein by reference, relates to a diagnostic tool using a predictive instrument. A method is provided for evaluating a medical condition of a patient including the steps of monitoring one or more clinical features of a patient; based on the monitored features, computing a primary probability of a medical outcome or diagnosis; computing a plurality of conditional probabilities for a selected diagnostic test, the computed conditional probabilities including a first probability of the medical outcome or diagnosis assuming the selected diagnostic test produces a first outcome and a second probability of the medical outcome or diagnosis assuming the selected diagnostic test produces a second outcome; and displaying the computed primary probability as well as the plurality of computed conditional probabilities to a user as an aid to determining whether to administer the selected diagnostic test to the patient.
E-Commerce Systems
U.S. Pat. No. 5,946,669 (Polk, Aug. 31, 1999), expressly incorporated herein by reference, relates to a method and apparatus for payment processing using debit-based electronic funds transfer and disbursement processing using addendum-based electronic data interchange. This disclosure describes a payment and disbursement system, wherein an initiator authorizes a payment and disbursement to a collector and the collector processes the payment and disbursement through an accumulator agency. The accumulator agency processes the payment as a debit-based transaction and processes the disbursement as an addendum-based transaction. The processing of a debit-based transaction generally occurs by electronic funds transfer (EFT) or by financial electronic data interchange (FEDI). The processing of an addendum-based transaction generally occurs by electronic data interchange (EDI).
U.S. Pat. No. 6,005,939 (Fortenberry, et al., Dec. 21, 1999), expressly incorporated herein by reference, relates to a method and apparatus for storing an Internet user's identity and access rights to World Wide Web resources. A method and apparatus for obtaining user information to conduct secure transactions on the Internet without having to re-enter the information multiple times is described. The method and apparatus can also provide a technique by which secured access to the data can be achieved over the Internet. A passport containing user-defined information at various security levels is stored in a secure server apparatus, or passport agent, connected to computer network. A user process instructs the passport agent to release all or portions of the passport to a recipient node and forwards a key to the recipient node to unlock the passport information.
U.S. Pat. No. 6,016,484 (Williams, et al., Jan. 18, 2000), expressly incorporated herein by reference, relates to a system, method and apparatus for network electronic payment instrument and certification of payment and credit collection utilizing a payment. An electronic monetary system provides for transactions utilizing an electronic-monetary system that emulates a wallet or a purse that is customarily used for keeping money, credit cards and other forms of payment organized. Access to the instruments in the wallet or purse is restricted by a password to avoid unauthorized payments. A certificate form must be completed in order to obtain an instrument. The certificate form obtains the information necessary for creating a certificate granting authority to utilize an instrument, a payment holder and a complete electronic wallet. Electronic approval results in the generation of an electronic transaction to complete the order. If a user selects a particular certificate, a particular payment instrument holder will be generated based on the selected certificate. In addition, the issuing agent for the certificate defines a default bitmap for the instrument associated with a particular certificate, and the default bitmap will be displayed when the certificate definition is completed. Finally, the number associated with a particular certificate will be utilized to determine if a particular party can issue a certificate.
U.S. Pat. No. 6,029,150 (Kravitz, Feb. 22, 2000), expressly incorporated herein by reference, relates to a system and method of payment in an electronic payment system wherein a plurality of customers have accounts with an agent. A customer obtains an authenticated quote from a specific merchant, the quote including a specification of goods and a payment amount for those goods. The customer sends to the agent a single communication including a request for payment of the payment amount to the specific merchant and a unique identification of the customer. The agent issues to the customer an authenticated payment advice based only on the single communication and secret shared between the customer and the agent and status information, which the agent knows about the merchant, and/or the customer. The customer forwards a portion of the payment advice to the specific merchant. The specific merchant provides the goods to the customer in response to receiving the portion of the payment advice.
U.S. Pat. No. 6,047,269 (Biffar, Apr. 4, 2000), expressly incorporated herein by reference, relates to a self-contained payment system with creating and facilitating transfer of circulating digital vouchers representing value. A digital voucher has an identifying element and a dynamic log. The identifying element includes information such as the transferable value, a serial number and a digital signature. The dynamic log records the movement of the voucher through the system and accordingly grows over time. This allows the system operator to not only reconcile the vouchers before redeeming them, but also to recreate the history of movement of a voucher should an irregularity like a duplicate voucher be detected. These vouchers are used within a self-contained system including a large number of remote devices that are linked to a central system. The central system can e linked to an external system. The external system, as well as the remote devices, is connected to the central system by any one or a combination of networks. The networks must be able to transport digital information, for example the Internet, cellular networks, telecommunication networks, cable networks or proprietary networks. Vouchers can also be transferred from one remote device to another remote device. These remote devices can communicate through a number of methods with each other. For example, for a non-face-to-face transaction the Internet is a choice, for a face-to-face or close proximity transactions tone signals or light signals are likely methods. In addition, at the time of a transaction a digital receipt can be created which will facilitate a fast replacement of vouchers stored in a lost remote device.
Micropayments
U.S. Pat. No. 5,999,919 (Jarecki, et al., Dec. 7, 1999), expressly incorporated herein by reference, relates to an efficient micropayment system. Existing software proposals for electronic payments can be divided into “on-line” schemes which require participation of a trusted party (the bank) in every transaction and are secure against overspending, and “off-line” schemes which do not require a third party and guarantee only that overspending is detected when vendors submit their transaction records to the bank (usually at the end of the day). A new “hybrid” scheme is proposed which combines the advantages of both “on-line” and “off-line” electronic payment schemes. It allows for control of overspending at a cost of only a modest increase in communication compared to the off-line schemes. The protocol is based on probabilistic polling. During each transaction, with some small probability, the vendor forwards information about this transaction to the bank. This enables the bank to maintain an accurate approximation of a customer's spending. The frequency of polling messages is related to the monetary value of transactions and the amount of overspending the bank is willing to risk. For transactions of high monetary value, the cost of polling approaches that of the on-line schemes, but for micropayments, the cost of polling is a small increase over the traffic incurred by the off-line schemes.
Micropayments are often preferred where the amount of the transaction does not justify the costs of complete financial security. In the micropayment scheme, typically a direct communication between creditor and debtor is not required; rather, the transaction produces a result which eventually results in an economic transfer, but which may remain outstanding subsequent to transfer of the underlying goods or services. The theory underlying this micropayment scheme is that the monetary units are small enough such that risks of failure in transaction closure is relatively insignificant for both parties, but that a user gets few chances to default before credit is withdrawn. On the other hand, the transaction costs of a non-real time transactions of small monetary units are substantially less than those of secure, unlimited or potentially high value, real time verified transactions, allowing and facilitating such types of commerce. Thus, the rights management system may employ applets local to the client system, which communicate with other applets and/or the server and/or a vendor/rights-holder to validate a transaction, at low transactional costs.
The following U.S. Patents, expressly incorporated herein by reference, define aspects of micropayment, digital certificate, and on-line payment systems: U.S. Pat. No. 5,930,777 (Barber, Jul. 27, 1999, Method of charging for pay-per-access information over a network); U.S. Pat. No. 5,857,023 (Jan. 5, 1999, Demers et al., Space efficient method of redeeming electronic payments); U.S. Pat. No. 5,815,657 (Sep. 29, 1998, Williams, System, method and article of manufacture for network electronic authorization utilizing an authorization instrument); U.S. Pat. No. 5,793,868 (Aug. 11, 1998, Micali, Certificate revocation system), U.S. Pat. No. 5,717,757 (Feb. 10, 1998, Micali, Certificate issue lists); U.S. Pat. No. 5,666,416 (Sep. 9, 1997, Micali, Certificate revocation system); U.S. Pat. No. 5,677,955 (Doggett et al., Electronic funds transfer instruments); U.S. Pat. No. 5,839,119 (Nov. 17, 1998, Krsul; et al., Method of electronic payments that prevents double-spending); U.S. Pat. No. 5,915,093 (Berlin et al.); U.S. Pat. No. 5,937,394 (Wong, et al.); U.S. Pat. No. 5,933,498 (Schneck et al.); U.S. Pat. No. 5,903,880 (Biffar); U.S. Pat. No. 5,903,651 (Kocher); U.S. Pat. No. 5,884,277 (Khosla); U.S. Pat. No. 5,960,083 (Sep. 28, 1999, Micali, Certificate revocation system); U.S. Pat. No. 5,963,924 (Oct. 5, 1999, Williams et al., System, method and article of manufacture for the use of payment instrument holders and payment instruments in network electronic commerce); U.S. Pat. No. 5,996,076 (Rowney et al., System, method and article of manufacture for secure digital certification of electronic commerce); U.S. Pat. No. 6,016,484 (Jan. 18, 2000, Williams et al., System, method and article of manufacture for network electronic payment instrument and certification of payment and credit collection utilizing a payment); U.S. Pat. No. 6,018,724 (Arent); U.S. Pat. No. 6,021,202 (Anderson et al., Method and system for processing electronic documents); U.S. Pat. No. 6,035,402 (Vaeth et al.); U.S. Pat. No. 6,049,786 (Smorodinsky); U.S. Pat. No. 6,049,787 (Takahashi, et al.); U.S. Pat. No. 6,058,381 (Nelson, Many-to-many payments system for network content materials); U.S. Pat. No. 6,061,448 (Smith, et al.); U.S. Pat. No. 5,987,132 (Nov. 16, 1999, Rowney, System, method and article of manufacture for conditionally accepting a payment method utilizing an extensible, flexible architecture); U.S. Pat. No. 6,057,872 (Candelore); and U.S. Pat. No. 6,061,665 (May 9, 2000, Bahreman, System, method and article of manufacture for dynamic negotiation of a network payment framework). See also, Rivest and Shamir, “PayWord and MicroMint: Two Simple Micropayment Schemes” (May 7, 1996); Micro PAYMENT transfer Protocol (MPTP) Version 0.1 (22 Nov. 95) et seq., www.w3.org/pub/WWW/TR/WD-mptp; Common Markup for web Micropayment Systems, www.w3.org/TR/WD-Micropayment-Markup (9 Jun. 99); “Distributing Intellectual Property: a Model of Microtransaction Based Upon Metadata and Digital Signatures”, Olivia, Maurizio, olivia.modlang.denison.edu/˜olivia/RFC/09/, all of which are expressly incorporated herein by reference.
See, also: U.S. Pat. No. 4,977,595 (Dec. 11, 1990, Method and apparatus for implementing electronic cash); U.S. Pat. No. 5,224,162 (Jun. 29, 1993, Electronic cash system); U.S. Pat. No. 5,237,159 (Aug. 17, 1993, Electronic check presentment system); U.S. Pat. No. 5,392,353 (February 1995, Morales, TV Answer, Inc. Interactive satellite broadcast network); U.S. Pat. No. 5,511,121 (Apr. 23, 1996, Efficient electronic money); U.S. Pat. No. 5,621,201 (April 1997, Langhans et al., Visa International Automated purchasing control system); U.S. Pat. No. 5,623,547 (Apr. 22, 1997, Value transfer system); U.S. Pat. No. 5,679,940 (October 1997, Templeton et al., TeleCheck International, Inc. Transaction system with on/off line risk assessment); U.S. Pat. No. 5,696,908 (December 1997, Muehlberger et al., Southeast Phonecard, Inc. Telephone debit card dispenser and method); U.S. Pat. No. 5,754,939 (May 1998, Herz et al., System for generation of user profiles for a system for customized electronic identification of desirable objects); U.S. Pat. No. 5,768,385 (Jun. 16, 1998, Untraceable electronic cash); U.S. Pat. No. 5,799,087 (Oct. 25, 1998, Electronic-monetary system); U.S. Pat. No. 5,812,668 (Sep. 22, 1998, System, method and article of manufacture for verifying the operation of a remote transaction clearance system utilizing a multichannel, extensible, flexible architecture); U.S. Pat. No. 5,828,840 (Oct. 27, 1998, Server for starting client application on client if client is network terminal and initiating client application on server if client is non network terminal); U.S. Pat. No. 5,832,089 (Nov. 3, 1998, Off-line compatible electronic cash method and system); U.S. Pat. No. 5,850,446 (Dec. 15, 1998, System, method and article of manufacture for virtual point of sale processing utilizing an extensible, flexible architecture); U.S. Pat. No. 5,889,862 (Mar. 30, 1999, Method and apparatus for implementing traceable electronic cash); U.S. Pat. No. 5,889,863 (Mar. 30, 1999, System, method and article of manufacture for remote virtual point of sale processing utilizing a multichannel, extensible, flexible architecture); U.S. Pat. No. 5,898,154 (Apr. 27, 1999, System and method for updating security information in a time-based electronic monetary system); U.S. Pat. No. 5,901,229 (May 4, 1999, Electronic cash implementing method using a trustee); U.S. Pat. No. 5,920,629 (Jul. 6, 1999, Electronic-monetary system); U.S. Pat. No. 5,926,548 (Jul. 20, 1999, Method and apparatus for implementing hierarchical electronic cash); U.S. Pat. No. 5,943,424 (Aug. 24, 1999, System, method and article of manufacture for processing a plurality of transactions from a single initiation point on a multichannel, extensible, flexible architecture); U.S. Pat. No. 5,949,045 (Sep. 7, 1999, Micro-dynamic simulation of electronic cash transactions); U.S. Pat. No. 5,952,638 (Sep. 14, 1999, Space efficient method of electronic payments); U.S. Pat. No. 5,963,648 (Oct. 5, 1999, Electronic-monetary system); U.S. Pat. No. 5,978,840 (System, method and article of manufacture for a payment gateway system architecture for processing encrypted payment transactions utilizing a multichannel, extensible, flexible architecture); U.S. Pat. No. 5,983,208 (Nov. 9, 1999, System, method and article of manufacture for handling transaction results in a gateway payment architecture utilizing a multichannel, extensible, flexible architecture); U.S. Pat. No. 5,987,140 (Nov. 16, 1999, System, method and article of manufacture for secure network electronic payment and credit collection); U.S. Pat. No. 6,002,767 (Dec. 14, 1999, System, method and article of manufacture for a modular gateway server architecture); U.S. Pat. No. 6,003,765 (Dec. 21, 1999, Electronic cash implementing method with a surveillance institution, and user apparatus and surveillance institution apparatus for implementing the same); U.S. Pat. No. 6,021,399 (Feb. 1, 2000, Space efficient method of verifying electronic payments); U.S. Pat. No. 6,026,379 (Feb. 15, 2000, System, method and article of manufacture for managing transactions in a high availability system); U.S. Pat. No. 6,029,150 (Feb. 22, 2000, Payment and transactions in electronic commerce system); U.S. Pat. No. 6,029,151 (Feb. 22, 2000, Method and system for performing electronic money transactions); U.S. Pat. No. 6,047,067 (Apr. 4, 2000, Electronic-monetary system); U.S. Pat. No. 6,047,887 (Apr. 11, 2000, System and method for connecting money modules); U.S. Pat. No. 6,055,508 (Apr. 25, 2000, Method for secure accounting and auditing on a communications network); U.S. Pat. No. 6,065,675 (May 23, 2000, Processing system and method for a heterogeneous electronic cash environment); U.S. Pat. No. 6,072,870 (Jun. 6, 2000, System, method and article of manufacture for a gateway payment architecture utilizing a multichannel, extensible, flexible architecture), each of which is expressly incorporated herein by reference.
Neural Networks
The resources relating to Neural Networks, listed in the Neural Networks References Appendix, each of which is expressly incorporated herein by reference, provides a sound basis for understanding the field of neural networks (and the subset called artificial neural networks, which distinguish biolofical systems) and how these might be used to solve problems. A review of these references will provide a state of knowledge appropriate for an understanding of aspects of the invention which rely on Neural Networks, and to avoid a prolix discussion of no benefit to those already possessing an appropriate state of knowledge.
Wavelets
The following resources listed in the Wavelets References Appendix relate to Wavelets and wavelet based analysis, each of which is expressly incorporated herein by reference, provides a sound basis for understanding the mathematical basis for wavelet theory and analysis using wavelet transforms and decomposition, and how these might be used to solve problems or extract useful information from a signal. A review of these references will assure a background in this field for an understanding of aspects of the invention which rely on wavelet theory.
Telematics
The resources relating to telematics listed in the Telematics Appendix, each of which is expressly incorporated herein by reference, provides a background in the theory and practice of telematics, as well as some of the underlying technologies. A review of these references is therefore useful in inderstanding practical issues and the context of functions and technologies which may be used in conjunction with the advances set forth herein.
Game Theory
The following resources listed in the Game Theory References Appendix, relating to Game Theory, each of which is expressly incorporated herein by reference, provides a basis for understanding Game Theory and its implications for the design, control, and analysis of systems and networks. A review of these references will assure a background in this field for an understanding of aspects of the invention which relate to game Theory.
Use of Game Theory to Control Ad Hoc Networks
The resources relating to ad hoc networks and game theory listed in the Game Theory and Ad Hoc Networks References Appendix, each of which is expressly incorporated herein by reference, provides a sound basis for understanding the implications of game theory for the design, control and analysis of communications networks, and in particular, ad hoc networks. A review of these references will assure a background in this field for an understanding of aspects of the invention which rely on these topics.
The following patents are expressly incorporated herein by reference: U.S. Pat. Nos. 6,640,145, 6,418,424, 6,400,996, 6,081,750, 5,920,477, 5,903,454, 5,901,246, 5,875,108, 5,867,386, 5,774,357, 6,429,812, and 6,252,544. | {
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This invention relates to a method of brazing aluminium or aluminium alloy parts, and more particularly the method of brazing them with a flux.
The invention also relates to an atmosphere furnace which can advantageously be employed for such brazing method.
When iron, copper, or their alloys are put into a furnace employing as its atmosphere a reductive gas such as hydrogen and carbon monoxide, and are subjected to a high temperature, they are deoxidized. Therefore, the brazing of such metals within such atmosphere furnace does not need a flux.
On the other hand, as aluminium and its alloys are not deoxidized even under an extremely low partial pressure of oxygen, they can not be brazed by heating them within the atmosphere furnace of the kind mentioned above. Accordingly, their brazing has been made not by an atmosphere but by the use of a flux.
Conventional brazing may be summarized that the brazing of iron, copper, or their alloys by heating them within a furnace employs a reductive atmosphere but does not need a flux, while the brazing of aluminium and its alloys does employ a flux but does not need a reductive atmosphere.
On the contrary to the above-summarized conventional brazing methods, it becomes lately useful or essential for brazing, with a flux, aluminium and its alloys to employ an inert atmosphere, too. This is in order to braze aluminium parts with a minimum amount of flux and effectively without causing environmental pollution.
To wit, as those fluxes which are commonly used for brazing aluminium parts and have a melting point of 500-550.degree. C., are made from fluorine compounds such as aluminium fluoride, potassium tetrafluoroaluminate, sodium fluoride, and so on, or alkali metal chloride containing one or more fluorine compounds, they are soluble only slightly in water, and accordingly it needs a large volume of water to wash off them. In order to reduce the volume of water for washing off them or to eliminate a washing step in view of environmental pollution, they must be used as minimum as possible.
While the reduction of use of fluxes can be against environ-mental pollution, especially water pollution, it can be economic too. It can yield fine aluminium articles with little flux residues. It can prevent a furnace from being eroded much by fluxes.
However, fluxes which have been applied over aluminium parts thinly in order to minimize them, are readily oxidized at a high temperature. Oxidized fluxes of the kind mentioned above will have a melting point more than 1,000.degree. C. Since a melting point of Al--Si system solders which are commonly used in aluminium brazing, is about 500-630.degree. C., and since the aluminium or aluminium alloy brazing is conducted at about 580-660.degree. C., the oxidized fluxes having the melting point as high as 1,000.degree. C. are unserviceable. They will induce secondary oxidation of aluminium or aluminium alloy parts, to which they have been applied.
Consequently, even in the brazing of aluminium or aluminium alloy parts, heating them under an inert atmosphere becomes essential, as described above, in order to prevent fluxes from oxidizing. In practice, a hermetic metallic muffle filled up with nitrogen gas of a high purity is installed in a furnace, and the aluminium or aluminium alloy parts are brazed with a flux under an inert atmosphere within the metallic muffle.
While such metallic muffle protects its atmosphere from an outer disturbance, electric heating elements which are installed in a space between the muffle and inner furnace walls, are protected by the muffle from fluxes scattered therein, whereby the muffle prevents the heating elements from troubling electrically on account of the fluxes. Although metallic muffles work so, it is not easy to replace them when they are damaged by fluxes and so on. As metallic muffles employed today are as long as 10 m, it is laborious to install or replace them.
It is therefore an object of this invention to provide a method of continuously brazing aluminium or aluminium alloy parts with the use of fluxes and under an inert atmosphere such as nitrogen within a furnace which does not employ any metallic muffle, and to provide also the furnace which can carry out the method well. | {
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The invention concerns a method for applying films to interior wall sections of the bodywork of a vehicle during the course of assembly line production of the vehicle. In addition, the invention relates to a suitable device for execution of said method.
The use of films is known in the construction of vehicles in order to undertake acoustical measures and also for purposes of reinforcement. The acoustical measures include (body) sound-proofing, sound dissipation, sound isolation, sound absorption and sound reflection, etc. Films applied to larger sheet metal sections not only have sound deadening but also stabilizing or reinforcing effects.
The term “film” has acquired a particular meaning in the specialized trade language, independent of its purpose. It involves layer sections which, depending upon the effect to be achieved, may have the most diverse construction (single layer- or multi-layer systems made of different materials, frequently bitumen). The general term “film” is retained in the following.
Films of this kind are employed in many areas of a vehicle. Among them are interior surface sections of doors (two or four) side walls (for example with two doors) wheel cases, in particular wheel cases adjoining the passenger compartment floor sheet metal pieces (for example two each in front and/or in the rear), also in the trunk sheet metal walls between engine compartment and passenger compartment interior side of the roof (overhead), engine compartment
Application of films on interior wall sections of vehicles may be impeded by other structures. This applies, for example, with respect to doors, which are as a rule constructed in two-sheet fashion. The side wall of a door case facing the passenger compartment is equipped with openings, through which must be passed the films to be applied to the inner surface of the outer side wall. This process is all the more difficult the smaller the openings in the inner side wall of the door casing or the larger the films are, since the films have adhesive effect, either due to adhesive forces (layer of glue applied on the film) or due to magnetic forces (magnetic material arranged in the film, in particular in form of powders). Applications of films of this type are highly time consuming and their placement is not precise.
Deposition or application of films on interior wall sections of vehicles or vehicle components was originally done by hand. In modern assembly lines frequently ten or more persons were busy applying various respectively delivered films to the designated interior wall sections. In this phase, the car body is still in its raw state, i.e. the car body components have been welded and their surface has been primed. So that the films will adhere up to their final fusion with the respective sheet metal section on vertical areas or in the case of overhead installation, they have, as already mentioned, adhesive properties. For that purpose, they can be equipped on one side with an adhesive layer. Another possibility consists in utilizing films comprising ferro-magnetic additions, which will temporarily adhere to the sheet metal sections based on magnetic forces. Following application of films performed in this manner on the pertinent interior wall sections of the raw bodywork, they are given a coat of lacquer.
As a rule, several coats of lacquer are applied. Subsequently, the car body is passed through an oven in which drying of the lacquer takes place. In addition, due to the thermal effect, final fusion of films with their respective wall section takes place. The thus attained full-surface positioning of the films on their respective base is a required pre-requisite so that the desired effect will definitely be achieved.
It is a drawback with respect to the described method of applying the films by hand on their pertinent sheet metal sections, since creation of dust and in particular of lint is unavoidable. These stick to the surface of the car body, which is subsequently given a coat of lacquer. Consequently the lint caught in the coats of lacquer results in uneven lacquer surfaces. They must be re-worked by grinding, by another coat of lacquer and by drying. In addition, the known method is relatively expensive based on high amount of manual labor.
In order to avoid the described drawbacks, utilization of a robot is known from DE-A1-199 27 105, i.e. an apparatus with a multi-member arm and a movably thereto attached gripping framework. With the aid of the gripping framework, one or several films are taken up outside the car body, after that the film or films together with the gripping framework is/are transported to the deposit site with the aid of the arm through an opening in the car body and deposited there.
Due to the fact that the application of the films is no longer done by hand, a significant source for the creation of dust or lint is eliminated. Time-consuming and costly re-work on the lacquer surfaces is done away with. In addition, placement of the films on the pertinent inner wall sections can take place with significantly greater precision, so that primarily the desired acoustical effect can be achieved more reliably. Finally, utilization of apparatuses executing placement of the films is more cost-effective over the long term.
With respect to the currently popular large dimensioned vehicles having a multitude of windows, frequently also several sliding roofs, and in case of trailers as well as residential trailers, there likewise exists the need to apply a multitude of differently large and individually cut or preformed films onto a corresponding multitude of interior wall sections of the respective vehicle. The gripping framework of the prior known robot must therefore be passed in and out of the car body, even if it can accept several films. This results on the one hand in relatively long installation times. And, on the other hand, the technical requirements with respect to the length and articulation of the rotor arms and the alignment possibilities of the gripping framework are high in order to reach from the outside all sites to be covered with film, in particular the places located relatively high on the interior side of the roof and overhead. | {
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1. Field of the Invention
The present invention relates to the field of display, and in particular to a high resolution demultiplexer (demux) driver circuit.
2. The Related Arts
The panel display devices, such as, liquid crystal display (LCD) and organic light-emitting diode (OLED) display, comprise a plurality of pixels arranged in an array. Each pixel usually comprises three sub-pixels of red, green and blue respectively. Each sub-pixel is controlled by a gate line and a data line. The gate line is to control the sub-pixel for conduction state, i.e., ON and OFF. The data line is to apply different data voltages to the sub-pixel so that the sub-pixel displays different grayscale to achieve full color display.
As the recent development of high pixel per inch (PPI) panel, more and more panels of higher resolution consume more power due to heavier load and higher frequency. One of the major power consumption comes from the design of the demultiplexer (demux). For high resolution design, because the charging time for demux becomes short, the demux changes from 1-to-many to 1-to-2. For example, for small-size panel with resolution as high as 4K, the 1-to-2 demux is used. Because the PPI is high enough so that a power-saving mode can be activated to cut the resolution to half for the signal line in the Y-direction to reduce the power consumption.
Refer to FIG. 1. FIG. 1 is a schematic view showing the circuit of a known 1-to-2 demux. Based on the known RGB display panel, the circuit of the display panel is of a regular specification, and row scan lines G1, G2, . . . , are connected respectively to sub-pixels of corresponding rows, and data lines D1, D2, . . . , are connected respectively to sub-pixels of corresponding columns. Each sub-pixel is connected through a corresponding thin film transistor (TFT) corresponding to the row of which the sub-pixel belongs to and the data line corresponding to the row of which the sub-pixel belongs to and the data line corresponding to the column of which the sub-pixel belongs to. The circuit of the demux comprises a plurality of multiplexer (mux) modules. Take the mux module 10 as example. The mux module 10 comprises two TFTs, with the gates connected respectively to a first shunt control signal demux1 and a second shunt control signal demux2, the sources connected to the same data signal Data1 (+), i.e., a voltage of the same polarity from the data integrated circuit (IC) signal, and the drains connected respectively to data line D1 and data line D3.
Refer to FIG. 2 and FIG. 3. FIG. 2 is a schematic view showing the power-saving mode signal and circuit of a known 1-to-2 demux circuit, and FIG. 3 a schematic view showing the driving signal in power-saving mode signal of a known 1-to-2 demux circuit. When the power-saving mode is activated, two pixels are considered as a smallest unit (each pixel comprising three R/G/B sub-pixels in FIG. 2). Therefore, the resolution in Y direction is cut to half, as shown FIG. 2, wherein two dash line boxes become the smallest unit, and the levels for the R/G/B color are L240/L127/L30 respectively. The level indicates the index standard for the pixel luminance intensity. In general, for 8-bit RGB color space, 256 levels are used respectively to represent red, green and blue. That is, each color ranges between [0, 255]. In FIG. 2, the levels for R/G/B are 240, 127 and 30 respectively. At this point, the related signals are shown in FIG. 3, comprising: G1 (gate signal), Data1 (+), Data2 (−), Data3 (+), first shunt control signal Demux1 and second shunt control signal Demux2. Although the adjacent same color (with two pixels as the smallest unit) has the same level, the data signal still requires changes in voltage difference. Hence, a large amount of power consumption still incurs. | {
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This invention relates to novel compounds which are useful for treating a variety of cell proliferative disorders such as cancer.
A wide range of growth factors coordinate cell proliferation and differentiation. Malignant cells arise as a result of a stepwise progression of events that include the unregulated expression of growth factors or components of their signaling pathways. Tyrosine phosphorylation events initiated by receptor, cytoplasmic and nuclear kinases and regulated by phosphatases are central to these processes. Mutation, hyper-activation, translocation and overexpression of protein tyrosine kinases are all associated with tumorigenesis. In addition to increasing proliferative rates and immortalizing cells, overexpression of tyrosine kinases can lead to morphological transformation and cause anchorage independence, contributing to the promotion of migratory ability and possibly the induction of metastases.
Certain compounds with structures based upon mimicry of ATP or phosphotyrosine have been shown to be effective kinase inhibitors. Those based upon phosphotyrosine have been demonstrated to be the more specific tyrosine kinase inhibitors. Because of their ability to inhibit tyrosine phosphorylation, these compounds may alter cell responses to growth factors or other process driven by tyrosine kinase activity, including unregulated growth as the result of tyrosine kinase overexpression, mutation, or translocation. Inhibition of tyrosine kinases occupying a central role in proliferative signaling pathways, or in pathways regulating cell cytoskeletal structure, even temporary or incomplete inhibition, may be sufficient to switch a cancerous cell from a proliferative cycle into programmed cell death, or apoptosis. Death by apoptosis is most often observed upon effective treatment with tyrosine kinase inhibitors.
Selective inhibition of specific tyrosine kinases offers a method of targeting cancerous cell growth with a high degree of specificity and minimal toxicity to normally growing cells and tissues. Thus, specific inhibitors of tyrosine kinases have great potential as clinical anti-cancer treatments. A number of small molecules which act as tyrosine kinase inhibitors have been identified. For example, certain phenyl acrylonitrile compounds have been described as tyrosine kinase inhibitors, effective to inhibit cell proliferation (see for example, U.S. Pat. Nos. 5,891,917, 5,217,999, 5,773,476, 5,935,993, 5,656,655, 5,677,329 and 5,789,427).
Inhibition of tyrosine kinases offers one mechanism by which cell proliferation can be inhibited. One of skill in the art will appreciate that other mechanisms of inhibition may also be involved.
There is a need in the art to identify compounds that inhibit cell proliferation.
A number of novel compounds have now been identified that inhibit abnormal cell proliferation, for example cancer cell growth. The compounds do not inhibit the growth of normal cells.
Accordingly, the present invention includes compounds of Formula I and salts, solvates and hydrates thereof:
wherein
R1 and R2 are each independently selected from the group consisting of H, OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, Oxe2x80x94Si(C1-6alkyl)(C1-6alkyl)(C1-6alkyl), NO2, CF3, OCF3 and halo;
R3 is selected from the group consisting of H, OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, Oxe2x80x94Si(C1-6alkyl)(C1-6alkyl)(C1-6alkyl), NO2, halo and CH2xe2x80x94Sxe2x80x94(CH2)nAr;
R4 is selected from the group consisting of C(X)R5, SO3Ar, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), P(O)(OH)2, P(O)(OC1-6alkyl)2, and C(NH2)xe2x95x90C(CN)2;
X is selected from O,S, NH and Nxe2x80x94C1-6alkyl;
R5 is selected from the group consisting of NH2, OH, NH(CH2)pAr, NH(CH2)pOH, (CH2)pOC1-6alkyl, C1-6alkyl, C1-6alkoxy, NHNH2, NHC(O)NH2, NHC(O)C1-6alkoxy, N-morpholino and N-pyrrolidino;
Ar is an aromatic or heteroaromatic group, unsubstituted or substituted with 1-4 substituents, independently selected from the group consisting of OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, NO2, CF3, OCF3 and halo;
n is 0 to 4; and
p is 1-4.
The present invention further includes compounds of Formula II and salts, solvates and hydrates thereof:
wherein
R1 and R2 are each independently selected from the group consisting of H, OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, Oxe2x80x94Si(C1-6alkyl)(C1-6alkyl)(C1-6alkyl), NO2, CF3, OCF3 and halo;
R3 is selected from the group consisting of H, OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, Oxe2x80x94Si(C1-6alkyl)(C1-6alkyl)(C1-6alkyl), NO2, halo and CH2xe2x80x94Sxe2x80x94(CH2)nAr;
Ar is an aromatic or heteroaromatic group, unsubstituted or substituted with 1-4 substituents, independently selected from the group consisting of OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, NO2, CF3, OCF3 and halo;
R6 is selected from the group consisting of Ar, OH and OC1-6alkyl;
X is selected from O and S;
n is 0-4; and
p is 1-4.
The present invention also provides compounds of Formula III and salts, solvates and hydrates thereof:
wherein
R1 and R2 are each independently selected from the group consisting of H, OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, Oxe2x80x94Si(C1-6alkyl)(C1-6alkyl)(C1-6alkyl), NO2, CF3, OCF3 and halo;
R3 is selected from the group consisting of H, OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, Oxe2x80x94Si(C1-6alkyl)(C1-6alkyl)(C1-6alkyl), NO2, halo and CH2xe2x80x94Sxe2x80x94(CH2)nAr;
Ar is an aromatic or heteroaromatic group, unsubstituted or substituted with 1-4 substituents, independently selected from the group consisting of OH, C1-6alkyl, C1-6alkoxy, NH2, NHxe2x80x94C1-6alkyl, N(C1-6alkyl)(C1-6alkyl), SH, Sxe2x80x94C1-6alkyl, NO2, CF3, OCF3 and halo;
R7 is selected from the group consisting of OH, NH2 and OC1-6alkyl;
X is selected from O and S; and
n is 0-4.
According to another aspect of the present invention, there is provided a pharmaceutical composition comprising a compound of the invention and a pharmaceutically acceptable carrier or diluent.
In accordance with a further aspect of the present invention, there is provided a method for modulating cell proliferation, preferably inhibiting cell proliferation comprising administering an effective amount of a compound of the invention to a cell or animal in need thereof. The invention also includes a use of a compound of the invention to modulate cell proliferation, preferably inhibit cell proliferation. The invention further includes a use of a compound of the invention to prepare a medicament to modulate cell proliferation, preferably inhibit cell proliferation.
In a preferred embodiment the present invention provides a method of inhibiting the proliferation of a cancer cell comprising administering an effective amount of a compound of the invention to a cell or animal in need thereof. The cancer cell treated may be any type of cancer including a leukemia, a lymphoma, myeloma, metastatic carcinoma, sarcoma or any other malignant transformation or any other malignancy. The invention also includes a use of a compound of the invention to modulate cancer cell proliferation, preferably inhibit cancer cell proliferation. The invention further includes a use of a compound of the invention to prepare a medicament to modulate cancer cell proliferation, preferably inhibit cancer cell proliferation.
In another aspect, the invention provides a method of modulating tyrosine kinase activity in a cell by administering an effective amount of a compound of the invention. In a further aspect, the invention provides a method of inhibiting tyrosine kinase activity in a cell by administering an effective amount of a compound of the invention. The present invention also provides a use of a compound of the invention to modulate, preferably inhibit, tyrosine kinase activity. The present invention further provides a use of a compound of the invention to prepare a medicament to modulate tyrosine kinase activity, preferably inhibit tyrosine kinase activity. It is appreciated that the inhibition of cell growth by the compounds of the invention may be effected by other mechanisms.
Other features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples while indicating preferred embodiments of the invention are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. | {
"pile_set_name": "USPTO Backgrounds"
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The device of the present invention is an improvement over drilling mud degassers of the type wherein drilling mud is sprayed into a vacuum chamber to remove a substantial amount of the oxygen present in the drilling mud, such as a drilling mud degasser as shown and descrubed in Burgess U.S. Pat. No. 4,084,946.
When a device of the type disclosed in Burgess U.S. Pat. No. 4,084,946 is used for the deoxygenation of water to be used for a secondary recovery operation, the results are not entirely satisfactory in that single stage centrifugation and spray impacting of the water under vacuum will not remove substantially all of the oxygen normally present in water (typically about 10 to 12 parts per million) such that as much as 3 to 5 parts per million or more of oxygen will remain in the treated water. It is normally considered necessary to provide injection water containing less than about 1 part per million of water, and preferably about 0.01 parts per million of oxygen or less. | {
"pile_set_name": "USPTO Backgrounds"
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This disclosure relates to a lubrication system for gas turbine engines and more particularly to a configuration for overcoming oil coking in the lubrication system.
A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. Air entering the compressor section is compressed and delivered into the combustor section where it is mixed with fuel and ignited to generate a high-speed exhaust gas flow. The high-speed exhaust gas flow expands through the turbine section to drive the compressor and the fan section. The compressor section typically includes low and high pressure compressors, and the turbine section includes low and high pressure turbines. High and low spools or shafts respectively support the high pressure and low pressure turbines and compressors.
The engine has bearings that support the high and low shafts. The bearings are typically housed in bearing compartments that are connected to a lubrication system. The lubrication system provides lubricant, such as oil, to the bearing compartment through a supply line to lubricate and cool the bearings. The lubrication system also recovers the oil from the bearing compartment through a scavenge line and sends the oil through a filter and heat exchanger before cycling the oil back to the bearing compartment.
At shutdown of the gas turbine engine, the lubrication system ceases to circulate oil to the bearing compartment and the oil, now without pumping pressure, drains out of both the supply line and the scavenge line and back to a sump or low point in the lubrication system. With the lubrication system inactive and no longer dissipating heat from the bearing compartment, heat produced by the gas turbine engine just prior to shutdown can “soak” into both the bearing compartment and the supply and scavenge lines and can excessively elevate the temperature of these engine components. The elevated temperatures caused by the heat soak back can cause oil mist or film located in the supply and scavenge lines to react with air and form coke deposits on the inside surfaces of the supply and scavenge lines. Over time, these coke deposits can accumulate and clog the tubes preventing oil from flowing to the bearing compartment. Without an adequate supply of oil, the bearings in the bearing compartment can fail and result in engine-wide failure of the gas turbine engine. | {
"pile_set_name": "USPTO Backgrounds"
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Condensing by a condensing optical system a laser light output from a laser light source and irradiating the laser light to a processing object allows processing the processing object. If by simply condensing laser light by use of a lens, scanning laser light to one condensing position allows processing a processing object into a desired shape. However, the time required for processing is long in this case.
The simplest method for shortening the processing time is to perform multi-point simultaneous processing by simultaneously condensing and irradiating laser light to a plurality of condensing positions. For example, using a plurality of laser light sources and condensing laser lights output from the respective laser light sources by a lens allows performing multi-point simultaneous processing. However, in this case, a plurality of laser light sources are used, which thus results in a high cost and a complicated installation area and optical system.
An invention that intends to solve such problems has been disclosed in Patent Literature 1. In this invention disclosed in Patent Literature 1, a hologram is presented on a phase modulating spatial light modulator, a laser light output from one laser light source is phase-modulated by the spatial light modulator, and the phase-modulated laser light is simultaneously condensed and irradiated to a plurality of positions by a condensing optical system. The hologram presented on the spatial light modulator has such a phase modulation distribution that laser light is condensed to a plurality of condensing positions by a condensing optical system. | {
"pile_set_name": "USPTO Backgrounds"
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The invention relates to an optoelectronic device comprising a semiconductor diode laser amplifier, often referred to as amplifier for short hereinafter, with a strip-shaped active region which is bounded in longitudinal direction by two end faces where radiation can enter or leave the amplifier, while at one side of the amplifier are present in that order: a lens, a polarization-changing element, and a mirror, such that radiation passing through said element, reflected by the mirror, and passing through the element once more has a polarization which has been rotated through 90.degree.. In general, an amplifier will have a gain factor which is greater than or equal to one. It is noted, however, that a gain factor smaller than or equal to one is also possible, indeed useful under certain circumstances, during operation. It is also possible for the gain factor to be varied in time, such as is the case, for example, when the amplifier is used as a modulator.
Such a device is used, for example, in an optical glass fiber communication system. The device is particularly suitable for use in the wavelength bands around 1.3 .mu.m and 1.5 .mu.m.
Such a device is known from the article "Polarization-independent configuration optical amplifier" by N. A. Olsson, published in Electronics Letters, 18th August 1988, vol. 24, No. 17, pp. 1075-1076. The device shown therein (see FIG. 1) comprises a semiconductor diode laser amplifier with two end faces where radiation can enter or leave the amplifier. The radiation to be amplified enters the amplifier at one side thereof, and the radiation leaves the amplifier at the other side after being amplified a first time, subsequently passes through a collimating lens and a Faraday rotator which rotates the polarization through 45.degree.. The radiation is subsequently reflected by a mirror, whereupon it follows the above path in reverse order, during which the polarization is once more rotated through 45.degree. upon passing the Faraday rotator. The radiation finally leaves the amplifier, after a second amplification, at the same side where the radiation to be amplified entered the, amplifier. The radiation to be amplified accordingly passes twice through the amplifier, while the polarization of the radiation passing through the amplifier for the second time has been rotated through 90.degree. compared with the polarization of the first passage. A polarization sensitivity, which is always present in the amplifier and which means that the gain is dependent on the polarization, is neutralized thereby. This means that the final gain achieved no longer depends on the polarization of the radiation to be amplified. In other words, the amplifier is polarization-insensitive in the given configuration. This is of major importance in a number of applications, such as wavelength multiplexing, or more in general applications where it is not possible to keep the gain constant by means of an (opto)electronic feedback control mechanism because of the necessary very high switching speeds.
A disadvantage of the known device is that it has a comparatively low efficiency in practice. This means that the amplifier must be operated at a comparatively high gain factor, which involves several further disadvantages. It is also found that the efficiency varies from one device to another. | {
"pile_set_name": "USPTO Backgrounds"
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Nowadays, people pay much attention to the air quality in the environment. For example, it is important to monitor carbon monoxide, carbon dioxide, volatile organic compounds (VOC), Particulate Matter 2.5 (PM2.5), nitric oxide, sulfur monoxide, and so on. The exposure of these substances in the environment will cause human health problems or even harm the life. Therefore, it is important for every country to monitor the air quality in the environment, which is a topic currently being valued.
Generally, it is feasible to use a gas sensor to monitor the air quality in the environment. If the gas sensor is capable of immediately providing people with the monitored information relating to the environment for caution, it may help people escape or prevent from the injuries and influence on human health caused by the exposure of the substances described above in the environment. In other words, the gas sensor is suitably used for monitoring the ambient air in the environment.
Currently, to achieve reaction detection, the gas is transported to the reaction material of a surface of the gas sensor, and thus gas monitoring is performed. Moreover, as shown in FIG. 1, the gas sensor 2 is usually disposed in a separated detecting chamber 1 for performing gas detection, and thus the detected gas would not be interfered by external factors. The detecting chamber 1 has an inlet 1a and an outlet 1b. The external gas enters the detecting chamber 1 through the inlet 1a by natural convection and flows slowly, after which the gas is spread to the surface of the gas sensor 2 for performing the reaction detecting, and discharged through the outlet 1b, so that the gas detection is achieved. Since the gas to be monitored by the gas sensor 2 is guided into the detecting chamber 1 by natural convection, it takes too long to transport the gas so that the sensing efficiency of the gas sensor 2 is negatively affected, and the immediate detection cannot be achieved.
In order to solve the above-mentioned problem and achieve the immediate detection, a fan (not shown) is assembled in the detecting chamber 1. Generally, a conventional fan is rotary motor-driven type. Although the fan speeds up the gas transportation to the detecting chamber 1, the sensitivity of sensing by the gas sensor 2 may be affected and distorted as the flow rate of the gas increases or chaos airflow occurs. This is because the gas molecule cannot be caught by the gas sensor 2 immediately for being dissolved in or bonded to the reaction material on the surface of the gas sensor 2. In addition, it takes time for the reaction material to react with the caught gas molecule. Therefore, a stable airflow of the gas flowing over the surface of the gas sensor 2 is required. The way of increasing the flow rate of gas by the fan is not suitable because it would cause high flow rate or chaos airflow. Moreover, as the fan is utilized to increase the flow rate of gas, a period of acceleration time is required for driving the fan while the fan is activated, so that the fan is driven to rotate at a specific rotational speed and generate high flow rate of gas. In addition, a period of deceleration time is required for stopping the fan from rotating. Therefore, when the fan is activated or deactivated, a period of acceleration time or deceleration time is required as the fan is driven in an inertial way. Since activating and deactivating the fan both take a period of time, adopting the fan to increase the flow rate of gas is not suitable for immediate detection. Consequently, there is a need of making the gas transportation appropriate for achieving the immediate detection.
There is a need to improve the gas sensor in monitoring the gas with accurate sensitivity and immediate response. In addition, there is a need of miniaturizing the gas sensor and the detecting chamber for possessing portability and monitoring everywhere and any time. If the fan is utilized to increase the flow rate of gas, the volume of the fan is hard to be miniaturized. Consequently, the present disclosure provides a portable gas detecting device capable of monitoring and sampling immediately. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field
The inventive concept relates to a communication module assembly.
2. Description of the Related Art
As a penetration rate of a mobile communication terminal is increased due to the development of communication technology and desire for user's needs and communication quality are increased, a mobile communication repeater is spreading to meet the demands. The mobile communication repeater is a device that connects a base station and a terminal.
In addition, even though the base station can receive radio frequency signals from an exchanger of a mobile communication provider to enable communication services, the mobile communication repeater is used to transmit radio frequency signals of the base station more accurately and further because of the limited range of radio frequency signals from the base station. Usually, a large number of mobile telecommunication repeaters are installed in small cities or mountainous areas that are far away from base stations rather than big cities.
Various types of mobile communication repeaters have been disclosed for various purposes. Typical mobile communication repeaters include an optical repeater and a radio frequency (RF) repeater. The optical repeater has a method of receiving radio frequency signals of a base station located closest to an area where the optical repeater is installed and transmitting the radio frequency signals to an area where radio frequency signals are unstable or communication quality is weak through an optical cable. The RF repeater is a wireless communication device for solving a shaded area of underground or ground where it is difficult to transmit signals, and is used for smooth communication by providing signal amplification and a radio path between a base station and a terminal.
The mobile communication repeater has a case and various internal components for communication repeat in the case. Depending on the situation, required internal components of the mobile communication repeater may be different. In a conventional mobile communication repeater, if one of the internal components is disconnected, electrical connection to other internal components is cut off and a separate cable needs to be connected. In particular, considering that the mobile communication repeater is mounted and used in a place where user's accessibility is difficult, such as an upper end of a telephone pole, it is difficult to separate internal components. Therefore, countermeasures are required. | {
"pile_set_name": "USPTO Backgrounds"
} |
This application claims the priority of the European patent application No. 99 810 381.6, filed on May 4, 1999, the disclosure of which is incorporated herein by reference in its entirety.
The invention refers to the field of magnetic force or Hall probe microscopy. It is based on a method for calibrating a magnetic force microscope (MFM) or a scanning Hall probe microscope (SHPM), wherein a raw MFM- oder SHPM-image S is measured by scanning a sample with a microscopic tip and an instrument response function IRF is determined for calibrating the MFM or SHPM.
The invention relates to a state of the art as presented in the article of J.-G. Zhu et al., xe2x80x9cMagnetic force microscopy image restoration technique for removing tip dependencexe2x80x9d, Journal of Applied Physics Vol. 83 (11), p. 6223-6225 (1998). It is proposed to use samples that approximate a point source of magnetic field, i. e. a magnetic monopole or dipole, in order to determine an impulse response function of the magnetic force microscope (MFM) tip. The impulse response function is then used to deconvolve raw MFM-images in the Fourier space. This method has severe drawbacks. The better the sample approximates a point source the smaller the MFM-signal will be. This severely limits the accuracy of the calibration, due to the small signal-to-noise ratio of the measurement. Moreover, point source samples are difficult to produce. Their spatial extent limits the accuracy to which the impulse response function can be determined. For repeated calibrations repeated positioning of the point source sample is necessary.
Principles of operation of MFMs are shown in the article of D. Rugar et al., xe2x80x9cMagnetic force microscopy: General principles and applications to longitudinal recording mediaxe2x80x9d, Journal of Applied Physics, Vol. 68 (3), P. 1169-1183 (1990). The MFM response is analyzed in direct space by modelling the tip geometry and cantilever tilt. However, the geometric tip model is complicated and of limited value since four fitting parameters are used.
Another tip calibration technique is presented in the article of L. Kong et al., xe2x80x9cQuantification of magnetic force microscopy using a micronscale current ringxe2x80x9d, Applied Physics Letters Vol. 70 (15), p. 2043-2045 (1997). A controlled magnetic field of a ring conductor with 1 xcexcm-5 xcexcm diameter is probed by the tip. The resulting MFM-signal is interpreted in terms of a magnetic monopole and dipole strength of the tip. Again a tip model is required to quantify magnetic properties of the tip.
Principles of operation of Scanning Hall probe microsopes (SHPM) are shown in the article of A. Oral et al., xe2x80x9cReal-time scanning Hall probe microscopyxe2x80x9d, Applied Physics Letters Vol. 69 (9), p. 1324-1326 (1996). A tip comprising a submicron Hall probe manufactured in a GaAs heterostructure is scanned over the sample to measure the magnetic stray field using conventional scanning tunneling microscopy positioning techniques. However, the magnetic field sensitivity decreases on the length scale of the Hall probe tip and requires calibration for absolute stray field measurements.
Hence, it is a general object of the invention to provide a simplified and improved calibration method for magnetic force microscopes (MFM) and scanning Hall probe microscopes (SHPM). Now, in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the calibration method comprises the steps of providing a sample with an irregular sample magnetization pattern M or an irregular current distribution over an extended area, determining, based on the raw MFM- or SHPM-image S of the sample, an approximate sample magnetization pattern M0 and therefrom an approximate sample magnetic stray field distribution H0, and calculating the instrument response function IRF from the raw MFM- or SHPM-image S and the approximate sample magnetic stray field distribution H0.
Thus one aspect of the invention resides in a method for calibrating a magnetic force microscope or a scanning Hall probe microscope, wherein raw MFM- or SHPM-images of a sample producing an arbitrary magnetic stray field are measured, the sample magnetization or current distribution patterns are estimated, the corresponding magnetic stray fields are calculated and, from the raw MFM- or SHPM-images and the magnetic stray fields, an instrument response function IRF is determined. The instrument response function IRF contains information on the magnetic stray field distribution of the tip and the tilt and mechanical behaviour of the cantilever.
By using a calibrated tip the magnitude and distribution of magnetic stray fields of arbitrary samples can be determined. Through this, also the magnetization or current distribution in the samples can be found.
The method according to invention allows to measure rather than to model the instrument response. The magnetic stray field distribution or sensitivity of the tip is determined with high precision and without restriction to magnetic monopole or dipole models. The need for preparing samples with a specific pattern of magnetic field sources is eliminated.
In another aspect of the invention the calibration method comprises the steps of determining, based on the raw MFM- or SHPM-image S, an approximate sample magnetization pattern M0 and therefrom an approximate sample magnetic stray field distribution H0, calculating Fourier space distributions of the raw MFM- or SHPM-image S(k) and of the approximate sample magnetic stray field distribution H0(k), and calculating an instrument response function IRF(k)=S(k)/H0(k). The instrument response function IRF is thus calculated by deconvolution in Fourier space of the raw MFM- or SHPM-image with the magnetic stray field.
In a further aspect of the invention the calibration method comprises the steps of: a) measuring a plurality of raw MFM or SHPM-images Si (i=1 . . . n), b) determining first approximate sample magnetization patterns Mi,0 and first approximate sample magnetic stray field distributions Hi,0, and c) calculating from Si, and Hi,0 first approximate instrument response functions IRFi,0 and averaging them to form an initial instrument response function IRF0. Thus a plurality of MFM- or SHPM-images is measured and the average of their instrument response functions delivers an improved instrument response function IRF0.
In one embodiment the preceding steps b) and c) are reiterated by using a (jxe2x88x921)-th instrument response function IRFjxe2x88x921 to recalculate magnetization patterns Mi,j, magnetic stray field distributions Hi,j and a j-th instrument response function IRFj (j=1 . . . m). In other words, based on the averaged instrument response function IRF0, an iterative calculation of approximate sample magnetization patterns, approximate sample magnetic stray field distributions and improved averaged instrument response functions IRFj (j=1 . . . m) is performed. With an increasing number of iterations j the instrument response functions IRFj converge towards a xe2x80x9ctruexe2x80x9d instrument response function.
Other embodiments refer to choosing samples with magnetization vectors oriented perpendicular to a sample surface to be scanned, to replacing the sample magnetic stray field distribution H by its derivative H,z in case of dynamic measurements, and to applying the calibration method to measure absolute values of magnetic stray fields H, magnetization patterns M or microscopic current distributions.
In further embodiments a tip calibration function qtip, characterizing the magnetic stray field distribution of the tip of a magnetic force microscope, is derived from the instrument response function IRF. The tip calibration function qtip is useful to characterize the response of integrated circuits, magnetic reading heads, Hall sensors or SQUIDS to local magnetic fields or even to generate absolute microscopic magnetic gauging fields. | {
"pile_set_name": "USPTO Backgrounds"
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Computers are having a growing impact in many areas of society. The lowering costs, increasing performance capability and increasing access to networks, for example, the Internet, is allowing computers to be used more easily and effectively. Further, many of today's computers enable applications and capabilities to be added to (i.e., loaded onto) computers by end users.
Although access to networks and the ability to add applications and capabilities to a computer has many well-known benefits, such access and ability sometimes can be detrimental.
For example, many households include personal computers to which children have access. Although the Internet and other networks make available a wealth of content (i.e., information), many parents do not wish all of this content (e.g., adult content) to be available to their children. However, there is often nothing to prevent a child from accessing adult content on the Internet or another network.
Further, a growing problem in the workplace is that employees are wasting time exploring the Internet (i.e., “surfing the net”). A similar problem exists in classrooms that provide Internet access, where students refrain from taking notes or paying attention to a lecture so that they may explore the Internet. In addition, students frequently are found in the classroom—or workers in the workplace—playing games or playing videos or music that came pro-loaded on their computers or that they loaded on to their computers. Yet another situation in which it is not desirable for students to have access to at least some content on an accessible network and/or and on their own computers is when a computer is being used by the student to take an exam.
As used herein, an “examination” or “exam” is a process that includes a set of one or more questions being asked, either orally or in writing, and may include receiving, either orally or in writing, a response to one or more of the questions.
As used herein, “taking an examination” or “taking an exam” includes being posed a set of one or more questions either orally or in writing, as part of an exam, and may include providing a response, either orally or in writing, to one or more of the questions.
The role of computers in education is growing. An increasing number of students, to starting at increasingly younger ages, are exposed to computers and use them in preparing school work. This preparation may include, among other activities, on-line research over the Internet, preparation of projects, preparation of written reports and use of learning exercises.
In many colleges (or universities), for entering freshmen and other classes of students, having access to a computer, particularly a laptop, is either a requirement or practically a necessity. To satisfy this growing need, colleges often have programs by which students can purchase or lease laptop computers at favorable rates. Many college campuses are updating their networking infrastructures to provide students with continuous and uninterrupted access to the college's local network and to the Internet.
Many professors are integrating their students' use of computers with the professors' classroom materials. For example, materials presented by a professor as part of teaching a course may be available on-line, for example, on the college's local network, and students typically can communicate with the professor via e-mail. This integration is occurring across a variety of disciplines, but is not confined merely to the science and engineering disciplines.
Computers and the software tools that run on them are affecting the way students prepare their work. A student typically takes advantage of the word-processing capabilities provided by computers and software tools to prepare written class work (i.e. a writing), for example, a paper, an essay, a thesis, written answers to part of a homework assignment, or a written part of a class project. The flexibility provided by many of today's word processing programs enables a student to fine-tune a writing by adding, rearranging and refining the writing's content (e.g., deleting, copying, cutting and pasting) until the writing is completed. A student may use this flexibility to prepare a writing by initially compiling a rough draft, knowing that rearrangement and refinement can readily be accomplished using the word processing program. Thus, typically, a writing submitted to the professor (or often an assistant of the professor) is not merely the student's first (and only) draft, but a product of the student reviewing and revising the first draft to produce the completed writing.
Notwithstanding the fact that computers appear firmly entrenched in a student's preparation of course work, there remains at least one area of school education where computers are not welcome. Even with their pervasive use, computers typically are barred from the examination (exam) room. A student may take notes in class on his laptop computer, communicate with the professor via e-mail, prepare writings using the computer, submit these writings via e-mail, and even receive a grade on the writing via-email from the professor, however, for exams (e.g., a midterm or a final exam), students often are confronted with a sign that reads something like: PLEASE CHECK YOUR LAPTOP COMPUTER AT THE DOOR. Thus, students typically are not allowed to use their laptops or any other computer to take an exam.
As a result, a student that may be conditioned and comfortable with expressing her thoughts in a rough draft using a computer, knowing that she can rearrange and refine the rough draft later, no longer has this ability at exam time. Under pressure and in handwriting, the student must prepare a coherent, well-organized and legible response to an exam question, frequently in an infamous “blue book.”
The grader (professor or assistant) of the exams also suffers from the banning of laptops from the exam room. From the grader's perspective, after being able to read writings submitted electronically (e.g., via e-mail) throughout the semester, where each writing reflects a respective student's capabilities in the subject matter of the course, the grader must now plow through a stack of handwritten exam answers, many of which may be barely legible or completely illegible. As many graders acknowledge, the penmanship of students is deteriorating, most likely due to the more frequent use of a keyboard as opposed to handwriting to prepare writings, including communicating with other people (e.g., email), taking notes in class and preparing writings for classes. This poor penmanship compounds the difficulty of grading handwritten answers to exam questions.
Restricting laptop computers from exam rooms stems from the fear that during the exam students will have access to unauthorized content on the computer (or by using the computer to access unauthorized content on a network), and that this content will assist the student in taking the exam. In other words, there is a fear that students will cheat during the exam by accessing unauthorized content to assist them in providing answers to the exam questions. Content is unauthorized if the individual giving the exam (e.g., a professor) does not authorize the content for use by the student during the exam. In many circumstances, the risk and ease of cheating is so great that school administrators do not allow student laptops or other computers into the exam room for fear that cheating will become rampant.
Today, it appears that the use of computers in the classroom will continue to grow. Thus, restricting computers from the exam room should be addressed. Not being able to use a computer in the exam room may be deemed unfair or undesirable by both the students and the graders. For the reasons described above, by restricting a student from using a computer to take an exam, thereby forcing a student to handwrite answers, a student's knowledge and understanding of the material taught during the semester may not be determined accurately.
Accordingly, to allow students to use their computers during an exam and to prevent cheating by students, there is needed a technique for securing a variety of types of computers, for example, a laptop, or a personal computer or a workstation found in a computer lab so that unauthorized content may not be accessed during the exam.
More specifically, needed is a technique for securely executing an application, such as an application for receiving answers from a user to exam questions, on computers such that unauthorized content cannot be accessed during execution of the exam, so that a student's computer may be transformed into a secure exam-taking environment. Being able to transform any of a variety of types of computers into a secure exam-taking environment may be desirable to eliminate the need for dedicated exam-taking computers. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The application relates to an exhaust system of a snowmobile that has an exhaust pipe extending above a track belt from an engine compartment to a rearward portion of a vehicle frame.
2. Description of the Related Art
Conventional snowmobiles provide a seat for a rider on an upper part of the vehicle body from which the rider can grip a front steering handle. In such snowmobiles, an engine typically is mounted in an engine compartment located in a forward portion of the vehicle body. Exhaust gas generally is discharged below the engine compartment. However, in this arrangement, most of the heaviest components of the snowmobile, e.g., the engine and the exhaust pipe, are positioned at the forward portion of the vehicle body. As such, the weight of the forward portion of the vehicle body is large compared to the weight of the rearward portion.
In one prior design, a snowmobile is arranged such that the weight balance is improved by positioning a muffler and a substantial portion of the exhaust pipe at a rearward portion of the vehicle body. In this prior design, the engine is mounted in the engine compartment in the forward portion of the vehicle body. Other components that form an external portion of the vehicle, e.g., the external surface of the snowmobile, such as the fuel tank and the seat, are positioned at a rearward portion, above the track belt. Also, the exhaust pipe of this prior design extends in a longitudinal direction of the vehicle body between the track belt and an upper frame portion to which external components such as the fuel tank and seat are attached. A muffler is positioned downstream beside the rear end of the vehicle body. The muffler is accommodated in a rear end of the seat. In this prior design, a tail pipe is provided for discharging exhaust gas to the atmosphere. The tail pipe is provided on both lateral sides of the muffler and of the vehicle, extending rearward and upward. Additionally, the tail pipe protrudes rearward from the rear end part of the seat. As such, this conventional exhaust system discharges the snowmobile's exhaust gas rearward and upward from the rear end of the vehicle body. | {
"pile_set_name": "USPTO Backgrounds"
} |
Computing devices and communication networks can be utilized to exchange information. In a common application, a computing device can request content from another computing device via a communication network. For example, a user at a personal computing device can utilize a software browser application, typically referred to as a browser, to request a web page from a server computing device via the internet. In such embodiments, the user computing device can be referred to as a client computing device and the server computing device can be referred to as a content provider.
The communication networks utilized to exchange information can vary widely in availability, coverage area, bandwidth, and the like. Some networks, such as cellular networks like 3G, are available nationwide. Other networks, such as WLANs and other WiFi-based networks, have much smaller coverage areas and may be incompatible with WiFi-based networks elsewhere. The bandwidth on such WiFi networks, however, can be many times greater than the bandwidth available through cellular networks.
Users can connect to such communication networks to request and interact with network content, such as web sites and pages. One or more requests for web pages or other network content may form the basis for predicting which web pages and network content will be requested in the future. The predictions can be used to cache the predicted content before it is requested to minimize latency and other network delays when the content is requested.
From the perspective of a user operating a client computing device, a user experience can be defined in terms of the performance and latencies associated with obtaining network content over a communication network. Latencies and performance limitations of any of the above processes may diminish the user experience. Additionally, latencies and inefficiencies may be especially apparent on computing devices with limited resources, such as processing power, memory or network connectivity such as netbooks, tablets, smartphones, and the like. | {
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Environmental interests and an increasing demand for diesel fuel, especially in Europe, encourage fuel producers to employ more intensively available renewable sources. In the manufacture of diesel fuels based on biological raw materials, the main interest has concentrated on vegetable oils and animal fats comprising triglycerides of fatty acids. Long, straight and mostly saturated hydrocarbon chains of fatty acids correspond chemically to the hydrocarbons present in diesel fuels. However, neat vegetable oils display inferior properties, particularly extreme viscosity and poor stability and therefore their use in transportation fuels is limited.
Conventional approaches for converting vegetable oils or other fatty acid derivatives into liquid fuels comprise transesterification, catalytic hydrotreatment, hydrocracking, catalytic cracking without hydrogen and thermal cracking among others. Typically triglycerides, forming the main component in vegetable oils, are converted into the corresponding esters by the transesterification reaction with an alcohol in the presence of catalysts. The obtained product is fatty acid alkyl ester, most commonly fatty acid methyl ester (FAME). Poor low-temperature properties of FAME however limit its wider use in regions with colder climatic conditions.
Said properties are the result of the straight chain nature of the FAME molecule and thus double bonds are needed in order to create even bearable cold flow properties. Carbon-carbon double bonds and ester groups however decrease the stability of fatty acid esters, which is a major disadvantage of transesterification technology. Further, Schmidt, K., Gerpen J. V.: SAE paper 961086 teaches that the presence of oxygen in esters results in undesirable higher emissions of NOx, in comparison to conventional diesel fuels.
Undesired oxygen may be removed from fatty acids or their esters by deoxygenation reactions. The deoxygenation of bio oils and fats, which are oils and fats based on biological material, to produce hydrocarbons suitable as diesel fuel products, may be carried out by catalytic hydroprocessing, such as hydrocracking, but also more controlled hydrotreating conditions may be utilized.
During hydrotreating, particularly hydrodeoxygenation oxygen containing groups are reacted with hydrogen and removed through formation of water and therefore this reaction requires rather high amounts of hydrogen. Due to the highly exothermic nature of these reactions, the control of reaction heat is extremely important. Impure plant oil/fat or animal fat/oil, high reaction temperatures, insufficient control of reaction temperature or low hydrogen availability in the feed stream may cause unwanted side reactions, such as cracking, polymerisation, ketonisation, cyclisation and aromatisation, and coking of the catalyst. These side reactions also decrease the yield and the properties of diesel fraction obtained.
Unsaturated feeds and free fatty acids in bio oils and fats may also promote the formation of heavy molecular weight compounds, which may cause plugging of the preheating section and decrease catalyst activity and life.
The fatty acid composition, size and saturation degree of the fatty acid may vary considerably in feedstock of different origin. The melting point of bio oil or fat is mainly a consequence of saturation degree. Fats are more saturated than liquid oils and in this respect need less hydrogen for hydrogenation of double bonds. Double bonds in a fatty acid chain also promote different kinds of side reactions, such as oligomerisation/polymerization, cyclisation/aromatisation and cracking reactions, which deactivate catalyst increase hydrogen consumption and reduce diesel yield.
Plant oils/fats and animal oils/fat may contain typically 0-30% of free fatty acids, which are formed during enzymatic hydrolysis of triglycerides especially when oil seeds are kept in humid atmosphere. Free fatty acids can be also formed during purification of bio oils and fats, especially during caustic wash i.e. alkali catalyzed hydrolysis. The amount of free fatty acids present in plant/vegetable oils is typically 1-5 wt % and in animal fat 10-25 wt-%. Free fatty acids are corrosive in their nature, they can attack against materials of unit or catalyst and can promote some side reactions. Free fatty acids react very efficiently with metal impurities producing metal carboxylates, which promote side reaction chemistry.
Fatty acids may also promote the formation of heavy compounds. The boiling range of these heavy compounds is different from the range of diesel fuel and may shorten the life of isomerisation catalyst. Due to the free fatty acids contained in bio oils and fats, the formation of heavy molecular weight compounds are significantly increased compared to triglyceridic bio feeds, which have only low amount of free fatty acids (<1%).
Biological raw materials often contain metal compounds, organic nitrogen, sulphur and phosphorus compounds, which are known catalyst inhibitors and poisons inevitably reducing the service life of the catalyst and necessitating more frequent catalyst regeneration or change. Metals in bio oils/fats inevitably build up on catalyst surface and change the activity and selectivity of the catalyst. Metals can promote some side reactions, but blocking of catalyst active sites typically decreases the activity and thus metal impurities such as Na, Ca, and Mg compounds should be removed as efficiently as possible.
Hydrolysis of triglycerides produces also diglycerides and monoglycerides, which are partially hydrolyzed products. Diglycerides and monoglycerides are surface-active compounds, which can form emulsions and make liquid/liquid separations of water and oil more difficult. Bio oils and fats can also contain other glyceride-like surface-active impurities like phospholipids (for example lecithin), which have phosphorus in their structures. Phospholipids are gum like materials, which can be harmful for catalysts. Natural oils and fats also contain other types of components, such as waxes, sterols, tocopherols and carotenoids, some metals and organic sulphur compounds as well as organic nitrogen compounds. These compounds can be harmful for catalysts or pose other problems in processing.
U.S. Pat. No. 4,992,605 and U.S. Pat. No. 5,705,722 describe processes for the production of diesel fuel additives by conversion of bio oils into saturated hydrocarbons under hydroprocessing conditions with CoMo and NiMo catalysts. The process operates at high temperatures of 350-450° C. and produces n-paraffins and other hydrocarbons. The product has a high cetane number but poor cold properties (melting point>20° C.), which limits the amount of product that can be blended in conventional diesel fuels in summer time and prevent its use during winter time. The formation of heavy compounds with a boiling point above 343° C. was observed, especially when a fatty acid fraction was used as a feed. A reaction temperature with a lower limit of 350° C. was concluded as a requirement for trouble-free operation.
A two-step process is disclosed in FI 100248, for producing middle distillates from vegetable oil by hydrogenating fatty acids or triglycerides of vegetable oil origin using commercial sulphur removal catalysts, such as NiMo and CoMo, to give n-paraffins, followed by isomerising said n-paraffins using metal containing molecular sieves or zeolites to obtain branched-chain paraffins. The hydrotreating was carried out at rather high reaction temperatures of 330-450° C., preferably 390° C. Hydrogenating fatty acids at those high temperatures leads to shortened catalyst life resulting from coking and formation of side products.
EP 1 396 531 describes a process containing at least two steps, the first one being a hydrodeoxygenation step and the second one being a hydroisomerisation step utilizing counter-current flow principle, and using biological raw material containing fatty acids and/or fatty acid esters as the feedstock. The process comprises an optional stripping step.
Deoxygenation of plant oils/fats and animal fats with hydrogen use a large amount of hydrogen and at the same time releases significant amount of heat. Heat is produced from deoxygenation reactions and from double bond hydrogenation. Different feedstocks produce significantly different amounts of reaction heat. The variation of reaction heat produced is mainly dependent on double bond hydrogenation. The average amount of double bonds per triglyceride molecule can vary from about 1.5 to more than 5 depending on the source of bio oil or fat.
FR 2,607,803 describes a process for hydrocracking of vegetable oils or their fatty acid derivatives under pressure to give hydrocarbons and to some extent acid. The catalyst contains a metal dispersed on a support. A high temperature of 370° C. did not result complete oxygen removal or high selectivity of n-paraffins. The product mixture formed, contained also some intermediate fatty acid compounds.
Formation of water during hydrotreatment results from the deoxygenation of triglyceride oxygen by the means of hydrogen (hydrodeoxygenation). Deoxygenation under hydrodeoxygenation conditions is to some extent accompanied by a decarboxylation reaction pathway and a decarbonylation reaction pathway. Deoxygenation of fatty acid derivatives by decarboxylation and/or decarbonylation reactions forms carbon oxides (CO2 and CO) and aliphatic hydrocarbon chains with one carbon atom less than in the original fatty acid molecule. Decarb-reactions mean here decarboxylation and/or decarbonylation reactions.
The feasibility of decarboxylation varies greatly with the type of carboxylic acid or derivative thereof used as the starting material. Alpha-hydroxy, alpha-carbonyl and dicarboxylic acids are activated forms and thus they are more easily deoxygenated by decarb-reactions. Saturated aliphatic acids are not activated this way and generally are difficult to deoxygenate through decarb-reactions.
Decarboxylation of carboxylic acids to hydrocarbons by contacting carboxylic acids with heterogeneous catalysts was suggested by Maier, W. F. et al: Chemische Berichte (1982), 115(2), 808-12. Maier et al tested Ni/Al2O3 and Pd/SiO2 catalysts for decarboxylation of several carboxylic acids. During the reaction the vapors of the reactant were passed through a catalytic bed together with hydrogen. Hexane represented the main product of the decarboxylation of the tested compound heptanoic acid. When nitrogen was used instead of hydrogen no decarboxylation was observed.
U.S. Pat. No. 4,554,397 discloses a process for the manufacture of linear olefins from saturated fatty acids or esters, suggesting a catalytic system consisting of nickel and at least one metal selected from the group consisting of lead, tin and germanium. With other catalysts, such as Pd/C, low catalytic activity and cracking to saturated hydrocarbons, or formation of ketones when Raney-Ni was used, were observed. | {
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The invention provides a method for controlling devices within a communications network, and a system for controlling a communications network in a motor vehicle that implements the method.
The use of communications networks in motor vehicles is already known. These communications networks serve to connect controllable devices and sensors. The controllable devices in particular include infotainment devices, such as a car radio, navigation devices, and audio media player devices, without limitation.
One technology proposed for communications networks in motor vehicles is a serial bus system for operation in accordance with the IEEE 1394 standard. For such serial bus system operation, terminal devices are connected to one another by means of a 4 to 6-wire cable or by means of an optical waveguide. End pieces contained in the bus are referred to as leaves, relay nodes are referred to as branches, and the uppermost node is finally referred to as a root. This bus system is self-configuring, i.e., all nodes in the bus system send data via themselves to the other nodes. The bus management can be transferred to one or more nodes. When there are several nodes that are provided for the bus management, a competition is occurs and the winner of this competition takes over the bus management. An operating software runs on the individual nodes, which communicate with and cooperate with each other to operate the bus-attached devices as a communications network. | {
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Siloxanes are commonly included in contact lenses to improve their oxygen permeability. However, the inclusion of siloxanes can have a detrimental effect on the wettability or hydrophilicity of the lens. One suitable approach to overcome this issue is to coat or modify the contact lens surface, preferably with a biocompatible material.
Oxygen permeability of hydrophilic contact lens formulations can be improved, for example, by adding various silicon- and fluorine-containing hydrophobic monomers. Such modifications, however, may come at the expense of lens wettability and biocompatibility; for instance, materials exhibiting high gas permeabilities due to the inclusion of high levels of silicon or other strongly hydrophobic monomers frequently exhibit reduced wetting characteristics. This can lead to various problems ranging from poor lens movement on the eye, increased fouling due to lipid, protein, and/or biomolecule adherence to the lens surface, and adhesion of the lens to the eye. These and other issues can be remedied by providing a surface modification that makes the lens surface considerably more wettable.
Various techniques for improving the hydrophilicity of contact lenses have been disclosed, many of which involve a plasma treatment step. It would be desirable to have a surface modification process that did not require a separate plasma unit operation, as these techniques can be highly variable, costly, and inconvenient.
In general, various surface properties of materials, such as bioactivity, chemical reactivity, gas permeability, and wettability, can be improved by polymeric surface modifications. Other desirable features that can be enhanced or improved by surface modifications include adhesion, biocompatibility, liquid or stain resistance, lubricity, protein resistance, anti-reflective behavior, selective binding of biomolecules, and wear resistance. Although some methods of surface modification of polymers are known, it would be useful to provide improved surface modifications and processes for preparing the same. | {
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The invention is based on a priority application EP 04290524.0 which is hereby incorporated by reference.
The present invention relates to a method of inputting destination data into a navigation system as well as a mobile terminal and a navigation system used for executing this method.
A structure of a known navigation system for a car is, for example, described in U.S. Pat. No. 3,353,023.
A navigation system is composed of a processor in the form of a CPU having a plurality of inputs supplied with output signals from an azimuth direction sensor operating on the basis of terrestrial magnetism, a distance sensor for detecting a distance covered by the car by measuring the rotation numbers of a wheel and an absolute position setting sensor in the form of a radio receiver, for example a GPS receiver (GPS=Global Positioning System). Further, such navigation system has a CD-ROM storing road network data.
In operation of the navigation system, the travelling direction is detected by the azimuth direction sensor while the distance covered is detected by the distance sensor. The absolute position setting sensor receives signals from GPS satellites for determining an absolute reference position. The CPU determines the current location of the car on the basis of the output signals from the azimuth direction sensor, the distance sensor and the absolute position setting sensor while referring to the road network data stored in the CD-ROM.
Further, navigation systems are known that download via a cellular communication network data such as map data, route data and traffic data from an information service center and use such data for providing navigation services to the driver of the car.
Further, navigation system typically are equipped with input devices like a keypad for inputting route data or data about the destination of a route guided by the navigation system. But, every input made by the user holds the risk of a typing error and, due to the restricted input means of the car navigation system and the specific environmental conditions within a car, the typing of such car needs some time and makes the operation of the navigation system uncomfortable.
It is an object of the present invention to improve the data input into a navigation system. | {
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This invention relates to optical apparatus for measuring the thickness or chemical composition of partially transparent films, which are either self-supporting or attached to a reflecting substrate. Such equipment is useful in laboratory settings, and is also highly valuable for process control functions. It is particularly desired to provide an industrial coating monitor which will function on-line during the manufacturing process to measure continuously the thickness of plastic coatings on metal surfaces.
Infra-red absorption techniques have long been used to identify and analyze a wide variety of materials. In particular, techniques have been developed for determining the thickness and composition of film by measuring and comparing the transmission of radiation at two or more wavelengths. (Miller and Mounsey Paper regarding "On-Line Measurement Of Blown & Cast Film-Profile and Average Gauge Utilizing Infrared Techniques" in 1971 TAPPI Plastics-Paper Conference). Most commonly, these techniques involve a source of infrared radiation on one side of the film and a detector on the other.
There are many measurement situations in which it is either not convenient or not possible to place the source and receiver on opposite sides of the film. One example would be an organic polymer coating on an opaque substrate such as paper or metal. In such cases, it is necessary to place the detector on the same side of the target as the source and analyze the radiation which is transmitted through the coating and reflected back by the substrate. In the past, the operation of such reflective film gauges has been limited by the fact that the front surface of the coating reflects several percent of the radiation which strikes it. The radiation reflected by this first surface interferes with the radiation transmitted through the film and reflected by the substrate, in such a way as to give rise to a variation in the measured signal. This is dependent on the optical phase shift in the film and hence on both the film thickness and the wavelength of the radiation.
Designs have previously been proposed to minimize the problem of first surface reflection. For diffuse substrates such as paper, a fairly simple design has been found to be adequate (Brunton U.S. Pat. No. 3,693,025). In this case, the substrate surface is rough, whereas that of the coating is relatively smooth. As a result, the substrate reflects diffusely, i.e., in all directions; whereas the surface reflection is specular, i.e., confined to a narrow range of directions. The first surface reflection can be avoided by placing the radiation source and the detector subsystem at positions so that the optical rays between them and the surface make different angles with the normal to the surface. The specular reflection from the first surface will then miss the detector, but enough of the diffuse second surface reflection will be received to allow system operation.
Techniques have also previously been proposed for reducing the first surface effects in the case of coatings on specular substrates (Brunton U.S. Pat. No. 3,631,526). In this case, both the first and second surface reflections are specular and thus cannot be distinguished on the basis of their directionality. The three approaches proposed amount to: (1) averaging over a range of incidence angles; (2) using adjacent wavelengths; and (3) averaging over a range of wavelengths. All three of these approaches have been found experimentally to yield too little improvement to be useful for many applications of interest. The following items include all other prior art known to applicant: Brun Infra-Gauge BF-100 Brochure; Brunton U.S. Pat. Nos. 3,597,616; Brunton et al 3,790,796; and Van Horne et al 3,803,414. | {
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The ozone with strong oxidability can effectively oxidize and decompose organic pollutants, inactivate pathogenic microorganisms, and particularly inactivate cryptosporidium and giardia (G&C for short). The G&C greatly harms the public health, and the efficiency for inactivating the G&C via chlorine disinfection is very low; the United States had one of the most serious infectious events in 1993, causing that 1.5 million people were infected, 403,000 people were in sick, and nearly one hundred people died; therefore, the United States enacted a strict G&C water quality standard, and the ozonation process was rapidly applied in the United States after 1990s of the last century.
One of the most serious problems of the ozonation technical application is to sterilize the byproducts, especially the bromate can directly harm the human health. When the bromine ions with certain concentration exist in water, the bromate can be generated during the ozone oxidation process. The bromate is recognized as 2B-grade potential carcinogen by the International Agency for Research on Cancer (IARC), the drinking water standards provided by the World Health Organization, the U.S. Environmental Protection Agency (EPA) and the European Union limit the bromate standard to be 10 μg/L.
There is a positive relationship between the bromate generation and the disinfection efficiency, the problem that how to guarantee the biosafety (inactivation of G&C) and the chemical safety (bromate control) of ozonation process effluent needs to be urgently solved today as the ozonation process is increasingly popularized.
The ozone disinfection efficiency depends on the ozone concentration C and the disinfection contact time T. The complex G&C detection with long period cannot be online monitored in practical application; the inactivation efficiency depends on the CT value (product of the ozone concentration C and the disinfection contact time T) according to the disinfection dynamics, thus the CT value becomes an important basis of the disinfection efficiency. The first method of improving the CT value is to increase the ozone concentration, which means that the ozone dosage is increased, the operation cost is increased accordingly, and meanwhile the bromate generation is increased; the second method is to improve the utilization efficiency of ozone in water, which is realized by optimizing the ozone contact tank.
The ozone contact tank is a treatment structure which makes the ozone gas diffuse to the treatment water, to fully contact with the water, and to implement reaction; a high-efficient ozone contact tank can improve the disinfection efficiency, reduce the bromate generation and save the operation cost.
There are generally two methods of dissolving the ozone into water at home and abroad, one is aeration method, and the other is pipeline mixing mode. The ozone needs to maintain a certain retention period in the contact tank after dissolving in water to realize full disinfection, the best theoretical method is that the water dissolved with ozone flows through the ozone contact tank via plug flow mode. In order to realize the plug flow mode, the ozone contact tank is always designed with a vertical partition plate; a typical vertical partition plate type ozone contact tank includes multiple compartments which are connected in series to each other; the water in the compartments generally has two flow directions, namely, rising and falling directions. Such type has simple design and construction, and is easy to maintain; however, lots of researches and engineering practices show that this contact tank has quite serious short stream and back-mixing phenomenon, and low hydraulic efficiency, which can greatly influence the disinfection effect; in order to guarantee the disinfection effect, the ozone dosage must be increased, the operation cost is increased, and meanwhile, the bromate generation is increased to harm the health of residents. Thereby, the key of solving the problems of the existing ozone contact tank is to improve the flow state in the ozone contact tank to be closer to the plug flow mode, and to improve the uniform distribution degree of the ozone concentration in the water. | {
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Connectivity and voice quality are key reliability issues in today's VoIP (voice over Internet Protocol) networks. Today's VoIP users increasingly expect the Quality of Service (QoS) of the call to be equal or close to that of the Public Switched Telephone Network (PSTN). Because network conditions may change rapidly and continuously, connectivity for a VoIP call cannot be guaranteed. Further, problems that may be commonly encountered in an IP network such as packet loss, packet delay, and out of order packet delivery may lead to deteriorating quality of VoIP voice calls.
Unlike data connections, a real-time application like voice calls place much stricter requirements on packet delivery sequence and timing. Significant packet loss, packet delay, and out of order delivery problems make telephone conversations difficult. Users may experience echoes and talker overlap that are perceived as significant indicators of inferior QoS. | {
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With the spread of big data processing etc., demands for the increase in memory access speed and reduction in power consumption have been growing. The memory access speed greatly changes depending on the configuration of cache memories. The address requested an access is accessed again with high possibility, which is a property called temporal locality. Further, an address near the address requested an access is accessed with high possibility, which is a property called spatial locality. The temporal locality and spatial locality are in a trade-off relationship, and thus there is a likelihood that the spatial locality cannot be secured when emphasizing the temporal locality and the temporal locality cannot be secured when emphasizing the spatial locality. | {
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It is well established that many medically significant biological processes are mediated by proteins participating in signal transduction pathways that involve G-proteins and/or second messengers, e.g., cAMP (Lefkowitz, Nature, 1991, 351: 353-354). Herein these proteins are referred to as proteins participating in pathways with G-proteins or PPG proteins. Some examples of these proteins include the GPC receptors, such as those for adrenergic agents and dopamine (Kobilka, B. K., et al., Proc. Natl Acad. Sci., USA, 1987, 84: 46-50; Kobilka B. K., et al., Science, 1987, 238: 650-656; Bunzow, J. R., et al., Nature, 1988, 336: 783-787), G-proteins themselves, effector proteins, e.g., phospholipase C, adenyl cyclase, and phosphodiesterase, and actuator proteins, e.g., protein kinase A and protein kinase C (Simon, M. I., et al., Science, 1991, 252: 802-8).
For example, in one form of signal transduction, the effect of hormone binding is activation of the enzyme, adenylate cyclase, inside the cell. Enzyme activation by hormones is dependent on the presence of the nucleotide, GTP. GTP also influences hormone binding. A G-protein connects the hormone receptor to adenylate cyclase. G-protein was shown to exchange GTP for bound GDP when activated by a hormone receptor. The GTP carrying form then binds to activated adenylate cyclase.
Hydrolysis of GTP to GDP, catalyzed by the G-protein itself, returns the G-protein to its basal, inactive form. Thus, the G-protein serves a dual role, as an intermediate that relays the signal from receptor to effector, and as a clock that controls the duration of the signal.
The membrane protein gene superfamily of G-protein coupled receptors has been characterized as having seven putative transmembrane domains. The domains are believed to represent transmembrane .alpha.-helices connected by extracellular or cytoplasmic loops. G-protein coupled receptors include a wide range of biologically active receptors, such as hormone, viral, growth factor and neuroreceptors.
G-protein coupled receptors (otherwise known as 7TM receptors) have been characterized as including these seven conserved hydrophobic stretches of about 20 to 30 amino acids, connecting at least eight divergent hydrophilic loops. The G-protein family of coupled receptors includes dopamine receptors which bind to neuroleptic drugs used for treating psychotic and neurological disorders. Other examples of members of this family include, but are not limited to, calcitonin, adrenergic, endothelin, cAMP, adenosine, muscarinic, acetylcholine, serotonin, histamine, thrombin, kinin, follicle stimulating hormone, opsins, endothelial differentiation gene-1, rhodopsins, odorant, and cytomegalovirus receptors.
Most G-protein coupled receptors have single conserved cysteine residues in each of the first two extracellular loops which form disulfide bonds that are believed to stabilize functional protein structure. The 7 transmembrane regions are designated as TM1, TM2, TM3, TM4, TM5, TM6, and TM7. TM3 has been implicated in signal transduction.
Phosphorylation and lipidation (pamitylation or farnesylation) of cysteine residues can influence signal transduction of some G-protein coupled receptors. Most G-protein coupled receptors contain potential phosphorylation sites within the third cytoplasmic loop and/or the carboxy terminus. For several G-protein coupled receptors, such as the .beta.-adrenoreceptor, phosphorylation by protein kinase A and/or specific receptor kinases mediates receptor desensitization.
For some receptors, the ligand binding sites of G-protein coupled receptors are believed to comprise hydrophilic sockets formed by several G-protein coupled receptor transmembrane domains, said sockets being surrounded by hydrophobic residues of the G-protein coupled receptors. The hydrophilic side of each G-protein coupled receptor transmembrane helix is postulated to face inward and form a polar ligand binding site. TM3 has been implicated in several G-protein coupled receptors as having a ligand binding site, such as the TM3 aspartate residue. TM5 serines, a TM6 asparagine and TM6 or TM7 phenylalanines or tyrosines are also implicated in ligand binding.
G-protein coupled receptors can be intracellularly coupled by heterotrimeric G-proteins to various intracellular enzymes, ion channels and transporters (see, Johnson et al., Endoc. Rev., 1989, 10: 317-331). Different G-protein .alpha.-subunits preferentially stimulate particular effectors to modulate various biological functions in a cell. Phosphorylation of cytoplasmic residues of G-protein coupled receptors has been identified as an important mechanism for the regulation of G-protein coupling of some G-protein coupled receptors. G-protein coupled receptors are found in numerous sites within a mammalian host. Over the past 15 years, nearly 350 therapeutic agents targeting 7 transmembrane (7 TM) receptors have been successfully introduced onto the market.
This indicates that these receptors have an established, proven history as therapeutic targets. Clearly there is a need for identification and characterization of further receptors which can play a role in preventing, ameliorating or correcting dysfunctions or diseases, including, but not limited to, infections such as bacterial, fungal, protozoan and viral infections, particularly infections caused by HIV-1 or HIV-2; pain; cancers; diabetes, obesity; anorexia; bulimia; asthma; Parkinson's disease; acute heart failure; hypotension; hypertension; urinary retention; osteoporosis; angina pectoris; myocardial infarction; ulcers; asthma; allergies; benign prostatic hypertrophy; and psychotic and neurological disorders, including anxiety, schizophrenia, manic depression, delirium, dementia, severe mental retardation and dyskinesias, such as Huntington's disease or Gilles dela Tourett's syndrome. | {
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Phosphoric acid electrolyte baths for electrochemical decontamination have been used for several years. After long term usage, such baths show an increased iron content and activity in the electrolyte sleuthing. With iron concentrations in excess of 100 g Fe/l, further use of the electrolyte becomes uneconomical because the decontamination processes are very time consuming and labor intensive. Accordingly, the electrolyte must be discarded.
When the baths are used to decontaminate radioactive metallic articles, they become radioactively contaminated themselves and thus must be stored and contained with the precautions associated with radioactive materials.
Two principal techniques have been used heretofore for the treatment of radioactively contaminated aqueous phosphoric acid electrolytes.
In one approach the phosphoric acid electrolyte, containing about 30 to 40% phosphoric acid, is diluted some 50 times with water. This is necessary to prevent, during the subsequent neutralization with sodium hydroxide, a precipitation of the Na.sub.3 PO.sub.4.12 H.sub.2 O.
In a second step, the sodium hydroxide is added with intensive stirring to a pH of the solution of 7. During the neutralization, the previously soluble iron phosphate precipitates as a sediment from which the liquid phase is easily decanted.
The iron phosphate precipitate binds the greater part of the radioactivity to it so that the supernatent sodium phosphate solution has a radioactivity which lies below the limits which require consideration of the waste water as radioactive.
Nevertheless the water can be subjected to further sedimentation and flocculation processes. This approach has the advantage that for 3000 liters of an electrolyte bath, only about 1000 kg of iron phosphate must be subjected to conditioning and storage as a radioactive waste. Its drawback, however, is that the radioactive waste water from a 3000 electrolyte bath contains about 1800 kg of sodium phosphate which is equivalent to about 1500 kg of phosphate ion, a significant environment contaminant when this waste water is disposed of.
The more common approach, therefore, provides for evaporation concentration of the electrolyte solution. To protect the evaporator and prevent deposits from forming since the solution treated otherwise has caking tendencies, the acid must be neutralized to a solution of about pH 10. As a result, this method produces a mixture of the Na.sub.3 PO.sub.4.12 H.sub.2 and iron phosphate. For a 3000 l charge of the electrolyte bath, therefore, some 1000 kg of the dodeca hydrate of sodium authophosphate must be conditioned.
While this process is less prone to environmental contamination because of the release of phosphates, it nevertheless must deal with the storage and processing as radioactive wastes of large amounts of solid residue. | {
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The present invention relates to an amorphous silicon semiconductor and an amorphous silicon photovoltaic device.
Since it was found in 1976 by W. E. Spear et al that the conductivity of the amorphous silicon obtained by a plasma decomposition method of silane (SiH.sub.4) could be greatly altered by doping with phosphine (PH.sub.3) and diborane (B.sub.2 H.sub.6) and an amorphous silicon solar cell was fabricated on an experimental basis in 1976 by D. E. Carlson et al, the amorphous silicon solar cell has attracted attention, and many studies with the aim of improvement of its efficiency have been made.
The Schottky barrier type, PIN type, MIS type and heterojunction type are known structures of photovoltaic devices using an amorphous silicon thin film. The former three types promise to provide highly efficient solar cells. For instance, a Schottky barrier type solar cell made by D. E. Carlson et al in 1977 showed a conversion efficiency of 5.5%, an MIS type solar cell made by J. I. B. Wilson et al in 1978 showed a conversion efficiency of 4.8%, and a PIN junction solar cell made by Yoshihiro Hamakawa in 1978 showed a conversion efficiency of 4.5%.
In the case of the PIN junction solar cell, the P or N type amorphous silicon has a short carrier life time and, therefore, fails to provide effective carriers. Also, the P-layer suffers from light absorption loss because it has a higher light absorption coefficient than the I-layer. In order to eliminate these drawbacks, an inverted PIN junction photovoltaic device has been proposed. This photovoltaic device is constructed so that the light impinges on the N-type amorphous silicon side. Since this device has a smaller light absorption coefficient than the P-type, it is believed to be more advantageous, though slightly. Nevertheless this N-type amorphous silicon is no better than the P-type in the sense that it similarly suffers from light absorption loss.
Also, in the case of the PIN junction solar cell, it is necessary to form a transparent electrode on the light-impinging side, and ITO (indium-tin-oxide) (In.sub.2 O.sub.3 +SnO.sub.2) or SnO.sub.2 has been employed as a transparent electrode. However, cells with the ITO electrode have the disadvantage that while the fill factor is good, the open circuit voltage is low, and cells with the SnO.sub.2 electrode have the disadvantage that while the open circuit voltage is high, the fill factor is bad.
It is an object of the present invention to provide an amorphous silicon semiconductor suitable for use in fabricating an amorphous silicon PIN junction photovoltaic device.
Another object of the invention is to provide an amorphous silicon PIN junction photovoltaic device having an improved conversion efficiency.
It is a still further object to provide a two-layer transparent electrode on the light impinging side of an amorphous silicon type solar cell.
These and other objects of the present invention will become apparent from the description hereinafter. | {
"pile_set_name": "USPTO Backgrounds"
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It has been reported that, among high density, polycyclic insensitive molecular explosives developed in the developed countries including the United States, etc., compounds known to have most detonating power are hexanitrohexaazaisowurtzitane (HNIW) compounds having an isowurtzitane structure and octanitrocubane (ONC) having a cubane structure, and the explosive properties thereof are well-known to be considerably superior to the commercially available HMX or RDX. From the various studies conventionally made on such compounds, it has been learned that compounds having high atomic density in ring structure have an advantageous effect on the explosive properties, however, conventional methods for preparing HNIW or ONC compounds have some problems such as the requirement of complex procedure consisting of various steps or low yield. Therefore, for developing compounds having great ring strain and high atomic density such as HNIW or ONC, the present inventors have come with an idea of preparing compounds having a propellane structure that has three rings, and particularly [3.3.3]propellane was considered to be a possible candidate for suitable synthesis since it has 28 kcal/mol of ring strain energy of molecule which suggests its relatively high potential energy and −30 Kcal/mol of enthalpy (ΔHf(kcal/mol)) which means stable to synthesis. Based on this, azapropellane compounds which have a [3.3.3]propellane structure substituted with various numbers of nitrogen atoms have been considered. There are hardly examples of such azapropellane structure compounds synthesized or applied as a high energy material, and particularly for hexaaza[3.3.3]propellane there have not been any examples disclosing its synthesis or use. | {
"pile_set_name": "USPTO Backgrounds"
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Guide wires are used to guide a catheter for treatment of intravascular sites such as PTCA (Percutaneous Transluminal Coronary Angioplasty), or in examination such as cardio-angiography. For example, a guide wire used in the PTCA is inserted into the vicinity of a target angiostenosis portion together with a balloon catheter, and is operated to guide the distal end portion of the balloon catheter to the target angiostenosis portion.
A guide wire needs appropriate flexibility, pushability and torque transmission performance for transmitting an operational force from the proximal end portion to the distal end, and kink resistance (resistance against sharp bending). To meet such requirements, superelastic materials such as a Ni—Ti alloy and high strength materials have been used for forming a core member (wire body) of a guide wire.
Near equi-atomic binary nickel-titanium alloys are known to exhibit “pseudo-elastic” behavior when given certain cold working processes or cold working and heat treatment processes following hot working. Pseudo-elasticity can be further divided into two subcategories: “non-linear” pseudo-elasticity and “linear” pseudo-elasticity. “Non-linear” pseudo-elasticity is sometimes used by those in the industry synonymously with “superelasticity.”
“Non-linear” pseudo-elastic Ni—Ti alloy exhibits upwards of 8% elastic strain (fully-recoverable deformation) by virtue of a reversible, isothermal stress-induced martensitic transformation. Linear pseudo-elasticity exhibits no such flat plateau. Non-linear pseudo-elasticity is known to occur due to a reversible phase transformation from austenite to martensite, the latter more precisely called “stress-induced martensite” (SIM). At room or body temperature and under minimal stress the material assumes a crystalline microstructure structure known as austenite. As the material is stressed, it remains in the austenitic state until it reaches a threshold of applied stress (a.k.a. the “upper plateau stress”), beyond which the material begins to transform into a different crystal structure known as martensite. Upon removal of the applied stress, the martensite reverts back to the original austenite structure with an accompanying return to essentially zero strain (i.e., the original shape is restored).
A “linear” pseudo-elastic Ni—Ti alloy is processed by cold working the material (e.g., by permanently deforming the material such as by wire-drawing) without subsequent heat treatment (i.e., partial or full annealing). Residual permanent deformation, i.e., “cold work,” tends to stabilize the martensitic structure so its reversion back to austenite is retarded or altogether blocked. With increasing levels of permanent deformation, the otherwise austenitic material becomes fully martensitic at room and body temperature, and further permanent deformation serves to progressively raise its yield strength. The complete disappearance of austenite via cold work altogether eliminates the plateau (austenite to martensite transformation) on the stress strain curve, and results in a unique stress strain curve without a classic perfectly linear slope and without an apparent yield point.
While linear pseduoelastic binary NiTi is highly durable with good flexibility and pushability, binary NiTi in the linear pseduoelastic state is nevertheless not an ideal material for a guide wire due to its inherently low stiffness [i.e., secant modulus around 5 Msi (˜34 GPa) at 4% elongation versus conventional Young's modulus of approximately 28 Msi (˜193 GPa) for 316L austenitic stainless steel], which adversely affects torqueability. For example, the low modulus of the material in the martensitic condition (either linear pseudo-elastic martensite or stress-induced martensite found in superelastic Ni—Ti) relative to an austenitic stainless steel makes it challenging to torque a guide wire made from linear pseudo-elastic Ni—Ti alloy because it has a greater tendency to elastically absorb a significant amount of applied twist as opposed to directly transmitting torque from end to end. | {
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In general the present invention relates to calenders for fiber web in a fiber web machine. More especially the present invention relates to a method for modernizing a multiroll calender for a fiber web in which at least one of the calender rolls is a smooth-surfaced press-roll.
Calendering is generally carried out in order to improve the properties, like smoothness and gloss, of a web-like material such as a paper or board web. In calendering the web is passed into a calendering nip formed between rolls that are pressed against each other, in which nip the web becomes deformed as by the action of temperature, moisture and nip pressure. In the calender the nips are formed between a smooth-surfaced press roll such as a metal roll and a roll coated with resilient material such as a polymer roll. The resilient surfaced roll adjusts itself to the forms of the web surface and presses the opposite side of the web evenly against the smooth-surfaced press roll. Multinip or multiroll calendering is calendering in a calendering unit in which the nips are formed between a smooth-surfaced press roll such as a metal roll and a roll coated with resilient material such as a polymer roll and the linear load increases in multinip calenders from the upper nip to the lower nip due to gravitation, unless roll relief systems are used.
From the prior art multiroll calenders are known in which a set of rolls formed of two stacks of rolls, with each stack of rolls comprising at least two calender rolls. Multinip or multiroll calender are known for example by the brand names OptiLoad® and TwinLine™. In F1 patent 96334 is disclosed a method for calendering a paper or an equivalent web material in a calender where the web to be calendered is passed through nips formed by a deflection-compensated upper roll and a deflection-compensated lower roll, and by two or more intermediate rolls arranged between the upper and lower roll. The rolls are arranged as a substantially vertical stack of rolls. Supercalenders are multiroll calenders composed of alternating hard and soft rolls, which soft rolls are filled rolls that have a steel shaft around which a multiplicity of specialty paper sheets with a hole in the middle are slid. The paper sheets are then compressed with a hydraulic press. The most common number of rolls is 9-12, but here can be up to 16 rolls.
In publication F1 20095284 is disclosed a heatable and/or coolable roll for fiber web machines which comprises a mantle part and end pieces attached to the ends of the mantle part for arranging a feed channel and a discharge channel for a heat transfer medium in the roll. The mantle part comprises flow channels for the heat transfer medium. The mantle part of the roll comprises an inner layer and an outer layer attached on the inner layer and the flow channels for heat transfer medium comprise flow grooves formed on the outer surface of the inner layer, and the roll comprises at its first end a first circumferential flow chamber, which is in flow connection with the feed channel or the discharge channel for the heat transfer medium of the roll, wherein the roll comprises first flow bushings, which are arranged in connection with the first flow chamber such that by each first flow bushing is formed a flow connection for the heat transfer medium between the first circumferential flow chamber and the flow channel of the mantle part. Flow channels can be arranged to form a spiral shaped geometry in the mantle, thus minimizing vibration excitation from uneven thermal expansion from fluid channels.
As fiber web machine running speeds increase the need for increasing calendering capacity increases. Also the need for increasing capacity of existing calenders increases since in many prior art fiber web machines the calender, in particular the supercalender, has become the part of the fiber web production line that limits the available capacity and hinders the production of full capacity of the other parts of the fiber web production line. Due to this, in many cases two or even three supercalenders are needed for calendering the production of the fiber web production line.
The line between paper and board is flexible and paper and board are available in a wide variety of grades and can be divided according to basis weight into two categories: papers with a single ply and a basis weight of 25-300 g/m2 and boards manufactured in multi-ply technology and having a basis weight of 150-600 g/m2. It should be noted that the border line between paper and board is flexible since board grades with lightest basis weights are lighter than the heaviest paper grades. Generally speaking, paper is used for printing and board for packaging.
The subsequent descriptions are examples of some values presently applied for fibrous webs, and there may be considerable variations from the disclosed values. The descriptions are mainly based on the source publication Papermaking Science and Technology, section Papermaking Part 3, edited by Jokio, M., published by Fapet Oy, Jyvaskyla 1999, page 362.
Mechanical-pulp based, i.e. wood-containing printing papers include newsprint, uncoated magazine and coated magazine paper.
Newsprint is composed either completely of mechanical pulp or may contain some bleached softwood pulp (0-15%) and/or recycled fiber to replace some of the mechanical pulp. General values for newsprint can be regarded as follows: basis weight 40-48.8 g/m2, ash content (SCAN-P 5:63) 0-20%, PPS s10 roughness (SCAN-P 76:95) 3.0-4.5 pm, Bendtsen roughness (SCAN-P 21:67) 100-200 ml/min, density 200-750 kg/m3, brightness (ISO 2470:1999) 57-63%, and opacity (ISO 2470:1998) 90-96%.
Uncoated magazine paper (SC=supercalendered) usually contains mechanical pulp to 50-70%, bleached softwood pulp to 10-25%, and fillers to 15-30%. Typical values for calendered SC paper (containing e.g. SC-C, SC-B. SC-NM-) include basis weight 40-60 g/m2, ash content (SCAN-P 5:63) 0-35%, Hunter gloss (ISO/DIS 8254/1)<20-50%, PPS s10 roughness (SCAN-P 76:95) 1.2-2.5 pm, Bendtsen roughness (SCAN-P 21:67) 100-200 ml/min, density 700-1250 kg/m3, brightness (ISO 2470:1999) 62-70%, and opacity (ISO 2470:1998) 90-95%.
Coated magazine paper (LWC=light weight coated) contains mechanical pulp to 40-60%, bleached softwood pulp to 25-40%, and fillers and coaters to 20-35%. General values for LWC paper can be regarded as follows: basis weight 40-70 g/m2, Hunter gloss 50-65%, PPS s10 roughness 0.8-1.5 pm (offset), 0.6-1.0 pm (roto), density 1100-1250 kg/m3, brightness 70-75%, and opacity 89-94%.
General values for MFC (machine finished coated) can be regarded as follows: basis weight 50-70 g/m2, Hunter gloss 25-70%, PPS s10 roughness 2.2-2.8 pm, density 900-950 kg/m3, brightness 70-75%, and opacity 91-95%.
General values for FCO (film coated offset) can be regarded as follows: basis weight 40-70 g/m2, Hunter gloss 45-55%, PPS s10 roughness 1.5-2.0 pm, density 1000-1050 kg/m3, brightness 70-75%, and opacity 91-95%.
General values for MWC (medium weight coated) can be regarded as follows: basis weight 70-90 g/m3, Hunter gloss 65-75%, PPS s10 roughness 0.6-1.0 pm, density 1150-1250 kg/m3, brightness 70-75%, and opacity 89-94%.
HWC (heavy weight coated) has a basis weight of 100-135 g/m2 and can be coated even more than twice.
Pulp-produced, wood free printing papers or fine papers include uncoated—and coated—pulp-based printing papers, in which the portion of mechanical pulp is less than 10%.
Uncoated pulp-based printing papers (WFU) contain bleached birchwood pulp to 55-80%, bleached softwood pulp 0-30%, and fillers to 10-30%. The values with WFU have a large variation: basis weight 50-90 g/m2, Bendtsen roughness 250-400 ml/min, brightness 86-92%, and opacity 83-98%.
In coated pulp-based printing papers (WFC), the amounts of coating vary widely in accordance with requirements and intended application. The following are typical values for once and twice-coated, pulp-based printing paper: once-coated basis weight 90 g/m2, Hunter gloss 65-80%, PPS s10 roughness 0.75-2.2 pm, brightness 80-88%, and opacity 91-94%, and twice-coated basis weight 130 g/m2, Hunter gloss 70-80%, PPS s10 roughness 0.65-0.95 pm, brightness 83-90%, and opacity 95-97%.
Release papers have a basis weight within the range of 25-150 g/m2.
Other papers include e.g. sackkraft papers, tissues, and wallpaper bases.
Board making makes use of chemical pulp, mechanical pulp and/or recycled pulp. Boards can be divided e.g. in the following main groups according to applications thereof: Corrugated board, comprising a liner and fluting; Boxboards, used for making boxes, cases, which boxboards include e.g. liquid packaging boards (FBB=folding boxboard, LPB=liquid packaging board, WLC=white-lined chipboard, SBS=solid bleached sulfite, SUS=solid unbleached sulfite); Graphic boards, used for making e.g. cards, files, folders, cases, covers, etc. and wallpaper bases.
An object of the present invention is to create a method for modernizing a multiroll calender and a modernized multiroll calender in which high capacity of the production line is achieved.
Another object of the present invention is to achieve a method and a multiroll calender in which possible disadvantages and problems of known methods and calenders are eliminated or at least minimized. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to an apparatus for optically marking predetermined positions in a stack of documents or for subdividing a stack of documents or the like during the stacking operation.
If papers, documents or other flat objects are to be handled by machine, it may be advantageous to introduce markings for identifying one or more positions of the stacked documents. This may be desirable to separate predetermined numbers of pieces, to set off defective or special parts in the stack, to find a certain position again quickly, or for some other reason. To do this, it is customary to manually insert a mnemonic card which makes it easier to find this position later on. At slow processing speeds, this manual marking is quite workable and sufficient. If, however, a stack of documents is to be read, sorted and made into packages of a predetermined number of pieces by machine, manual marking of the desired positions in the stack would adversely affect the processing speed. | {
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In an effort to progressively reduce the size of and concurrently improve the functionality of a portable electronic device, novel ways of optimizing space within the portable electronic device become increasingly important. Increased and improved functionality often come in the form of additional components and/or sensors. The additional components or sensors tend to take up space in a device housing of the portable electronic device that may not be available. While reducing a size of other components can help to produce additional space, such methods can unfortunately result in reduced functionality or performance. Consequently, additional methods for optimizing space within the device housing are desired. | {
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As is well known and understood, bar codes are used by the United States Postal Service and other mail carriers in an attempt to speed up the processing of mail delivery and to reduce labor expense. As is also well known and understood, these bar codes are typically sprayed onto the mail documentation by such expensive equipment as optical character readers which first read the addresses electronically, and then converts the address into machine readable codes for further processing.
However, and as has been widely publicized, the equipment employed in such sophisticated optical-scanning technology and computer-based artificial intelligence systems experience great difficulty in deciphering street names, numbers and Zip-Codes written in pencil or pen. As has also been highly publicized, this is particularly a problem where the information is handwritten. In such instances--amounting to upwards of 30-40 percent of United States Postal Service delivery--, in order to process the mail the bar code is affixed to speed delivery; obviously, this represents both a tedious and costly task.
In an attempt to combat this, much effort has been devoted to analyzing thousands of handwritten and printing styles, to try to determine quirks and commonalities that computers can be taught to identify and interpret. As has been reported in the print media, researchers have demonstrated experimental systems that can discern enough information from a handwritten envelope to meet the needs of automated letter-sorting equipment--but these equipments have been determined to take a far longer period of time to read the address than the Postal Services desired speed of some 13 pieces of mail per second for its automated sorting machines.
As has also been widely advertised, it is the present desire of the United States Postal Service to have bar codes on all mail by the year 1995, so as to have the coding mail system completely operative by then. In view of that, much sophisticated information-technology and government-contracting corporations are proposing systems to obtain address-recognition contracts to replace or supplement the automated scanning and sorting equipment currently being used. When one factors in that such "handwritten recognition" could also be useful in the banking, credit card and/or other industries, in which large volumes of handwritten documents jam-up computer processing, it is not too hard to understand all the engineering time and effort being invested.
However, equally apparent is the lack of attention which the Postal Service has devoted to easing this problem at the "sending end," where the documents are being addressed. While admittedly, the present Postal operation gives a premium of 2 cents or more for every piece of first-class mail that is already addressed with a bar code, that fact has not been very-well publicized. In fact, by-and-large, the Postal Service has come to a seeming conclusion that nothing it can do can bring the "sending public", into the equation of facilitating the mail delivery by typewriting the envelope so that its address can be computer recognized, or by having envelopes already pre-printed with bar code destinations, as have been employed by public utility companies, credit card companies and insurance companies in processing their already addressed coupons to be returned by a consumer along with its monthly or periodic payment. | {
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1. Field of the Invention
The present invention relates to a hybridoma cell line producing a monoclonal antibody against foot-and-mouth disease virus (FMDV), the monoclonal antibody therefrom, a reagent and kit for enzyme-linked immunosorbent assay (ELISA), and an immunoassay method. More particularly, the present invention relates to a hybridoma cell line applicable to sandwich ELISA and capable of producing an anti-FMDV NSP (Non-structural protein) monoclonal antibody, the monoclonal antibody therefrom, and an immunoassay reagent and kit including the monoclonal antibody.
2. Description of the Prior Art
Foot-and-mouth disease (FMD) is one of the most contagious diseases among artiodactyla, primarily infecting farm animals such as cows, pigs, and sheep. Typical symptoms of FMD are fever, and formation of epithelial blisters and subsequent necrosis thereof affecting the mouth, tongue, nostrils, legs, and nipples. The foot-and-mouth disease virus, a positive strand RNA virus known as Aphthovirus, Picornaviridae in taxonomy, is a tiny non-enveloped virus that has 8.5 kbp of genome translatable into structural proteins (SPs) and non-structural proteins (NSPs). There are seven FMDV serotypes, known as serotypes O, A, C, Asia 1, SAT 1, SAT 2, and SAT 3 (SAT=Southern African Territories), recognized worldwide. The serotypes do not provide cross protection for each other. FMDV mutates quickly and hence presents genetic and antigenic variation between strains. VP1 structural protein on the surface of FMDV shows major neutralization activity with high plasticity and marked antigenic variation. In 1997, heath crisis of Taiwan's animal populations triggered by an outbreak of serotype O FMD epidemic; and the serotype O FMDV was named O/TAW/97. This strain is a prototype of atypical porcinophilic infection in swine. According to experiment results, the codon of a segment (93-102) within the non-structural protein region 3A of the strain is deleted and the segment is a major factor in restricting the growth and replication of the virus in bovine epithelial cells in vitro. Hence, the deletion of the virus strain is proved to be the cause of a lack in bovine susceptibility to the O/TAW/97 strain. The 1997's FMD epidemic in Taiwan caused a great economic loss (estimated at more than US$ 6 billions) because of control measures and trade restrictions. Another virus strain, which was discovered in subclinically infected cattle in Kinmen, has a gene structure with a full-length 3A non-structural protein translation region, and thus is proved to be a pernicious bovine virus strain (O/TAW/2/99). The O/TAW/2/99 strain, which is a topotype of the serotype O FMDV prevalent in southern Asia, launched its first invasion into Taiwan in 1999. Upon the FMD outbreak, the Taiwanese government took quarantine measures immediately, screened animals in the affected farms for FMDV, humanely killed any infected animals promptly, and disposed of the carcasses without delay. In addition, the Taiwanese government carried out precautionary screening of farms suspected of FMDV infection, as an action taken to confine the spread of FMDV.
The conventional ways of producing inactivated viruses have the following drawbacks: (1) With FMD being a highly contagious airborne disease, and the production of inactivated FMDV entailing the use of viruses, the laboratories where inactivated FMDV is to be produced must be Class III negative pressure laboratories conforming to corresponding bio-safety specifications, and nevertheless there is a risk that FMDV may be released in the course of production; (2) An inactivated virus cannot produce the non-structural protein which would otherwise be produced naturally by an infected living host, and in consequence a diagnostic immunoassay using the inactivated virus as antigen is unable to distinguish infected living host from vaccinated ones. | {
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It is known to mount an inflatable restraint on the hub of the steering wheel or on the instrument panel in the passenger compartment to supplement the seat belts in the event of a frontal crash. The inflatable restraint is inflated by a hot nitrogen gas generated by the ignition of a pyrotechnic device. The inflatable restraint is designed for a specific car by varying the size of the inflatable restraint, the rate and pressure of inflation, and the size of the vents in the bag which control deflation of the inflatable restraint.
Because of the large number of variables involved in the design and engineering of an effective inflatable restraints system, it would be desirable to provide an inflation apparatus and method which could be re-used repeatedly and also be readily adjusted to vary the rate and pressure of inflation of the inflatable restraints. It has been found that the use of pyrotechnic devices may not be desirable during this development and engineering effort because such devices are not reusable and considerable time and expense is required to manufacture the pyrotechnic devices which must be employed to provide inflation gases at varying rates and pressures.
Therefore it would be desirable to provide an apparatus and method by which readily available compressed gases could be employed to simulate the inflation rates and pressures ordinarily obtained from the hot gas generated by the pyrotechnic devices. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to an optical head apparatus for detecting a radial tilt of an optical recording medium and an optical information apparatus for performing at least one of recording and reproducing operations using such an optical head apparatus.
2. Description of the Related Art
Generally, in an optical recording medium such as a recordable or a rewritable optical disk, a tracking groove is formed in advance only for a tracking operation. That is, a tracking error signal is calculated by the tracking groove using a push-pull method, so that the location of an objective lens is changed in accordance with the tracking error signal. In this case, if the objective lens is shifted in the radial direction of the optical recording medium, a so-called lens radial shift offset occurs in the tracking error signal.
A first prior art optical head apparatus is known to reduce the above-mentioned lens radial shift offset, thus suppressing the deterioration of the read/write characteristics due to the lens radial shift offset (see: JP-A-2000-082226).
On the other hand, in an optical recording and reproducing apparatus including an optical head apparatus, the recording density is inversely-proportional to the square value of the diameter of focused spots formed on an optical recording medium. That is, the smaller the diameter of focused spots, the larger the recording density. Also, the diameter of focused spots is inversely-proportional to the numerical aperture of an objective lens. That is, the larger the numerical aperture of the objective lens, the smaller the diameter of focused spots.
When the optical recording medium is inclined in the radial direction with respect to the objective lens, the configuration of focused spots fluctuates due to the coma aberration arisen from the inclination of the optical recording medium in the radial direction which is called a radial tilt, so that the read/write characteristics deteriorate. The coma aberration is proportional to the cubic value of the numerical aperture of the objective lens. That is, the larger the numerical aperture of the objective lens, the narrower the margin of the radial tilt of the optical recording medium for the read/write characteristics. Therefore, in an optical recording and reproducing apparatus having an optical head apparatus with a larger numerical aperture objective lens, it is required to detect and compensate for a radial tilt of the optical recording medium.
A second prior art optical head apparatus is known to detect and compensate for a radial tilt of an optical recording medium (see: Ryuichi Katayama et al., “Substrate Thickness Error and Radial Tilt Detection Using 5-Beam Optical Head”, Optical Data Storage Topical Meeting 2001, pp. 97-99, April 2001). This will be explained later in detail.
In the above-described first prior art optical head apparatus, it is impossible to detect and compensate for a radial tilt of the optical recording medium.
On the other hand, in the above-described second prior art optical head apparatus, it is impossible to reduce the lens radial shift offset in the tracking error signal, so that the read/write characteristics deteriorate. Also, since five focused beams each requiring four photodetecting portions, i.e., twenty photodetecting portions are used, a control unit including current-to-voltage conversion circuits connected to the photodetecting portions and calculating circuits becomes complex, which would increase the manufacturing cost.
A third prior art optical head apparatus is known to reduce the lens radial shift offset in the tracking error signal as well as to detect and compensate for a radial tilt of the optical recording medium(see: Ryuichi Katayama et al. “Radial Tilt Detection Using 3-Beam Optical Head”, Proceedings of SPIE, Vol. 4090, pp. 309-318, 2000). That is, three focused beams i.e., a main beam and two sub beams are used, and two photodetectors are required for each of the three focused beams.
In the above-described third prior art optical head apparatus, however, since a radio frequency (RF) signal is obtained from only one photodetector for the main beam, the signal-to-noise (S/N) ratio of the RF signal is low. | {
"pile_set_name": "USPTO Backgrounds"
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The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
A current design class of multiple speed automatic transmissions comprehends a plurality of planetary gear assemblies having their sun gears, planet carriers and ring gears interconnected by permanent connections and selectively connected by clutches or grounded by brakes. The clutched and brakes are generally engaged or activated by hydraulic fluid pressure.
The speed and force with which the clutches and brakes can, should or must be engaged is a major factor in the performance of such transmissions and is the subject of much study. If speed is the more significant design parameter, the clutch piston can be made smaller such that a typical flow of pressurized fluid will quickly move the piston. On the other hand, if force is more important, the clutch piston may be made larger (have a larger area). While it will obviously not move as quickly, given the same pressurized fluid flow provided to a smaller piston, it will be capable of generating higher force.
An acknowledged engineering compromise to this problem is a clutch engaged or activated by a dual area piston. The flow of pressurized hydraulic fluid is provided to a modulating control valve and thence to a shift valve which directs the modulated flow of fluid to the selected larger or smaller area of the piston. Thus, by incorporation and control of the shift valve, a single clutch and piston can produce rapid, low force movement utilizing the smaller area of the piston and slower, higher force movement utilizing the larger area of the piston.
In practice, however, this approach has revealed a shortcoming. In certain shift situations, it is necessary to reposition the shift valve in the middle of a shift. Whenever this is done, the pressure level on one side is immediately transferred to the other. When this occurs during a shift, poor torque capacity control may result.
Thus it is apparent that improvements in dual area clutches and actuating systems for use in automatic transmissions are desirable. | {
"pile_set_name": "USPTO Backgrounds"
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Programmable logic devices (PLDs) are a well-known type of integrated circuit that can be programmed to perform specified logic functions. One type of PLD, the field programmable gate array (FPGA), typically includes an array of programmable tiles. These programmable tiles can include, for example, input/output blocks (IOBs), configurable logic blocks (CLBs), dedicated random access memory blocks (BRAM), multipliers, digital signal processing blocks (DSPs), processors, clock managers, delay lock loops (DLLs), and so forth.
Each programmable tile typically includes both programmable interconnect and programmable logic. The programmable interconnect typically includes a large number of interconnect lines of varying lengths interconnected by programmable interconnect points (PIPs). The programmable logic implements the logic of a user design using programmable elements that can include, for example, function generators, registers, arithmetic logic, and so forth.
The programmable interconnect and programmable logic are typically programmed by loading a stream of configuration data (a configuration bitstream) into internal configuration memory cells that define how the programmable elements are configured. The configuration data can be read from memory (e.g., from an external PROM) or written into the FPGA by an external device. The collective states of the individual memory cells then determine the function of the FPGA.
FPGAs are called “field programmable” because the configuration data is written to the device each time the device is powered up (i.e., the device is programmed in the field). Other field programmable PLDs include Complex Programmable Logic Devices (CPLDs), for example, to which configuration data can be written once and the device remains configured until the configuration data is erased or overwritten. Thus, a CPLD can be programmed by the CPLD provider, the customer, or both. Other field programmable PLDs can include, but are not limited to, anti-fuse and fuse devices. Some PLDs are only partially programmable. For example, one type of PLD includes a combination of hard-coded transistor logic and a programmable switch fabric that programmably interconnects the hard-coded transistor logic.
FIG. 1 is a simplified illustration of an exemplary FPGA. The FPGA of FIG. 1 includes an array of configurable logic blocks (LBs 101a-101i) and programmable input/output blocks (I/Os 102a-102d). The LBs and I/O blocks are interconnected by a programmable interconnect structure that includes a large number of interconnect lines 103 interconnected by programmable interconnect points (PIPs 104, shown as small circles in FIG. 1). PIPs are often coupled into groups (e.g., group 105) that implement multiplexer circuits selecting one of several interconnect lines to provide a signal to a destination interconnect line or logic block. As noted above, some FPGAs also include additional logic blocks with special purposes (not shown), e.g., DLLs, block RAM, and so forth.
As with any other integrated circuit, a field programmable PLD can include manufacturing defects. A defect too small to see can render a PLD completely or partially nonfunctional. PLD technology trends include rapidly increasing logic density. Thus, PLDs are manufactured using a very small feature size, and a tiny defect is more and more likely to impinge on active logic on the silicon surface of a die. Another important trend is a rapid increase in die size. As PLDs increase in size, the likelihood of a given die including a defect increases dramatically.
If a PLD die contains a single defective resource (e.g., if one of the configuration memory cells in an FPGA is defective), the PLD can render a user's end product unusable, because the user design might need to use that defective resource. To avoid causing problems for end users, a PLD provider generally discards a PLD if it contains even one defect that affects the active logic. Thus, a natural consequence of the increases in PLD size and density is an increase in the percentage of defective die, or a decrease in product yield.
The problem of low yield has significant economic impact on PLD providers. There are two types of defects: gross defects (which cause the failure of an entire PLD) and localized defects (which cause the failure of small portions of the PLD circuitry). It is common to discard large numbers of PLD dice that include only localized defects. Therefore, it is desirable to provide methods for using PLDs having localized defects (“partially defective PLDs”) to implement user designs.
One known method for using partially defective PLDs is to sort out those PLDs that are defective only in an isolated function. For example, an FPGA provider can set aside all of those FPGAs in which only the block RAM is defective. If a user design does not use the block RAM, the design will still function correctly when implemented in one of these FPGAs. The FPGA provider can sell these partially defective devices to the customer at a reduced price, as an alternative to discarding them.
However, in FPGAs, for example, many defects occur in the large CLB arrays that can occupy the majority of the die. The CLBs are largely identical to each other, and each CLB can be programmed to perform any of a very large number of functions. Therefore, it is very difficult if not impossible to look at a user design and say with confidence that the implementation software will not use a given CLB to implement the design.
Further, when the design is implemented, the location of the defective CLBs is generally unknown, and is different for each partially defective PLD. Hence, when a single user design is targeted to a large number of partially defective PLDs (e.g., when a user wants to use partially defective PLDs in production to reduce the selling price of the end product), it can be difficult to ensure that the implemented design will not impinge on defective locations in any of the partially defective PLDs.
Therefore, it is desirable to provide additional methods enabling the utilization of partially defective PLDs. | {
"pile_set_name": "USPTO Backgrounds"
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Stainless bearing steels having high hardness levels (e.g., Rc 57-62) required for wear and fatigue resistance unfortunately suffer from limited fracture toughness. This is of particular concern in bearing applications requiring support of tensile stresses in the bearing as, for example, in the bearing races of the high speed fuel and oxidizer turbopumps of the main engine of the space shuttle. In these turbopumps, Type 440C stainless steel ball bearings/bearing races (hardness Rc 59) are used to support shafts rotating at 29,000 rpm at a temperature below minus 300.degree. F.
In addition to high loads and low temperatures, the turbopump bearings are also subjected to hostile lubrication conditions aggravate by the corrosiveness of the liquid oxygen supplied by the turbopump to the main engine. Corrosion, in particular stress corrosion cracking, of the bearings is thus an additional concern.
The Type 440C stainless steel bearings of the high speed fuel and oxidizer pumps were designed for a service life of 55 shuttle flights before replacement. The combination of low stress corrosion resistance and low fracture toughness (e.g., 22-23 KSI in..sup.1/2 at room temperature) of the Type 440C bearing material make bearing race cracking a serious concern. As a result, the bearings are now inspected and tested thoroughly after each shuttle flight and are replaced, if necessary. This inspection and premature replacement of the bearings has become a significant source of delay and expense between shuttle flights.
There is a need for a stainless steel having improved fracture toughness and corrosion resistance at a given high hardness level (e.g., at least Rc 59) needed for service as a bearing material in the aforementioned shuttle high speed fuel and oxidizer turbopumps as well as in other service applications where load, temperature and/or corrosion conditions require a combination of high hardness (e.g., at least Rc 57) for wear and fatigue resistance, fracture toughness, and corrosion resistance. | {
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This invention relates to a process for producing a silicon carbide single crystal by allowing a vapor evaporated from a silicon raw material to react with a carbon material, and an apparatus for producing a silicon carbide single crystal. More particularly, it relates to a process for producing a silicon carbide single crystal by passing a vapor evaporated from a silicon raw material through a carbon member and bringing the vapor into contact with a seed crystal to thereby allow the silicon carbide single crystal to grow.
By the present invention, a high-quality and large-size silicon carbide single crystal can be produced continuously at a high rate under stabilized conditions.
Silicon carbide is a semiconductor material characterized as being thermally and chemically very stable and having a wide electronic energy band gap, and is used as a material for an environment-resistant element, a radiation-resistant element, a power element for controlling an electric power, and a short-wavelength light emitting element, which can be used even under high-temperature conditions.
A silicon carbide single crystal is usually produced by a sublimation technique (For example, see Japanese Patent Publication (Kouhyou) No. H3-501118). In the sublimation technique, a powdery silicon carbide raw material and a seed crystal are placed in a graphite crucible so as to confront each other and heated to a temperature of 1,800 to 2,400xc2x0 C. in an inert gas atmosphere. By the heating, the powdery silicon carbide raw material is decomposed and sublimed, and chemical species generated by sublimation reach the surface of the seed crystal maintained at a growth temperature where silicon carbide epitaxially grows as a single crystal. The composition of the sublimation vapor during the growth of a single crystal varies depending upon factors such as the decomposition and sublimation process of the silicon carbide crystal raw material, interaction among sublimation vapor components in the vapor phase, and contact reaction of silicon carbide with graphite on the inner wall of the reaction device. Proposals for suppressing the variation have been made which include, for example, a method of incorporating a silicon component or a carbon component in the powdery silicon carbide raw material, and a method of coating the inner wall of a crucible with tantalum.
To produce a silicon carbide single crystal having an enhanced crystallizability and homogeneity, a sublimation process using a powdery silicon carbide raw material with a high purity prepared by allowing silicon to react with carbon has been proposed (Japanese Unexamined Patent Publication No. H6-316499).
The decomposition and sublimation vapor generated from a powdery silicon carbide contains Si, Si2C, SiC2 and others. As the amount of silicon components in the sublimation vapor is equimolar or more to the amount of carbon components, the composition of the powdery raw material gradually varies so that the amount of carbon increases. Thus, the partial pressure of the species contained in the sublimation vapor varies with time in the course of sublimation. The change in the composition of the sublimation vapor during the growth of the single crystal leads to reduction of crystallizability such as a crystal defect and a polymorphic mixing. A matter of importance is how to control these variation factors. In the process of crystallization into a silicon carbide crystal, various chemical species in the sublimation vapor naturally take different reaction routes. The reaction routes taken are considered to greatly depend on factors such as temperature of the raw material, variation of temperature distribution, reaction scheme of decomposition of silicon carbide raw material, and variation with time of the composition of raw material and others. These factors are difficult to control and therefore a silicon carbide single crystal having a high quality is difficult to prepare under stabilized conditions. The content of silicon in the vapor phase is liable to decrease in the course of growth of a single crystal as mentioned above, and thus, when the crystal growth is continued over a long period of time, deposition of a silicon carbide single crystal stops due to shortage of silicon in the vapor phase. Also, the composition of the powdery silicon carbide raw material varies so that the content of silicon decreases with time and finally the deposition of a silicon carbide single crystal stops. When the deposition of the single crystal stops, sublimation residue of the powdery silicon carbide raw material must be disposed. Therefore utilization efficiency of raw material in low and a continuous production is difficult to conduct. In addition, a powdery silicon carbide raw material having a high purity which is suitable for a single crystal with a high purity and a high quality used for semiconductors is difficult to prepare and is expensive.
A method of reacting silicon vapor with carbon to allow a silicon carbide single crystal to grow is known. As examples of such method, there can be mentioned (1) a method wherein silicon to used as a raw material, and silicon vapor evaporated from the silicon raw material within a graphite crucible is fed into a silicon carbide deposition chamber where the silicon vapor is brought into contact with carbon vapor generated from a graphite inner wall of the chamber whereby a silicon carbide single crystal grows (Japanese Examined Patent Publication No. S51-8400); (2) a method wherein silicon vapor as a raw material is brought into contact with a carbon plate to deposit a silicon carbide single crystal (U.S. Pat. No. 3,147,159); and (3) a method wherein silicon is used as a raw material, and silicon vapor evaporated therefrom within a graphite reaction tube is allowed to react with carbon vapor evaporated from the inner wall of the graphite reaction tube, to deposit a silicon carbide membrane on a silicon carbide single crystal plate placed within the graphite reaction tube (British Patent No. 1,031,783).
In the methods described in Japanese Examined Patent Publication No. S51-8400 and U.S. Pat. No. 3,147,159, growth of silicon carbide crystals proceeds on naturally occurring nuclei of silicon carbide crystal on the graphite wall, and a multiplicity of single crystals in a leaf form are formed, and thus, a silicon carbide single crystal having a large size cannot be obtained.
In the method described In British Patent No. 1,031,783, the composition of the vapor phase can be maintained at constant, but, the contact area of silicon vapor with the inner wall of the reactive tube is small, and thus, the growth rate of silicon carbide single crystal is low, i.e., not higher than 0.3 mm/hr. Further, because the reactive tube itself is a raw material, the quantity of raw material is restricted and a single crystal having a large size cannot be produced. And, because continuous supply of a raw material cannot be affected in said method, it cannot be adopted for a process for producing a bulk single crystal.
In view of the problems of the foregoing prior art, an object of the present invention is to provide a process for producing a silicon carbide single crystal having a large size and high quality in a continuous manner, at a high rate and under stabilized conditions.
Another object is to provide an apparatus suitable for carrying out the above-mentioned production process.
To achieve the above-mentioned objects, the inventors have conducted extensive researches into a method for evaporating silicon to react with carbon to allow a silicon carbide single crystal to grow. As the results of the researches, it was found that a silicon carbide single crystal having high quality and a large size can be grown at a high rate by using high-purity silicon and carbon as raw materials, situating a seed crystal, making larger the contact area between silicon vapor and carbon and conducting the crystal growth under appropriate pressures. The present invention has been completed based on this finding.
Thus, in accordance with the present invention, there is provided a process for producing a silicon carbide single crystal wherein a silicon carbide single crystal in allowed to grow on a seed crystal substrate, characterized by allowing a vapor evaporated from a silicon raw material to pass through a heated carbon member and reach the seed crystal substrate.
Further, in accordance with the present invention, there is provided an apparatus for producing a silicon carbide single crystal comprising a reaction tube, a heating device and a graphite crucible situated in the reaction tube, characterized in that the lower part of the graphite crucible constitutes a silicon raw material-charging part; a seed crystal substrate is situated at the top of the graphite crucible; and a carbon member, through which a vapor evaporated from the silicon raw material is capable of passing, is disposed at an intermediate position between the silicon raw material-charging part and the seed crystal. | {
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The present invention relates to secondary battery (lithium battery) for vehicle or for power supply, particularly to a multi-series battery control system for managing the condition of the secondary battery (lithium battery).
In order to solve a problem that higher precision voltage sensing involves cost increase of insulation means installed for each of multiple lower control units, there has been proposed a storage battery unit aiming at cost reduction by reducing the number of insulation means, for example, refer to Japanese Patent Laid-open 2003-70179, especially pages 3-4, FIG. 1. This Patent Document aims to lower the effect of disturbance such as noise and thereby improve reliability and enable higher precision voltage sensing. | {
"pile_set_name": "USPTO Backgrounds"
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The inventive concept relates to semiconductor devices and methods of fabricating semiconductor devices, and more particularly, to methods of fabricating a semiconductor device including a gate electrode filling a trench.
When the channel length of a semiconductor devices, such as a dynamic random access memory (DRAM), is reduced, it is difficult to prevent short channel effects and source/drain punch-through. In addition, an amount of leakage current may be increased, which may reduce the refresh time of a DRAM. To address these problems, recess channel array transistors have been introduced. When a recess channel array transistor is used in a DRAM, cell bit lines and gate electrodes of a peripheral circuit are formed simultaneously. Errors may occur in semiconductor devices due to a step difference between a region where bit-line contact plugs are formed and a region where bit-line contact plugs are not formed. | {
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1. Field of the Invention
The invention relates to a method of detecting an integrated circuit in failure among a plurality of integrated circuits, and more particularly to a method of doing so, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit.
The invention relates also to an apparatus for detecting an integrated circuit in failure among a plurality of integrated circuits, and more particularly to an apparatus for doing so, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit.
The invention relates further to a recording medium readable by a computer, storing a program therein for causing a computer to either carry out the above-mentioned method or act as the above-mentioned apparatus.
2. Description of the Related Art
A method of detecting an integrated circuit in failure among integrated circuits has usually been carried out in order to detect and remove integrated circuits which are not capable of performing desired operations due to defectiveness in fabrication steps, and ship only integrated circuits which can properly operate.
For instance, the inventor had suggested a method of detecting an integrated circuit in failure in Proceedings of the 1998 IEICE General Conference C-12-8 xe2x80x9cDiagnosis of failure in an integrated circuit by analysis of a current with power spectrumxe2x80x9d. In this method, a current running through an integrated circuit while the integrated circuit is in operation is analyzed with respect to a frequency, to thereby detect an abnormal current caused by defectiveness in fabrication step.
Japanese Unexamined Patent Publication No. 9-33604 has suggested a method of identifying a failure mode, comprising the steps of detecting a logic operation test pattern in which a power source current abnormally runs through CMOS logic circuit, which is one of internal circuits of an integrated circuit, in an amount greater than a predetermined amount while the CMOS logic circuit stops its logic operation, when a logic operation test pattern is input into the CMOS logic circuit through an input terminal thereof, extracting a characteristic between a power source voltage and a power source current with the detected logic operation test pattern being input into the CMOS logic circuit, and comparing the thus extracted characteristic between a power source voltage and a power source current to similarity between a failure mode and data between a power source voltage and a power source current, stored in a database, to thereby identify a failure mode occurring in the CMOS logic circuit.
Japanese Unexamined Patent Publication No. 9-211088 has suggested a method of detecting a failure in CMOS integrated circuit by observing a static power source current independent of switching of a transistor, among a current running through CMOS integrated circuit when a test pattern is applied to CMOS integrated circuit. The suggested method is carried out in an apparatus including means for repeatedly applying a test pattern to CMOS integrated circuit under test, means for measuring a power source current supplied to CMOS integrated circuit under test, and means for measuring power spectrum of the detected power source current. The method includes the step of judging whether CMOS integrated circuit is in failure or not by observing a magnitude of power having a predetermined frequency band, among the power spectrum of the power source current.
Japanese Unexamined Patent Publication No. 10-301843 has suggested a data processor comprising a main memory including a plurality of memories, and a plurality of processors transmitting a plurality of requests of data transfer to the main memory for each unit of data, and processing data transmitted from the main memory. The plurality of memories include means for detecting bank competition which occurs by the requests transmitted from the processors, and transmit a bank competition signal to the processors, and a circuit measuring a period of time during which bank competition occurs, based on the bank competition signal.
Japanese Unexamined Patent Publication No. 11-2663 has suggested a method of detecting a failure in CMOS integrated circuit by observing a static power source current running CMOS integrated circuit when a series of test patterns is repeatedly applied to CMOS integrated circuit from LSI tester. The method includes the steps of repeatedly applying test patterns to an integrated circuit under test and a reference integrated circuit which is identical with the integrated circuit under test and is not in failure, measuring a difference between a current running through the integrated circuit under test and a current running through the reference integrated circuit, and judging whether the integrated circuit under test is in failure or not, based on a magnitude of spectrum component having a repetition frequency at which the test patterns are repeated.
Japanese Unexamined Patent Publication No. 11-94917 has suggested a method of testing a semiconductor device on which CMOS circuit is mounted, comprising the steps of inputting a clock signal into the semiconductor device, and calculating a maximum operating frequency on the basis of an inverse number of a delay time during which a power source current starts increasing at a clock operation timing and then becomes steadily equal to zero.
However, the above-mentioned methods are all accompanied with a problem that a reference, that is, data about a power source current of an integrated circuit having no failure has to be prepared in advance in order to test integrated circuits under test.
It is quite difficult to prepare such a reference. The reason is as follows. Data about a power source current is analog data, and is much influenced by processing conditions in fabrication of an integrated circuit. As a result, there is slight fluctuation among data about a power source current of integrated circuits having no failures. Hence, it is quite difficult to define a reference to be used for testing integrated circuits as to whether they are in failure or not.
In view of the above-mentioned problem, it is an object of the present invention to provide a method of detecting an integrated circuit in failure among integrated circuits, without preparing a reference, that is, data about a power source current of an integrated circuit having no failures, by utilizing data about a power source current of integrated circuits under test.
It is also an object of the present invention to provide an apparatus for doing the same.
Another object of the present invention is to provide a recording medium readable by a computer, storing a program therein for causing a computer to carry out the above-mentioned method or act as the above-mentioned apparatus.
In one aspect of the present invention, there is provided a method of detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the method including the steps of (a) assuming that all integrated circuits under test define a under-test integrated circuit set, and testing each one of the integrated circuits in the under-test integrated circuit set in a conventional manner, (b) removing integrated circuits having been judged to be in failure in the step (a), from the under-test integrated circuit set, (c) measuring spectrum of a current supplied from a power source into each one of the integrated circuits in the under-test integrated circuit set, (d) calculating both a mean value and standard deviation of the spectrum for the under-test integrated circuit set, (e) judging whether an integrated circuit is in failure or in no failure, based on both the mean value and the standard deviation of the spectrum, (f) removing integrated circuits having been judged to be in failure in the step (e), from the under-test integrated circuit set, and (g) judging the under-test integrated circuit set to be in no failure.
It is preferable that the method further includes the step (h) of normalizing the spectrum, the step (h) being to be carried out subsequently to the step (c).
It is preferable that the step (h) further includes the steps of (h1) summing up spectrum for all frequencies to have a total, and (h2) calculating a ratio of spectrum for each one of frequencies to the total.
It is preferable that the step (e) further includes the steps of (e1) calculating a gap between the spectrum and the mean value, (e2) dividing the gap by the standard deviation, (e3) comparing a quotient obtained in the step (e2) to a predetermined value, and (e4) judging an integrated circuit to be in failure, if the quotient is greater than the predetermined value, and judging an integrated circuit to be in no failure, if the quotient is equal to or smaller than the predetermined value.
There is further provided a method of detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the method including the steps of (a) assuming that all integrated circuits under test define a under-test integrated circuit set, and testing each one of the integrated circuits in the under-test integrated circuit set in a conventional manner, (b) removing integrated circuits having been judged to be in failure in the step (a), from the under-test integrated circuit set, (c) measuring spectrum of a current supplied from a power source into each one of the integrated circuits in the under-test integrated circuit set, (d) calculating a mean value and standard deviation of the spectrum for the under-test integrated circuit set, (e) checking whether the standard deviation is equal to or smaller than a predetermined value, (f) removing an integrated circuit having specific spectrum determined based on the mean value, from the under-test integrated circuit set, if the standard deviation is greater than the predetermined value, and repeating the steps (d), (e) and (f), and (g) judging the under-test integrated circuit set to be in no failure, if the standard deviation has been judged to be equal to or smaller than the predetermined value in the step (e).
It is preferable that the method further includes the step (h) of normalizing the spectrum, the step (h) being to be carried out subsequently to the step (c).
It is preferable that the step (h) further includes the steps of (h1) summing up spectrum for all frequencies to have a total, and (h2) calculating a ratio of spectrum for each one of frequencies to the total.
It is preferable that the step (f) further includes the steps of (f1) calculating a gap between the spectrum and the mean value for each one of frequencies, (f2) identifying an integrated circuit having a maximum gap among gaps calculated in the step (f1), and (f3) removing the integrated circuit identified in the step (f2), from the under-test integrated circuit set.
There is still further provided a method of detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the method including the steps of (a) testing integrated circuits to find an integrated circuit in no failure, (b) measuring spectrum of a current supplied from a power source into the integrated circuit, (c) judging the integrated circuit to be in failure, (d) repeating the steps (a) to (c) until spectrum is measured for N integrated circuits wherein N is a predetermined integer, (e) calculating a mean value and standard deviation for each frequencies with respect to the spectrum of the N integrated circuits, (f) judging whether the spectrum is abnormal or not, based on the mean value and the standard deviation, (g) deleting data of spectrum having been judged abnormal in the step (f), and repeating the steps (a) to (f), (h) defining the mean value and the standard deviation as a reference, (i) testing integrated circuits to find an integrated circuit in no failure, (j) measuring spectrum of a current supplied from a power source into the integrated circuit, (k) judging whether the spectrum is abnormal or not, based on the reference, and judging an integrated circuit to be either in no failure if the spectrum is abnormal or in failure if the spectrum is not abnormal, (l) carrying out the steps (i) to (j) for integrated circuits not tested yet, (m) defining integrated circuits having been judged to be in failure as integrated circuits not tested yet, and (n) repeating the steps (i) to (l).
It is preferable that the step (k) further includes the step of updating the reference, based on data of the spectrum.
It is preferable that the method further includes the step (o) of normalizing the spectrum, the step (o) being to be carried out subsequently to at least one of the steps (b) and (j).
It is preferable that the step (o) includes the steps of (o1) summing up spectrum for all frequencies to have a total, and (o2) calculating a ratio of spectrum for each one of frequencies to the total.
It is preferable that the method further includes the step (o) of normalizing the spectrum, the step (o) being to be carried out subsequently to at least one of the steps (b) and (j).
It is preferable that the step (o) includes the steps of (o1) summing up spectrum for all frequencies to have a total, and (o2) calculating a ratio of spectrum for each one of frequencies to the total.
It is preferable that the step (f) further includes the steps of (f1) calculating a gap between the spectrum and the mean value, (f2) dividing the gap by the standard deviation, (f3) comparing a quotient obtained in the step (f2) to a predetermined value, and (f4) judging the spectrum to be abnormal, if the quotient is greater than the predetermined value, and judging the spectrum not to be abnormal, if the quotient is equal to or smaller than the predetermined value.
It is preferable that the spectrum is judged not abnormal if the spectrum is equal to or smaller than the reference, and is judged abnormal if the spectrum is greater than the reference, in the step (k).
There is yet further provided a method of detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the method including the steps of (a) measuring spectrum of some of integrated circuits among integrated circuits under test, to thereby establish a reference, and (b) comparing the rest of integrated circuits among integrated circuits under test, to the reference to thereby judge whether each one of the rest of integrated circuits is in failure or not.
It is preferable that the method further includes the step of (c) judging whether the some of integrated circuits are in failure or not, based on the reference.
It is preferable that the method further includes the steps of (c) assuming that the some of integrated circuits are all in failure, and (d) judging again whether integrated circuits which have been judged to be in failure are in failure or not, after all integrated circuits have been judged as to whether they are in failure or not.
In another aspect of the present invention, there is provided an apparatus for detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the apparatus including (a) a tester which tests an integrated circuit in a conventional manner as to whether the integrated circuit is in failure or not, (b) a spectrum measurement unit which measures spectrum of the integrated circuit, (c) a first memory storing the spectrum therein, (d) a calculator calculating both a mean value and standard deviation of spectrum of all integrated circuits under test, based on the spectrum stored in the first memory, and (e) a controller which judges whether an integrated circuit is in failure or in no failure, based on both the mean value and the standard deviation of the spectrum.
It is preferable that the controller judges whether an integrated circuit is in failure or in no failure, based on comparison between a value defined as G/SD and a threshold value, wherein G indicates a gap between the spectrum and the mean value, and SD indicates the standard deviation.
It is preferable that the controller judges an integrated circuit to be in failure, if the value is greater than the threshold value, and judges an integrated circuit to be in no failure, if the value is equal to or smaller than the threshold value.
It is preferable that the apparatus further includes a second memory in which the threshold value is to be stored.
It is preferable that the controller judges that an integrated circuit having a maximum G/SD is in failure, when the standard deviation is greater than the threshold value.
It is preferable that the apparatus further includes a normalizer which normalizes the spectrum and replaces the previous spectrum with the normalized spectrum.
There is further provided an apparatus for detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the apparatus including (a) a tester which tests an integrated circuit in a conventional manner as to whether the integrated circuit is in failure or not, (b) a spectrum measurement unit which measures spectrum of the integrated circuit, (c) a first memory storing the spectrum therein, and (d) a controller which establishes a reference, based on spectrum of the predetermined number of integrated circuits under test, and judges whether an integrated circuit is in failure or in no failure, by comparing spectrum of each one of the integrated circuits under test to the reference.
It is preferable that the controller updates the reference, based on spectrum of an integrated circuit having been judged to be in no failure.
There is still further provided an apparatus for detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the apparatus including (a) a logic tester which tests an integrated circuit in a conventional manner as to whether the integrated circuit is in failure or not, (b) a spectrum measurement unit which measures spectrum of the integrated circuit, (c) a first memory storing the spectrum therein, (d) a calculator calculating both a mean value and standard deviation of spectrum of all integrated circuits under test, for each of frequencies, based on the spectrum stored in the first memory, and (e) a controller which judges whether an integrated circuit is in failure or in no failure, based on both the mean value and the standard deviation of the spectrum.
There is yet further provided an apparatus for detecting an integrated circuit in failure among integrated circuits, based on spectrum which is a result of analyzing a frequency of a current running through an integrated circuit when a test signal is applied to the integrated circuit, without preparing data of an integrated circuit in no failure, as a reference, the apparatus including (a) a logic tester which tests an integrated circuit in a conventional manner as to whether the integrated circuit is in failure or not, (b) a spectrum measurement unit which measures spectrum of the integrated circuit, (c) a first memory storing the spectrum therein, (d) a calculator calculating both a mean value and standard deviation of spectrum of all integrated circuits under test, for each of frequencies, based on the spectrum stored in the first memory, and (e) a controller which establishes a reference, based on spectrum of the predetermined number of integrated circuits under test, and judges whether an integrated circuit is in failure or in no failure, by comparing spectrum of each one of the integrated circuits under test to the reference.
It is preferable that the apparatus further includes (f) a first container for containing therein integrated circuits not tested yet, (g) a second container for containing therein integrated circuits having been judged to be in no failure, and (h) a third container for containing therein integrated circuits having been judged to be in failure.
It is preferable that the controller updates the reference, based on spectrum of an integrated circuit having been judged to be in no failure.
In still another aspect of the present invention, there is provided a recording medium readable by a computer, storing a program therein for causing a computer to carry out the above-mentioned method.
There is further provided a recording medium readable by a computer, storing a program therein for causing a computer to act as the above-mentioned apparatus.
The advantages obtained by the aforementioned present invention will be described hereinbelow.
As mentioned earlier, a method of detecting an integrated circuit in failure, based on spectrum of a power source current is accompanied with a problem that it is quite difficult to prepare a reference, that is, spectrum of a power source current of an integrated circuit having no failures, because of difference in processing conditions in fabrication of integrated circuits. The inventor found out the fact that almost all integrated circuits actually have no failures among integrated circuits having been judged to have no failures in accordance with a conventional method, and that quite a small number of integrated circuits having failures could not be detected in accordance with a conventional method. Based on this discovery, the inventor herein suggests a method of detecting an integrated circuit in failure by analyzing spectrum of a power source current of all integrated circuits under test.
Specifically, integrated circuits are all tested in accordance with a conventional method to thereby have an under-test integrated circuit set containing integrated circuits having been judged to have no failures in accordance with a conventional method. This under-test integrated circuit set contains integrated circuits which have failures, but have not been detected in accordance with a conventional manner, at a quite small rate, though.
Then, power source current spectrum is observed for each one of integrated circuits belonging to the under-test integrated circuit set, to thereby calculate a mean value and standard deviation. Then, a gap between spectrum and the mean value in each one of the integrated circuits is standardized by the standard deviation to thereby quantify the gap in the under-test integrated circuit set.
Though spectrum of integrated circuits having no failures are expected to distribute in the vicinity of the mean value, spectrum of integrated circuits having failures distribute much far away from the mean value. Accordingly, it would be possible to select integrated circuits having no failures by removing integrated circuits having spectrum distributing far away from the mean value, even without preparation of a reference, that is, data about spectrum of integrated circuits having no failures.
The above and other objects and advantageous features of the present invention will be made apparent from the following description made with reference to the accompanying drawings, in which like reference characters designate the same or similar parts throughout the drawings. | {
"pile_set_name": "USPTO Backgrounds"
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Target games are old, particularly those involving a missile and a target. With the advent of materials in which there is provided a loop portion and a hooking portion such as that produced by the Velcro Corporation, toys and games have been produced utilizing the hook (male portion) and loop (female portion) materials in various ways. Velcro or materials like Velcro have been used in target games, such as those described in U.S. Pat. Nos. 3,032,345, issued to Lemelson, May 1, 1962 and 3,857,566, issued to Lemelson, et al., Dec. 31, 1974 and 3,917,271, issued to Lemelson, et al., Nov. 4, 1975, but all of the games produced according to the teachings of these patents have several disadvantages. In the first place, Velcro or its alternative is expensive and large quantities of it render the game inapplicable for certain uses. Another disadvantage is, that Velcro when used for the target makes it extremely difficult to print indicia on the target. Velcro is opaque and cannot be seen through, whereby it is imperative that printing on the face of the Velcro be clear and distinct to provide an easy target for the missile thrower. As hereinbefore mentioned, Velcro is extremely difficult to print on and as a matter of fact, the characters or indicia on the Velcro are very indistinct and fuzzy.
These and other difficulties are obviated by the use of the present invention. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to methods and computer-readable media to implement computation of the propagation velocity of seismic waves.
Knowledge of the propagation velocity of seismic waves is required to produce accurate images of underground geology to prospect for oil and gas with the reflection seismic method. The reflection seismic method deploys an array of sound sources (e.g., dynamite, air guns, and vibrating trucks) and receivers (e.g., seismometer or hydrophone) on or below earth's surface to construct an image of underground geology. To gather data to make the image, each sound source produces an explosion or vibration that generates seismic waves that propagate through earth, or initially through water then earth. Underground geologic interfaces, known as “reflectors,” will reflect some energy from the seismic waves back to the receivers. Each receiver will record a “trace” at that time. A multi-channel seismic recording system such as the StrataView manufactured by Geometrics Inc., San Jose, Calif. can be used to collect all of the recorded traces for a given shot. This collection is referred to as a “shot gather.”
To map the underground geology, the recorded time of the shot reflection events of each seismic trace will be mapped to the position at which the reflection occurred, using the propagation velocities of seismic waves, which vary with respect to spatial position. This mapping is known as “prestack depth migration.” Claerbout, Toward a unified theory of reflector mapping, Geophysics v. 36, p. 467 (1971), which is incorporated by reference herein, describes a method of computation known as “downward continuation,” which enables prestack migration. Downward continuation is a computation that mathematically moves the recorded seismic traces and simulated seismic source traces into the subsurface to achieve prestack depth migration.
Downward continuation requires an initial estimate of propagation velocity known as the “migration velocity.” These estimated propagation velocities can be obtained for instance by the method of stacking velocity analysis developed by Taner and Koehler, Velocity spectra—digital computer derivation applications of velocity functions, Geophysics 34, p. 859 (1969), which is incorporated by reference herein.
To form an image from the recorded data at a given depth, downward continuation migration computes the dot product of the downward continued recorded seismic trace and its corresponding downward continued source trace. When an energy peak on the recorded trace is time-coincident with an energy peak on the source trace an image can be formed. This method is known as the “zero time lag correlation imaging condition.” It is noted that the term “lag” is also referred to as “shift.” If the migration velocity matches the true propagation velocity, prestack migration will form an image of the reflector at the correct location. If the migration velocity differs from the true propagation velocity, prestack migration will form an image of the reflector at an incorrect location.
Sava and Fomel, Time-shift imaging condition in seismic migration, Geophysics, v. 71, p. 209 (2006), which is incorporated by reference, state that the zero time lag correlation imaging condition may be generalized to extract energy at a non-zero time lag and used to estimate the propagation velocities. When the migration velocity is incorrect, the energy peak on the downward continued source trace will not match the time of the energy peak on the downward continued recorded trace. By applying the correlation imaging condition at a number of time shifts, other than at zero lag, the amount of misfocusing in time can be computed and related to a velocity error. The generalized imaging condition is known as the “time-shift imaging condition.” For a given position on the recording surface and a given time shift, all the traces are summed. The collection of all these summed traces at that position for all the time shifts is known as “a time-shift gather.”
In regions with significant geologic complexity, velocity analysis using depth migration (MVA) is superior to methods which operate on prestack data. Migration in general, and depth migration in particular, simplify prestack data by correcting for the effects of offset, reflector dip, and propagation from source to receiver in a heterogeneous medium. When the migration velocity is incorrect, migration will incorrectly position the surface data in depth. Some MVA techniques attempt to flatten Kirchhoff common-offset depth migration gathers by measuring depth error as a function of offset and perturbing the migration velocity accordingly.
Kirchhoff offset gathers exhibit artifacts in complex examples, which are not seen in wave equation depth-migrated images, as described in Stolk and Symes, Kinematic artifacts in prestack depth migration, Geophysics v. 69, p. 562 (2004). Claerbout, Imaging the Earth's Interior (1985), which is incorporated by reference herein, devised the zero-time/zero-offset prestack imaging condition which forms the basis of most wave equation MVA techniques. Subsurface offset gathers can be converted to angle gathers by slant-stacking as described by Prucha et al, Angle-domain common image gathers by wave-equation migration, 69th Annual International Meeting, SEG, Expanded Abstracts, p. 824 (1999) and by Sava and Fomel, Angle-domain common-image gathers by wavefield continuation methods, Geophysics v. 68, p. 1065 (2003), and have been used for MVA, as described by Clapp, Incorporating geologic information into reflection tomography, Geophysics v. 69, p. 533, (2004) and by Sava, Migration and velocity analysis by wavefield extrapolation, Ph.D. thesis, Stanford University (2004). However, the slant stack may itself introduce spurious artifacts. Shen et al., Differential semblance velocity analysis by wave-equation migration, SEG Expanded Abstracts, p. 2132 (2003) describe a velocity update method which uses misfocusing in subsurface offset directly.
Another class of MVA methods uses the other wave equation prestack focusing criterion—misfocusing in time—to quantify velocity errors. As described by MacKay and Abma, Imaging and velocity estimation with depth-focusing analysis, Geophysics v. 57, p. 1608 (1992), which is incorporated by reference herein, time-shift gathers can be constructed by phase-shifting source and receiver wave fields in shot record migration. While time-shift gathers can be converted to angle gathers, as described by Sava and Fomel, Time-shift imaging condition in seismic migration, Geophysics, v. 71, p. 209 (2006), which is incorporated by reference herein, MacKay and Abma measured the depth corresponding to best focusing and invoked a relationship attributed to Faye and Jeannot, Prestack migration velocities from focusing analysis, SEG Expanded Abstracts, p. 438 (1986), which is incorporated by reference herein, to relate the measured depth error to a velocity perturbation. The technique has small reflector dip and small offset assumptions. Audebert and Diet, Migrated focus panels: Focusing analysis reconciled with prestack depth migration, SEG Expanded Abstracts, p. 961 (1992), which is incorporated by reference herein, outline an approach to partially overcome these limitations.
In the 1990's, one of the inventors, Dr. Higginbotham, developed a method of computing the propagation velocity of seismic waves in earth. The method assumed a migration velocity, generated time shift gathers using a shot record downward continuation depth migration and the time-shift imaging condition, and converted the time shift gathers to semblance gathers. The energy peaks on the semblance gathers corresponded to the amount of misfocusing in time. The magnitude of the misfocusing in time was used to update the migration velocity. The method incorrectly assumed that a time shift corresponded to zero offset travel time. The method computed inaccurate values of the propagation velocity of seismic waves in the presence of reflector dip and source-receiver offset, and it was not understood how to increase its accuracy. | {
"pile_set_name": "USPTO Backgrounds"
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A disk drive typically includes storage media, a read/write head and a head position encoder. The storage media is a platter that contains a large number of closely spaced concentric tracks. The head is positioned at a specific location over a track and instructed to read or write information on the media. In order to achieve high density storage, the tracks are located very close to one another and the placement of the head is very important. Head position encoders are known in the art and are roughly categorized into two types: electromechanical encoders and optical encoders. Electromechanical encoders generally sense current through magnetic coils to determine the head position. Optical encoders generally sense the application of light on a surface to determine the head position.
Known optical head position encoders are described in U.S. Pat. Nos. 4,703,176 and 5,084,791, incorporated herein by reference. The '176 patent describes a polyphase optical position encoder using a movable glass scale with alternating equally dimensioned opaque and translucent regions extending generally perpendicular to the locus of scale movement. A light source penetrates the scale and directs light onto a pair of photodetector areas symmetrically disposed about an axis of rotation of the disk drive head. The photodetectors are responsive to the light source and to the relative position of the scale. The photodetectors provide a quadrature-phase signal to a processor that is used to governs the movement of the head.
The '791 patent is similar to the '176 patent and includes a temperature detector. A processor is configured to determine the thermal expansion of the storage media based on a linear approximation and to adjust the head position based on the approximation of the thermal expansion. This technique is processor intensive and presumes that the thermal expansion is linear.
Accordingly, a limitation of existing disk drive head position encoders is that the temperature of the disk drive causes misalignment with the head and the recording tracks because of the thermal expansion of the storage media, and known compensation techniques for the expansion is performed by relatively complicated procedures of measuring the temperature and then estimating the position change. These compensation techniques also require additional hardware or firmware. Another limitation of existing disk drive head position encoders is that they determine position of the head based on a quadtrature-phase detection technique that does not provide a high degree accuracy.
What is needed is a disk drive head position encoder that is very accurate in position and that compensates for thermal expansion of the storage media in order to provide an accurate position of the head over the recording tracks of the storage media. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field
The present invention generally relates to the field of semiconductor processing. More particularly, the present invention relates to methods and apparatus for thermally processing a semiconductor substrate.
2. Description of the Related Art
During semiconductor processing, substrates may be heated to high temperatures so that various chemical and/or physical reactions can take place. Thermal processes are usually used to heat the substrates. A typical thermal process, such as annealing, requires providing a relatively large amount of thermal energy to the substrate in a short amount of time, and thereafter rapidly cooling the wafer to terminate the thermal process. Examples of thermal processes currently in use include Rapid Thermal Processing (RTP) and impulse (spike) annealing.
In general, these thermal processes heat the substrates under controlled conditions according to a predetermined thermal recipe. These thermal recipes fundamentally consist of a temperature that the semiconductor substrate must be heated to the rate of change of temperature, i.e., the temperature ramp-up and ramp-down rates and the time that the thermal processing system remains at a particular temperature.
Accurate temperature measurement is essential to control the process to achieve desired result and to maintain uniformity across the substrate during thermal processing. Temperature measurement of substrates being processed or chamber components is usually conducted in-situ by non-contact methods, such as using pyrometers to sense radiation energy from the target objects. A pyrometer generally detects energy level of a certain wavelength of radiant energy from the target objects to determine temperature of the target objects.
Accuracy of temperature measurement by pyrometers during thermal processing is usually affected by noises received in the radiant energy. For example, when measuring a temperature of a substrate being processed, radiant energy from the energy source may be directly or through reflection received by the sensor in addition to the radiant energy emitted by the substrate.
Various methods have been used to prevent unwanted radiant energy from entering a temperature sensor. For example, covers and shields are used to prevent background noises, such as radiation from the energy source, from entering the sensor. However, the covers and shields not only increase system complexity, reduce system flexibility, but also limit the lower range of the sensors.
Spectral filters are also used to filter out background radiant energy within a working wavelength of the radiant sensor. The working wavelength is generally within a limited range for measuring a semiconductor substrate during thermal processing. Suitable spectral filters, such as a spectral filter containing rare earth elements, are usually expensive. Additionally, spectral filters usually absorb radiant energy from the heating source within the working wavelength. The absorption not only amounts waste of the radiant energy from the heating source, but also causes overheat of the spectral filters themselves.
Therefore, there is a need for improved apparatus and methods for efficient and accurate temperature measurement during thermal processing. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to bellows-type expansion joints, and more particularly to reinforced expansion joints which are adapted to couple lengths of rigid conduit together while allowing relative movement to occur.
While various types of resilient expansion joints have been known for years, such joints generally take one of two forms. One form, which will be termed the shallow or flowing arch type, has generally evolved for use in smaller-diameter applications wherein a uniformly resilient joint may be provided. Examples of shallow-arch joints are shown in U.S. Pat. Nos. 3,359,014--Clements and 3,552,776--Leymann. Joints or couplings of this type have a gradually enlarged section intermediate their ends which acts as a bellows to enable axial contraction or elongation of the joint, and moreover to accommodate angular and transverse misalignment of the ends. The body or carcass of the joint is generally of uniform construction, that is, the cross-sectional buildup or formation of the carcass is consistent from one end to the other. Shallow-arch joints are conventionally manufactured by a molding process which effectively limits their size due to the bulk and expense of the necessary molds.
In forming the reinforcing layer of flowing-arch expansion joints it is conventional to use a fabric which has been cut on a bias so that the warp and/or weft of the fabric extends at some angle to the axis of the joint. As set forth in U.S. Pat. No. 3,359,014 the preferred angle for such bias-cut layers is generally 45.degree.. This provides both axial and radial support to the structure, yet allows the materials to be distorted sufficiently to be formed in the desired shape wherein the center of the material is distended to a larger diameter than the ends thereof, i.e. material is wrapped around a mandrel or mold core to form a bulged cylinder.
Owing to the deficiencies inherent in such a construction wherein flexure must take place over a large proportion of joint length, efforts have been made to add additional reinforcing structure. For instance, as in U.S. Pat. No. 3,359,014 a metal band may be placed about the joint at its center; or, as shown in U.S. Pat. No. 3,552,776 a reinforcing insert of metal or the like may be molded within the elastomeric body. While the shallow-arch type of expansion joint has the attributes of relatively low cost and weight in sizes up to approximately 20 inches in diameter, the relatively low strength factor and high tooling costs have prevented this design from becoming popular in large-diameter applications.
By far the most popular design of expansion joint for high pressure and/or high temperature applications is the so-called high arch design, as exemplified in U.S. Pat. Nos. 3,580,616 and 3,429,592--Merkwacz. The arch of this joint has substantially straight walls, and occupies only a relatively small, highly-defined portion of the total length of the joint. The walls of the arch are substantially perpendicular to the axis of the joint so as to form a sharp, narrow bellows in the joint. It has been found that the high arch joint lends itself to an extremely strong mode of construction, inasmuch as rigid reinforcing rings can be formed within the straight portions of the body or externally over the straight sections of the expansion joint on either side of the straight-walled arch. Although such reinforcement does not extend into the arch of the joint, due to the sizing and proportioning of the high, narrow arch a highly pressure-resistant joint can nonetheless be formed.
Although the so-called high arch expansion joint has been developed to a high degree, certain problems inhere in its construction and use. In order to achieve the required rigidity, the reinforcing rings in or over the body of the joint must be firmly and permanently located. Excess motion of the joint tends to break the internal rings free of the surrounding material, causing them to move or migrate within the carcass of the joint. Continued movement of this sort eventually results in destruction of surrounding material, and failure of the joint. As shown in U.S. Pat. No. 3,580,616 other methods of reinforcing the linear portions of the joint have been developed; generally, the approach is to surround as much of the joint as possible with an inextensible material which will prevent the joint from distending, and relegate any movement to the bellows or arch portion of the joint.
In order to overcome the inherent propensity of the high-arch joint to collect particulate material and sediment, a soft or sponge-like filler may be placed in the annular cavity formed by the arch. While this prevents the accumulation of particulate material it also inhibits movement of the joint, and commonly decreases the elongation, compression, and transverse distortion of the joint by 50%.
Attempts have been made to achieve the benefits of both types of joints in a single structure; for example, in U.S. Pat. Nos. 3,206,228 and 3,799,825 various types of supporting structures are shown which are intended to lend additional strength to expansion joints. U.S. Pat. No. 3,799,825 illustrates the prior art method of building up the carcass of an expansion joint wherein the fabric used to build up the carcass of the joint is cut on a bias such that the angle of the strands of the fabric is very high with respect to the axis of the joint. By using narrow lengths of material in which the strands run substantially crosswise, the strands are discontinuous and thus do not fully encircle the body of the joint. Since the strands only extend partway about the conduit a measure of expansion is possible through a stretching of the elastomer lying between adjacent sets of strands. As in the case of the above-described high-arch joint construction, reinforcement intermediate the arches can be provided by disposing helical metal ribbons upon the cylindrical walls of the assembly.
From the foregoing, it will be appreciated that it would be highly desirable to provide a large, high-pressure expansion joint which exhibits the strength of the high-arch expansion joint, but with the flexibility, low-weight and lack of particle entrapment which characterizes the flowing-arch style of joint.
It is therefore an object of the present invention to provide an expansion joint substantially as strong as conventional reinforced high-arch joints, without the presence of rigid rings imbedded therein or installed over the straight body sections.
Another object of the present invention is to provide an expansion joint which is substantially lighter than presently-available joints of equivalent pressure ratings.
Yet another object is to provide an expansion joint whose strength is comparable to a reinforced high-arch style of joint, but which does not entrap particulate material.
Yet another object is to provide an expansion joint of the low-arch configuration which will withstand internal pressures as well as a reinforced high-arch joint.
Yet another object is to provide a superior expansion joint which is substantially more economical to manufacture than prior-art joints of comparable pressure ratings.
Another object of the invention is to provide an expansion joint of the flowing arch configuration but which can be formed in large diameter sizes with or without the use of a mold.
Still another object is to provide a joint of the low-arch type which can be made in larger sizes than heretofore practical. | {
"pile_set_name": "USPTO Backgrounds"
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Existing OCR engines may suffer from low accuracy rates. For many applications where OCR may be highly desirable, the error rates of commonly available OCR engines may be unacceptably high, even for relatively simple documents. Additionally, when dealing with documents having complex layouts and contents, the best presently available OCR engines may still have a relatively low recognition rate. Therefore, an improved method of post processing OCR output data is desirable. Post-processing systems may be used to attempt to correct these errors improving the quality of the text.
Frequent OCR errors include too many erroneous characters within a word and word segmentation errors, but other errors, such as systematic mis-recognition of particular strings may exist as well.
One common post-processing method involves comparing the OCR data to a dictionary. The dictionary may contain commonly occurring character strings as terms in addition to words, depending on the application. Various methods may be used to determine appropriate corrections for OCR data not matching terms in the dictionary, but often more than one equivalent correction may exist for a given character string. Dictionary methods may also have particular difficulties dealing with numeric data, acronyms, and proper names.
Many existing post-processing systems assume machine recognized text to have a high recognition rate. For example, in most systems, a numeric string recognizer may be used such that numeric strings are simply bypassed without any further processing. However, in practice, not all numeric characters will be recognized correctly (e.g. “3000” may be recognized as “300o”). In such cases, it is desirable for a post-processing scheme needs to correctly recognize a string, such as “300o” as numeric and provide correction.
Similarly, acronyms in inaccurate OCR data may not be properly recognized as such by many post-processing systems. Further, errors occurring in a proper noun may be difficult to detect. In many post processing systems, only the morphology of acronyms and proper nouns is used to detect these character strings. For example, an acronym may be defined as “a string of three to six uppercase letters, bounded by non-uppercase letters.” This definition is often useful for acronyms, but it is generally too limited to detect proper nouns. A surname or given name, for example, frequently does not exist in a lexicon, but it is desirable for these names to be recognized as proper nouns.
Stochastic n-gram models have been proposed as powerful and flexible methods to parse the text. In “Adaptive Post-Processing of OCR Text via Knowledge Acquisition,” ACM 1991 Computer Science Conference, Liu et al. used a tri-gram method to detect possible error characters in a word. If OCR output data has a high accuracy level, this method is reasonably efficient, but the method is less efficient for less accurate data sets. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to an oscillator and a semiconductor device.
2. Description of the Related Art
In recent years, reduction in power consumption is required in products made with ecological sensitivity or electronic devices such as portable devices. With this, reduction in current consumption is required of each of the elements (an oscillator and a semiconductor device) which control these electronic devices. This requirement also needs reduction in power consumption in a system operation, and how small the current consumption in the standby state is made leads to product differentiation in the system. For this purpose, it is necessary to decrease waiting time for stabilization of oscillation of a system clock (oscillator), which becomes always necessary, as much as possible and to perform a constant process (count of a clock and the like) early, in the state transition to the normal operation state from the above described standby state. Attention is paid to a method for decreasing average current consumption by transition to the standby state.
Besides, Japanese Patent Application Laid-open No. 6-338751 discloses a crystal resonator which shortens rise time by decreasing overshoot of oscillation frequency at a time of rise of the oscillator. | {
"pile_set_name": "USPTO Backgrounds"
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Ballistic armor of the above type requires a design allowing the armor to have low weight and high ballistic protection. This consideration derives from the fact that the armor is normally to be carried either by a person, or by a vehicle to be protected.
The construction of ballistic armor using ceramic pellets in one of its layers is well known in the field. In most cases, the pellets are embedded in a layer or matrix of material which may be resin, rubber etc. Such armors prove to be very efficient and have high multi-hit capabilities due to the fact that impact of a projectile on one ceramic pellet, or several adjacent ceramic pellets does not essentially affect the pellets surrounding the impact area. This is contrary to monolithic armors in which impact on one spot reflects on the entire monolith.
U.S. Pat. No. 5,763,813 discloses multi-layered armor comprising an outer, impact-receiving layer produced as a panel consisting of a single internal layer of high density ceramic pellets retained in panel form by a solidified material, for deforming and shattering an impacting high-velocity, armor-piercing projectile; and an inner layer adjacent to said outer layer, comprising a tough woven textile material for causing an asymmetric deformation of the remaining fragments of said projectile and for absorbing the remaining kinetic energy from said fragments.
WO 00/47944 discloses a ballistic panel comprising a carrier member and a plurality of cylindrical bodies made of a high density material, the bodies being attached to the carrier member at one end thereof by an adhesive, wherein two neighboring bodies are in contact with one another along their generatrix, i.e. having their longitudinal axes parallel to one another, or wherein three neighboring bodies are attached to an intermediate filler body positioned therebetween.
US 20070034074 discloses a composite armor panel comprising a main layer of pellets in a binder matrix, and front and back layers bonded thereto by a method in which forming the main layer and bonding the front and back layers thereto are performed simultaneously. The method comprises providing the front and back layers, applying binder material to the pellets and the layers and heating the binder material to form the matrix and bind the front and back layers thereto. The method described in US 20070034074 comprises providing a mold of dimensions corresponding to those of the armor plate to be produced, disposing the mold horizontally, arranging the front layer in the interior of mold and along the side walls to form a cavity having sides and a bottom, filling the cavity with pellets in closely packed arrangement with their front ends facing said bottom, introducing in the mold the binder so as to fill all the spaces between the pellets and the bottom and sides of the cavity and to cover the pellets' rear ends, covering the rear ends of the pellets with the back layer, and applying heat to the mold and pressure to the back layer. Such method of production facilitates the application of pressure to the plate and ensures improved contact between the front ends of the pellets and the front layer, and the back ends of the pellets and the back layer, increasing confinement, due to which ballistic protection provided by the armor is improved. Furthermore, the use of ballistic fabric for the front and back layers allows for the binder material to be absorbed therein, which increases the ballistic protection capability of the armor plate. | {
"pile_set_name": "USPTO Backgrounds"
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Replenishing circuits may be used for this purpose, including means for evaluating the amount of oil in the pump and means for measuring and replenishing, bringing into play hydraulic and electro-hydraulic components such as pumps, valves and electric valves as well as measuring means such as flow-meters, level sensors or pressure sensors.
Such devices are complicated and their operation as well as their regulation can be difficult.
Until now, the prior art did not include a supply or pumping device of simple construction enabling the removal of an accurately measured amount of fluid from a receptacle, as a function of an amount of fluid lost by an hydraulic installation. | {
"pile_set_name": "USPTO Backgrounds"
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(a) Field of the Invention
This invention generally relates to a support device for holding and storing a bottle. More particularly, but not by way of limitation, to a support for holding a long-necked bottle by the neck at an angle from the horizontal.
(b) Discussion of Known Art
The need for a device that supports long-necked bottles, such as wine bottles, has been know for some time. It is particularly important to store wine bottles at an angle, with the neck pointed generally downward in order to allow the wine to wet the cork and thus keep the cork from drying out and losing its desirable properties. Various known approaches provide some sort of a support wall or panel that include an aperture that has been adapted for engaging the bottle's neck. A problem associated with many of these devices is that they are often designed for replacing wine bottle racks that support a significant number of bottles, and thus take up a large amount of space and require correspondingly large footing supports.
Another limitation of known devices has been that they offer very little flexibility in the number of bottles that are to be supported by the wine rack. Typically, wine racks are designed to support a large number of bottles or a single bottle. While a large capacity rack is capable of supporting a single bottle, it is desirable to have a wine bottle rack that is versatile in that it can be a rack for supporting a single bottle or a multiple bottle rack.
Still another desirable feature in a wine rack is that the device be easily collapsed, so as to allow low cost shipping.
Another desirable feature in a wine rack is that it should incorporate few, if any, moving parts while still maintaining the ability to support wine bottles.
Yet another desirable feature in a wine rack is that the wine rack be easily separated and assembled into its basic components, so that the device can be shipped in a compact container, and then quickly assembled by the end user. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to an apparatus (hereinafter referred to as “light emitting apparatus”) having an element where a luminescent material is interposed between a pair of electrodes (hereinafter referred to as “luminescent element”). In particular, the present invention relates to a light emitting apparatus (hereinafter referred to as “EL light emitting apparatus”) having a luminescent element (hereinafter referred to as “EL element”) which utilizes a luminescent material (hereinafter referred to as “EL material”) by which EL (electro luminescence) is obtained as the luminescent material. An organic EL display and an organic light emitting diode (OLED: organic light emitting diode) is contained in the light emitting apparatus according to the present invention.
Also, the EL material which can be used in the present invention includes all of the luminescent materials that emit a light (phosphorescence and/or fluorescence) through a singlet excitation, a triplet excitation or both excitations.
2. Description of the Related Art
The EL light emitting apparatus is so structured as to have an EL element with a structure where an EL material is interposed between an anode and a cathode. A voltage is applied between the anode and the cathode to allow a current to flow in the EL material, to thereby re-couple carriers and emit a light. In other words, the EL light emitting apparatus does not require a backlight used in a liquid crystal display device because the light emitting element per se has a light emitting capability. In addition, the EL light emitting apparatus is advantageous in that the apparatus is broad in an angle of visibility and light in weight.
A passive matrix (simple matrix) EL light emitting apparatus is structured in such a manner that a plurality of anodes which are arranged in the form of stripes (bands) in parallel with each other and a plurality of cathodes which are arranged in the form of stripes in parallel with each other are orthogonal to each other, and an EL material is interposed between the anode and the cathode at each of the cross portions. With this structure, a pixel which is at a cross point between a selected (voltage applied) anode and a selected cathode is lit. In other words, a voltage is applied between the anode and the cathode to allow a current to flow in the EL material, to thereby re-couple the carriers and emit a light. The above drive method is called “current drive”.
However, there is a voltage drop (also called “IR drop”) due to a wiring resistance as a phenomenon which is a problem on the EL light emitting apparatus of the current drive type. This is a phenomenon that a voltage drops more as a distance from the power supply becomes farther even if the same wiring is used. This problem is remarkable particularly in the case where the wiring length becomes long, and it is one of obstacles in enlarging a screen of the EL light emitting apparatus.
In particular, in the passive matrix EL light emitting apparatus, a transparent electrically conductive oxide film generally for a visible light is used as the anode, but the electrically conductive oxide film has a problem that the resistance is higher than a metal film, and, thus the conductive oxide film is liable to be influenced by the above-mentioned voltage drop.
There is a fear that the voltage drop caused by the wiring resistance and a signal delay remarkably damage the uniformity of an image quality, cause a residual image phenomenon and become an obstacle to the large screen. The above problems are remarkable particularly in a light emitting apparatus which is several tens inches in a diagonal line. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a novel electroluminescence (EL) device and more particularly to an organic EL device capable of emitting light in a region of bluish purple to green at a high luminance and in a stabilized manner. Moreover, the present invention relates to novel aromatic dimethylidyne compounds useful, for example, as emitting materials for an EL device, processes for efficiently preparing the above compounds, and an EL device using the above compound.
2. Description of the Related Arts
A device utilizing EL performance of an organic compound has been long studied in view of fluorescence of the organic compound. For example, W. Helfrish, Dresmer, Williams et al. succeeded in emission of blue light using anthracene crystal (J. Chem. Phys., 44, 2902 (1966)). Vincett, Barlow, et al. produced a light emitting device by a vapor deposition method, using a condensed polycyclic aromatic compound (Thin Solid Films, 94, 171 (1982)).
However, only a light emitting device low in luminance and luminous efficiency has been obtained.
It is reported that emission of blue light of 100 cd/m.sup.2 was obtained using tetraphenylbutadiene as a light emitting material (Japanese Patent Application Laid-Open No. 194393/1984). In practice, however, the efficiency is markedly low and is unsatisfactory.
It is reported that a green light emitting organic thin film EL device providing the maximum luminance of more than 1,000 cd/m.sup.2 and an efficiency of 1 lm/W was developed by laminating a diamine compound conveying a hole and a luminous aluminum chelate complex as a light emitting material (Appl. Phys. Lett., 51, 913 (1987)).
It is also reported that a distyrylbenzene compound well known as a laser dye exhibits high fluorescent properties in the region of blue to blue green, and a light emitting material using the distyrylbenzene compound in a single layer form emits EL light of about 80 cd/m.sup.2 (European Patent 0319881).
However, a light emitting material providing light other than green light (particularly blue-based light) in a luminance as high as more than 1,000 cd/m.sup.2 and with high efficiency has not been obtained.
In connection with the structure of the aforementioned organic EL device, those obtained by properly providing a hole injection layer or an electron injection layer in a basic structure having a positive electrode/light emitting layer/negative electrode, e.g., a structure of positive electrode/hole injection layer/light emitting layer/negative electrode, or a structure of positive electrode/hole injection layer/light emitting layer/electron injection layer/negative electrode are known. The hole injection layer functions to inject a hole into the light emitting layer from the positive electrode, and the electron injection layer, to inject an electron into the light emitting layer from the negative electrode. It is known that placing the hole injection layer between the light emitting layer and the positive electrode permits injection of more holes at a lower voltage, and that electrons injected from the negative electrode or the injection layer into the light emitting layer are accumulated at the light emitting layer side in an interface between the light emitting layer and the hole injection layer when the hole injection layer does not have electron transporting ability, increasing a luminous efficiency (Applied Physics Letters, Vol. 51, p. 913 (1987)).
As such organic EL devices, for example, (1) a laminate type EL device having a structure of positive electrode/hole injection layer/light emitting layer/negative electrode in which the light emitting layer is made of an aluminum complex of 8-hydroxyquinoline, and the hole injection layer, of a diamine compound (Appl. Phys. Lett., Vol. 51, p. 913 (1987)), (2) a laminate type EL device having a structure of positive electrode/hole injection zone/organic light emitting zone/negative electrode in which an aluminum complex of 8-hydroxyquinoline is used in preparation of the light emitting zone (Japanese Patent Application Laid-Open No. 194393/1984), and (3) an EL device having a structure of positive electrode/hole injection zone/light emitting zone/negative electrode in which the light emitting zone is made of a host material and a fluorescent material (European Patent Publication No. 281381) are known.
In the above EL devices (1) and (2), although light emission of high luminance is attained at a low voltage, it is necessary to control the temperature of a vapor deposition source not to be more than 300.degree. C. i.e., as low as nearly an evaporation temperature in vapor deposition, because an aluminum complex of 8-hydroxyquinoline when used as a light emitting material is readily decomposable at a temperature of more than about 300.degree. C. It is therefore difficult to control conditions for production of a device and, moreover, the vapor deposition speed is decreased. Thus the devices (1) and (2) inevitably suffer from a problem of a reduction in productivity of devices. Moreover the aluminum complex of 8-hydroxyquinoline can emit green light, but not blue light.
In the EL device (3), a compound capable of injecting a hole and a electron from the outside, preferably an aluminum complex of 8-hydroxyquinoline is used as a host material, and as a fluorescent material, a compound capable of emitting light in response to re-combination of a hole and an electron, such as a known fluorescent dye.
In this device, among an injection function (function to inject a hole from either a positive electrode or a hole injection layer and also to inject an electron either from an electrode or a negative electron injection layer, upon application of electric field), a transport function (function to transport a hole and an electron upon application of electric field), and a light emitting function (function to provide a field for re-combination of a positive hole and an electron, thereby producing light emission), the light emitting zone (light emitting layer) should have the injection function, the transport function, and part of the light emitting function fulfilled by the host material, while only part of the light emitting function is fulfilled by the fluorescent material. For this reason, the host material is doped with a very small amount (not more than 5 mol%) of the fluorescent material. An EL device of the above structure can emit light in the region of from green to red at a luminance as high as above 1,000 cd/m.sup.2 by application of a voltage of about 10 V.
In this EL device, however, the same problems as in the above EL devices (1) and (2) are encountered, because it usually uses 8-hydroxyquinoline-Al complex as a host material. Moreover, it is impossible to emit light of a short wavelength having a higher energy than the energy gap value of the 8-hydroxyquinone from a fluorescent material; emission of blue light cannot be obtained.
As described above, the above devices (1), (2) and (3) cannot provide blue light emission of high luminance in a stabilized manner and with high efficiency. However, they provide an epoch making technical advance by showing that a high luminous and high efficiency EL device can be realized by selecting a light emitting material with a structure of positive electrode/hole injection layer made of amino derivative/light emitting layer/negative electrode. In this selection of the light emitting material, the three functions of the above light emitting layer should be satisfied. Moreover it should be taken into consideration that a material with excellent film forming properties as a light emitting layer should be selected. Moreover the material selected should have excellent heat resistance properties and should avoid decomposition at the time of heating for vacuum deposition. It has been difficult to find a light emitting material to satisfy all the above requirements. Thus the present inventors made extensive investigations to develop a compound providing light emission in a region of bluish purple to green, particularly in a blue region at a high luminance and with high efficiency.
The present inventors made extensive investigations to attain the above objects. As a result, they have found that stilbene-based compounds having specified structures have an injection ability, a transporting ability and a light emitting ability essential for a light emitting layer, are excellent in heat resistance and thin film forming properties, are free from decomposition even if heated to a vacuum deposition temperature, can form a uniform and dense film having excellent thin film forming properties, and moreover are rarely subject to formation of pinholes at the time of formation of the opposite electrode (metal), and that if the above compounds are used as light emitting materials, an EL device can be obtained with high efficiency and moreover the EL device provides stable light emission of high luminance from bluish purple to green upon application of a low voltage. Based on the findings, these present invention has been accomplished. Furthermore, the EL device is of high efficiency in a practical luminous region (80 to 200 cd/m.sup.2). | {
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Storing and organizing footwear has traditionally presented a number of problems. Closet space is often used inefficiently and shoes tend to become strewn about the floor of the closet. Locating and picking up shoes is usually quite aggravating.
My U.S. Pat. No. 5,050,746 (hereinafter, Patent No. '746) addresses and overcomes a number of these problems. That patent relates to a rotary shoe rack wherein a number of shoe supporting shelves are mounted along a vertical shaft that is rotatably mounted in a closet or other storage space. Each shelf of that apparatus carries a heel elevating support that is engaged by the heels of the shoes stored on the shelf. The support specifically disclosed in Patent No. '746 comprises a ring that encircles the shaft. The ring is mounted on the shelf by a plurality of support posts that are attached to an inner portion of the shelf. As explained in the patent, by elevating a heel portion above the shelf platform, proper ventilation is maintained around the shoe so that mildew does not collect on the sole of the shoe. Moreover, elevating the heel increases the inner circumference of the arrangement of shoes and therefore permits a greater number of pairs to be accommodated on each shelf.
Although my previously disclosed heel elevating support works quite well, it exhibits several drawbacks. Most significantly, the support is not vertically adjustable. The heels of the stored shoes are raised to a fixed height above the shelf. The support cannot be adjusted relative to the shelf, in order to accommodate different shoe sizes, men's and women's shoes and varying numbers of shoes as desired. In some cases larger sized footwear does not fit properly on the shelf because the heel support is fixed too low and the shoes extend beyond the periphery of the shelf. Additionally, my previous design requires that a number of posts be interconnected between the shelf and the heelsupporting rail. Manufacturing and assembling the apparatus can be fairly time consuming and tedious. I have also determined that an aesthetically improved heel rail support would be desirable. | {
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This invention relates to circuits and more particularly to a system for establishing the input impedance of an amplifier in a stacked configuration.
Prior attempts to match the input impedance of an amplifier to the impedance associated with a load, such as a load resistor, include adding a resistor to the amplifier in either shunt or series configuration. A drawback to this approach is that it adds a 3 dB noise figure in the circuit. A further drawback to this approach is that it is difficult to always set the input impedance of the amplifier and the gain of amplifier independently of each other.
Prior attempts to stack a mixer and an amplifier so that they could share a bias current involved the use of a current source in the circuit. A drawback to this approach is that the voltage used to operate the transistor associated with the current source consumes a valuable portion (e.g., 1.0 to 1.5 volts) of the overall voltage headroom available in the circuit.
In accordance with the present invention, the disadvantages and problems associated with prior circuits have been substantially reduced or eliminated.
In one embodiment, a circuit for establishing the input impedance of an amplifier includes an amplifier, a circuit component, a first feedback resistor, and a second feedback resistor. The amplifier has an input impedance and is coupled to a load having a load impedance. The circuit component is coupled to the load and shares at least a portion of a bias current with the amplifier. The first feedback resistor is coupled to the amplifier and the load, and has a first impedance. The second feedback resistor is coupled to the amplifier and has a second impedance. The input impedance of the amplifier is established based at least in part upon the first impedance and the second impedance.
In another embodiment, a circuit for establishing a bias current includes a mixer, an amplifier, a bias resistor, a comparator, and a drive circuit. The mixer receives a drive voltage and at least a portion of a bias current. The amplifier is coupled to the mixer and receives at least a portion of the bias current. A bias resistor is coupled to the amplifier at a node and a bias voltage exists at the node. The comparator is coupled to the node and compares the bias voltage with a reference voltage. The comparator further generates an output signal based at least in part upon the comparison. The drive circuit generates the drive voltage in response to the output signal such that the bias voltage substantially equals the reference voltage thereby establishing the bias current. | {
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The invention relates to a ball screw nut that is provided for a ball screw drive and comprises a tubular sheet-metal part with a thread profile functioning as a load section for roller bodies.
As a ball screw drive, a rolling element, helical raceway drive is defined, which includes balls as the rolling elements. The rolling elements traverse a helical-shaped load section that is formed by profiled sections of nut and spindle of the ball screw drive. After completely traversing the load section, the balls are fed through a deflection section located in the nut back into the load section. Ball screw drives are distinguished by high efficiencies of typically greater than 80% and can convert both rotational motion into a translational motion and also a translational motion into a rotational motion. With regard to standardization, reference is made to DIN ISO 3408-1:2011-04 and also the older standard DIN 69 051 part 1.
A ball screw nut according to the prior art is known, for example, from DE 28 29 433 C2. This ball screw nut consists of an outer sleeve that can be made from plastic and an inner sleeve-like component. The sleeve-like component has a screw-shaped groove and is provided with a plurality of radial passage holes on which ball return elements are set. The sleeve-like component also has, on its outer side, a helical-shaped groove that has the same pitch as the groove on the inner side, so that the sleeve wall essentially has the same strength everywhere. The ball return element consists of a cylindrical projection and a curved plate that has a grooved surface that corresponds to the outer contour of the sleeve-like component.
Another ball screw nut is known from DE 30 32 955 C2. This ball screw nut is produced using a compression molding method and is comprised of two halves each of which are produced from a metal band. In one of the halves, a return recess is formed, that is, a deflection section that feeds the balls of the rolling-element, helical raceway drive back into the load section after exactly one revolution around the spindle.
Another ball screw drive that has a ball rolling spindle, and a spindle nut arranged on this spindle, that is, a ball screw nut, is known, for example, from DE 10 2004 040 362 A1. In this case, the ball rolling spindle and the spindle nut also define a ball channel for the endless circulating of the balls. The ball channel comprises a helical-shaped, wound load section and a load-free deflection section with ends contacting the load section. The deflection section here describes two legs arranged at angles to each other viewed in the axial direction. An angle that is measured on the spindle axis and reaches from one end up to the other end of the deflection section preferably equals 140 to 150 degrees according to DE 10 2004 040 362 A1.
From DE 10 2011 081 966 A1, a rolling-element helical raceway drive is known that comprises a thread part constructed as a composite part. Thread pitches are here produced from metal by shaping processes and encapsulated with tubular carrier parts made from plastic. The rolling-element helical-raceway drive should be suitable for use in an electromechanical braking force booster.
A thread nut of a maintenance-free thread drive with sliding surfaces is known, for example, from DE 100 28 968 A1. This thread nut is a sleeve-shaped sheet-metal part that is produced, for example, from steel, copper, brass, or aluminum. On the metallic material of the sleeve there is a sliding coating that can contain polytetrafluoroethylene. | {
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A wide variety of diseases and maladies can be treated by surgical intervention. Increasingly, however, less invasive procedures are sought to achieve similar objectives while reducing risks and recovery time associated with more traditional surgical approaches. For example, a variety of thoracic surgical procedures, such as treatment of aortic aneurysms and arterial stenosis, were traditionally performed via a gross thoracotomy. Less invasive procedures, such as balloon-expanded stents and PTCA, have been developed which avoid the need for a gross thoracotomy, requiring instead only a small incision to gain access to the thoracic cavity intravascularly or through an intercostal opening.
Cardiac arrhythmias present a significant health problem. Cardiac arrhythmias include ventricular tachycardias, supra ventricular tachycardias, and atrial fibrillation. Of these, atrial fibrillation is the most common cardiac arrhythmia. It has been estimated that over one million people in the United States alone suffer from atrial fibrillation. Incidence of atrial fibrillation is expected to increase over the next several decades as populations in the United States and Europe trend older because atrial fibrillation tends to become more common with increasing age.
Atrial fibrillation may be treated with medication intended to maintain normal sinus rhythm and/or decrease ventricular response rates. Not all atrial fibrillation may be successfully managed with medication, though. A surgical approach was developed to create an electrical maze in the atrium with the intention of preventing the atria from fibrillating. Known, appropriately, as the “maze” procedure, this technique involves making atrial incisions which interrupt pathways for reentry circuits which can cause atrial fibrillation and instead direct the cardiac electrical impulse through both atria before allowing the signal to activate the ventricles. As a result, virtually the entire atrial myocardium, with the exception of the atrial appendages and the pulmonary veins, can be electrically activated. The maze procedure is very effective in reducing or eliminating atrial fibrillation. Unfortunately, the procedure is difficult to perform and has traditionally required a gross thoracotomy and cardiopulmonary bypass to permit the surgeon appropriate access to the patient's heart.
Several less invasive techniques have been proposed for achieving a similar maze-like effect in the atrial myocardium without requiring direct surgical intervention. For example, U.S. Pat. No. 6,267,760 (Swanson) and U.S. Pat. No. 6,237,605 (Vaska et al.), both of which are incorporated entirely herein by reference, suggest RF ablation devices intended to ablate cardiac tissue and create atrial myocardial lesions to achieve much the same purpose as the surgical incisions of the standard maze procedure. U.S. Pat. No. 6,161,543 (Cox et al.), which is also incorporated entirely herein by reference, suggests that a cryogenic probe be employed to freeze tissue instead of using the RF ablation devices to heat tissue. Each of these approaches leaves something to be desired, however. | {
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Some systems include a shared or common power bus that provides power to one or more electrical devices. For example, a typical automobile has an automotive power net. A power source, such as an alternator or battery, outputs power to the automotive power net and an electrical device, such as an electronic control unit (ECU), receives power from the automotive power net to perform an operation.
Unfortunately, by the time the power reaches a device from a shared power bus, the power may not be of high quality and free from disturbances. That is, the harsh environmental conditions (e.g., electro-magnetic interference, noise, or other undesirable conductions) surrounding the shared power bus, as well as the constantly changing operational states of the different devices that are simultaneously supplied power from the shared power bus, may introduce disturbances onto the bus (e.g., over voltage or current conditions, under voltage or current conditions, load dumps, voltage ringing, voltage or current spikes, as well as large and small electrical transients) and diminish the quality of the power. To compensate for low quality power, some systems include additional, often expensive filter components or operate less efficiently, relying on techniques that require a constant increase in energy consumption. | {
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It is known to provide an image capture device at a vehicle for capturing images of the scene occurring exteriorly of the vehicle, such as forwardly or rearwardly or sidewardly of the vehicle. The captured images may be processed by a processing system and the system may control the headlamps of the vehicle or may provide an image display to the driver of the vehicle or may provide other information or signals, depending on the particular application of the imaging system. | {
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In general, electronic device technology is becoming increasingly sophisticated. New features and capabilities are being added to devices every day that enhance the performance of the devices. As a result of the incorporation of these new features and capabilities, the associated electrical power requirements are also advancing and becoming more and more sophisticated and rigorous. In order to meet the electrical power demands of these new devices, the technology and sophistication of the power sources that enable operation of these devices is also increasing.
Among these increasingly sophisticated devices are portable electronic medical devices. Portable medical devices such as external defibrillators, bone saws and drills must meet exacting performance criteria, particularly since these devices are used in medical procedures. In addition, because of federal regulatory requirements and conditions, these devices must generally meet a higher standard of reliable performance over long periods of time. The power sources that energize these portable medical devices are critical to their operation and, therefore, must also meet exacting criteria not only in electrical performance, but also in their construction.
Electrochemical cells that power such portable electronic devices are typically engineered to exacting specifications that provide proper amounts of power and ensure correct and safe device operation. In addition, these cells undergo extensive testing and validation procedures before they are approved and qualified to be included in a device. In many cases, electrochemical cells and modular batteries are designed to work with a specific make and model device. Therefore, it is important that these electrical power sources be manufactured to correct specifications and quality standards to ensure proper device operation.
However, the lucrative and growing electrochemical cell and battery markets have attracted an increasing number of vendors to (re)manufacture and sell counterfeit or sub-standard electrical power sources to unsuspecting customers. In many cases, these counterfeit power sources are made to look like genuine electrochemical cells and batteries. However, these counterfeit electrochemical cells are often not made to the exacting specifications and standards of genuine electrochemical cells. As a result, devices that are powered by such counterfeit electrical power sources may not operate correctly. In fact, a device that is being powered by a counterfeit cell or modular battery may overheat, malfunction, or even cease operation. Counterfeit batteries may not provide adequate safeguards to protect the occurrence of unsafe conditions such as overheating of the cell during the charging and discharge processes. In some instances, over heating of the cell may cause an explosion. Furthermore, additional problems may occur during the recharging of these substandard cells. In addition, these cells may not adequately perform to specification after charging or the cells may even fail during the charging process.
As a result of the emergence of counterfeit electrochemical cells, device manufacturers have developed portable devices with authentication technologies to ensure the correct match between a genuine cell and the device intended to be powered. Among these authentication technologies is the “Secure Hash Algorithm” or SHA-1. Devices that utilize the “Secure Hash Algorithm” technology are generally equipped with internal circuitry that enables the device to communicate with the modular battery that is intended to power the device.
Electronic devices equipped with this type of authentication, generally issue a challenge question such as an encrypted identification code. Once the identification code has been received by the modular battery, the modular battery then issues a reply response such as an encrypted code. If the reply issued by the modular battery matches that which is programmed into the device, the electrochemical cell or modular battery is considered to be genuine and the power source will continue to operate and power the host device as designed. However, if no reply or an incorrect reply is given by the modular battery, the power source is considered to be counterfeit or incorrect. The device, therefore, will not allow itself to be powered by the power source it has identified as being improper.
However, there are many existing devices that were not originally equipped with such power source authentication capabilities. Nevertheless, there is still a need to ensure proper power source use with these devices. Retro-fitting a prior device with authentication technology would require the incorporation of additional circuitry elements into the device. This option may not be possible due to electronic circuit or space constraints within the device. Furthermore, retro-fitting a power source authentication circuit within an existing device would also not be cost effective.
Therefore, there exists a need to provide existing devices with a means to authenticate the power source that is powering it. The present invention, therefore, provides various embodiments in which existing electronic devices, which are not equipped with authentication technology, such as SHA-1, with a means to verify or authenticate the electrochemical cell or modular battery intended to power the device. | {
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Outdoor cooking is among the favorite pastimes of many. As such, the methods and equipment for doing so are considerably diverse. Cookers vary greatly in size from small, portable or indoor units to large commercial units designed to feed hundreds. Cookers further vary in purpose; some are merely to grill the food while others add a means to smoke the foods to provide varying flavors. These cookers also diversify in the fuel source used to provide heat; natural or propane gas, charcoal, and wood are all types of combustible fuels used. These combustibles further vary in how the heat is applied to the food; some cookers place the fuels directly below the food while others offset the fuel source.
Since many larger outdoor cooker lids are typically made of a metal plate which necessarily results in a cooker lid with significant weight, multiple problems are created for cooker users. One such problem is that a heavy cooker lid can be difficult to open or a user may become fatigued with repeated opening and closing cycles. A second problem is that most outdoor cooker lids are typically incapable of remaining fixed in a partially open position. To combat this, a variety of propping or lid lift assisting devices have been designed.
One method used to assist cooker users in opening heavy cooker lids is the attachment of a large, heavy counterweight on top of or behind the cooker lid that applies a force onto the cooker lid, counteracting the weight of the cooker lid. The counterweight may be as simple as a large weight attached to the lid or may involve a weight attached to the lid via a cable pulley, such that the weight is pulled downward by gravity, which helps open the lid. This counterweight is necessarily heavy in order to have the desired effect of reducing the force necessary to open the lid. The use of a counterweight to ease the opening of a cooker lid however adds a significant amount of weight and rotational inertia to the outdoor cooker itself. For a cooker having a size of twenty-four inches by sixty inches, the counter weight required would be nearly one hundred twenty pounds; a weight that could make the cooker too heavy to easily manage, cause it to lean to one side, and may be considerably expensive with modern steel prices. Counterweights attached to a pulley may need further attention as the weight or cable can pose a dangerous system and the heavy weight would likely need to be removed or otherwise secured prior to travel. Of further issue is that outdoor cooker lids using a counterweight frequently must be opened to the full extent allowable if the cooker user is to have both hands free to use inside the cooker. An outdoor cooker using a counterweight will only remain in a fully closed or fully open position without further assistance from the cooker user or another propping device.
Another method used to assist a cooker user in opening a cooker lid is the use of a compression spring attached to the outdoor cooker body that applies an upward force onto a cooker lid, pivoting the cooker lid upward. This method of assisting a cooker user in opening a cooker lid suffers from the same problems as the other methods of assisting a cooker user in opening a cooker lid; most notably the inability of the cooker user to stop the lid at any intermediary position between fully open and closed without the use of at least one hand or a propping device.
Recognizing the benefits of keeping an outdoor cooker lid fixed in a partially open position, a variety of propping devices have arisen. One type of propping device, such as the device disclosed in U.S. Pat. No. 5,213,299, is used to keep an outdoor cooker lid partially open involves two prop members adjacent to one another that are capable of having a distance between two prop ends increased, and that distance is fixed by disallowing movement between the members. A second type of propping device, which is disclosed in U.S. Pat. No. 6,176,232, includes a member that is wedged in between the cooker lid and the cooker body whereby the height of the lid is adjusted by shifting the member's proximity to the pivot. Yet a third type of propping device, such as the device disclosed in U.S. Pat. No. 6,705,306, includes a prop attached to the cooker lid with slots designed to fit onto a stop connected to the cooker body where the height of the lid is adjustable by placing slots of various heights upon the member into the stop.
These propping devices all suffer from similar inferiorities. These propping devices obstruct access to the cooking surface by the user from either the front of the cooker or along the side of the cooker and all attach to the cooker in such a manner as to make them visually apparent, reducing the overall visual appeal of the cooker. These propping devices further require extra effort by the cooker user in order to stabilize them; some require tightening and loosening, some require sliding a mechanism back and forth, and yet others require the cooker user to fit a prop onto a stop before being able to allow the lid to remain at a fixed, partially open position.
Therefore, current outdoor cooker technology suffers from two general problems with cooker lid opening assistance and partially opened cooker lid designs. First, the heavy cooker lid weight requires a considerable lifting force to open the cooker lid. Second, all current methods of reducing the lifting force needed to open the cooker lid by a cooker user require the cooker user to either open the cooker lid completely or prop the cooker lid open at a partially open position with either a propping device or with one of their own hands. Opening the cooker lid fully when the cooker user only needs the cooker lid partially open to gain the desired access to the interior of the outdoor cooker reduces the heat within the cooker and requires more effort from a cooker user than would otherwise be needed, while having to manually maneuver a secondary device to prop open the cooker lid can be cumbersome and reduce access to the cooking surface by the cooker user. The final option available to the cooker user is to use a hand to hold the cooker lid partially open, which forces the cooker user to dedicate a hand to keep the cooker lid partially open, limiting what the cooker user can do under the cooker lid. This only further reduces the effectiveness with which the cooker user can operate the cooker.
A third issue in modern outdoor cooker technologies is blending maximum access by the cooker user to cooking surfaces, maximum efficiency of an outdoor cooker's fuel source, and ease of cleaning the cooker after use. While cooking, fats and other materials may accumulate in the bottom of an outdoor cooker which can result in flare-ups, reducing food quality and potentially injuring the user. However, accessing the bottom portions of an outdoor cooker for cleaning frequently entails either lifting the cooker racks out from the cooker body or maintaining a sufficient distance between the cooker racks and the cooker bottom to be able to clean underneath the cooker racks. Leaving room under the cooker racks is inefficient, as the room left could be filled with meat or other foodstuffs intended to be cooked. Since cooker racks that have been in use are typically warm during or for some time after use or have food upon them, removal of the cooker racks to clean fat while the outdoor cooker is in use or soon thereafter is difficult. One common way of gaining access to a cooker bottom is by a mechanism designed to lift a cooker rack out of the cooker during use. One example of this type of mechanism is disclosed in U.S. Pat. No. 4,462,306. The ‘306’ patent discloses an outdoor cooker that contains a vertical lifting device attached to a single cooker rack.
Cookers as currently used force a cooker user to choose from among many commercially available cookers with various, and often limited combinations of features. The present disclosure is directed to one or more of the problems set forth above. | {
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(1) Field of the Invention
The present invention relates generally to the field of boiler water level detectors and, more particularly to systems for the detection of electrical faults, as well as water versus steam detection, in boiler water level detectors.
(2) Description of Related Art
The control of water level in a steam boiler is extremely critical, in that if a fire tube is exposed, a boiler explosion could result. The rate of thermal conductance from a fire tube by water is many times greater than that of steam, thus if steam blankets the tube, there is insufficient heat conduction from the tube and the tube rapidly overheats. In order to avoid this potentially catastrophic occurrence, steam systems are required to provide redundant water level indicators for each boiler.
One common solution to the requirement for redundant water level indicators has for some time included two independent visual level indicators. Such visual level indicators require penetrations for top and bottom of the indicators and a sight glass in which the level of water is visually apparent. However, boilers typically operate at high temperatures and pressures, often at a normal operating pressure of 3,000 psi. This factor presents an engineering challenge to make the sight glasses robust in such a hostile environment. As a consequence, sight glasses often leak, and a small leak at such a high pressure can quickly develop into a serious problem.
In recognition of this problem, standards setting organizations, such as for example the ASME, have provided alternative standards for providing redundant level indications. For example, one such redundant visual indicator may be isolated and an electronic level indication used instead. Such electronic level indications must themselves be robust and ideally are redundant, typically parallel circuitry, and not scanned, polled or multiplexed systems, but fully independent systems. However, electronic level indicators present challenges in design all their own due to the high temperatures involved. A typical electrical-type level indicator uses a water column system with spaced-apart conductive electrodes (also referred to as probes), with the water column mounted directly to the side of the boiler. An electrical potential is impressed across each of the spaced-apart electrodes, and the current is measured. If water is present between the conductors, the low impedance of the water results in a relatively high measured current. Conversely, steam is much less conductive, and thus if steam is present between the conductors, the high impedance results in a relatively low measured current. Commonly the higher current is used to illuminate one color or type of lamp, and the lower current illuminates another color or type of lamp, thus presenting to an operator an easily visible level indication. Additional logic circuitry may provide steam over water error indication, high and low level trip points, alarms, pre-alarms, displays, relay closures, SSR conduction, and other indications.
Some such electrical level indicators use a low DC potential with an impressed square wave periodic signal impressed upon it. The DC potential may cause hydrolysis of the water, and can result in explosive concentrations of hydrogen and oxygen within the steam system or electroplating. Thus, there remains a need for an electronic level indication system for boilers that avoids the hydrolysis problem.
Further, standards setting organizations have mandated various self-diagnostic features, such as for example power supply monitoring, clock function monitoring, electrode short detection, open wiring detections, and water over steam detection. Many systems have been offered to serve these various functions, but there remains a need in the art to provide an integrated electronic system which can effectively detect a circuit short, a circuit open, and/or a water vs. steam condition, wherein the electronic system sensing circuit has no direct current component which may cause hydrolysis.
Martin el al., in U.S. Pat. No. 4,020,488, described an apparatus for indicating when the value of a parameter lies above or below a predetermined limit. The apparatus includes two or more sensors each arranged to provide a warning signal when the parameter lies beyond a respective specified value, the value for at least one of the sensors being equal to or beyond the predetermined limit; and logic means including a validation circuit connected to the two sensors and arranged to provide a xe2x80x9cparameter-beyond-limitxe2x80x9d signal. This signal may be used to operate an alarm and/or an emergency trip, only when both sensors provide a warning signal. Various forms of apparatus are described in which the parameter sensed is the level of water in various items of a steam plant as used in power stations to provide an indication of high and/or low water level.
Bartles, in U.S. Pat. No. 4,224,606, describes a fluid level control circuit with a safety test function for a boiler water level probe of a fail safe type. The control circuit is connected to a field effect transistor controlled amplifier having a well defined threshold of operation. A safety test switch is provided to pull the amplifier""s input down below the threshold point, but not to a shorted condition. By observing the output of the system, it is possible to determine whether the fluid level detector is properly installed, and whether the amplifier has had any type of unsafe operating failure.
Spencer, in U.S. Pat. No. 4,482,891, describes a robust electronic liquid level gauge apparatus, particularly suitable for use with boiler drum water column. The apparatus comprises simple probe sensors in the water column, differential amplifier sensors, detectors responsive only to the simultaneous presence of a minimum level signal and a certain frequency, and logic circuits continuously processing outputs from four detectors: its associated probe detector, the one below, and the two above.
Cosser, in U.S. Pat. No. 4,646,569, describes a fluid level measurement system for the measurement of a level of fluid in a vessel. The electrical impedance of a first conduction path between a central rod electrode and a surrounding cylindrical electrode and the electrical impedance of the second conduction path between the cylinder and the vessel are established. The first conduction path is restricted to be below the minimum fluid level by an insulating coating on the rod. The second conduction path varies with the fluid level. An output signal is extracted from the electrodes potentiometrically which is indicative of the fluid level. The signal may be linearized by application to a circuit having a matched non-linear transfer function. With this arrangement, a continuous output signal indicative of the fluid level is produced which is not subject to errors due to changes in fluid resistivity.
Colley et al., in U.S. Pat. No. 4,692,591, describe a controller for controlling an electrode boiler steam humidifier, of the type operable from a source of polyphase alternating current. A plurality of current loop transformers, coupled to the boiler electrodes, sense the individual currents drawn in each phase of the polyphase alternating current. A plurality of full-wave bridge rectifiers individually couple the secondaries of the current loop transformers to the input of a voltage amplifier such that the output of the amplifier is indicative of the highest of the currents sensed in each phase of the boiler electrode current. When the output of the voltage amplifier exceeds a predetermined threshold, a control effect is produced such that operation of the humidifier is controlled in accordance with the highest of the individual phase currents drawn through each of the boiler electrodes.
Similarly, Colley et al., in U.S. Pat. No. 4,792,660, describe a controller for controlling an electrode boiler steam humidifier. The controller includes a plurality of current loop transformers, coupled to the boiler electrodes, for sensing the current drawn by the electrode boiler. A current level detector provides a control voltage to a solenoid controlled valve, associated with the boiler, to drain a predetermined quantity of water from the boiler and thereby reduce the electrode current, when the electrode current exceeds a predetermined upper current limit. A resettable counter is provided for limiting the number of automatic attempts which can be made to reduce the electrode current. Normal periodic actuation of the humidistat resets the counter to avoid reaching the predetermined count through long-term acquisition of isolated over-current occurrences. During normal operation of the boiler, the time required for the electrode current to decrease between a pair of predetermined current levels is monitored and is compared against a known reference in order to provide a general indication of the condition of the boiler.
Jordan et al., in U.S. Pat. No. 5,519,639, describe a system for monitoring the water level of a pressure drum having a pressure column. The monitoring system comprises a plurality of electrodes communicating with the column for contacting water and steam within the column. Each electrode has its own location and produces a first output which corresponds to the presence of water or a second output which corresponds to the presence of steam. A discriminator is operatively connected to the electrodes and the discriminator has an analog-to-digital converter for receiving the output of each electrode and converting the output to a digital signal. The digital signal represents the water conductivity for each electrode. A central processor is connected to the discriminator for powering the discriminator as well as for receiving the digital signals in order to determine a slope degradation between the conductivity and the location of each electrode in the column. The central processor also determines an inflection point between the water and the steam in the column. An LED display is used to indicate which of the electrodes are located in water and which of the electrodes are located in steam.
Richards et al, in U.S. Pat. No. 5,565,851, describe a fluid level sensing system, particularly for sensing the water level in a steam generating boiler. The sensing system comprises a vessel connected to the boiler so as to contain water and steam at substantially the same level as in the boiler, a number of vertically spaced electrodes projecting into the vessel, and circuitry for measuring the electrical impedance sensed by each electrode. The circuitry, which can be multiplexed to each electrode in turn, includes a first comparator for producing an output when the sensed impedance lies between the normal maximum impedance of the water and the normal minimum impedance of the steam above the water, this output being demultiplexed to drive a vertical display to show the level of the steam/water interface. The circuitry additionally includes a second comparator for producing a further output when the sensed impedance lies below the normal minimum impedance of the water, which further output is indicative of a variety of different fault conditions and drives a fault indicator.
And finally, Richards, in U.S. Pat. No. 6,118,190, describes a circuit for controlling a fail-safe operation of measurement and control apparatus for detecting the presence or absence of water by making a measurement of the impedance experienced in a gap between an insulated tip of the electrode and a surface held at a reference voltage or else connected to ground. The apparatus may be configured to provide an alarm when water is present and should not be, or vice versa. The circuit comprises comparators, a phase detector, and a triple-redundant drive circuit which drives a relay. One comparator ensures that when operating with water as the normal condition, an electrode fault, such as could be caused by excessive contamination, will cause the system output to indicate an abnormal condition. Another comparator discriminates between the water condition and the steam condition. Yet another comparator ensures that there is no output if there exists an abnormal condition or any fault condition. It follows that there will only be an output if the sensor is in the normal condition. This is then shown to operate a relay using a secure triple redundancy drive circuit so that the relay contacts may be used to indicate a normal or an abnormal/fault condition.
However, the art does not describe a system which includes a dual frequency sensing signal which develops no direct current aspect, and which is used to indicate an open circuit condition, or short circuit condition on the same sense line, as well as boiler level measurements and a fault indicator, all within the same sensing circuit.
It is therefore an object of the present invention to sense for an open and/or a short circuit condition, as well as a water vs. steam condition with a single system. It is a further object of this invention to provide a method of sensing for an open and/or a short circuit condition, and a water vs. steam condition, with a single circuit. It is also an object of this invention to provide for sensing such conditions with a circuit with a net sum integral zero signal applied to the electrode probes to eliminate the possibility of hydrolysis within the boiler system.
The present invention addresses these and other needs in the art by providing a dual-frequency signal generator which develops two AC components with no associated DC component. The two frequencies are mixed and sent through an impedance matching circuit to match the impedance of the signal generating portion of the system with the impedance of the boiler water under measurement.
The impedance-matched signal is then directed to two legs, one leg directed through one of a plurality of electrode probes and then to a first filter circuit, and the other leg is directed a second set of filters. In combination, the filters pass either the higher or the lower of the two frequencies to determine an open or short condition in the level sensing circuitry, as well as a steam over water condition. | {
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This invention relates to mobile or portable cellular communication systems, and more particularly to a compact antenna apparatus for use with mobile or portable subscriber units.
Code division multiple access (CDMA) communication systems provide wireless communications between a base station and one or more mobile or portable subscriber units. The base station is typically a computer-controlled set of transceivers that are interconnected to a land-based public switched telephone network (PSTN). The base station further includes an antenna apparatus for sending forward link radio frequency signals to the mobile subscriber units and for receiving reverse link radio frequency signals transmitted from each mobile unit. Each mobile subscriber unit also contains an antenna apparatus for the reception of the forward link signals and for the transmission of the reverse link signals. A typical mobile subscriber unit is a digital cellular telephone handset or a personal computer coupled to a cellular modem. In such systems, multiple mobile subscriber units may transmit and receive signals on the same center frequency, but unique modulation codes distinguish the signals sent to or received from individual subscriber units.
In addition to CDMA, other wireless access techniques employed for communications between a base station and one or more portable or mobile units include those described by the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard and the industry-developed Bluetooth standard. All such wireless communications techniques require the use of an antenna at both the receiving and transmitting end. It is well-known by experts in the field that increasing the antenna gain in any wireless communication system has beneficial affects on wireless systems performance.
A common antenna for transmitting and receiving signals at a mobile subscriber unit is a monopole antenna (or any other antenna with an omnidirectional radiation pattern) A monopole consists of a single wire or antenna element that is coupled to a transceiver within the subscriber unit. Analog or digital information for transmission from the subscriber unit is input to the transceiver where it is modulated onto a carrier signal at a frequency using a modulation code (i.e., in a CDMA system) assigned to that subscriber unit. The modulated carrier signal is transmitted from the subscriber unit to the base station. Forward link signals received by the subscriber unit are demodulated by the transceiver and supplied to processing circuitry within the subscriber unit.
The signal transmittal from a monopole antenna is omnidirectional in nature. That is, the signal is sent with approximately the same signal strength in all directions in a generally horizontal plane. Reception of a signal with a monopole antenna element is likewise omnidirectional. A monopole antenna does not differentiate in its ability to detect a signal in one azimuth direction versus detection of the same or a different signal coming from another azimuth direction. Also, a monopole antenna does not produce significant radiation in the elevation direction. The antenna pattern is commonly referred to as a donut shape with the antenna element located at the center of the donut hole.
A second type of antenna that may be used by mobile subscriber units is described in U.S. Pat. No. 5,617,102. The directional antenna comprises two antenna elements mounted on the outer case of a laptop computer, for example. A phase shifter attached to each element imparts a phase angle delay to the input signal, thereby modifying the antenna pattern (which applies to both the receive and transmit modes) to provide a concentrated signal or beam in the selected direction. Concentrating the beam increases the antenna gain and directivity. The dual element antenna of the cited patent thereby directs the transmitted signal into predetermined sectors or directions to accommodate for changes in orientation of the subscriber unit relative to the base station, thereby minimizing signal loss due to the orientation change. In accordance with the antenna reciprocity theorem, the antenna receive characteristics are similarly effected by the use of the phase shifters.
CDMA cellular systems are interference limited systems. That is, as more mobile or portable subscriber units become active in a cell and in adjacent cells, frequency interference increases and thus bit error rates also increase. To maintain signal and system integrity in the face of increasing error rates, the system operator decreases the maximum data rate allowable for one or more users, or decreases the number of active subscriber units, which thereby clears the airwaves of potential interference. For instance, to increase the maximum available data rate by a factor of two, the number of active mobile subscriber units is halved. However, this technique cannot generally be employed to increase data rates due to the lack of service priority assignments to the subscribers. Finally, it is also possible to avert excessive interference by using directive antennas at both (or either) the base station and the portable units.
Typically, a directive antenna beam pattern is achieved through the use of a phased array antenna. The phased array antenna is electronically scanned or steered to the desired direction by controlling the phase angle of the input signal to each antenna element. However, phase array antennas suffer decreased efficiency and gain as the element spacing becomes electrically small when compared to the wavelength of the received or transmitted signal. When such an antenna is used in conjunction with a portable or mobile subscriber unit, generally the antenna array spacing is relatively small and thus antenna performance is correspondingly compromised.
In a communication system in which portable or mobile units communicate with a base station, such as a CDMA communication system, the portable or mobile unit is typically a hand-held device or a relatively small device, such as, for instance, the size of a laptop computer. In some embodiments, the antenna is inside or protrudes from the devices housing or enclosure. For example, cellular telephone hand sets utilize either an internal patch antenna or a protruding monopole or dipole antenna. A larger portable device, such as a laptop computer, may have the antenna or antenna array mounted in a separate enclosure or integrated into the laptop housing. A separately-enclosed antenna may be cumbersome for the user or manage as the communications device is carried from one location to another. While integrated antennas overcome this disadvantage, such antennas, except for a patch antenna, generally are in the form of protrusions from the communications device. These protrusions can be broken or damaged, as the device is moved from one location to another. Even minor damage to a protruding antenna can drastically alter its operating characteristics.
Problems of the Prior Art
Several considerations must be taken into account in integrating a wireless-network antenna into an enclosure, whether the enclosure comprises a unit separate from the communications device or the housing of the communications device itself. In designing the antenna and its associated enclosure, careful consideration must be given to the antenna electrical characteristics so that signals propagating over the wireless link satisfy predetermined system standards, such as, the bit error rate, signal-to-noise ratio or signal-to-noise-plus-interference ratio. The electrical properties of the antenna, as influenced by the antenna physical parameters, are discussed further herein below.
The antenna must also exhibit certain mechanical characteristics to satisfy user needs and meet the required electrical performance. The antenna length, or the length of each element of the antenna array, depends on the received and transmitted signal frequencies. If the antenna is configured as a monopole, the length is typically a quarter wavelength of the signal frequency. For operation at 800 MHz (one of the wireless frequency bands), a quarter-wavelength monopole is 3.7 inches long. The length of a half-wavelength dipole is 7.4 inches.
The antenna must further present an aesthetically pleasing appearance to the user. If the antenna is deployable from the communications device, sufficient volume within the communications device must be allocated to the stored antenna and peripheral components. But since the communications device is used in mobile or portable service, the device must remain relative small and light with a shape that allows it to be easily carried. The antenna deployment mechanism must be mechanically simple and reliable. For those antennas housed in the enclosure separate from the communications device, the connection mechanism between the antenna and the communications device must be reliable and simple.
Not only are the electrical, mechanical and aesthetic properties of the antenna important, but it must also overcome unique performance problems in the wireless environment. One such problem is called multipath fading. In multipath fading, a radio frequency signal transmitted from a sender (either a base station or mobile subscriber unit) may encounter interference in route to the intended receiver. The signal may, for example, be reflected from objects, such as buildings, thereby directing a reflected version of the original signal to the receiver. In such instances, two versions of the same radio frequency signal are received; the original version and a reflected version. Each received signal is at the same frequency, but the reflected signal may be out of phase with the original due to the reflection and consequence differential transmission path length to the receiver. As a result, the original and reflected signals may partially cancel each other out (destructive interference), resulting in fading or dropouts in the received signal.
Single element antennas are highly susceptible to multipath fading. A single element antenna cannot determine the direction from which a transmitted signal is sent and therefore cannot be tune to more accurately detect and received a transmitted signal. Its directional pattern is fixed by the physical structure of the antenna components. Only the antenna position and orientation can be changed in an effort to obviate the multipath fading effects.
The dual element antenna described in the aforementioned patent reference is also susceptible to multipath fading due to the symmetrical and opposing nature of the hemispherical lobes of the antenna pattern. Since the antenna pattern lobes are more or less symmetrical and opposite from one another, a signal reflected to the back side of the antenna may have the same received power as a signal received at the front. That is, if the transmitted signal reflects from an object beyond or behind the intended received and then reflects into the back side of the antenna, it will interfere with the signal received directly from the source, at points in space where the phase difference in the two signals creates destructive interference due to multipath fading.
Another problem present in cellular communication systems is inter-cell signal interference. Most cellular systems are divided into individual cells, with each cell having a base station located at its center. The placement of each base station is arranged such that neighboring base stations are located at approximately sixty degree intervals from each other. Each cell may be viewed as a six sided polygon with a base station at the center. The edges of each cell abut the neighboring cells and a group of cells form a honeycomb-like pattern. The distance from the edge of a cell to its base station is typically driven by the minimum power required to transmit an acceptable signal from a mobile subscriber unit located near the edge of the cell to that cell""s base station (i.e., the power required to transmit an acceptable signal a distance equal to the radius of one cell).
Intercell interference occurs when a mobile subscriber unit near the edge of one cell transmits a signal that crosses over the edge into a neighboring cell and interferes with communications taking place within the neighboring cell. Typically, signals in neighboring cells on the same or closely spaced frequencies cause intercell interference. The problem of intercell interference is compounded by the fact that subscriber units near the edges of a cell typically transmit at higher power levels so that the transmitted signals can be effectively received by the intended base station located at the cell center. Also, the signal from another mobile subscriber unit located beyond or behind the intended received may arrive at the base station at the same power level, representing additional interference.
The intercell interference problem is exacerbated in CDMA systems since the subscriber units in adjacent cells typically transmit on the same carrier or center frequency. For example, two subscriber units in adjacent cells operating at the same carrier frequency but transmitting to different base stations interfere with each other if both signals are received at one of the base stations. One signal appears as noise relative to the other. The degree of interference and the receiver""s ability to detect and demodulate the intended signal is also influenced by the power level at which the subscriber units are operating. If one of the subscriber units is situated at the edge of a cell, it transmits at a higher power level, relative to other units within its cell and the adjacent cell, to reach the intended base station. But, its signal is also received by the unintended base station, i.e., the base station in the adjacent cell. Depending on the relative power level of two same-carrier frequency signals received at the unintended base station, it may not be able to properly differentiate a signal transmitted from within its cell from the signal transmitted from the adjacent cell. A mechanism is required to reduce the subscriber units antenna""s apparent field of view, which can have a marked effect on the operation of the reverse link (subscriber to base) by reducing the number of interfering transmissions received at a base station. A similar improvement in the antenna pattern for the forward link, allows a reduction in the transmitted signal power to achieve a desired receive signal quality.
In summary, it is clear that in the wireless communications technology, it is of utmost importance to maximize antenna performance, while minimizing size and manufacturing complexity.
The present invention is a directional antenna having a number, N, of outlying monopole antenna elements. These monopole elements are formed as a first upper conductive segment on a portion of a dielectric substrate. The array also includes the same number, N, of image elements. The image elements are formed as a second set of lower conductive segments on the same substrate as the upper conductive segments. The image elements, generally having the same length and shape as the monopole elements, are connected to a ground reference potential. To complete the array, an active antenna element is also disposed on the same substrate, adjacent to at least one of the monopole elements. In a preferred embodiment, the active element is disposed in the center of the array.
The monopole elements are typically formed as elongated conductive sections on the dielectric substrate. The dielectric substrate itself may be formed as a first elongated section on which the conductive elements are disposed, and a second elongated section perpendicular to the first elongated section, forming an interconnecting arm between the first elongated section and the center active element. Likewise, the center active element may be formed as an elongated dielectric portion of the same substrate on which a conductive portion is disposed.
The image elements may be connected together electrically. In one embodiment, they are formed as a single conductive patch on the substrate.
In a preferred embodiment, the monopole antenna elements are electrically connected to act as passive elements; that is, only the single active center element is connected to radio transceiver equipment.
The passive monopole elements and corresponding image elements are selectively operable to in either a reflective or directive mode. In one configuration, each respective monopole element is connected to a corresponding one of the image elements through a coupling circuit. The coupling circuit may be as simple as a switch, providing a connected and unconnected selectable configuration.
However, in the preferred embodiment, the coupling circuit contains at least two impedances. In this configuration, a first impedance element is placed in series between the monopole element and the image element when the switch is in a first position, and a second impedance element is placed in series when the switch is in a second position.
The switches and impedances may typically be embodied as microelectronic components disposed on the same substrate as the antenna array elements. Signals supplied to the antenna array assembly may then control the switches for shorting or opening the connections between the upper portion and lower portion of each antenna element, to achieve either the directive or reflective operational state. | {
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1. Field
Embodiments of the present invention relate to a refrigerator having doors to open and close storage chambers provided in a main body.
2. Description of the Related Art
In general, refrigerators are apparatuses which are provided with components of a refrigerating cycle to store articles received therein in a frozen or refrigerated state using cool air generated by an evaporator of the refrigerating cycle.
A refrigerator includes a main body provided with storage chambers to store articles, such as food, and doors to open and close the storage chambers. Each door is installed such that one side end thereof is rotatably connected to one side of the main body and is rotated in the rightward and leftward directions to open and close each storage chamber.
Recently, among refrigerators, a refrigerator, in which an opening is provided on a door and a sub-door to open and close the opening is installed at the opening so as to allow articles within a storage chamber to be taken out of the storage chamber without opening the door, has been developed and placed on the market. | {
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Recently, a camera system has been proposed which provides for the creation of instant images on demand in a similar manner to an instant Polaroid™ camera. The system proposed includes means for insertion of a card to manipulate the printed image so as to produce interesting effects. | {
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The present invention relates to monoclonal antibodies and antigens, and to the use of such antibodies and antigens in the detection of the presence and concentration of certain specific microorganisms implicated in the etiology of human periodontal diseases. More specifically, the present invention relates to monoclonal antibodies specific to antigens from Actinobacillus actinomycetemcomitans. Actinobacillus actinomycetemcomitans is generally associated with juvenile periodontitis.
Clinical assays specific to such bacteria in gingival and subgingival dental plaque are useful in the diagnosis of periodontal disease, in evaluating the progress of periodontal therapy, and in determining the status of the patient at subsequent recall examinations. The standard bacteriological techniques presently used to identify such microorganisms are time consuming, expensive, and require a high level of expertise. Further, such tests frequently give results which are not as accurate or as sensitive as desired or required.
Recently, various efforts and proposals have been made to improve or replace standard bacteriological techniques by the utilization of immunodiagnostic assay techniques. Such immuno assay techniques are based upon the formation of a complex between the antigenic substance being assayed and an antibody or antibodies in which one or the other member of the complex is labeled. For example, labeling may be by means of a radioactive element, such as I.sup.125, (radioimmunoprecipitation assays); a material having fluorescent properties (immunofluorescence assays); enzyme-linked immunoabsorbant assays (ELISA) or (immunoperoxidase assays). The labeled member of the complex facilitates detection and/or qualitative analysis of the complexed labeled antigen or antibody from the uncomplexed antigen or antibody.
In typical competition utilizing immunoassay assay techniques, the antigenic substance in the sample of the fluid being tested competes with a known quantity of labeled antigen for a limited quantity of antibody binding sites. Thus, the amount of labeled antigen bound to the antibody is inversely proportional to the amount of antigen in the sample. In contrast, typical immunometric assays employ a labeled antibody. In such assay, he amount of labeled antibody associated with the complex is directly proportional to the amount of antigenic substance in the fluid sample.
Although immunodiagnostic techniques can be a substantial improvement over previously used bacteriological detection techniques, many further improvements remain to be made. For example, the immunodiagnostic techniques presently in use frequently produce variable results because relatively crude antigens and antibodies are employed. For example, three serotypes of Actinobacillus actinomycetemcomitans are known to exist in the oral cavity of man, yet one or more of the serotypes frequently goes undetected using present immunodiagnostic techniques. Similarly, there are at least three serologic variants of B. gingivalis in the oral cavity of man and they differ in virulence, hence the identification of the serologic variants of B. gingivalis by immunologic means can offer considerable advantages over other methods of detection and quantitations, however, present methods do not allow such distinction to be made. The immunodiagnostic techniques which are currently available for use in the determination of periodontal diseases generally lack accuracy, sensitivity and specificity.
Monoclonal antibodies may be defined as identical proteins produced by known techniques. The basic techniques for producing monoclonal antibodies were developed in the mid-1970's after Kohler and Milstein successfully fused spleen lymphocytes with malignant cells (myelomas) of bone marrow primary tumors [C. Milstein, Sci Am. 243(4): 66-74, (1980)]. Monoclonal antibodies recognize a single specific antigenic determinant (chemical structure). A given antigen may have several determinants. Thus, if monoclonal antibodies alone are utilized, immunodiagnostic tests may lack specificity because the same determinant may be found on different antigens or molecules, or false reading may be made because a single antigen may contain repeating determinants. Conventionally produced antigens typically have multiple determinants. Until the present invention, efforts to solve this problem have been made without a great deal of success. It is highly desirable that monoclonal antibodies be produced that not only have the ability to recognize a desired molecule or structure in a complex, but also have the ability not to recognize the same determinant in an unrelated or undesired complex. The present invention provide a specific antigen for microorganisms which are associated with periodontal diseases and to monoclonal antibodies that recognize only those antigens, and more particularly to monoclonal antibodies that recognize specific species, or strains, of such antigens. Thus the present invention provides a means of substantially improving the accuracy of various immuno-diagnostic assays. | {
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The present invention relates to dynamic random access memories (DRAMs), and in particular to refreshing techniques.
DRAM devices function by storing charge on a capacitor at each memory location. The capacitor loses the charge over time, and accordingly it needs to be recharged to its original level, whether a 1 or 0, periodically. This period is known as the refresh period, tREF. A typical tREF value is 64 ms. This recharging is termed refreshing, and is done by doing a row access for every row in the memory device. In newer DRAM designs, the rows and columns are broken into multiple banks to break down large DRAM arrays into smaller pieces.
The row access operation is performed in two steps. First, a row is opened, or turned on, in a "sense" operation, by turning on the sense amps. Next, the row is closed by doing a "precharge" operation, using a precharge equalization transistor. When a refresh is performed, there is no need to select a particular bit with a column address, and the data is not read.
As the storage capacity of memory devices increases and the number of banks per device increases, the issue rate of refresh commands sent to the memory device from the controller also increases and can introduce a refresh overhead that unacceptably impacts the performance of normal memory accesses.
To reduce refresh overhead, it is desirable to refresh more than one bank for each refresh command. This approach can be called multibank refresh. With a given refresh command, more than one bank could be either simultaneously or sequentially refreshed. From a performance standpoint, it is more desirable to refresh banks simultaneously, so that the time that bank resources are tied up is minimized.
Simultaneous multibank refresh, however, has the problem of current spikes. Each refresh operation for each bank requires a certain amount of supply current over time. At the onset of the operation, there is an initial spike of current. This spike is large because the row sensing circuits have been designed to access cell data as quickly as possible in order to minimize the latency to the first allowable page access to bits stored in the sense amps. This spike, characterized by rate of change in current, dl/dt, can cause noise problems in a DRAM, since current spikes can reduce the internal supply voltage and cause failure in circuits on the same die or on other devices that share the same supply voltage. With multiple banks simultaneously doing a row sense, the current spike effect can be additive, thus causing greater probability of circuit failure.
Typically, a refresh operation is done by periodically addressing every row with a controller. Thus, interspersed between normal memory access operations, refresh commands are sent in the form of a RAS control signal with a row address. In a prior RAMBUS memory system, these commands are sent in packets which are decoded in the memory chips themselves.
In addition to the normal refreshing interspersed with memory accesses, the memory may also be put into a sleep or stand-by mode. In this mode, it is not being accessed, and minimal power drain is desired. This is accomplished by simply refreshing the memory when needed, and otherwise not doing memory accesses. Memory chips typically have on-chip counters for sequencing through all the rows and banks in order to accomplish such a self-refresh. This allows the memory chips to refresh themselves, without requiring the controller to be turned on to provide it with the refresh addresses and commands.
Because self-refresh mode uses a clock or sequencer on the DRAM itself, a synchronization issue arises when the device comes out of self-refresh mode and the controller takes over memory accesses and controlling refresh. The typical way the synchronization is handled is for the microprocessor, upon powering up out of a self-refresh mode, to send a burst of refresh commands covering all the data locations in the memory chip. In this way, it is ensured that the timing of the last refresh of every memory location is known to the microprocessor.
To keep up with increasing microprocessor speeds, there has been pressure to increase the speed at which memory is accessed. One method for accomplishing this is to shape the current pulse provided by the sense amplifier driver in order to increase access speed. This is discussed, for example, in an article by H. Geib, W. Rabnd. Schmitt-Landsiedel, entitled "Block-Decoded Sense-Amplifier Driver for High-Speed Sensing in DRAM's", IEEE Journal of Solid-State Circuits, Vol. 23, No. 9, September 1992. As memories become larger, however, more locations need to be refreshed at any given time, and refreshing draws more power in a shorter time for the larger memories. Thus, current spikes can cause significant noise problems on the power line during a refresh operation. Accordingly, refresh protocols limit refreshing to one row at a time in order to control refreshing noise. | {
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1. Field of the Invention
The present invention is directed to a balun transformer for providing a single ended output signal from a pair of differential input signals, and more particularly to a transmission line balun implemented by a pair of inter-coupled transmission line signal couplers.
2. Description of the Related Art
As is well known, RF wireless circuits utilize balanced outputs of signals to minimize the effect of ground inductance and to improve common mode rejection. Such circuitry include mixers, modulators, IF strips and voltage controlled oscillators. These balanced outputs, moreover, consist of differential signals which must be combined to provide a single ended output signal. One known type of device for combining differential signals into a single ended output signal is referred to in the art as a "balun" (balanced input/unbalanced output). Typically, baluns are tightly coupled structures fabricated much like a conventional transformer utilizing discrete components; however, the turns are arranged physically to include the interwinding capacitances as components of the characteristic impedance of a transmission line. Such a technique can result in increasing the bandwidth of the device up into the megahertz frequency range. More Recently, baluns have been implemented using distributed components. When implemented with discrete components, they add excessive loss and increase the cost of fabrication. When implemented in distributed form they exhibit less loss, but at wireless frequencies require a relatively large amount of board space together with an inherent limitation of being narrow band devices. | {
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This invention relates generally to integrated photovoltaic roofing systems, and more specifically to methods and systems for roofing shingles having photovoltaic modules integrated into the shingle.
At least some known roofing systems with asphalt roofs mount directly on top of the existing shingles. Other known roofing systems replace the roofing tiles with an area that looks like a black or blue area covering a portion of the roof. Such products are often advertised as being photovoltaic cells “integrated” into a shingle roof but the photovoltaic cells are simply surrounded by standard asphalt roofing tiles. However, such roofing systems lack flexibility in design or construction methods to allow the various colors and shapes that are necessary to match the various product lines available in the asphalt roofing market to provide the aesthetic appeal needed for a residential rooftop photovoltaic solar system. | {
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Modern business practices often require that several persons meet on the telephone to engage in a conference call. The conference call has introduced certain applications and techniques that are superior to those found in a meeting with persons physically present in the same location. For example, a conference call attendee who is not participating at the moment may wish to mute their audio output and simply listen to the other conferencee. This allows the particular conferee to work on another project while still participating in the conference.
While the conference call has been substantially helpful in minimizing travel expenses and other costs associated with business over long distances, significant obstacles still remain in accomplishing many tasks with the same efficiency as one would in having a meeting with all persons in the same physical location. For example, while the ability to talk privately to a particular conferencee during a conference call can be provided by offline mechanisms such as text chat channels, this requires the coupling of ASCII entry and display capabilities with a voice terminal on both sides of the private conversation. | {
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Modern computing networks can include multiple computing devices that work together as a coherent group. For example, multiple computing devices can work together to provide a fault-tolerant service in the event that one of the computing devices has an error or otherwise becomes unavailable. One example is the use of replicated state machines to provide a fault-tolerant service. In this approach, multiple state machines in a cluster maintain replicated data shards to provide continuous service in the even that one or more of the state machines has an error or otherwise becomes unavailable. A computing node can include a switch (e.g., a router) or an end point (e.g., a host device, server, etc.).
A consensus algorithm, such as the Raft consensus algorithm, can be used to manage replicating data amongst the data shards stored by each computing node. A consensus algorithm involves multiple data shards communicating to agree on values to make a decision. For example, in the context of replicated state machines, each data shard in the cluster can maintain a log of commands that the state machine takes as input and the consensus algorithm can be used to replicate the log amongst the data shards in the cluster.
A consensus algorithm can require that one data shard from each cluster be designated as the leader of the cluster. The leader of the cluster can be in charge of organizing data replication across the data shards in the cluster. For example, using the raft algorithm, log entries can flow from the leader to the other data shards, thereby causing higher resource consumption by the computing node storing the leader. A computing node can store multiple data shard and each data shard can be a member of a different cluster. As a result, a computing node can store multiple shards that are designated as the leader of their respective cluster. This can result in higher resource consumption by the computing node and cause performance issues. | {
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A photosensitive glass undergoes change in those areas that are exposed to short wave radiations, such as ultraviolet light. As a result, the exposed areas are capable of changing color when heated. The process of coloration essentially involves producing metal particles in a glass by photoexcitation, followed by thermal treatment.
The phenomenon was initially observed by Dalton in copper-containing glasses as described in U.S. Pat. Nos. 2,326,012 and 2,422,472. Armistead observed the phenomenon in silver-containing glasses as reported in U.S. Pat. No. 2,515,936, and Stookey observed it in gold-containing glasses as reported in U.S. Pat. No. 2,515,937. In the case of metallic silver, the colors observed were predominantly yellow or brown.
It has been conventional wisdom that the presence of boric oxide (B.sub.2 O.sub.3) in a glass composition tends to weaken photosensitivity. It followed, therefore, that B.sub.2 O.sub.3 should be avoided, or at least minimized, in photosensitive glasses. The Armistead patent indicates that up to 10 wt. % B.sub.2 O.sub.3 can be tolerated under certain conditions, but the oxide does not appear in any of the exemplary compositions in the patent. Subsequent patents, including later filed U.S. Pat. Nos. 2,515,943 (Stookey), usually restrict B.sub.2 O.sub.3 to not more than 5%. Consequently, photosensitive glasses have had alkali silicate compositions, that is, they have been composed essentially of alkali metal oxides, divalent metal oxides and silica. In contrast, silver halide photochromic glasses are all based on borosilicate base compositions.
It has long been known that a more varied combination of physical properties can be achieved in borosilicate glasses than can be readily obtained in glasses based on silica alone as the glass former. For example, laboratory ware is usually produced from a borosilicate glass rather than from less expensive lime glasses. This is because the borosilicate is equally easy to melt, has better chemical durability and provides a lower coefficient of thermal expansion.
The restrictions imposed on boric oxide content in the patents cited above, therefore, significantly diminishes the flexibility of the glass chemist in designing photosensitive glasses. This is particularly true of glasses having the physical properties desired for special applications. Accordingly, it would be desirable to have photosensitive glasses available with relatively large B.sub.2 O.sub.3 contents. | {
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Known is a method of fabricating a semiconductor device by connecting the electrodes of a semiconductor chip to the leads connected to the external terminals by wire bonding, this method is applied regardless of package form. Also known is a method of fabricating a semiconductor device by use of a lead frame. The following outlines this later method.
As is well known, a semiconductor chip formed with an integrated circuit is mounted on the island of a lead frame with an adhesive, for example. Plural electrode pads on the semiconductor chip are connected to corresponding leads with metal fine wires (or wire). Then, the semiconductor chip and the surroundings thereof are integrally molded for resin encapsulation with a resin such as a synthetic resin. The leads of the outer side of resultant resin-molded package are ultimately separated from the lead frame, and appropriately bent and cut, if necessary. Thus, a semiconductor device can be fabricated.
To attach the metal line wires bonds between the plural electrode pads on the semiconductor chip mounted on the island and the surface of the corresponding leads, a metal line wiring apparatus known as a wire bonder must be programmed to recognize the electrode pads and the corresponding leads. To do so, the edge of each lead must be captured as an optical image to store the contour of the lead in the memory of the wire bonder.
In recognizing the leads of a semiconductor device lead frame, the wire bonder makes use of the external view of each lead as a reference. Therefore, a lead having a defect such as torsion, luster, or rough surface causes a wide variation in the recognition accuracy of the wire bonder.
Recently, the increasing number of pins on one semiconductor device inevitably increases the number of leads thereof and the miniaturization of semiconductor devices accordingly decreases the width of each lead and the interval between leads (or the lead pitch). Currently, a typical lead width is as small as 0.07 mm and a typical lead pitch is 0.16 mm. Consequently, as the lead width and the lead pitch narrow, it is more difficult, when connecting the plural electrode pads arranged on a semiconductor chip to the corresponding leads with metal line wires, for the metal line wire to be connected to the lead at the center along the width of the lead.
Such being the case, attaching the metal line wire to the lead off-center of the width or, detachment of the metal line wire from the lead causes a connection failure. Therefore, no matter how small the lead gets, the center of each lead is must be accurately recognized. Conventionally, however, if the lead has inadequate flatness or distortion, the center of each lead cannot be optically recognized with a high degree of precision.
It is therefore an object of the present invention to provide a semiconductor substrate, a lead frame, a semiconductor device, a method of fabricating the same, a circuit board, and an electronic apparatus that facilitate the optical recognition to prevent poor wire bonding. | {
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The ease and efficiency of modern day air travel has shrunk the geography of the world and people are able to travel from one place to another around the world traveling longer distances than before. As a result, air travel for many involves spending longer durations on board depending upon the distance between the departure and destination points. In order to keep passengers entertained, modern day aircrafts come equipped with entertainment programs such as music, games and videos, which are typically pre-stored and are displayed to the passengers on a display screen based on their choice and selection. These display screens may be rectangular shaped screens provided on the rear side of each cabin seat, viewable by the passenger sitting behind and facing the front portion of display screen. Some aircrafts are equipped with display screens which provide passengers moving maps showing views of the aircraft's transit path and other transit related information such as flight symbols, departure and destination marker beacons, track line i.e., path of journey from departure point to destination point, and names of cities etc. nearer to the present position of flight along with pointers. Display of such information is enabled by a system which typically utilizes the present location of the aircraft and, based on other information collected from the navigation system and global positioning receiver of the aircraft, shows moving maps providing visual representation of one or more transit related information. Generally, the moving maps show the above details in two dimensional view on the display screen with some information being presented in a three dimensional view.
During flight transit, the moving map as shown on the display screen re-orients itself based on the location of the flight and the information displayed on the screen is continuously updated to show the present location, altitude, ground speed, true airspeed, weather information etc., which keeps the passengers updated on the transit and location information of the aircraft. In long haul flights or in travel over cities with historical importance, passengers may desire seeing and learning about various historic places/monuments, either natural or man-made, which are present between the proposed departure and destination points. Such offer of knowledge on the historic places of interest provides a new kind of knowledge oriented entertainment which may be of interest to several passengers on board. For example, a person taking a flight from United States of America to Paris, there can many points of interest such as Statue of Liberty, Eiffel tower, etc. which a passenger would like to see and learn about.
However, due to the altitude of flight, and climatic conditions, it is not possible to view in real time such points of interest. There may be systems provided in aircraft display screens that allow the user to view some static images of a monument as an aircraft crosses it during its flight path; however, the view is static and does not enhance the visual or learning experience for the passenger. There is also no audio program associated with a certain point of interest that would provide information on that particular point of interest so as to educate the passenger on the historical/architectural/geographical importance of the monument/point of interest.
Accordingly, in order to provide the passengers an enhanced entertainment option and to enrich their visual experience on the points of interest encountered in the aircraft's flight path, there exists a need for technology which enables the passengers to visualize a point of interest as a three-dimensional model which provides one or more different types of views on moving maps to further enhance the visual experience of the passenger.
There also exists a need for technology which enables the passengers to learn about a specific point of interest while viewing it on the display screen by providing the option of an audio program audio program associated with a certain point of interest that would provide historical/architectural/geographical information on that particular point of interest. | {
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1. Field of the Invention
The invention relates to analog-to-digital converters and, more particularly, to meters employing analog-to-digital converters for a plurality of alternating current power lines. The invention also relates to a method of analog-to-digital conversion and, more particularly, to such a method that synchronizes serially communicated output digital values from analog-to-digital conversions.
2. Background Information
Whenever there are serial streams of data for a plurality of different channels, synchronization of the data is an issue. A typical mechanism for resolving this issue is to employ dedicated hardware to provide a suitable synchronization signal. For example, if the starting point of a clock associated with one set of serial data for the different channels of an analog-to-digital (A/D) converter is known, then the dedicated hardware can be employed to assure synchronization (and, thus, provide a subsequent starting point) for a subsequent second set of data for those different channels. However, in the absence of such a synchronization signal, another mechanism is required.
It is known to provide an A/D converter having a plurality of input analog channels and a single addressable digital output.
Channel synchronization can apply to any count of plural channels. For example, FIG. 1 shows, for six channels, the relative timing of serial data including a serial enable (SE) input signal 2, a serial data output frame sync (SDOFS) output signal 4, and a serial data output (SDO) signal 6 from a six-channel, serial output A/D converter (not shown) for two successive sets 8,10 of six samples. Serial data is normally read from the A/D converter with simultaneously sampled channels appearing in consecutive order (i.e., samples 12,14,16,18,20,22 of the first set 8; samples 24,26,28,30,32,34 of the second set 10). This process is continuous until the sampling system of the A/D converter is reset or loses power.
Alternatively, some A/D converters output one SDOFS output signal for only the first of six samples.
However, other than the initial synchronization of the six channels via the SE input signal 2, there is no physical mechanism to verify that the sampled six channels are in the correct order (e.g., the correct samples 12,14,16,18,20,22 of one set, such as 8, versus, for example, samples 16,18,20,22 of one set, such as 8, erroneously combined with samples 24,26 of a subsequent set, such as 10) in the SDO signal 6. For example, if noise or another malfunction results in extra or missing SDOFS output signal(s) 4, then the hardware (not shown) downstream of the A/D converter (not shown) has no mechanism to detect this error. Hence, it is believed that only some hypothetical interpretation of the data (i.e., the samples 12,14,16,18,20,22 and/or the samples 24,26,28,30,32,34) from the SDO signal 6 might reveal whether the channel data is in the appropriate order for each of the sets 8,10 of samples.
There is room for improvement in analog-to-digital converters, meters employing analog-to-digital converters and methods of analog-to-digital conversion. | {
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With the rapid rise in demand for communication of large amounts of data to and from mobile communication devices, traditional mobile voice communication networks are evolving into networks that communicate with Internet Protocol (IP) data packets. Such IP data packet communication can provide users of mobile communication devices with voice over IP, multimedia, multicast and on-demand communication services.
An exemplary network structure for which standardization is currently taking place is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN). The E-UTRAN system can provide high data throughput in order to realize the above-noted voice over IP and multimedia services. The E-UTRAN system's standardization work is currently being performed by the 3GPP standards organization. Accordingly, changes to the current body of 3GPP standard are currently being submitted and considered to evolve and finalize the 3GPP standard. | {
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Methods for preparing samples for analysis generally rely on dangerous chemical reagents, hazardous conditions, and long preparation times. The United States Pharmacopoeia (USP) method for TiO2 determination requires digesting a sample with boiling H2SO4 for 8 hours with subsequent filtration of the solution. This procedure is dangerous, lengthy and not sufficiently accurate because a filtration step is involved. While a cosmetic formulation containing TiO2 could be treated in a microwave with a mixture of nitric acid and HF to produce a clear solution suitable for Ti determination by AA, HF is a very strong health hazard, and during digestion high pressures, for example up to 450 psi, may develop. Thus, in addition to being hazardous to use, the accuracy of these methods and time they take to complete make them less than desirable. | {
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Device manufacturing has become exceedingly complicated over time. Because of the operation of certain devices, stringent tests must be passed in order for the devices to be approved for consumer use. The integration of certain device components has made such tests tedious, leaving limited options for streamlining the testing process. In some cases, components responsible for wireless communication must be tested to ensure their ability to accurately send and receive data. In these cases, a client device and a reader device are often tested using methods that can be time consuming, thereby causing delays in the manufacture and release of products. In the case of NFC devices, when the client device must be tested with multiple different reader devices, delays are exacerbated by certain measures required to sequentially maneuver the client device proximate to multiple different reader devices. | {
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1. Field of the Disclosure
The present disclosure relates to guides used to hold food pans in place for prep tables used in the food service industry. More particularly, the present disclosure relates to a guide having multiple discrete levels at which to place the food pans.
2. Description of the Related Art
In the food service industry, prep tables are used in kitchens to help cooks or other personnel to prepare dishes. The tables will typically comprise a refrigerated compartment, and an open table top. One or more food pans are placed in the open table top, and hold one or more food items. The food in the pans is kept at a food safe temperature by the refrigerated compartment below them.
In currently available systems, there is no way for users of these prep tables to adjust for ambient conditions, which can vary significantly. The height of the pans may need to be changed to lower them deeper into the table top, or elevate them closer to the surface. In current designs, the guides holding the pans must be removed and reattached to allow for different heights, or multiple pan guides must be purchased for each level desired. Changing pan guides can be very difficult and time-consuming, and buying several different guides can be costly. Accordingly, there is a need for a device that alleviates these problems. | {
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Wagering on sporting events, such as horse races, for example, is a large and growing industry in many parts of the world. Various types of betting products or systems are available for various types of sporting events For example, typical horse racing bets allow bettors to bet on the finishing position of a single horse or several horses in a particular race or series of races. For instance, a bettor can bet on a particular horse to finish first (win), finish in the top two (place), or finish in the top three (show). A bettor may also make various combination bets with multiple horses, such as an exacta bet (covering the top two finishing horses in order) or a trifecta bet (covering the top three finishing horses in order). In addition, a bettor may bet on a series of races, such as the daily double (winners of two consecutive races), the pick-three (winners of three consecutive races), and the pick-six (winners of six consecutive races), for example.
In a pari-mutuel betting system, all bets regarding a particular event are aggregated, a commission (or “take-out”) is taken by the track, and the remainder is distributed among the winning bettors. For example, pari-mutuel betting systems are commonly used in North America (and other various places throughout the world) for betting on horse races. | {
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Field of the Invention
The present invention relates to a technique for recognizing a plurality of types of input operations.
Description of the Related Art
In recent years, there have been widely used touch input apparatuses that recognize a touch operation based on X and Y coordinate values of a position at which an input unit such as a touch panel is touched by an operation object such as a user's finger or a stylus, and perform various kinds of processing according to the touch operation. Generally, the touch input apparatuses recognize the touch operation based on whether information such as the touched position, and a movement distance, a movement speed, and an input time of the touched position satisfies a predetermined condition. Japanese Patent Application Laid-Open No. 2011-134212 discusses a method in which a “move” (an operation of moving the operation object while keeping the operation object in contact with the input unit) is determined to have been input if the variance value of a touch position is larger than a predetermined value.
Further, there have been also emerging apparatuses that are operable based on X and Y coordinate values of the operation object being in a proximity state with respect to the input unit. The proximity state is a state where the operation object is slightly away from the input unit and is also referred to as a hover state. Japanese Patent Application Laid-Open No. 2012-247960 discusses that a touch operation which is identified based on position information of the operation object being in the proximity state before touching the input unit is performed at the time when the operation object has touched the input unit.
Recognizing the operation based on only the information of the operation object being in contact with the input unit, as discussed in Japanese Patent Application Laid-Open No. 2011-134212, or only the information of the operation object being in the proximity state, as discussed in Japanese Patent Application Laid-Open No. 2012-247960, raises a problem that such recognition is easily affected by detection accuracy of a sensor or an unintended movement of a user. For example, a small vibration of the operation object may be detected at the moment when the user has touched the input unit even though the user has no intention to move the operation object and as a result, the operation according to the movement of the operation object may be incorrectly recognized. | {
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Brief Description of the Prior Art
Many restraining devices have previously been contrived for keeping infants seated upright in a high chair or other seat. The propensity of infants to wiggle in their chairs and slide down until they fall out of the chair is well known. A restraining device capable of preventing such sliding out of the chair will, of course, generally be required to have a portion of the restraint device extended through the crotch of the infant and around the waist.
Many devices have undertaken to safely and inexpensively achieve the objective of preventing the infant from sliding out of the high chair or other seat. Thus, for example, in U.S. Pat. No. 4,235,474, a harness for restraining a baby in a chair is illustrated. This harness has a body section which includes a crotch portion which extends around the buttocks of the baby and up across the abdomen. At a location near the upper end of the crotch portion where the crotch portion crosses the abodomen, the restraint device includes a pair of straps or wing portions which can be extended around the rear side of the seat and there tied together to lock the restraint device to the seat or chair, thereby preventing the infant from sliding out of the chair. The harness shown in this patent further includes a pocket which extends upwardly from the restraint device along the back of the infant, and is dimensioned to fit over the upper portion of the back of the chair. This type of harness allegedly does not restrain or impair the movement of the child's arms and legs, and the back of the infant is supported by the portion of the harness which extends from the crotch portion upwardly to the pocket which is slipped over the top of the chair.
A support harness is also illustrated and described in U.S. Pat. No. 4,050,737. In this support harness, a pair of shoulder straps are provided which extend over the infant's shoulders and are secured by Velcro straps to a tongue which projects upwardly along the back of the infant from a crotch portion which is centrally located in the fabric panel of which the harness is formed. The crotch portion carries a pair of opposed wings which include belts which can be extended around the back of the chair to secure the support harness to the chair.
In U.S. Pat. No. 4,037,764, a child carrier is disclosed by which a child may be suspended from straps which can then be carried by a parent or placed over a supporting member located above the child's head. The child carrier device shown in this patent includes a large panel which includes a portion which extends upwardly across the buttocks of the child and is engaged by large flat wings extend from an abdomen portion of the panel around the sides of the child and engage Velcro strips or other fastening elements on the rear side of the buttocks portion of the panel. There then extends upwardly from the abdomen portion of the child carrier, a pair of elongated straps which form large bights or loops located above the head of the child, by which the child can be carried when seated in the carrier.
In U.S. Pat. No. 4,676,554, an article for restraining and supporting persons in a chair is illustrated and described. The restraining article includes a heart-shaped seat portion which carries a pair of straps at two of its corners. These straps can be used to tie the seat portion to the rungs at the corners of the seat of a chair in which the device is to be used. A pair of elongated straps extend from the point of the heart-shape of the seat portion, and when the seat portion or crotch portion of this device is pulled upwardly across the genital area and to the location of the abdomen, these straps can then be extended around the sides of the body and around the rungs or back of the chair, and there tied or secured to afford the desired restraint of the body of a person sitting on the crotch portion of the article. In this device, the back of the infant or other person restrained is pulled against the rungs or structural members of the back of the chair, and thus the article is not comfortable to the person restrained.
Other devices which may be employed for restraining infants or others when they are seated in a chair are those devices which are shown in Stauffacher at al U.S. Pat. No. 2,404,108 and Johnston U.S. Pat. No. 1,376,625. | {
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In the exploration of oil, gas and geothermal energy, drilling operations are used to create boreholes, or wells, in the earth. Drilling rigs used in subterranean exploration must be transported to the locations where drilling activity is to be commenced. These locations are often remotely located in rough terrain. The transportation of such rigs on state highways requires compliance with highway safety laws and clearance underneath bridges or inside tunnels. Once transported to the desired location, large rig components must each be moved from a transport trailer into engagement with the other components located on the drilling pad.
Moving a full-size rig requires disassembly and reassembly of the substructure and mast. Safety is of paramount importance. Speed of disassembly and reassembly is also critical to profitability. Complete disassembly leads to errors and delay in reassembly. When the substructure is assembled over the drilling pad, the mast is connected to the drill floor above the substructure. Each substructure side box is pin connected to its respective substructure base box. The drill floor center section is connected between the driller's side box and the off-driller's side box. The lower section of the mast is pin connected to the drill floor. The center mast section is pin connected to the lower mast section and the upper mast section is connected to the center mast section.
When the mast sections are connected together, the mast is raised by pivoting it on the pin connection to the drill floor. It is critical that the driller's side boxes remain secured to the base boxes during mast raising. Failing to properly secure them together results in their separation and collapse of the mast with significant damage to the entire structure and risk of injury or death to personnel. Once the mast has been raised over the drill floor, the side boxes are unpinned to disconnect then from the base boxes. Only then can the substructure can be raised.
It is desirable to have a connection system that is automated, to reduce rig-up and rig-down time. It is desirable to have a system that can be manually unlatched, and that automatically resets itself upon substructure raising. It is also desirable to have a system that latches automatically to speed the operation and to prevent accidents when an employee forgets to pin the side box to the base box. It is also desirable that the connection and disconnections be performed without the need to align the dog-ears (pin holes) for insertion of a pin.
More particularly, it is desirable to provide a substructure lock mechanism that cannot be left open when the side box is away. It is also desirable to provide a substructure lock mechanism that will automatically reset itself in a fairly short distance of raising the side box above the base box, such that if necessary to bring the side box back down for any reason during raising, the lock mechanism will re-engage.
The preferred embodiments of the present invention provide a unique solution to the engineering constraints and challenges of providing a rapid, safe, and reliable connection between the drill floor and substructure of a drilling rig. | {
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There is an increased interest in the application of control to combustion. An objective is to optimize combustor operation, monitor the process and avoid instabilities of the flame and their severe consequences. An objective is to improve the system performance, for example, by reducing the levels of harmful emissions, and to extend the stability domain by reducing oscillations induced by coupling between resonance modes and combustion. Correspondingly, monitoring of the flame by means of sensors in addition to the monitoring of the combustion products and their composition is becoming increasingly important.
The corresponding flame detection or flame scanning devices should be as reliable as possible, should allow the determination of as many as possible parameters of the flame, should be as broadly applicable as possible, and should be resistant to typical temperatures around the flames. All these requirements in principle might be met by using standard techniques. However, the problem arises that the more technically sophisticated the method of detection, and the more reliable the chosen technology, the more expensive the device becomes. Correspondingly, therefore, there is a demand for simple but nevertheless very sensitive, broadly applicable and reliable devices at low cost.
A flame scanner or flame detectors may be passive devices which record light emissions within the combustion chamber, such as IR emission of particulates following the Planck law for a given temperature, emission of different molecular species which are present during the heat release process like OH*, CH*, C2*, etc.
Other devices record the presence of molecules in IR by applying absorption spectroscopy. Such devices need a light source, a dispersive element, and an IR detector. These devices are active since they need a light source.
The main flame scanners give the flame on/off-status or eventually the frequency of the flame fluctuation.
More advanced sensors may give the following information:
flame parameter detection like λ or φ (air/fuel or fuel/air ratio); OH/CH, CH/CN, OH/C2, C2/CH ratios give information about the temperature or stochiometry;
temperature via measurement with 2- or 3-colors pyrometry, via measurement with H2O & CO(CO2) absorption in the MIR and NIR (tuneable lasers) range;
imaging: CMOS, CCD camera multi-bands detection, flame on/off-detection;
UV and IR measurements (UV, OH, CH, C2 chemiluminescence; VIS/IR Planck radiation of soot particulates);
UV/IR detection and heat release fluctuation thresholds method (high or low frequency changes).
Corresponding devices which can be used industrially are known.
For example, EP 0 616 200 discloses a device in which a camera that photographs the flame includes a plurality of photosensors which are integrated into the camera and are disposed on an imaging face thereof. The camera provides a flame image which can be displayed, and the corresponding images are analyzed for the derivation of combustion properties of the flame. The photosensors constitute a photosensor group in which each of the photosensors has a detection wavelength range, and the group of sensors covers the full contiguous visible radiation range. The photosensor values are used for the detection of radicals such as, for example, CH, OH and the like, the chemiluminescence of which can be detected in the visible range. An objective behind the device is to have a combined camera/spectrum detection device, wherein the former allows flame shape detection and the like, and the latter covers detection of the full visible wavelength range.
U.S. Pat. No. 6,045,353 discloses an a device for controlling the combustion of a burner. The device includes means for viewing the radiation emitted by the flame for collecting frame radiation intensity data as a function of time. The radiation is transported to an optical processor in which specific spectral regions of radiation are converted into electrical signals, which are then processed by a signal processor for integrating flame radiation intensity for the specific spectral regions of a period of time. The output of the signal processor is subsequently used to control the oxidant flow, fuel flow or both. Specifically, the device is located in the refractory block of the burner.
U.S. Pat. No. 6,318,891 discloses a device for determining the adiabatic temperature of a flame. The device comprises a sensor fiber which is coupled into a spectrograph. In the spectrograph, an adjustable section of the spectrum is acquired with a high resolution for individual radicals. The spectrograph thus includes a dispersive element, and the selected ranges are subsequently used in combination with theoretically calculated emission spectra for the determination of the Boltzmann temperature, which is then correlated with the adiabatic temperature of the flame.
WO 2006/091617 discloses a device for monitoring the flame across a contiguous spectrum by means of a plurality of discrete ranges measured by photodiodes. A beam splitter, which in this case is a dispersive element, is used for directing the collected light onto each of a multitude of photodiodes which cover the contiguous spectrum. The corresponding spectral range which is fully covered extends from 300 nm-1100 nm, | {
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U.S. Patent Application Publication No. 2011/0290674 of Shanley, IV, whose contents are incorporated herein in their entirety by this reference, discloses innovative apparatus and methods for heating selected areas of materials to forming temperatures while not forming other areas of the materials (i.e. “selective” thermoforming). As noted in the Shanley, IV application, one of many benefits of this selective thermoforming is that “unformed portions of the material remain substantially undistorted and thus may contain undistorted printing, art work, or other text, symbols, or information without concern as to whether intelligibility of the information will be degraded during the forming process.” See Shanley, IV, p. 1, ¶ 0006. Such benefits are difficult to achieve, however, as multiple issues may disrupt the consistency of the thermoforming process.
The apparatus and methods of the Shanley, IV application resolve many of these issues and function well for their intended purposes. Enhancements nevertheless may be desirable in order to improve the apparatus and methods and the products created thereby. At least some of these enhancements advantageously could avoid premature physical contact between polymeric material and a corresponding mold surface, reducing the ability of the mold surface to function as an undesired heat sink by drawing heat from the polymeric material.
Also as noted in the Shanley, IV application, plastic display holders for coins or souvenirs are among products producible using selective thermoforming techniques. Thermoformed cavities into which coins or souvenirs are inserted for display beneficially may be resized or reshaped (or both) for improved presentation of the objects. Yet additionally, the plates, or heat sinks, of the Shanley, IV application may be modified for improved operation. | {
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The two most basic electronic circuits within a fiber optic transceiver are the laser driver circuit, which accepts high speed digital data and electrically drives an LED or laser diode to create equivalent optical pulses, and the receiver circuit which takes relatively small signals from an optical detector and amplifies and limits them to create a uniform amplitude digital electronic output. In addition to, and sometimes in conjunction with these basic functions, there are a number of other tasks that must be handled by the transceiver circuitry as well as a number of tasks that may optionally be handled by the transceiver circuit to improve its functionality. These tasks include, but are not necessarily limited to, the following:
Setup functions. These generally relate to the required adjustments made on a part-to-part basis in the factory to allow for variations in component characteristics such as laser diode threshold current.
Identification. This refers to general purpose memory, typically EEPROM (electrically erasable and programmable read only memory) or other nonvolatile memory. The memory is preferably accessible using a serial communication bus in accordance with an industry standard. The memory is used to store various information identifying the transceiver type, capability, serial number, and compatibility with various standards. While not standard, it would be desirable to further store in this memory additional information, such as sub-component revisions and factory test data.
Eye safety and general fault detection. These functions are used to identify abnormal and potentially unsafe operating parameters and to report these to the user and/or perform laser shutdown, as appropriate.
In addition, it would be desirable in many transceivers for the control circuitry to perform some or all of the following additional functions:
Temperature compensation functions. For example, compensating for known temperature variations in key laser characteristics such as slope efficiency.
Monitoring functions. Monitoring various parameters related to the transceiver operating characteristics and environment. Examples of parameters that it would be desirable to monitor include laser bias current, laser output power, received power level, supply voltage and temperature. Ideally, these parameters should be monitored and reported to, or made available to, a host device and thus to the user of the transceiver.
Power on time. It would be desirable for the transceiver's control circuitry to keep track of the total number of hours the transceiver has been in the power on state, and to report or make this time value available to a host device.
Margining. “Margining” is a mechanism that allows the end user to test the transceiver's performance at a known deviation from ideal operating conditions, generally by scaling the control signals used to drive the transceiver's active components.
Other digital signals. It would be desirable to enable a host device to be able to configure the transceiver so as to make it compatible with various requirements for the polarity and output types of digital inputs and outputs. For instance, digital inputs are used for transmitter disable and rate selection functions while digital outputs are used to indicate transmitter fault and loss of signal conditions.
Few if any of these additional functions are implemented in most transceivers, in part because of the cost of doing so. Some of these functions have been implemented using discrete circuitry, for example using a general purpose EEPROM for identification purposes, by inclusion of some functions within the laser driver or receiver circuitry (for example some degree of temperature compensation in a laser driver circuit) or with the use of a commercial micro-controller integrated circuit. However, to date there have not been any transceivers that provide a uniform device architecture that will support all of these functions, as well as additional functions not listed here, in a cost effective manner.
It is the purpose of the present invention to provide a general and flexible integrated circuit that accomplishes all (or any subset) of the above functionality using a straightforward memory mapped architecture and a simple serial communication mechanism.
FIG. 1 shows a schematic representation of the essential features of a typical prior-art fiber optic transceiver. The main circuit 1 contains at a minimum transmit and receiver circuit paths and power supply voltage 19 and ground connections 18. The receiver circuit typically consists of a Receiver Optical Subassembly (ROSA) 2 which contains a mechanical fiber receptacle as well as a photodiode and pre-amplifier (preamp) circuit. The ROSA is in turn connected to a post-amplifier (postamp) integrated circuit 4, the function of which is to generate a fixed output swing digital signal which is connected to outside circuitry via the RX+ and RX− pins 17. The postamp circuit also often provides a digital output signal known as Signal Detect or Loss of Signal indicating the presence or absence of suitably strong optical input. The Signal Detect output is provided as an output on pin 18. The transmit circuit will typically consist of a Transmitter Optical Subassembly (TOSA), 3 and a laser driver integrated circuit 5. The TOSA contains a mechanical fiber receptacle as well as a laser diode or LED. The laser driver circuit will typically provide AC drive and DC bias current to the laser. The signal inputs for the AC driver are obtained from the TX+ and TX− pins 12. Typically, the laser driver circuitry will require individual factory setup of certain parameters such as the bias current (or output power) level and AC modulation drive to the laser. Typically this is accomplished by adjusting variable resistors or placing factory selected resistors 7, 9 (i.e., having factory selected resistance values). Additionally, temperature compensation of the bias current and modulation is often required. This function can be integrated in the laser driver integrated circuit or accomplished through the use of external temperature sensitive elements such as thermistors 6, 8.
In addition to the most basic functions described above, some transceiver platform standards involve additional functionality. Examples of this are the external TX disable 13 and TX fault 14 pins described in the GBIC standard. In the GBIC standard, the external TX disable pin allows the transmitter to be shut off by the host device, while the TX fault pin is an indicator to the host device of some fault condition existing in the laser or associated laser driver circuit. In addition to this basic description, the GBIC standard includes a series of timing diagrams describing how these controls function and interact with each other to implement reset operations and other actions. Some of this functionality is aimed at preventing non-eyesafe emission levels when a fault conditions exists in the laser circuit. These functions may be integrated into the laser driver circuit itself or in an optional additional integrated circuit 11. Finally, the GBIC standard also requires the EEPROM 10 to store standardized serial ID information that can be read out via a serial interface (defined as using the serial interface of the ATMEL AT24C01A family of EEPROM products) consisting of a clock 15 and data 16 line.
Similar principles clearly apply to fiber optic transmitters or receivers that only implement half of the full transceiver functions.
In addition, optical energy emitted from fiber optic transceivers is potentially dangerous to the human eye. Of particular concern are lasers, because they emit monochromatic, coherent, and highly collimated light that concentrates energy into a narrow beam. It is the energy density of this narrow beam that can harm biological tissues, particularly the eye.
The severity of harm to biological tissues depends on the amount of energy, the exposure time, and the wavelength of the light, where the eye is more sensitive to lower wavelengths. Furthermore, seeing that most light used in fiber-optic systems is infrared energy that cannot be seen, a victim might be exposed to such infrared energy without noticing it.
Therefore, to address eye-safety concerns, laser-based products are regulated by standards. In the United States, responsibility for these regulations resides in the Center for Devices and Radiological Health (CDRH) of the Food and Drug Administration. Outside of the United States, the principle regulation is International Electrotechnical Commission (IEC) Publication 825. These regulations cover both the devices themselves and products using them.
The CDRH and IEC regulations define four classes of devices as follows:
Class I: These devices are considered inherently safe. The IEC requires a classification label, but the CDRH does not.
Class II: Class 2 lasers have levels similar to a Class I device for an exposure of 0.25 second. Eye protection is normally provided by what is called a “normal aversion response.” This means that a victim usually responds to an exposure by an involuntary blink of the eye.
Class III: Both the CDRH and IEC define two subclasses: IIIa and IIIb. Class IIIa devices cannot injure a person's eye under normal conditions of bright light. They can, however, injure eyes when viewed through an optical aid such as a microscope or telescope. For Class IIIa, the CDRH concerns only visible light, while the IEC includes all wavelengths. Class IIIb devices can injure the eye if the light is viewed directly.
Class IV: These devices are more powerful than even Class IIIb lasers. They can injure the eye even when viewed indirectly.
The abovementioned regulations use equations to determine acceptable power levels at a given wavelength as well as procedures for making measurements or estimating power levels. Most lasers in fiber optics are either Class I or Class IIIb devices. Class I devices require no special precautions. Class IIIb devices, besides cautionary labels and warnings in the documentation, require that circuits be designed to lessen the likelihood of accidental exposure. For example, a safety interlock is provided so that the laser will not operate if exposure is possible.
One safety system is called open fiber control (OFC), which shuts down the laser if the circuit between the transmitter and receiver is open. A typical OFC system continuously monitors an optical link to ensure that the link is operating correctly by having the receiving circuit provide feedback to the transmitting circuit. If the receiving circuit does not receive data, the transmitting circuit stops operating the laser, under the assumption that a fault has occurred that might allow exposure to dangerous optical levels. This system, however, requires additional sensors and/or circuitry between the transmitter and the receiver. This is both costly and ineffective where the transmitter has not yet been coupled to a receiver.
In light of the above it is highly desirable to provide a system and method for identifying abnormal and potentially unsafe operating parameters of the fiber optic transceiver, to report these to the user, and/or perform laser shutdown, as appropriate. | {
"pile_set_name": "USPTO Backgrounds"
} |
Aluminum metal is an energy-dense (e.g., greater than 80 MJ/L) fuel with the potential to enhance a variety of common systems. Because aluminum can oxidize in water, it is especially promising as a power source for undersea devices, which are severely limited by the low energy density of conventional anaerobic energy storage media (e.g., less than 1 MJ/L for Li-ion batteries). However, while recent advancements in the scalable depassivation of aluminum have eliminated some barriers to effective energy storage in aluminum, efficient energy conversion from the heat of reaction 2Al+6H2O→3H2+2Al(OH)3+Q remains elusive. This difficulty is mainly attributable to the slow kinetics of the reaction, which are not conducive to maintenance of the steep temperature gradient required for efficient thermal energy conversion. In electrochemical Al-based devices, the continuous loss of some of the aluminum anode due to parasitic corrosion reduces the energy density of the cell and shortens the self-discharge time of the system. Thus, previous attempts to commercialize Al-air and Al-water fuel cells have failed, largely due to the high anodic overpotentials and parasitic anodic corrosion that reduces discharge efficiencies to ˜10-50 percent. | {
"pile_set_name": "USPTO Backgrounds"
} |
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