A method for modeling a mixed-language and mixed-signal (MLMS) design is disclosed. The method includes receiving an MLMS design comprising at least a digital driver, a digital receiver, and an analog block connected by an MLMS net in a hierarchical structure and identifying analog-digital boundaries of the MLMS design. For each analog-digital boundary, the method further includes a) selecting a connect module (CM) by using a predetermined discipline resolution procedure; b) determining input driving values of the CM; and c) connecting the digital driver, the digital receiver, and the analog block to the CM. The method repeats steps a), b), and c) on all analog-digital boundaries of the MLMS design.

Existing analog and mixed-signal (AMS) electronic design automation (EDA) tools, such as the VHDL-AMS and Verilog-AMS languages, have the capability to work with only pure VHDL-AMS or pure Verilog-AMS designs respectively. A detailed description of working with pure VHDL-AMS designs is found in "IEEE Standard VHDL Analog and Mixed-Signal Extensions," published by IEEE-SA Standards Board on Dec. 23, 1999. A detailed description of working with pure Verilog-AMS designs is found in "Verilog-AMS Language Reference Manual—Analog & Mixed-Signal Extensions to Verilog HDL" (Verilog-AMS LRM) published by Accellera International Inc. on Jan. 20, 2003. However, circuit designers are interested in working with design components from both languages, and do not want to be constrained to either the VHDL-AMS language or the Verilog-AMS language.
A challenge in a mixed-language mixed-signal design is to integrate design components of different signal types into one common design. FIG. 1 illustrates an example of a design that consists of digital and analog signal types. The top level Verilog-AMS design 100 includes two instances I1 and I2. The instance I1 102 has a digital port 104 while the instance I2 106 has an analog port 108. The top level Verilog-AMS design further includes an analog net 'a' 110, which may be used to connect the ports of instances I1 and I2. However, due to the incompatibility between the digital port 104 and the analog port 108, a mechanism is needed to bridge between the ports of the two instances I1 102 and I2 106.
The Verilog-AMS language provides a capability to connect between an analog instance and a digital instance. In order to do so, a connect module (CM) is inserted between the respective ports of the instances either manually by the user or automatically by an analog and mixed-signal EDA tool. FIG. 2 illustrates a connect module inserted between the two incompatible instances of FIG. 1. In addition to the instances I1 102 and I2 106, and their corresponding ports 104 and 108, the top level Verilog-AMS design 200 includes a connect module 202, a digital port 204, and an analog port 206. The analog port 206 is configured to connect to the analog port 108 of the instance I2 108. Upon inserting the connect module 202, the digital drivers from the digital port 104 of instance I1 102 are segregated from the digital receivers of the digital port 104. This approach is referred to as driver-receiver segregation (DRS) or segregating driver and receiver (SDR).
One of the problems in supporting a mixed-language mixed-signal design lies in the lack of compatibility between the VHDL-AMS and Verilog-AMS languages. There are a number of incompatibilities between the Verilog-AMS and VHDL-AMS languages. One such incompatibility is the lack of support for the driver-receiver segregation (DRS) methodology by the VHDL-AMS language. The DRS allows accurate modeling of the effects of analog interconnects on digital signal propagation. As shown in FIG. 2, when an analog net is directly connected to a digital net in a Verilog-AMS design, a connect module (CM) is inserted. The CM includes at least one digital port and one analog port. When the CM is inserted between the analog and digital nets, the digital port of the CM is connected to the digital net and the analog port of the CM is connected to the analog net. In this way, Verilog-AMS ensures that digital nets are always connected to other digital nets only and analog nets are connected to other analog nets only. As a part of this DRS process, the digital drivers are segregated from the digital receivers.
There are a number of approaches utilized to address these issues in an MLMS design. One approach is to create a Verilog-AMS wrapper around the VHDL-AMS block such that the connection between this Verilog-AMS wrapper and the VHDL-AMS block are in the same domain. The DRS is then performed within the Verilog-AMS environment. One drawback of this approach is that the user has to know where such connections exist in a design. In a System-On-a-Chip (SOC) design, there can be thousands of such connections. The wrapper modules need to be created manually or using a wrapper tool like NCShell, developed by Cadence Design Systems, Inc. However, the process of identifying these blocks and implementing the fixes or workarounds for such connections consumes a lot of time and effort.
Another approach is to define the Verilog-AMS net that connects to VHDL-AMS net as a domainless net (i.e. nets without a domain or discipline), then the discipline resolution technique is applied to coerce (force) the Verilog-AMS net to be of the same domain as the VHDL-AMS net. However, this approach does not work if a given Verilog-AMS domainless net is connected to both a VHDL-AMS analog net and a VHDL-AMS digital net.
In addition to the limitations described above, other differences between Verilog-AMS and VHDL-AMS languages also impose challenges in implementing DRS in a mixed-language mixed-signal environment. First, the VHDL-AMS language, being a strongly typed language, does not allow connections between analog and digital nets. However, in a mixed-language mixed-signal design, there is a need to connect Verilog-AMS digital components to VHDL-AMS analog components and vice versa.
Second, Verilog-AMS designs and the VHDL-AMS designs are represented differently. Verilog-AMS designs are represented as flattened designs. On the other hand, VHDL-AMS designs are represented as hierarchical designs.
Third, the Verilog-AMS language and the VHDL-AMS language use different semantics for describing a port direction. As a result, drivers in Verilog-AMS and VHDL-AMS are treated differently. Information about the digital drivers from other hierarchical VHDL-AMS levels may not be available at the same time as those from Verilog-AMS. These differences add to the challenges of implementing DRS in an MLMS design.
In summary, there is a need for using previously designed components from both Verilog-AMS and VHDL-AMS languages and taking advantages of the benefits from both languages. The existing workarounds are inflexible and suffer a number of limitations. Therefore, there is a need for implementing the DRS techniques in an MLMS environment that can provide flexible and automated solutions for integrating design components from both Verilog-AMS and VHDL-AMS languages seamlessly.

Modeling a mixed-language mixed-signal design


A positioning system for a geostationary satellite according to the present invention comprises a plurality of outer orbit satellites revolving around the earth in equatorial orbit and polar orbit having higher altitude than that of the geostationary satellite; and at least one control station performing orbit determination using tracking data for the outer orbit satellites, and then transmitting consequent orbit data to the outer orbit satellites. The outer orbit satellites transmit to the geostationary satellite their own navigation data, clock data and correction data generated using the orbit data received from the control station. The geostationary satellite calculates its own position using the navigation data, the clock data and the correction data, and performs position control and attitude control autonomously with onboard sensors and actuators.

The present invention relates to a system that can perform position determination for a geostationary satellite.
In general, geostationary satellites are designed and manufactured to perform their functions autonomously using an onboard computer, sensors and actuators without aid of a control station. However, orbit determination, station keeping and orbit maneuver of the satellite are possible only with aid of a control station. Orbit determination precision of the satellite is not high because the satellite revolves around the earth at the same angular velocity as that for the rotation of the earth on its axis and so the satellite looks stopped when it is observed from the control station. In addition, several dozens of people and lots of money are needed to maintain the satellite until its life is over.
A global positioning system (GPS) of the United States or global navigation satellite system (GLONASS) of Russia is not useful for position determination for the geostationary satellite having higher orbit than that for the above systems because satellites of the above systems have antennas towards the earth on their orbits.

Positioning system for a geostationary satellite


The present invention shows a system for providing a track-bed with a real-life appearance in a model railroad. The system is comprised of three separate components which may be assembled in combination to meet the needs of various track formations. A first component is intended to fit between the track bases of a model railroad track, and both curved and straight variations of the first component are provided. A second component is intended to fit between the track bases of adjoining sections of track, and both curved and straight-sided variations of the second component may be provided, or a single version which may be trimmed to fit either a straight or curved application might be provided. The third component is triangular in cross-section and closes the open sides of the first and second components at the side of the track. The third component is preferably flexible in nature and may be provided in any suitable length. The straight variation of the first component and both straight and curved variations of the second component may be provided in any suitable length, and may be trimmed to fit any track layout situation.

1. Field of the Invention
The present invention relates to a system for providing a track-bed with a real-life appearance in a model railroad. In particular, the present invention relates to a system for providing a track-bed for a model railroad track having a plurality of spaced-apart electrified track rails separated by a plurality of track bases capable of holding said rails raised above a platform surface, and supporting said track rails and any model railroad equipment using said track, said track-bed having a real-life appearance, said system comprising:
a first component having a top surface adapted to provide the appearance of a real-life railroad track bed, said first component having a width at least equal to the largest width of said railroad track, a height slightly less than the distance which the track base raises the track rails, and a length approximately equal to the spacing between the track bases;
a second component having a top surface adapted to provide the appearance of a real-life railroad track bed, said second component having a width at least equal to the largest width of said railroad track, a height slightly less than the distance which the track base raises the track rails, and a length approximately equal to the spacing between two joined track sections; and,
a third component of indeterminate length and comprising a regular right triangle in cross-section with two sides approximately equal to the height of the first and second components, and the surface of the hypotenuse being adapted to provide the appearance of a real-life track bed,
and wherein a section of model railroad track may be adapted to appear life-like by providing at least one first component between the track bases of each section of track, providing a second component between the track bases of each joined section of track, and providing a portion of said third component along the sides of said track section.
2. Description of Related Art
For many years, hobby enthusiasts have enjoyed the operation of model railroad trains, and have lately labored to create life-like settings in which to operate the model trains. Such enthusiasts have been known to go to great lengths to simulate the realism of an actual railroad lay-out, including scale models of buildings, cars and people, which are intricately prepared, painted, and positioned, to create the life-like setting.
One difficulty often encountered in creating such a life-like scene, however, is the original track upon which the model railroad trains run. Because the model versions are electrically powered by an external source of electricity, rather than internally powered by steam or diesel, as their full-size brethren, the tracks must be constructed to carry electrical energy to the model trains. Such original track bears little resemblance to the actual full-scale railroad track bed and when originally designed, the "scale appearance" had no bearing or consequence.
Hobbyists and model makers have created a life-like track, but every scale hobby design requires the painstaking creation of a track and bed which, therefore, is rarely changed. Those who create a layout for seasonal or special occasions do not have the time to create such a track bed and this causes the quality of the presentation to suffer. Also, the ability to break down or change the layout as new trackage is needed normally creates a metal track to wood contact which, because of the model trains weight, can cause a noisy situation.
Alternatively, there has been marketed a rubberized plastic casting into which the model railroad track section can be placed, and these castings can be cast with a life-like design on the surface of the rubberized material to simulate an actual track bed. The difficulty with these castings, however, is that they are not versatile for various scenic applications and can be used only for single track applications without destruction. In addition, because of the need to surround the base portions of the track sections, the castings must be formed of a rubberized material, which is expensive, and has a color and shape which are difficult to alter without destruction.


A method for adapting to observed special use patterns a neural network used to estimate quantities needed by an elevator dispatching system responsible for assigning the elevator or another elevator to a hall call. Rather than simply refining values of existing connection weights to train the neural network to provide acceptable outputs for predetermined inputs, the method analyzes use information to determine whether additional inputs to the neural network might be advantageous and what those inputs might be. If so, the method alters the neural network architecture by providing new input nodes and corresponding connection weights, the connection weights having initially relatively small values. All connection weights can then be adjusted during actual operation of the elevator to accommodate the new input nodes.

1. Technical Field
The present invention pertains to the field of elevator control. More particularly, the present invention pertains to adding input nodes to a neural network used as part of an elevator dispatching system in response to observing use patterns not adequately encoded by the existing network input nodes.
2. Description of Related Art
Elevator dispatching systems use a number of factors in determining which elevator car is the most appropriate to service a request, called a hall call, issued by someone on a floor in the building serviced by the elevator. An elevator dispatching system often uses as an input a so called remaining response time (RRT) in deciding whether to assign an elevator to service a hall call. The remaining response time may be defined as the estimated time for the elevator to travel from its current position to the floor of the hall call.
Artificial neural networks have recently been applied to the problem of estimating RRT. See, e.g., U.S. Pat. No. 5,672,853 to Whitehall et al. Neural networks have proven useful in estimating RRT, but in implementations so far the architecture of the a neural network has been decided before the neural network is put to use, and not changed to accommodate changing patterns of use of the elevator. The architecture of a neural network encompasses what layers are used, the nodes for each layer, and the connections between the nodes. The connection weights, which express how important the output of a first node is for another node to which the first node is connected, are not intended to be encompassed by the term architecture as it is used here.
Usually, the architecture, and in particular the number of input nodes, is determined before the neural network is ever put into service with the elevator. Then the neural network is trained with some training data that reflects what is known about the use of the elevator at the time of training. By training is meant the application of a learning rule, or learning algorithm, that adjusts the weights to provide that each neural network output corresponds properly to values provided to the input nodes.
According to the prior art, once a neural network is put into operation with an elevator, its architecture is static. In other words, if the building population changes or traffic patterns change, the predetermined inputs may not adequately sort out all the factors on which remaining response time could reasonably depend; then the neural network estimate of remaining response time may not be adequate.
For example, one particular floor of a building may differ significantly from the other floors in its need for elevator service. Normally, inputs to a neural network used to estimate remaining response time in an elevator dispatching system are not specialized to particular floors at the outset, unless the special use is anticipated. Thus, after a neural network is put into operation with an elevator, use information collected by the elevator dispatching system may suggest that a particular floor unexpectedly stands out from the other floors in its need for elevator service. Although the neural network weights can be adjusted during actual operation of the elevator, as disclosed in U.S. Patent Application "Method For Continuous Learning By A Neural Network Used In An Elevator Dispatching System" by Whitehall et al., filed on even date herewith, such adjustment may not adequately account for the special use. The existing inputs may simply not be adequate for the neural network to sort out all of the dependencies that should be included in making a good estimate of remaining response time.
What is needed is a way of implementing a neural network so that it can adapt continuously to observed special use patterns that are not adequately represented by existing inputs.

Method for continuously adjusting the architecture of a neural network used in elevator dispatching


A method of removing at least one fork from a forklift carriage includes placing a guard on the forklift carriage to interpose the at least one fork between the forklift carriage and the guard, uncoupling the at least one fork from the forklift carriage at a first coupling location, positioning the at least one fork uncoupled from the forklift carriage at the first coupling location in a fork rack, removing the guard from the forklift carriage, and removing the at least one fork from the forklift carriage. Fork racks, methods, and systems for removing, replacing, and/or storing forks provide additional advantages.

Industrial forklifts or lift trucks are routinely used in industrial and other applications to lift and transport materials from one location to another. The size and shape of the materials and/or crates containing the materials vary depending upon the application for which the forklift is used. In many instances, one size or style forks of the forklift are not properly configured to carry all sizes and shapes of crates or materials without causing damage to the crate or material. In such instances, the forks of the forklift may be replaced or exchanged with other size or style forks. In addition, forks periodically are removed from the forklift for maintenance of the forklift.
Conventional methods of removing and/or replacing the forks of a forklift require the forks to be unlocked and manually manipulated to remove the forks from the carriage assembly of the forklift and to manually carry the forks to a storage area. Due to the relatively large weight of each fork and its relatively unmanageable size and weight distribution, manual handling of the forks by an individual is not only difficult, but is often times unsafe. In addition, forks removed from the forklift are often stored on the ground, on a pile of pallets, etc., which can additionally provide danger to the user. In particular, placing a fork on the floor can cause unwanted back strain while placing a fork on a pile of pallets may lead to an unstable pile of materials that could topple or cause other damage. Therefore, besides being relatively slow, the above procedure of removing or replacing and storing forks often times contributes to injury such as back strain, pinched fingers, injured toes, etc.

Forklift guard, fork rack, and associated methods


Pivoting arrangement of an emergency exit hatch of an elevator, the arrangement being for a surrounding frame structure, a roof element of an elevator, and an elevator, in which arrangement the emergency exit hatch of the elevator is a planar element, and includes pivot brackets on its opposite sides, and the frame structure includes an aperture, which the hatch is arranged to cover, and which aperture includes pivot apertures in its opposite sides, for receiving the pivot brackets, and the planar hatch element and/or the frame structure is/are fabricated from plate material, and the part of the frame structure including a pivot aperture and/or the part of the hatch including a pivot bracket is/are of the plate material.

Elevator cars are conventionally formed to comprise a load-bearing frame structure, i.e. a car sling, which comprises a lower horizontal beam system and an upper horizontal beam system, as well as a vertical beam system of a first side and a vertical beam system of a second side, which beam systems are connected to each other so that they form a closed ring, inside which is an interior comprised in a car box fixed to the beam systems, which interior can receive goods and/or passengers for conveying them in the interior of the elevator car.
The elevator car of the elevator can also be fitted inside a car sling composed of a top element, a bottom element and also side elements, i.e. vertical elements. The car and car sling can if necessary also be integrated into each other.
The outer surface of the roof of an elevator car is generally formed from plates that are firmly and rigidly supported on the upper horizontal beam system. According to prior art, there is a separate roof panel in elevator cars, below the upper horizontal beam system and the aforementioned plates forming the outer surface.
According to national and international regulations, connected to the structure of the outer surface of the roof of the elevator car is an emergency exit hatch, which is often hinged with fixed hinges to the roof structure. A roof structure of an elevator with an emergency exit hatch provided with fixed hinges is awkward and expensive to manufacture and separate fixing means are needed for installing the roof hatch as well as special tools for fixing the hinges. In addition, separate locking means are needed for locking the emergency exit hatch, which again increases the amount of parts needed and thereby the manufacturing costs, installation costs and servicing costs of the product.
Installing fixed hinges in the emergency exit hatch also essentially limits the opening direction of the hatch. Retrospectively changing the opening direction of an emergency exit hatch provided with fixed hinges is awkward and expensive, requires that the fitter has many special tools, and in some cases might even be impossible owing to the roof structure of the elevator.
Generally speaking, one problem, among others, with solutions according to prior art, such as e.g. the solution presented in publication GB2116601A, can be considered to be the non-optimal construction. More particularly the roof structure of the elevator car has not been optimized as an entity sufficiently from the standpoint of space usage and of the complexity of the construction. All the essential factors have not been simultaneously taken into account to an adequate extent, more particularly the number of parts of the roof structure of an elevator, and the techniques for manufacturing them, have not been optimal. Simplification of the roof structure and a reduction in the number of parts therefore directly impacts manufacturing costs, installation costs and servicing costs, and also increases the reliability of the elevator and reduces the structural weight of the elevator thereby lowering energy consumption and reducing operating costs. Each gram by which the structural weight, and thus the energy consumption, of the elevator can be reduced is important.

Pivoting arrangement, roof element and elevator


There is disclosed in embodiments catalysts produced by a two-stage loading of a zeolite carrier with an aqueous solution of a cobalt compound, with drying in an air current after each loading. Methods using the catalysts to produce synfuel are disclosed.

All references cited in this specification, and their references, are incorporated by reference herein where appropriate for teachings of additional alternative details, features, and/or technical background.
1. Field of the Invention
The invention pertains to the field of catalyst production, and in an embodiment more particularly, to the creation of improved cobalt-zeolite catalysts for the synthesis of hydrocarbons (synfuels), e.g. C5-C10 aliphatic hydrocarbons, with CO and H2 Via Fischer-Tropsch chemistry.
2. Description of Related Art
Synfuel (synthetic fuel) is again becoming increasingly important existing readily-available petroleum stores are being rapidly depleted. It has been known for some time that carbonaceous materials, such as coal, shale oil, or biomass, can be converted by pyrolytic gasification with steam to produce "syngas," a mixture of CO and H2. One method for converting such syngas into hydrocarbons is the Fischer-Tropsch process invented by German researchers Franz Fischer and Hans Tropsch in the 1920's. The original Fischer-Tropsch process may be described as such:(2n+1)H2+nCO→CnH2n+2+nH20
The use of Fischer-Tropsch chemistry in the conversion of syngas has been touted as a means to meet fuel needs in petroleum-poor countries.
A major fraction of the hydrocarbons typically produced by Fischer-Tropsch chemistry contain between 5 and 10 carbon atoms (C5-C10) in an aliphatic chain. These hydrocarbons can be used directly, for example, as components of motor fuels or as feedstocks for further chemical modification. It is often desirable to produce hydrocarbons with a high fraction of isoparaffins, because these branched compounds improve the octane rating of the synfuels.
Fischer-Tropsch chemistry typically employs catalysts to aid in the conversion of syngas to hydrocarbons. Published procedures exist for generating a catalyst for synthesizing hydrocarbons, in particular CD5-C10 aliphatic hydrocarbons, from "synthesis gas" that is, CO and H2.
In one procedure described at [1] in the references cited below, the catalyst may be obtained by the combination of basic cobalt carbonate with a pentacil-type zeolite substrate, such as zeolite ZMS-5. A drawback of this described method for some may be the relatively low selectivity for isoparaffin formation. As indicated in [1], the content of isoparaffin hydrocarbons obtained by such a catalyst may not typically exceed 43%.
In another procedure described at [0002] for generating a catalyst for the synthesis of C5-C10 aliphatic hydrocarbons from CO and H2, a zeolite carrier is suspended in a solution of cobalt nitrate, mixed in vacuum, dried by microwave heating, and subsequently baked at 500° C. A potential drawback of the method set forth in [2] is that it may be technically difficult to execute.
Another Fischer-Tropsch catalyst formation procedure, which is described by one of the present inventors, is set forth at [3] by Lapidus et al. In this case the zeolite-carrier is loaded with a solution of dicobaltoctacarbonyl in n-hexane. This mixture is subsequently processed with H2 at 150° C. The drawback of this method is the low activity of the catalyst obtained. When used in a flow reactor the output of liquid hydrocarbons may not exceed 37 g/s from 1 m3 of the synthesis gas passing through the system. The catalyst also may show low selectivity for forming isoparaffin hydrocarbons; with failure to exceed 44% of the reaction mixture [3].
As described above, there exists a need for higher-activity, higher-selectivity catalysts for synthesizing synfuels from syngas, as well as a need for providing synfuels with high isoparaffin content.
These needs may be met by embodiments of the invention described herein. In one embodiments there is zeolite-carriers subjected to a two-stage saturation with an aqueous solution of cobalt nitrate, with an intermediate step of drying in an air current at temperatures of about 350° C. to about 450° C. Subsequent drying on a water bath optionally may complete the catalysts. The need for fuels for high isoparaffin content may be met by synthesizing liquid hydrocarbons from CO and H2 using the new catalysts via embodiment methods described below.

Catalysts and methods for synthesizing aliphatic hydrocarbons from CO and H


An apparatus includes a plurality of sets of block members having respective pictorial and numerical designations, wherein each set includes duplicates of pictorial and numerical representations that are selected from a face-down relationship relative to one another in an effort to attempt to match such duplicates. The block members are optionally arranged for mounting within a support member to secure and position the sets for use and storage.

1. Field of the Invention
The field of invention relates to game apparatus, and more particularly pertains to a new and improved memory block game apparatus wherein the same is arranged to attempt to pictorially represent matching pictorial and numerical designations relative to a plurality of sets of blocks.
2. Description of the Prior Art
Game apparatus for entertainment and amusement of individuals is indicated in U.S. Pat. Nos. 4,416,455 and 4,852,878 for the use of letters and pictorial representations in use of the game structure.
U.S. Pat. No. 4,812,123 sets forth an educational device to attempt to assist in teaching of mathematical computation and the like.
The instant invention sets forth a game apparatus wherein the same is arranged to attempt to associate like and matching pairs of respective numerical and pictorial representations and in this respect, the present invention substantially fulfills this need.


A light-condensing member includes a base plate, a main light-condensing pattern formed on the base plate, and a sub light-condensing pattern formed on the main light-condensing pattern. The main light-condensing pattern includes a plurality of main prisms extended in a first direction. A cross section of a main prism taken along a second direction substantially perpendicular to the first direction has a substantially triangular shape. The sub light-condensing pattern includes a plurality of sub prisms formed on the main prisms and extended in a second direction substantially perpendicular to the first direction. A cross section of a sub prism taken along the first direction has a substantially triangular shape. Since light is condensed simultaneously in both a horizontal direction and a vertical direction through one light-condensing member, manufacturing costs and the thickness of backlight assembly are reduced.

1. Technical Field
The present disclosure relates to a light-condensing member capable of reducing a manufacturing cost and a thickness by reducing the number of elements, a method of manufacturing the light-condensing member and a display apparatus having the light-condensing member.
2. Discussion of the Related Art
A display apparatus may be employed by information-processing devices such as a notebook computer, a monitor, and a terminal of mobile communication. Various kinds of apparatuses, such as a cathode ray tube (CRT), and a plasma display panel (PDP) may be used as a display apparatus. However, a liquid crystal display apparatus (LCD), which uses a liquid crystal to display images, has been widely used as a display apparatus.
The liquid crystal display apparatus displays images by using liquid crystal, which has optical and electrical properties such as an anisotropic refractive index, and an anisotropic permittivity. When compared with other display apparatuses such as CRTs, and PDPs, the liquid crystal display apparatus is thinner, lighter, uses less driving voltage, and consumes less power.
The liquid crystal display apparatus includes a liquid crystal display panel. The liquid crystal display panel has a liquid crystal layer disposed between two substrates, for example, a lower substrate and an upper substrate. The liquid crystal display panel displays images by changing light transmittance caused by changing the alignment of liquid crystal molecules of the liquid crystal layer.
The liquid crystal display panel is non-emissive device that does not emit light. Therefore, the liquid crystal display apparatus employs a backlight assembly to provide the liquid crystal display panel with light.
A conventional backlight assembly may include a lamp emitting light, and a light guide plate guiding a path of the light. The light, which is provided from the lamp disposed at a side of the light guide plate, is guided by the light guide plate toward a liquid crystal display panel disposed over the backlight assembly.
The backlight assembly may further include a plurality of light-condensing sheets disposed over the light guide plate to condense light exiting from the light guide plate. The light-condensing sheets may include a first light-condensing sheet to condense light along a first direction, and a second light-condensing sheet to condense light along a second direction that is substantially perpendicular to the first direction.
The use of two of light-condensing sheets to condense light simultaneously in the first and second directions increases the manufacturing cost and a thickness of the display products.

Light-condensing member, method of manufacturing the same and display apparatus having the same


A head up display for vehicles includes: at least one light source; at least one light guide set in front of the light source; an image panel set in front of the light guide; and a surface with the feature of at least partial specular reflection. Wherein the light emitted from the light source illuminates the image panel via the light guide to project an image on the image panel onto the surface and then be reflected to an observer, so as to form a virtual image observed by the observer. The light guide of the present invention can reduce the light loss of the head up display for vehicles and make the illumination light on the image panel more homogeneous and possessing high directionality, and so as to improve the brightness and quality of the virtual image formed by the head up display for vehicles.

1. Field of the Invention
The present invention relates to an image display system, and more particularly, to a head up display for vehicles which is viewed through a specular or partially specular reflection surface.
2. Description of the Prior Art
Conventionally, the projector is often used in the meeting, business briefing, teaching and training. During the recent years, the technology of imaging module and display, such as the Liquid Crystal Display (LCD), Digital Light Processing (DLP) or Liquid Crystal on Silicon (LCOS), progress very rapidly. Therefore, the products which combine the imaging module and the display are increasingly applied for versatile fields, for example, the home drama, helmet display, small portable display and Head-Up Display (HUD).
Normally, the conventional projection displays project images onto a reflective surface or a screen, which have a diffusive reflection characteristic. Thus, their applications are very limited.
Head up display (HUD) is originated from the aviation technique, but the conventional aviation HUD is complex and bulky, and its setup location and magnification are fixed and unadjustable, and such that it is very expensive.
Along with the advancing of technology, presently the HUD is more and more popular for the application of automobile, but the HUD for vicheles uses traditional direct-view display as the image source, whose angular emission profile is highly diffusive which results in low brightness or requires high driving power to meet a specified brightness.


A plurality of terminal devices, e.g., game apparatuses 2 are interconnected to each other through a network 4. The respective game apparatuses 2 receive signals inputted from the outside, e.g., television signals broadcast from a broadcasting antenna and extract synchronizing signals from the broadcasting signals. Based on the extracted synchronizing signals, the respective game apparatuses 2 make synchronization control of operations, data communication among the respective game apparatuses 2. The respective game apparatuses 2 use the common signals to make the synchronization control, whereby the respective game apparatuses 2 can be synchronized with one another suitably without timing shift. The terminal devices synchronizing method can suitably synchronize timings of communication among a plurality of terminal devices.

The present invention relates to a terminals synchronizing method for synchronizing a plurality of terminals interconnected by a communication line. The present invention relates to a communication system including a plurality of terminals interconnected by a communication line. Furthermore, the present invention relates to terminal devices interconnected by a communication line.
Recently, games played through communication line (such games will be hereinafter called network games) are noted. Network games in which car races are competed by a plurality of game players on a plurality of game apparatuses installed side by side in game centers or others and interconnected to one another through communication line are known as popular games.
In a case of game apparatuses installed side by side in a game center or others, as shown in FIG. 10, a plurality of network game apparatuses 101, 102, 103 are interconnected directly to one another by a cable, and one, e.g., the network game apparatus 101, of the network game apparatuses 101, 102, 103 is a host. The host network game apparatus 101 supplies synchronizing signals to the rest network game apparatuses 102, 103, and the rest network game apparatuses 102, 103 time a start of game processing with the synchronizing signals. The network game apparatuses 101, 102, 103, which are installed near one another, have little delay due to interconnection by the cable, and good synchronizing control can be realized.
Recently especially noted are network games played on game apparatuses geographically spaced from one another by connecting the game apparatuses to networks, such as interest, etc., through communication line, such as telephone line. Furthermore are proposed network games which will be played by connecting not only game apparatuses installed in game centers, etc. but also domestic game apparatuses to networks.
However, in a case of geographically spaced game apparatuses, delays of the communication line, the networks, etc. are large, which makes it impossible to use the above-described method to synchronize the game apparatuses with the host game apparatus.
Accordingly, in network games by connecting geographically spaced game apparatuses to networks, the respective game apparatus make data processing and image processing in synchronization with signals of their own transmitters. Also in communicating with the rest game apparatuses and the center, the respective game apparatuses communicate at a certain interval (1 int) with respect to a signal of their own transmitters. The respective game apparatuses take in data supplied by the rest game apparatuses to make data processing and image processing.
However, the transmitters of the respective game apparatuses have errors with respect to the transmitters of the rest game apparatuses, and the respective game apparatuses have communication intervals different from one another. Resultantly, when the errors are accumulated, the respective game apparatuses cannot receive data from the respective game apparatuses and cannot make data processing and image processing. Thus, even when high-speed data communication is realized, for games requiring precise timing control, suitable game processing cannot be made due to the timing offset.
An object of the present invention is to provide a method for synchronizing terminals which can suitably synchronize timings of communication among a plurality of terminals.
Another object of the present invention is to provide a communication system which can suitably synchronize timings of the communication among a plurality of terminals.
Further another object of the present invention is to provide a terminal device which can synchronize communication timings.

Terminal devices synchronizing method communication system and terminal device


An entertainment system includes an application program recording system which record an application program which can input at least one command of operation an which the player sets the action of the character on a display screen. The command is stored in an action set frame in the unit of one operation to action set frame used to create the movements of the player character. The system further has an input, operation system where the player inputs instructions and a control system which controls the operation of the player character on the display screen based on the command from the application program recorded by the application program record system and the input operation system.

1. Field of the Invention
The present invention relates to a recording medium in which a program for a game where actions of a player character in a virtual world is simulated by the key input of the player is recorded, and an entertainment system using the program that has been read from the recording medium.
2. Description of the Prior Art
Role-playing games have become popular where the player performed a fixed role in the virtual world, and in most cases advanced towards an assigned goal while experiencing realistic adventures. In such role-playing games, the player controls the actions of the character by key input operation, and the action of the character can be simulated.
In the aforementioned role-playing games, since only a single command describing the behaviour of the character could be set in one operation, it was not possible to program consecutive movement of a character. This has resulted in game content that was poor in imparting a feeling of player""s presence in the game scene. Moreover, the game content left players dissatisfied due to the simplicity of operations and the inability to carry out highly developed operations commensurate with the progress of the game.
Taking the above mentioned facts into consideration, the present invention allows the character to execute consecutive movements and offers an entertainment system which uses the program recorded in its recording medium to simulate realistic actions.
To solve the above mentioned problem, the recording medium related to the present invention stores the program which advances the game by recording key input of the player that makes a fixed character in the display screen act according to the intention of the player. In order to store the action of the above-mentioned fixed character within one action frame of the above-mentioned display, a program capable of storing at least one command related to the action of the above mentioned fixed character, is stored in the recording medium.
Here, the total allowed score for the actions in that action set frame and the corresponding action points for each type of the commands are set up beforehand, and if the action point total is within the permissible action points for the action set frame, the stored program is designed to input two or more of above mentioned commands.
In addition, when two or more of said commands in a said action set frame corresponds to a predefined pattern, the stored program converts the said multiple commands to a special command.
Moreover, in order to solve the above mentioned problem, the entertainment system of the present invention, where a player simulates the movements of the player character in the virtual world through the manipulation of key input, comprises an input device for a player command input operation, a storage medium which records a program capable of receiving at least one of the commands in one operation step for the action set frame that is used to set up the action of the player character, and a control device to control the movement of the player character on the display screen based on the command input through the input device as well as the program stored in the storage medium.
Here, the program is read from the recording medium where the said program is recorded into the said storage medium. Moreover, the program can be accessed and stored in the storage medium through communication means.
Moreover, the control means enables to record two or more of the action commands when the action command points are within the total action points allowed within the action set frame where the action points corresponding to each action command and the total allowed action points in said action set frame is assigned beforehand.
Moreover, when the order of two or more of said commands in the acting set frame corresponds to a predefined pattern, the control device converts the two or more of said commands into a special command.
Thus, as the present invention makes it possible to input commands with different lengths as long as the length of the action set frame is not exceeded, compound commands to carry out continuous action of the character can be generated.

Recording medium and entertainment system


Systems, methods and apparatus are provided for controlling an agricultural implement having a plurality of row units. In some embodiments, seeds are planted by rotating a seed disc in a first direction; seeds are then unloaded from a seed disc into a seed pool by rotating the seed disc in a second direction. In some such embodiments an amount of rotation in the second rotation is selected to ensure that seeds are released into the seed pool and not released from the from the seed meter.

Increased seed costs and increased awareness among farmers of the agronomic costs of poor seed placement have driven the development of systems for improving seed placement. Systems and apparatus have been developed for stopping seed meters at a desired location using clutches to stop a hydraulically-driven shaft from driving a seed meter, or in the case of electrically driven seed meters, using a signal to command the associated electric motor to stop. However, such systems and apparatus still allow seeds to be dropped from the seed meter in undesired locations after the motor or shaft is stopped. Thus there is a need in the art for systems, methods and apparatus of stopping a seed meter without dropping unwanted seeds from the meter; e.g., unloading a seed meter.

Seed meter unloading systems, methods, and apparatus


An interactive respiratory regulator comprising a recording device recording the respiratory pattern of a user and issuing a corresponding respiratory signal, an instruction signal generator for the generation of an instruction signal that can be perceived by the user in order to influence his respiratory behavior, a control device controlling the instruction signal generator, a processing device which determines by means of a parameter of the respiratory signal received, whether the recorded respiratory pattern during a predetermined time span meets a pre-adjustable standard for this parameter, and which at a certain error percentage sends a starting signal to the control device. The interactive respiratory regulator is characterized in that the processing device processes as parameter the ratio between the in- and exhalation time in a respiratory cycle. In a preferred embodiment the processing device includes the frequency of the respiratory cycles as second parameter and the pre-adjustable standard comprises also a value for this parameter.

1. Field of the Invention
The invention relates to an interactive respiratory regulator comprising:
a recording device recording the respiratory pattern of a user and producing a corresponding respiratory signal, PA1 an instruction signal generator for generating an instruction signal that can be perceived by the user in order to influence his respiratory behavior, PA1 a control device controlling the instruction signal generator, PA1 a processing device which determines by means of a parameter of the respiratory signal received whether the respiratory pattern recorded during a predetermined time span meets a pre-adjustable standard for this parameter, and which at a certain error percentage sends a starting signal to the control device.
2. Description of Related Art
An apparatus of this kind, indicating to a user a desirable respiratory pattern, is known from the Netherlands patent specification 166.850, whereby this apparatus, In particular to combat the hyperventilation syndrome, is provided with a device for determining the cycle time. The corresponding frequency of the respiratory cycles is applied as parameter for the respiratory pattern. The recording device, being for instance a strain gauge or a mercury wire recorder applied to the chest of the user, produces a pulse signal with a repeat frequency corresponding with the respiratory frequency. This signal is fed to a time-determining device which compares this frequency with a present standard or limit value. As soon as this processing device determines that the respiratory frequency is higher than the limit frequency it will set off a sound generator which during each respiratory cycle produces two, for the patient audible and differentiable tones.
However, not only patients suffering from hyperventilation, the symptom of which is an abnormally high respiratory frequency, exhibit a non-optimal respiratory behavior, but also users who suffer, for instance, from phobias or psychic traumas of any kind.
Describing the pattern of such a non-optimal respiration solely in terms of respiration frequency was shown not always to be adequate. The present invention ensues from the search for a useful, instructive feedback to the user with non-optimal respiratory patterns including others besides those which occur through hyperventilation. On these grounds it has been concluded that in order to analyze a respiratory pattern correctly, knowledge of especially the ratio between the in- and exhalation times is indispensable. The pause after exhalation is also an important parameter.
The known apparatus described above has, however, the limitation that it does not include that necessary extra information in the feedback process, thus offering insufficient possibilities for application to remedy disorders or to correct deficient respiratory patterns in general.


The invention relates to a multiplexer for a digital switch, arranged to be included in a switch network whose data flow is organized in frames containing a number of time slots, said time slots including data time slots, which shall be directed through the switch from first to second sets of terminal units, such as subscriber connections, trunk connections, processors, etc. The multiplexer is controlled by a processor for controllable multiplexing, i.e., mapping of a number of transmission links from each of a corresponding number of the terminal units of said first set to a transmission link leading to the switch, as well as of a transmission link leading from the switch to a number of transmission links leading to each of a corresponding number of terminal units of said second set. The mapping is performed on the data time slots. All data time slots arriving from the terminal units of said first set are to be sent forward via a first buffer to the switch in an order which is determined by a first control memory for the mapping, and all data time slots arriving from the switch are to be sent forward via a second buffer toward the terminal units of said second set in an order which is determined by a second control memory for the mapping. The buffers are implemented as fifos, one for each of the links from and to the terminal units.

The present invention relates to a multiplexer for a digital switch, which is arranged to be included in a switch network, the data flow of which is organized into frames containing a number of time slots including data time slots, which shall be connected through the switch from first to second sets of terminal units, such as subscriber connections, trunk connections, processors, etc., wherein
the multiplexer is controlled by a processor for controllable multiplexing, i.e. mapping, of
a number of transmission links from each of a corresponding number of the terminal unit of said first set to a transmission link leading to the switch, as well as of
a transmission link leading from the switch to a number of transmission links to each of a corresponding number of terminal units of said second set, said mapping being performed on the data time slots, wherein
all data time slots arriving from the terminal units of said first set are to be sent via first buffer means to the switch in an order determined by a first mapping control memory, and
all data time slots arriving from the switch are to be sent via second buffer means toward the terminal units of said second set in an order which is determined by a second mapping control memory.
More particularly, the switch can be a time-space switch of a kind described in more detail in Swedish patent application 9103719-2. Therein it is additionally disclosed that on the transmission links there also occur, besides the data time slots, control time slots containing packet data for controlling the switch.
When several transmission links are mapped together it is important that this occurs with little delay, and that time slot integrity is retained, that is, the time slots arrive in a correct order. A certain delay is required, however, to avoid risking that data is read before having been written, since time slot integrity is then lost.
Therefore, it is important that time slot integrity can easily be checked, which is difficult if the buffers required for the mapping function are realized with usual memories.

Controllable multiplexer for a digital switch


One embodiment of the present invention provides a system for high-throughput asynchronous communication that includes a sender and a receiver. A sender's first-in, first-out (FIFO) buffer is coupled to an input of the sender, a receiver's FIFO buffer is coupled to an input of the receiver, a forward communication channel is coupled between the sender and the receiver's FIFO buffer, and a reverse communication channel is coupled between the receiver and the sender's FIFO buffer. The forward communication channel, the receiver's FIFO buffer, the reverse communication channel, and the sender's FIFO buffer operate collectively as a network FIFO between the sender and the receiver. The network FIFO is configured to ensure that asynchronous communication between the sender and the receiver takes place reliably and without unnecessary waiting by the sender or the receiver.

1. Field of the Invention
The present invention relates to communication networks. More specifically, the present invention relates to an apparatus and a method for high-throughput asynchronous communication over high-latency communication channels.
2. Related Art
Dramatic increases in computational speed in recent years have largely been facilitated by improvements in semiconductor integration densities, which presently allow hundreds of millions of transistors to be integrated into a single semiconductor chip. This makes it possible to incorporate a large amount of computational circuitry onto a semiconductor chip. Moreover, the small circuit dimensions made possible by improved integration densities have enabled this computational circuitry to operate at greatly increased speeds. While computational circuitry is growing increasingly faster, the delay involved in transferring data between system components is becoming more of a bottleneck.
For example, FIG. 1 illustrates communication channels between a sender 102 and receiver 104. The forward latency between sender 102 and receiver 104, including the delay in the forward channel 108, is df and the reverse latency between sender 102 and receiver 104, including the delay in the reverse channel 106, is dr. The network behaves like a one-stage FIFO with a cycle time of dr+df. The problem with the network of FIG. 1 is that the throughput of this communication network is low, because the cycle time is the sum of the large forward and reverse latencies.
When sender 102 sends a data item to receiver 104 through forward channel 108, receiver 104 receives the data item at an elapsed time of df. After receiver 104 receives the data item, receiver 104 places an acknowledge token into reverse channel 106 to acknowledge receipt of the data item. At an elapsed time of dr, sender 102 receives the acknowledge token and is free to send another data item to receiver 104. If sender 102 attempts to send a second data item before receiving the acknowledge token, it is possible for the second data item to be lost, or to corrupt the first data item.
The cycle times df and dr can be reduced somewhat by moving the components closer together. However, even when the components are touching each other, the cycles times continue to be very large compared with the cycle times of the individual circuits within the components.
Hence, what is needed is an apparatus and a method for high-throughput asynchronous communication between a sender and a receiver without the problems described above.

Apparatus and method for high-throughput asynchronous communication


A method for setting an address of a rank in a memory module having a number of memory chips distributed along a byte lane includes setting the first memory chip of the byte lane to have a first rank address, generating a second rank address therein from the first rank address, and driving the second rank address to a second one of the memory chips. Alternatively, the first rank address may be driven to the second memory chip, and then, a second rank address is generated in that second memory chip. Further, the second memory chip is set to have the second rank address in response to the driving the second/first rank address. A power-up sequence after voltage supply, or command signals sent via a serial management bus or the command address bus can be used to initiate the setting of ranks. The rank addresses are re-driven to adjacent memory chips by DQ-lines along a byte lane.

A memory module of a computing device, such as a PC or workstation, is commonly arranged in terms of ranks. A rank comprises that number of memory chips, which, in sum, provide that number of data lines which corresponds to the width of a bus used to store data in the memory module by, e.g., a controller or a chip set. Typically, the bus width amounts to 64 bits. A rank thus defines a 64 bit wide area in memory. Including an error correction code (ECC), a rank defines a 72 bit wide area.
There are memory chips, which are accessible by four ("×4") or eight ("×8") data lines for retrieving data stored in a respective memory array. Correspondingly, a rank comprises 16×4-chips or 8×8-chips (including the ECC: 18×4-chips or 9×8-chips). A double-sided memory module may then, e.g., comprise 1, 2, or 4 ranks.
In order to write to or read data from a memory module, each rank has a known unique rank address. There are at least two possibilities depending on the kind of connection between the controller or the chip set, and each of the memory chips.
According to a first implementation the controller has additional lines, which afford a connection to each of the memory ranks in parallel. A further chip select signal is necessary to address the respective chips of a desired rank. In this case, which is represented by semiconductor memory modules of type DDR1-DDR3 (DDR: double data rate), further pins are needed with respect to the connector of the memory module, which represents a disadvantage in view of space saving and current reduction.
According to a second implementation, each memory chip (package) is provided with, e.g., two additional balls of a ball grid array (BGA). Both additional balls, which are then hardwired on a DIMM (double inline memory module) together define a rank address, which the chip belongs to, e.g., one of the four rank numbers 0-3. Thus, when a write command is issued, it is driven along with a transferal of the corresponding rank address (0-3). However, recent efforts trying to reduce the number of balls on a chip package in order to reduce footprint and increase the storage density are disadvantageously counteracted by that solution.
To reduce the amount of wiring and/or number of balls or pins needed to address memory chips of a memory module with respect to a memory controller or a chip set, and to increase storage density and readout velocity of semiconductor memory modules are desirable.

Method for setting a second rank address from a first rank address in a memory module


The present invention relates to biosensors having improved sample application and measuring properties and their uses for detection, preferably, quantitative measurement, of analyte in a liquid sample. In particular, the invention provides for a biosensor having a sample application, reaction area and liquid soluble hydrophilic material facilitating the speed and uniformity of sample application, especially small volume sample application, via capillary flow. Methods for assaying analytes or enzymes using the biosensors are further provided.

A biosensor is an analytical device that comprises at least two components: an immobilized biological component responsible for the selective recognition of the test species and a suitable transducer device responsible for relaying the biological signals for further analysis. Among others, electrochemical biosensors that employ biological recognition systems and electrochemical transudation offer a possibility of quick and real-time analysis, which is particularly suited for the rapid measurement of point-of-care industry. The evolution of these devices comes from the multi-discipline of electronics, material science, electrochemistry, biochemistry, and immunochemistry. The technology of electroanalysis is an interplay between electricity and chemistry that concerns current, potential, and charge from a chemical reaction. There are two principal types of electroanalytical measurements, potentiometric and amperometric. Potentiometric technique is a static technique with no current flow; the established potential across the ion-select membrane is measured. With different types of membrane materials, the recognition of different ions can be reached. Thus, the potentiometric probes have been widely used for directly monitoring ionic species such as calcium, potassium, and fluoride ions. In amperometric technique, an electrode potential is used to drive an electron-transfer reaction. The responsive current is measured and related to the presence and/or concentration of the target analyte. In the past, potentiometric devices have been more widely applied in clinical chemistry laboratories. But with increasing amount of research on amperometric systems in diagnostics, the balance has shifted. The amperometric biosensors make possible a practical, fast, and routine measurement of test analytes. One trend of current biosensors focuses on the methodology of minimum demand of operator skills.
To date, most commercially used biosensors are amperometric ones that harness redox enzymes as recognizing biocomponents and electrodes as electrochemical transducers. The mass production of inexpensive and disposable devices has been achieved recently with the help of screen-printing technology. The success in the development of these devices has led to amperometric assays for several biomolecules including glucose, cholesterol, and various drugs. This type of amperometric biosensor is typically composed of an base member, two or three electrodes, an insulating layer, and a region for enzymatic reaction. Two-electrode biosensor consists of a working electrode, a counter electrode and a destined region where reagent for enzymatic reaction is placed. The reaction progresses when the sample liquid containing an analyte is applied onto the reaction area. Two physical effects, mesh spread and capillary action, are commonly used to guide a uniform distribution of the loaded sample on the reaction area. After the reaction is complete, the test analyte is oxidized and the electrons yielded from the reaction are trapped in a reduced co-product. A controlled-potential is then applied between the electrodes to trigger a second round of oxidoreduction. This electrical potential must be sufficient enough to drive a diffusion-limited electrooxidation at the surface of the working electrode, yet insufficient to activate irrelevant chemical reactions. After a time delay, the current produced by the electrochemical oxidoreduction is observed and measured and the current is correlated to the presence and/or amount of the analyte in the sample.
In the case of oxidation, oxygen is consumed in the oxidative reaction as a co-reactant and hydrogen peroxide is yielded as a co-product. The yield of hydrogen peroxide is proportional to the concentration of analyte. Hydrogen peroxide can be detected by oxidizing it at anodic potential (e.g., >0.6 V, Ag/AgCl) to generate an electrical signal (current). However, the potential required for oxidizing hydrogen peroxide can cause oxidation of other oxidizable chemicals such as ascorbate, bilirubin, uric acid, and the commonly used drug, e.g., acetaminophen, thus leading to an interference of electrical current to be detected. This interference can be avoided by replacing oxygen with an artificial mediator capable of transferring electrons from oxidoreductases. Several mediators have been used to enhance electron transfer between a variety of enzymes and electrodes, which include ferrocene and its derivatives, osmium complex, tetrathiofulvalene, phenazine ethosulfate, benzoquinone, and hexacyanoferrate.
Conventional methods of determining analytes in blood involves sample pretreatment. However, as pretreatment involves extra time and labor, these assays may benefit through the availability of a direct measurement of whole blood samples. More importantly, direct measurement of whole blood samples makes it possible for a real time monitoring for home users. For accurate measurement of a whole blood sample using an amperometric biosensor, a quick and homogenous reaction on the electrodes is essential for successful analyte determination. Reagents dried on a reaction area, including an oxidoreductase and a mediator, have to dissolve instantly when a small volume of sample blood is applied to the biosensor. These dissolved reagents must mix with the sample thoroughly for the completion of the enzymatic reaction and consistency of the subsequent electronic reaction.
The other common problems for assaying biological samples such as the whole blood are sample viscosity and the relatively large sample volume for the analysis. The whole blood sample, with its viscosity, might not be able to be distributed over sufficient reaction area. Moreover, viscosity and surface tension of samples may present a lag-time in sample introduction to the reaction area in biosensors, thus inhibiting real-time analysis of particular analytes. For some poorly bleeding people, it might be a problem to get enough blood from a prick on fingerstick. Three types of insufficient application of blood (or other viscous samples) have been observed: first, the sample covers only the front end of the test strip; secondly, the sample covers only the right half of the strip; and thirdly, the sample covers only the left half of the strip. The insufficient or non-homogenous application of sample fluid presents a lower amount of analyte, which causes an artificial and misleading result.
Moreover, with particular regard to glucose assays, current devices may only provide accurate results within a particular glucose range. This range may lie outside and below the range of particular diabetic patients which need a reliable indicator of blood glucose levels.
Another problem with current biosensors includes their instability at a range of temperatures, in that a difference in ambient temperature can alter the characteristics of the reaction area. This type of alteration may affect the speed of sample uptake into the device and overall accuracy due to incomplete loading of the sample.
Accordingly, there is a need in the art for biosensors and methods that provide for improved sample application and measuring properties. The present invention addresses this other related needs in the art.

Biosensors having improved sample application and uses thereof


A loss of signal condition is evaluated for an input data stream according to a signal strength threshold level. The signal strength threshold level is determined according to a supplied loss of signal (LOS) threshold level. Two hysteresis modes are used to ensure the hysteresis at low LOS threshold levels is sufficient. The first mode uses hysteresis for the signal strength threshold level that is proportional to the LOS threshold level when the LOS threshold level is above a predetermined level. The second mode employs fixed hysteresis for the signal strength threshold level when the LOS threshold level is below the predetermined level. The hysteresis provides a signal strength threshold level that has a greater magnitude on deassertion of a loss of signal indication than on assertion of the loss of signal indication.

1. Field of the Invention
This invention relates to integrated circuits used in communication systems and more particularly to determining loss of signal conditions associated therewith.
2. Description of the Related Art
Interruptions occur in data transmission for a variety of reasons such as equipment failure, a cut cable or excessive attenuation of the signal. When such an interruption occurs, it is typical for the intended receiver in the data transmission system to detect the failure condition and inform the communication system of the existence of the failure. Many communication systems specify various aspects of detecting such loss of signal (LOS) conditions. For example, the Synchronous Optical Network (SONET) specification requires that LOS be raised when the synchronous signal (STS-N) level drops below the threshold at which a bit error rate (BER) of 1xc3x9710xe2x88x923 is predicted.
A clock and data recovery circuit operating in such a communication system typically receives the input data stream as a differential signal. One approach to detecting loss of signal conditions has been to rectify the received signal and compare the received signal to a reference level. Peak detection has also been used. However, such loss of signal techniques has been typically implemented in bipolar technologies. Their implementation in CMOS technologies is difficult. Since it may be desirable to implement various designs in CMOS from cost and ease of manufacturing as well as for power and performance reasons, it would be desirable to have a loss of signal approach that could be implemented in CMOS.
One aspect of detecting a loss of signal condition is to provide an indication of the existence of such a condition. It would be desirable to provide improvements in supplying that loss of signal indication.
Accordingly, the invention relates to utilization of hysteresis in determining whether a loss of signal condition exists for an input data stream. The use of hysteresis prevents the indication of a loss of signal condition from changing too frequently when the signal strength of the input data stream is close to the signal strength threshold level. The signal strength threshold level is determined according to a supplied loss of signal (LOS) threshold level. The LOS threshold level may be supplied, e.g., on an input terminal of the integrated circuit. For certain LOS threshold levels, hysteresis proportional to the signal strength threshold level may be sufficient. In such circumstances, e.g., the hysteresis utilized in deasserting a loss of signal indication is 3 db of the signal strength threshold. Thus, for example, a 20 mV peak-to-peak signal strength level for assertion would have a 30 mV peak-to-peak level for deassertion. However, at low signal strength thresholds, e.g., 6 mV, 3 db of hysteresis may not be sufficient given the magnitude of noise and other factors. Accordingly, a fixed amount of hysteresis is used for low signal strength thresholds in order to ensure-that the hysteresis level is sufficient.
In one embodiment a method is provided for determining whether a loss of signal condition exists for an input data stream according to a signal strength threshold level. The signal strength threshold level is determined according to a supplied loss of signal (LOS) threshold level. The method uses hysteresis for the signal strength threshold level that is proportional to the LOS threshold level when the LOS threshold level is above a predetermined level and uses fixed hysteresis for the signal strength threshold level when the LOS threshold level is below the predetermined level. The hysteresis provides a signal strength threshold level that has a greater magnitude on deassertion of a loss of signal indication than on assertion of the loss of signal indication. In one embodiment the fixed hysteresis amount is provided digitally.
In another embodiment an integrated circuit is provided that includes a first hysteresis circuit coupled to receive a loss of signal (LOS) threshold indication and to supply first and second loss of signal threshold (LOS) signals, the first LOS threshold signal threshold signal being proportionally larger than the second LOS threshold signal, thus providing hysteresis in proportion to the LOS threshold indication. A second hysteresis circuit provides a signal with a fixed hysteresis amount relative to the LOS threshold indication. A control circuit selects either the hysteresis in proportion to the LOS signal or the fixed hysteresis based on the level of the LOS threshold indication.
In still another embodiment, an integrated circuit includes a hysteresis mode circuit coupled to compare a threshold signal indicative of a threshold level to a predetermined value and to indicate a first hysteresis mode when the threshold signal is above the predetermined value and to indicate a second hysteresis mode when the threshold signal is below the predetermined value. A first hysteresis circuit supplies hysteresis proportional to the threshold level in the first hysteresis mode. A second hysteresis circuit supplies fixed hysteresis with respect to the threshold level in the second hysteresis mode.

Use of dual hysteresis modes in determining a loss of signal output indication