text
stringlengths 2
806k
| meta
dict |
|---|---|
1. Field of the Invention
The present invention relates to a robot control apparatus, and more particularly, to a robot control apparatus having a backward operation function for operating a robot to retrace a history of program execution.
2. Description of Related Art
A robot control apparatus has a function called a backward operation function as one of general functions thereof. This function of control is in a contrast to a forward operation function for operating a robot by reading an operation program forward, and is used for operating a robot to retrace the forward operation.
For example, the backward operation function is used when it is necessary to return the robot to an intermediate position or an initial position on a taught path so as to confirm the taught path or modify taught positions in a teaching operation, or when it is necessary to retract the robot which has been interfered and stopped in emergency from the interfered position.
The conventional backward operation function is, however, associated with the functional limitations mentioned below.
(1) In the backward operation, only motion commands are executed, and no consideration is given to motions involving input/output of external signals. For example, when the backward operation function is activated with respect to a forward operation including a closing (or an opening) action of a hand or a spot gun by an output signal to outside, an opening (or a closing) action to return the hand or the spot gun to the original state is not performed.
It is therefore necessary for an operator to separately carry out an operation for returning (opening or closing) the hand or the spot gun in the middle of the backward operation. If the operator omits to perform the returning operation or the returning motion is incomplete. (e.g, the hand or the spot gun is half-open), an interference may possibly be caused.
(2) If a branch command is executed during a forward operation, a backward operation which does not exactly correspond to the execution history is performed. Namely, according to the conventional backward operation function, a set of commands written in the operation program for the forward operation are simply executed in reverse order. Accordingly, in the case where the backward operation function is activated after a branch command is executed during a forward operation, a command that was skipped because of the branch command and was actually not executed (command which is not in the forward operation history) is executed during the backward operation.
The robot can therefore move to a position unexpected to the operator during the backward operation. To avoid this, the operator has to suspend the backward operation at a position immediately following the branch command, manually move the robot to a position immediately preceding the branch command, and then to restart the backward operation, thus requiring complicated operation.
(3) It is not possible to teach a backward mode executable program which is prepared specially for backward operation to be executed only during backward operation, and thus to start/execute such a backward mode executable program at a predetermined stage in the process of backward operation. For example, it is difficult to cause the robot to automatically take a "roundabout course from a certain robot position to the next robot position (immediately preceding position) via another robot position" only during backward operation.
(4) Similarly, it is not possible to teach a command to be executed only during backward operation (hereinafter referred to as backward mode dedicated command), and thus to execute such a backward mode dedicated command at a predetermined stage in the process of backward operation. For example, it is difficult to cause the robot to output a predetermined signal to the outside before the movement thereof from a certain robot position to the next robot position (immediately preceding position) only during backward operation.
(5) In connection with the problem that motions involving the input/output of external signals are not taken account of during backward operation, the output states of commands (hereinafter referred to as I/O commands) that dominate over the states of external devices during backward operation can not be selectively specified (e.g., specification of hand open state) at liberty.
(6) Since motions involving computation of register values are also not taken into account during backward operation, backward operation entailing restoration of register values cannot be executed. | {
"pile_set_name": "USPTO Backgrounds"
} |
Golf devices combining a number of tools into a single package are known in the prior art. For example, U.S. Design Patents 247,790 and 331,090 to Jackson and Cellura, respectively, are ornamental designs for combination golf ball marker and divot replacement devices. U.S. Pat. No. 5,110,123 to Larson describes a combined divot repair and ball marker golf device wherein two ball markers are constructed to be joined together and hold the divot repair portion between the joined markers. U.S. Pat. No. 5,393,052 to Kennedy describes a divot repair and ball marker device retaining a ball marker in the body of the device using gravity and U.S. Pat. No. 5,529,299 to Bellagamba describes a divot repair and ball marker device retaining a ball marker in the body of the device using a natural pressure from a slight expansion of a supporting slot holding the marker. U.S. Pat. No. 6,022,280 to Arenburg et al., U.S. Pat. No. 6,033,322 to England, and U.S. Pat. No. 6,514,159 to Hendren describe golf devices combining divot repair and ball maker retention capabilities wherein the ball marker is retained using magnetism.
With the exception of the '123 patent to Larson in which two ball markers are combined to form the marker retention device, each of the above combination golf devices include an elongated body having a pair of prongs at one end for use in divot repair connected to a ball marker retention mechanism at the other end. The devices are generally flat and small enough to be carried in a person's hand or fit in a shirt or pant pocket. The body is generally flat and includes a front and rear face connected by a narrower side wall.
One problem associated with prior approaches is a lack of positive retention force on golf ball markers being held by a golfer. Typically, golfers use a small, and relatively flat disc-shaped device to mark a golf ball location during game play. The ball marker is small in order to minimize the possibility of contact with another golfer's ball in motion. The ball marker is relatively flat to minimize the amount of impact to the path of another golfer's ball if contact occurs. Without a retaining force holding the marker in place, the marker is likely to slide out or otherwise become detached from a holder necessitating delay of game play until a suitable alternative may be found and likely agitating the golfer due to losing a particular marker. With respect to the '052 patent to Kennedy, the only marker retaining force is gravity; the marker will fall out if the device is upended. With respect to the '090, '280, '322, and '159 patents, it is likely that the marker will be forced out of the retention mechanism by inadvertent application of force to the backside of the marker while installed in the device.
Another problem associated with prior approaches is a lack of feedback to the golfer upon insertion of the ball marker in the ball marker retention mechanism. Under previous approaches, the golfer must look at the golf device in order to be certain the marker is retained therein.
Further, with respect to the '052 patent to Kennedy, the golfer is not assured of ball marker retention in the device without careful handling of the device because if the device is turned upside down, the ball marker will fall out of the c-shaped recess. With respect to the '299 patent to Bellagamba, the golfer is not assured of ball marker retention in the device as there is no indication provided by the device to the golfer that sufficient pressure has been applied to wedge the marker in the device. Further problematically, over time it is possible that even a tightly wedged marker in the device according to the '299 patent will work free and fall out of the device.
With respect to the magnetic-based retaining mechanism (used in the '280 patent to Arenburg et al, the '322 patent to England, and the '159 patent to Hendren), the above problem related to providing feedback to the golfer applies, as well. That is, even if the golfer hears a click sound indicating contact between the ball marker and the magnetic portion of the marker retention mechanism, there is no assurance that the marker is properly seated in the retention mechanism, thereby necessitating another time-consuming visual check of the device by the golfer.
There is a need in the art for a positive ball marker retention mechanism. Further, there is a need in the art for such a positive retention mechanism providing a feedback to a golfer indicating retention of the ball marker.
Additionally, because of the small size of the device, golfers are prone to dropping or otherwise losing the device. Loss of the device and attached ball marker involves agitation of the golfer and distraction during game play. Further, time is lost and greater distraction arises when the golfer casts about for a suitable replacement for, at a minimum, the ball marker. It would be beneficial to enable the golfer to attach or clip the device to the golfer's garments or golf bag for quick and easy access during game play.
Due to the size and need for ready access to such frequently used golf devices, there is a need in the art for a mechanism for attaching the device to other accessories or to a golfer's garments for quick access during game play.
Further, it is sometimes necessary to adjust, e.g. tighten or loosen, golf shoe spikes during the course of game play. It would be beneficial to provide a mechanism for adjusting golf spikes without requiring the golfer to carry a separate tool. | {
"pile_set_name": "USPTO Backgrounds"
} |
The liquid ejecting apparatus is provided with a liquid ejecting head and is an apparatus which ejects (discharges) various types of liquid from the liquid ejecting head. Examples of the liquid ejecting apparatus include image recording apparatuses such as an ink jet printer (referred to below simply as a printer) or an ink jet plotter; however, recently, the invention has been applied to various types of manufacturing apparatuses which take advantage of the feature that it is possible to accurately land extremely small amounts of liquid at predetermined positions. For example, the invention is applied to display manufacturing apparatuses which manufacture color filters for liquid crystal displays or the like, electrode forming apparatuses which form electrodes for organic EL (Electro Luminescence) displays, FEDs (field emission displays), or the like, and chip manufacturing apparatuses which manufacture biochips (biochemical elements). Then, ink is ejected in liquid form by a recording head for an image recording apparatus and a solution of each coloring material of R (Red), G (Green), and B (Blue) is ejected by a coloring material ejecting head for a display manufacturing apparatus. In addition, electrode material is ejected in liquid form by an electrode material ejecting head for an electrode forming apparatus and a solution of bio-organic matter is ejected by a bio-organic matter ejecting head for a chip manufacturing apparatus.
A printer which is one type of the liquid ejecting apparatus described above is provided with an ink jet recording head which is one type of liquid ejecting head (referred to below simply as a recording head). The recording head is configured so as to eject ink from a nozzle by generating pressure variations in ink inside a pressure chamber which is a part of a flow path of a head inner section by driving a pressure generating means such as a piezoelectric element by selectively applying a driving waveform (driving pulses) to the pressure generating means, and controlling the pressure variations.
The printer described above includes printers which are used in printing applications using a transfer textile printing system. Out of these transfer textile printing systems, one which is known as sublimation transfer textile printing is a method where a pattern or the like is printed by ejecting dye ink with respect to a transfer sheet using the printer and the pattern or the like which is printed on the transfer sheet is transferred to a transfer object (for example, a fabric made of polyester or the like). In more detail, by heating the transfer sheet and the transfer object in an overlaid state from both sides using heaters or the like, the coloring material of the dye ink on the side of the transfer sheet is sublimated by the heat to permeate to the transfer object side and subsequently transferred thereto by cooling (for example, refer to PTL 1 and PTL 2). According to such a system, textile printing is possible using a printer of the related art while suppressing costs.
In order to satisfy the requirements for inks for textile printing, the ink composition which is used in the transfer textile printing system described above (appropriately referred to below as ink for textile printing or simply as ink) includes a dispersion dye and a dispersing agent and a surfactant is also added in order to increase the permeation with respect to the transfer object by lowering the surface tension. Due to this, the ink composition has characteristics which are suitable for textile printing; however, there is a tendency for the surface tension of the ink for textile printing to be low in comparison with aqueous inks which are typically used in the printers described above. | {
"pile_set_name": "USPTO Backgrounds"
} |
Technology has been developed to enable efficient manufacture of electrical articles, such as power accessories, using a thermoplastic molding approach followed by an off-mold, latent cure (as opposed to standard in-mold vulcanization). Many design variations exist, but generally these articles comprise three-layers, i.e., (a) an inner semi-conductive sleeve referred to as the faraday cage, (b) an outer semi-conductive layer referred to as the jacket, and (c) a thick layer in between the two semi-conductive (a) and (b) layers, this thick layer made of an electrically insulating material and referred to as the insulation layer.
The new technology allows for the article to be molded in a standard thermoplastic injection molding process, and then cured off-mold at ambient conditions. Since not cured in the mold, one important requirement during the molding operation is to cool these thick articles enough to achieve geometrical integrity prior to demolding. The molding cycle is thus controlled by the efficiency of cooling the article inside the mold and achieving appropriate green strength for demolding. For this to work, the operation typically uses a chilled mold, one that is maintained below the melting temperature of the polymer(s) from which the article is made. This is very different from conventional in-mold vulcanization in which the material is injected and cured in a high temperature mold.
This off-mold cure method poses unique challenges including material solidification in undesired location, air entrapment, etc., which can results in article defects. In addition, given the typically elastomeric nature of the materials used, issues exist regarding layer deformation during injection and these, in turn, can lead to unacceptable article quality. This invention pertains to a molding method to solve the problem and enable the production of defect-free parts. | {
"pile_set_name": "USPTO Backgrounds"
} |
Field of the Invention
The present invention relates to a semiconductor device, and particularly to a semiconductor device that includes a duty correction circuit for adjusting a duty ratio of a clock signal,
Description of Related Art
The type called DDR (Double Data Rate) is the mainstream of DRAM (Dynamic Random Access Memory), which is a typical semiconductor memory device. The DDR-type DRAM is designed to input or output data in synchronization with both rising and falling edges of the clock signal. Therefore, the duty ratio of the clock signal needs to be precisely kept at 50%. For that purpose, a duty correction circuit is frequently used (See Japanese Patent Application Laid-Open No. 2008-210436).
The duty correction circuit is usually incorporated into a DLL (Delay Locked Loop) circuit that controls the phase of the clock signal. The DLL circuit includes a delay line that delays the clock signal. The duty ratio of the clock signal that has passed through the delay line is detected by a duty cycle detector, and the results thereof are fed back to the duty correction circuit, which then adjust the duty ratio of the clock signal.
However, the delay line has a relatively large amount of inherent delay. Therefore, the loop length of a feedback loop consisting of the duty correction circuit and the duty cycle-detector is relatively long. This leads to a decrease in feedback responsiveness in duty-control. The problem is that it takes a long time to reach a desired duty ratio. | {
"pile_set_name": "USPTO Backgrounds"
} |
In the past, telephone systems have been provided having an automatic call distributor (ACD). In one form, the ACD has a reporting system with output devices for supplying reports and information to the user. When the software is being developed for the reporting system, it is necessary to obtain information from the ACD in order to test and debug the program for the reporting system. However, it is difficult to control the ACD such that it supplies the desired data type and data rate for checking the software of the reporting system. | {
"pile_set_name": "USPTO Backgrounds"
} |
Users generally interact with computing devices through graphical user interfaces, which can display relevant content to users in a user-friendly, graphical manner. A graphical user interface is bounded by aspects of the computing device on which it is presented. For example, a graphical user interface can be limited to a virtual window or other bounding space provided for a software application underlying the graphical user interface.
In some instances, the size of the space provided to a graphical user interface restricts the amount of content that can be presented to a user. To handle these instances, software applications may limit the amount of content displayed to the user in a graphical user interface to an amount that can be squeezed into an expected size of available space. Alternatively, some software applications include scroll bars, so that the user can scroll between portions of the graphical user interface when the entire graphical user interface does not fit into the available space. Unfortunately, these partial solutions do not enable the user to control what is displayed and do not adequately take advantage of available space when that space is relatively large.
Therefore, there is a need for a graphical user interface that can effectively adapt to the space provided for displaying content. In an exemplary embodiment, such a graphical user interface can make all contents available, even when the space provided is relatively small, by allowing a user to easily switch between available contents. It would be further desirable, when that available space increases, for a graphical user interface to expand and provide dedicated display areas for content that would not have dedicated space if the total available space were relatively small. It is to embodiments of such graphical user interfaces that various embodiments of the present invention are directed. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a floppy disc drive apparatus, and more particularly to a board configuration or a substrate structure of the control circuit section for the floppy disc drive apparatus.
2. Description of the Prior Art
There is known a control circuit section for floppy disc drive apparatus that comprises an upper printed wiring board mounting thereon a circuit adapted to process signals in association with a head mechanism and a circuit adapted to drive a stepping motor, a lower printed wiring board mounting thereon an overall control circuit, a card edge terminal and a power socket, and a drive motor board mounting thereon a drive motor driving circuit. (Japanese Patent Laid-Open specification No. 59-90274).
With such a configuration or structure, the printed wiring boards separated for separate functions are less subject to adverse effects due to mutual interference. But the increased number of printed wiring boards results in an increase of the number of connection lead wires between the printed wiring boards and the number of parts, thereby reducing noise resistance, reliability as well as the assembly efficiency. | {
"pile_set_name": "USPTO Backgrounds"
} |
Most business professionals today spend between 20% and 50% of their working time using e-mail: reading, ordering, sorting, ‘re-contextualizing’ fragmented information and of course writing emails. Use of e-mail is increasing due to trends of globalization such as distribution of organizational divisions and outsourcing.
When a user receives an email message and hits a reply button to type a response, an initial message is copied to a mail window buffer, and the user can edit the initial message. For example, the user may delete everything but a single paragraph to which the user wants to respond. The user may then send the response to the sender of the initial message, as well as some other users who were not the recipients of the initial message. Currently, the users who join the email thread late have no way of knowing how the initial message looked like in its original form. In particular, if the initial message was partially erased, they cannot view the erased portions, and even if the initial message looks complete, they cannot be certain that it has not been modified by other recipients. | {
"pile_set_name": "USPTO Backgrounds"
} |
Prior art solenoid valves are often used to control the flow of hydraulic fluid in automotive vehicle transmission systems. A traditional variable bleed solenoid valve regulates pressure by reducing pressure in a control volume through a variable leak path (exhaust) to a pressure sump. The amount of leakage is inversely proportional to the pressure in the control portion of the valve. This leakage is controlled by a variable orifice, which typically takes the form of a sealing member (flat, conical, ball, or otherwise) that is moved in relation to a fixed annular sealing surface that surrounds a fixed orifice. When the sealing member is in contact with the sealing surface, the leakage approaches zero, and the pressure in the control volume is at its peak value. When the sealing member is moved away from the sealing surface, the leakage increases, and the pressure in the control volume decreases at a rate that is a function of the swept area of the shortest distance between sealing member and seat. The leakage can be significant when multiplied by the number of solenoid devices located within the transmission. Minimizing the leakage of each of the individual solenoid components is desirable in order to minimize the capacity requirement of the hydraulic pump that generates the system pressure and to improve the efficiency of the transmission. A low leak variable bleed solenoid by design minimizes this leakage. Minimal leakage to sump is achieved by integrating a supply shut off (secondary) valve in series with the exhaust bleed (primary) valve. These two valves are actuated simultaneously. When the exhaust bleed (primary) valve is fully open to achieve minimum control volume pressure, the supply shut off (secondary) valve is fully closed to prevent fluid leakage to sump through the control volume. As the exhaust bleed (primary) valve is closed to increase pressure in the control volume, the supply shut off (secondary) valve is opened to allow fluid to enter into the control volume. At maximum pressure in the control volume, the exhaust bleed (primary) valve is fully closed and the supply shut off (secondary) valve is fully open.
A disadvantage of known low leak variable bleed solenoid valves is that the addition of a supply shut off valve in close proximity to the exhaust bleed valve complicates the construction of the solenoid valve. Additional components that re-direct flow often have complex geometries that are difficult and expensive to manufacture. Another disadvantage is that many of the known low leak variable bleed solenoid valves are more sensitive to fluctuations in supply pressure and temperature as they have hydraulic areas acted upon by supply pressure that are not balanced. The invention described herein differs from the prior art by utilizing simpler valve and flow geometry, which also has the advantage of minimizing supply pressure feedback area. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to devices used on reconfigurable chips for loading data or configuration. Reconfigurable chips typically load data and configuration from an off-chip memory. Especially when reconfigurable chips are used for reconfigurable computing, the loading of the data and configuration from the off-chip memory can take a significant amount of time, slowing the operation of the reconfigurable chip.
It is desired to have an improved loading plane for use on a reconfigurable chip.
One embodiment of the present invention comprises a loading plane which includes a number of background bit storage units associated with foreground bit storage units. At least one of the background units receives a data bit from off-chip memory. This unit can selectively supply the background data bit to a foreground unit. Additionally, at least one additional background unit receives a data bit from an on-chip source, the additional background unit also adapted to selectively supply the background data bit to the foreground unit.
In this way, both data from off-chip and data derived on-chip can be provided to the foreground unit. In a preferred embodiment, the above units are combined into a register block. This register block is preferably within a data path unit. By having background units, the system can operate on the current data loaded in the foreground, while still loading data for the next operation into the background. By having an additional background unit able to load from on-chip, additional flexibility is gained in the operation of the reconfigurable chip. | {
"pile_set_name": "USPTO Backgrounds"
} |
Golf clubs take various forms, for example a wood, a hybrid, an iron, a wedge, or a putter, and these clubs generally differ in head shape and design (e.g., the difference between a wood and an iron), club head material(s), shaft material(s), club length, and club loft.
Woods and hybrids generally have a longer shaft and lower loft than irons and wedges. Thus, a golf ball that is struck with a wood or a hybrid generally travels a greater distance than a golf ball struck with an iron or a wedge. While a longer shaft and a lower loft provide increased golf ball travel distance, this combination also results in less forgiveness. The longer shaft requires a golfer to stand farther away from the golf ball at address. This leads to greater difficulty during the golf swing to return the club head squarely to impact the golf ball. A golf club that is slightly open or slightly closed at impact results in reduced accuracy as the golf ball is not launched on the desired target line. Further, the higher swing speeds from the longer length shaft can lead to greater difficulty in making consistent contact with the center or “sweet spot” of the golf club face. Off-center contact can lead to imparting increased side spin on the golf ball. At reduced lofts of woods and hybrids, less back spin is imparted on the golf ball at impact, further exacerbating imparted side spin and leading to undesirable hooks or slices, which further decrease accuracy.
To improve directional forgiveness, golf club manufacturers have made efforts to increase the moment of inertia of a golf club at impact. The moment of inertia (or “MOI”) is a measure of a body's resistance to angular acceleration, or twisting. The higher the MOI of a golf club head, the more the golf club head resists twisting at impact, improving golf ball accuracy, especially on off-center contact (or mishits). In addition, the increased stability of a higher MOI golf club head results in a golf ball losing less ball speed on off-center contact due to reduced energy loss associated with reduced twisting. A higher MOI of a golf club head further increases consistency in spin rate and launch angle of a golf ball on off-center contact.
While woods and hybrids have a variety of known designs, there is a need for enhancing directional forgiveness (e.g., a reduction in side-to-side variation) to improve accuracy, especially on off-center hits (e.g., contact of the golf ball with a location on the golf club face other than the sweet spot). | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates generally to virtual machines and more particularly to establishing a protected virtual machine in a hypervisor controlled system.
A lifecycle of a virtual machine, also known as a guest, can vary depending on specific operations the virtual machine is assigned to perform. Prior to virtual machines, physical servers used to perform dedicated tasks without having the ability to shuffle tasks between other physical servers for efficiency purposes. Typically, a virtual machine is prepared for tasks with the same operating system (OS), applications, and configurations and stored in a physical storage until the virtual machine can execute the task. Once the task is sent to a physical server supporting the virtual machine, the physical server can perform the task assigned to the virtual machine, the physical server can shutdown upon completion, and revert back to the physical storage. As a result, virtual machines are utilized like physical servers but with a distribution of tasks to decrease operation frequency. Typically, a service provider manages virtual machines, where a client utilizing the virtual machines has to trust that the integrity of the virtual machines has not been compromised. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates generally to video games and more particularly, it relates to an improved three-dimensional, texture mapping display system for displaying three-dimensional projected polygons with texture maps on a two-dimensional raster display screen. In particular, the display system is adapted for use with video games to allow real-time animation of video game scenes with textured plane surfaces in a time period substantially less than that required in traditional display systems of this general type.
In the prior art display systems for displaying three-dimensional representations of images on a two-dimensional raster display screen of a cathode ray tube (CRT), it is generally desired to provide a mechanism for generating realistically textured surfaces in the image so that a general dimensional representational effect will be produced. In such conventional display systems for providing such an effect, this is achieved by some type of texture surface generator involving rather lengthy and complex arithmetic algorithms or mathematical computations to be performed, such as multiplication, division, addition, subtraction, and/or trigonometric function calculations.
Therefore, these prior art systems have a major disadvantage in that a user had to wait a considerable amount of time before the image could be displayed on the screen. Not only are the prior art display systems very time-consuming, the hardware circuits necessary to implement the various mathematical computations is very expensive.
Accordingly, it would therefore be desirable to provide an improved three-dimensional, texture mapping display system for displaying three-dimensional projected polygons with texture maps on a two-dimensional raster display screen which uses simplified algorithms involving only addition and subtraction operations and thus rendering a high operational speed. | {
"pile_set_name": "USPTO Backgrounds"
} |
JP 609 4244-A2 discloses a microwave oven and a specifically designed cooking vessel, which has been provided with thermo-colour fields arranged around a periphery of the round vessel. A reflection type light sensor is provided for detecting a change of colour of said thermo-colour. By means of this feedback information a heating operation of a beverage or foodstuff in said container may be controlled.
GB 20 52 731-A discloses in general terms a set-up of a temperature responsive device in which light from a light source is directed towards a sensor of which the reflective characteristics changes with temperature. Reflected light from the sensor and received by a receiver provides information about such changes by temperature.
U.S. Pat. No. 5,285,041 discloses an automated food vending system comprising a microwave oven provided with a code reader for reading a bar code printed on a package.
Navy Technical Disclosure Bulletin, vol.10, no.1, Sep. 1, 1984, Arlington, Va. USA, pages 75-79,XP002006334 T. R. Odgen "Liquid Crystal Temperature Measurement Device" discloses a measurement apparatus for detecting the temperature of surfaces coated with thermographic liquid crystals, which can operate in water.
U.S. Pat. No. 4,933,525 discloses a microwaveable container provided with a plurality of liquid crystal film display devices which change colour in response to a preset temperature.
A general problem when using optical sensing/reading devices of the actual type is to establish a sustainable security in reading. Mainly this may be referred to the fact that the information carrying differences in the received reflected light may be small and therefore difficult to detect. Possibly this may be solved by the use of a more complicated light receiver including means for a deeper analysis of the spectrum of the received light, changing when the thermo sensitive surface changes colour at a temperature increase, for example. However, this further complication and increased costs therefore are highly undesirable in a consumer type equipment like a microwave oven. Another, related problem is that an accurate positioning of the cooking vessel or container, more specifically the sensor or sensors thereof, is required in relation to the light source and light receiver in order to obtain the symmetrical arrangements disclosed in said references, i.e. transmitting a light beam of a given angular off-set in relation to a perpendicular of the sensor surface and receiving a reflected beam of the same but opposite angular off-set.
In order to maintain the reflective characteristic of the sensor surface it is generally necessary to provide the sensor surface with a transparent cover layer or coating. In case the thermo-colour has been realized by means of a liquid crystal, such a transparent cover is a pure necessity. The use of this cover has the consequence that the amount of light in the surface reflected light beam will substantially not change with changes of the underlying thermo-colour. This problem is specifically focused in case of disposable type containers or packages regularly having a coating of this type. Moreover, use of packages or containers of this type further aggravates said sensor positioning problem, because the container wall and thereby the sensor carrying surface may bulge, thereby disturbing the reception of a symmetrically reflected reading beam.
Another problem in case of disposable containers is that non-approved packages may wrongly be interpreted as approved ones, which may lead to an unintended start of the heating progress with consequent risks for the user. Still another user risk may occur if a user inadvertently places an empty approved-type container in the oven. Within seconds this may lead to development of smoke and open fire.
These problems have neither been discussed in the referenced prior art, nor solved thereby. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to the field of electronic design automation (EDA). More specifically, the present invention relates to integrated circuit modeling having timing information associated therewith for use with EDA systems for the design of integrated circuit devices.
2. Related Art
Rapid growth in the complexity of modern electronic circuits has forced electronic circuit designers to rely upon computer programs to assist and automate most steps of the integrated circuit design process. Typical circuits today contain hundreds of thousands or millions of individual pieces or xe2x80x9ccells.xe2x80x9d These designs are much too large for a circuit designer or even an engineering team of designers to manage effectively manually. To automate the design and fabrication of integrated circuit devices, the field of electronic design automation (EDA) has been developed which uses computer aided design (CAD) tools and systems.
Typically, CAD tools function in part by decomposing the overall desired behavior of the integrated circuit into simpler functions which can be represented as functional cells by the CAD tool. The CAD tool generates netlists including cells, logic gates and connections between them which perform the desired circuit behavior. Netlists can represent the integrated circuit in different levels of abstraction depending on the CAD function being performed, such as the behavior level, the structural level and the gate level. However, the high level design (HDL) description is typically the starting point for CAD tools because the HDL description file describes the behavior of the integrated circuit.
FIG. 1 illustrates a prior art EDA process 100. An HDL description 101 of an integrated circuit is received by a logic synthesis process 102. Process 102 first generates a technology independent netlist (including cells) based on the HDL description 101 and then generates a technology dependent netlist (including gates) based on a specified process technology library 103. The technology specific library 103 includes specific information regarding the cells of the selected process technology.
Optimization processes 104 are then applied to the technology dependent netlist so that specified design constraints 105 (e.g., area constraints and timing, power and other performance related constraints) can be maintained in the resultant design. Optimization 104 is the process of mapping one representation of functionality for an electronic circuit to another. The representation may be in terms of a circuit netlist (an abstract interconnection of electronic components), a circuit layout (an interconnection of components and their associated physical placement and wiring), or an abstract functional description which simply describes the function the circuit should perform without fully specifying circuit details. In general, optimization attempts to improve some aspect of the functionality of a circuit, e.g., its speed, its size, its power consumption, or some other circuit parameter. The goal of the optimization processes 104 is to select a functionally equivalent cell or group of cells that can be used to replace an existing cell where the replacement reduces the area of the integrated circuit or improves its performance (e.g., speed, power dissipation, etc.). The xe2x80x9cDesign Compiler,xe2x80x9d which is commercially available from Synopsys, Inc. of Mountain View, Calif., is an example of an automated circuit optimizer 104.
Circuit simulation 106 of FIG. 1 is used to determine if the modifications performed by the optimization process satisfy the given design constraints 105. Circuit simulation 106 can also be used to test if the netlist operates in the proper logical manner. At step 108 of FIG. 1, if the netlist satisfies the given design constraints 105 and logical simulation verifies, it is used to fabricate a physical integrated circuit device. Step 108 typically includes automatic coarse and fine placement processes where the cells of the netlist are spatially placed in the substrate area. Then, interconnections between the cells are routed in an automatic routing process.
The steps outlined in process 100 can be very process intensive thereby consuming large amounts of computer time and computer resources. For this reason, it is typical for large integrated circuit designs to be broken down into separate circuit blocks with each block independently being subjected to one or more of the steps of process 100. xe2x80x9cCharacterizationxe2x80x9d refers to the process of setting up distinct circuit blocks of a large circuit design to be optimized independently, outside of the whole integrated circuit design. For instance, assume a circuit design, E, contains circuit blocks A, B, C, and D. Circuit E has specified timing constraints and timing exceptions. Characterization automatically generates timing constraints and exceptions which are appropriate for the optimization of blocks A, B, C and D, independently. When optimizing the blocks using characterization, the optimization tool 104 (FIG. 1) need only load and process one block at a time. This decreases the demand of the tool on the computer resources. After the blocks have been optimized, they are then re-assembled back into circuit E. One example of the characterization described above is the xe2x80x9ccharacterizexe2x80x9d command found in the above referenced Design Compiler tool from Synopsys, Inc. of Mountain View, Calif.
Modeling is another tool used in EDA processes to reduce the demand on computer resources when designing integrated circuits. Modeling represents a circuit block in a more compact form so that it requires less computer memory resources to represent and also so that it requires less processor time to process. Usually, models achieve their smaller memory requirements by omitting details about the original block in the model. Because details are omitted from them, models cannot be used as a universal replacement for a circuit block. Usually models can only be used for very specific purposes. Prior art models contain a limited amount of information about the circuit block they replace. For instance, prior art models contain the circuit block size, the name and physical position of the pins of the circuit block, the pin""s imposed electrical capacitance, the pin""s imposed electrical current (drive), the arrival time at a circuit block""s output and the required time at a circuit block""s input. Although useful for some applications, the above described models do not model timing exceptions and therefore these models are not appropriate for use in general applications such circuit optimization.
The xe2x80x9cmodelxe2x80x9d command of the Design Compiler from Synopsys, Inc. and the xe2x80x9cextract_modelxe2x80x9d command of PrimeTime from Synopsys, Inc. create models from circuit blocks. U.S. Pat. No. 5,790,830, issued Aug. 4, 1998, by Russell B. Segal and entitled xe2x80x9cExtracting Accurate and Efficient Timing Models of Latch-Based Designsxe2x80x9d describes one form of modeling. These models can be used in a circuit to evaluate the timing. These models are appropriate for replacing prepackaged circuit blocks which are self contained. However, these models are not appropriate to general applications such as use in optimization because, among other shortcomings, they do not model timing exceptions.
Accordingly, what is needed is a method and system for providing a more effective circuit block model. What is needed further is a more effective and efficient optimization process. The present invention provides these advantages. These and other advantages of the present invention not specifically mentioned above will become clear within discussions of the present invention presented herein.
Embodiments of the present invention as described herein are drawn to solutions to problems posed by the optimization and analysis of large circuits. When circuits get large, they place a large burden on optimization and analysis tools which try to process them. In particular, the tools require increasing large amounts of computer memory and processor time to process the circuits. Often, computers are not large or fast enough to handle the task. Some technologies have been developed in the past to solve this problem, but they do not provide a complete solution. The embodiments of the present invention provide a more complete solution to the above problems.
Integrated circuit models are described herein having associated timing and tag information therewith for use with electronic design automation to effectively model timing exception information. The present invention includes a circuit block model which allows automated circuit optimization to be performed on extremely large circuits without the need to load all of the details of the circuit into computer memory. The circuit models of the present invention effectively model timing information including timing exception information. The model of the present invention is associated with command data structure, e.g., composed of textual commands (in one implementation), that describes arrival and required tags (which model exceptions) that are associated with the boundary of the original circuit block that is modeled. Specifically, for the input pins of a circuit to be modeled, the present invention writes out a command defining each unique required tag associated with an input pin and also writes out commands associating each required tag with its input pin. For the output pins of a circuit to be modeled, the present invention writes out a command defining each unique arrival tag associated with an output pin and also writes out commands associating each arrival tag with its output pin. The tag, arrival and required times are then associated with the model, along with other information. By saving the pertinent arrival and required tags (as associated times) at the circuit block boundary, timing exceptions are thereby effectively and efficiently modeled using the present invention.
The present invention also includes various circuit optimization processes (e.g., block and top optimization, bottle optimization and in-context optimization) that utilize the above described circuit model with exception information. These circuit optimizations can be used for incremental optimization of a large circuit. Optimizations using the above circuit models can be performed very efficiently and effectively and are particularly well suited for large integrated circuit designs.
Specifically, embodiments of the present invention include a computer readable memory unit of a computer controlled EDA system having stored therein a circuit model for representing a circuit block of an integrated circuit design, the circuit model comprising: a first set of commands which are arrival tag definitions and required tag definitions corresponding to timing exception paths which cross the boundary of the circuit block; a second set of commands defining associations between respective input pins of the circuit model and required tag values defined for the respective input pins, wherein the required tag values reference the required tag definitions of the first set of commands; and a third set of commands defining associations between respective output pins of the circuit model and arrival tag values defined for the respective output pins, wherein the arrival tag values reference the arrival tag definitions of the first set of commands. Embodiments include the above and wherein the first, second and third set of commands of the circuit model are textual commands. Embodiments include the above and wherein the arrival tag definitions and the required tag definitions are based on defined virtual clocks.
Embodiments also include a method of creating a circuit model representing a circuit block of an integrated circuit design, the method comprising the steps of: generating and storing a shell by copying a portion of the circuit block; generating and storing first commands which are arrival tag definitions and required tag definitions corresponding to timing exception paths which cross the boundary of the circuit block; generating and storing second commands that define associations between respective input pins of the circuit model and required tag values defined for the respective input pins, wherein the required tag values reference the required tag definitions of the first commands; and generating and storing third commands that define associations between respective output pins of the circuit model and arrival tag values defined for the respective output pins, wherein the arrival tag values reference the arrival tag definitions of the first commands; and creating the circuit model by associating the first, second and third commands with the shell. Embodiments include the above and wherein the first, second and third set of commands of the circuit model are textual commands. | {
"pile_set_name": "USPTO Backgrounds"
} |
Machines for inserting items such as sheets of paper into envelopes are known in the art. For example, Werner et al. (U.S. Pat. No. 6,164,046) discloses a mail inserter which has an envelope supply module and an insert material module disposed side-by-side from each other, mechanically linked by a table where a retrieved envelope is moved from the envelope supply module to the insertion station in a different direction. The mail inserter, as disclosed in Werner et al., is represented by a block diagram as shown in FIG. 1. As shown in FIG. 1, the mail inserter 1 has an insertion station 5 wherein insert material is inserted into a receiving envelope. The mail inserter 1 comprises an envelope supply module 10 to supply the envelopes and an insert material supply module 70 to supply the insert material. As disclosed in Werner et al., a typical insert material supply module has a plurality of feeders for separately releasing sheets of insert material onto a moving belt where the sheets of insert material are cumulated into stacks. The stacks of insert material are sequentially moved into the insertion station for insertion. From the envelope supply module 10, envelopes are retrieved one at a time by an envelope retrieval mechanism 20 and the retrieved envelope is moved toward the insertion station 5. Before reaching the insertion station 5, the flap of the retrieved envelope is opened by a flap opening mechanism 30. In the insertion station 5, the throat of the envelope is opened by a throat opening mechanism 40 so as to allow the insertion module 60 to move a pack of insert material into the receiving envelope. After the insertion is completed, the stuffed envelope is moved away from the insertion station 5. A flap closing section 50 is used to close the flap of the stuffed envelope. The closed envelope is then sealed and further processed.
As shown in FIG. 2, an envelope 90 has a flap 92. After the flap 92 is opened, a throat 98 is exposed. The throat 98 is formed by a front envelope panel 94 and a back envelope panel 96. After the flap is opened, the envelope 90 is moved to the insertion station along a direction 390. In the insertion station, the flap 92 of the envelope is typically held down by a mechanical means when the throat 98 is opened. The throat 98 can be opened by a number of different ways. For example, it can be opened by blowing a puff of air into the throat; or it can be opened by using one or more suction cups to pull up the back panel 96 of the envelope while holding down the front panel 94. Suction cups can be used to pull up the back panel 96 at two locations 42, for example. While the throat 98 of the envelope is opened, a pack of insert material 80 is moved along direction 380 into the envelope. Subsequently, the stuffed envelope 90′ is closed and sealed.
Jams may occur in a mail inserter in a number of places. For example, jams may occur in the insertion station when insert material crashes into the suction cups. If crush of the inserts happens late in the cycle, the envelope transport will try to move the envelope with inserts towards the flap closing section 50, pushing material against the suction cups in the direction of envelope motion. Jams may also occur in the insertion station when the just inserted envelope crushes against the previously inserted envelope jammed in the flap closing section 50. When the moving speed of the insert material is high a crash may damage the suction cups. The damage can be serious if the insert material is thick and heavy.
It is thus advantageous and desirable to provide a method and system to reduce the damages caused to the suction cups in a jam. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field
Embodiments relate to methods of forming semiconductor devices and, more particularly, to methods of forming variable resistive memory devices.
2. Description of the Related Art
Semiconductor devices can be, e.g., semiconductor memory devices and semiconductor logic devices. The semiconductor memory devices may store data. The semiconductor memory devices may be categorized as, e.g., volatile memory device and nonvolatile memory devices. Volatile memory devices may lose their stored data when their power supply is interrupted. Nonvolatile memory devices may retain their stored data even when their power supply is interrupted. The nonvolatile memory devices may include, e.g., programmable read only memory (PROM) devices, erasable PROM (EPROM) devices, electrical EPROM (EEPROM) devices and flash memory devices.
Semiconductor memory devices may also include, for example, ferroelectric random access memory (FRAM) devices, magnetic random access memory (MRAM) devices and phase-change random access memory (PRAM) devices. Memory cells may include a variable resistive material, which may have a characteristic that the electrical resistance of the material varies according to current or voltage applied thereto. Further, when included as part of a memory cell, the variable resistive material may retain its final electrical resistance even though the current and/or voltage supply is interrupted. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to high voltage vertical power transistors that are circuits vertically fabricated in a silicon wafer whose rear surface is connected to a high voltage. The invention is directed to MOS-type vertical power transistors or insulated-gate bipolar transistors (IGBT's), and more particuLarly applies to Smart Power switches, that are circuits including on a same silicon chip vertical power components and logic circuits for controlling such components.
2. Discussion of the Related Art
Power transistors are designed to withstand a predetermined forward voltage (for example, 400 volts). The application of a higher voltage to the circuit by the external circuit causes a breakdown of the device that can damage it. For example, the switching of an inductive load generates an overvoltage with a determined quantity of energy to be dissipated. Such over-voltage is applied to the power switch that is off, or is in a transient off state. One of the solutions to protect the transistor is to provide a signal onto its control electrode to briefly bring the transistor in a conductive state during a period long enough to dissipate the excess energy.
It is therefore desirable to provide a device that goes to conduction state for a value slightly lower than the breakdown voltage of the power transistor(s) in order to, for example, trigger the conduction of the transistors before their breakdown threshold, thus avoiding damage.
In the following description, power MOS transistors are always referred to. However, it is clear that the whole description also applies to IGBT's whose structure is substantially identical, except for the fact that they include on the side of the rear surface a layer having a conductivity opposite to the conductivity of the layer forming the rear surface of a power MOS transistor.
In order to better illustrate the problem that the invention aims at solving, FIG. 1 represents a cross-sectional view of an exemplary conventional dual structure including a vertical diffused MOS (VDMOS) transistor TP, two cells of which are represented. Such transistor is combined with logic circuits, including an N-channel MOS transistor TL of which is illustrated. The vertical MOS transistor is comprised of a large number, for example 10,000, of identical cells.
The structure is fabricated in a substrate O of a first conductivity type, for example of the N-type. A cell of the power MOS transistor TP includes a well 1 (1-1, 1-2) formed by a P-type diffusion in the substrate. In each well 1-1, 1-2 is formed an N.sup.+ -type annular diffusion region that constitutes an element of the power transistor source. Diffusions 2 are interconnected through a conductive layer 3 that is, for example, made of aluminum. The surface peripheral areas of regions 1 form a channel region 4 of the power transistor. Additionally, each well 1 generally includes a deeper and more highly doped central portion 5 (5-1, 5-2).
Each cell of the power MOS transistor TP includes a gate 6, formed above the surface peripheral areas by a polycrystalline silicon layer. Gate 6 is separated from substrate 1 by an oxide layer 7. All the gates 6 are interconnected.
The rear surface 10 of substrate 1 includes an highly doped layer 11 of the first conductivity type which is coated with a drain metallization 12.
The MOS transistor TL of the logic portion also includes a P-type well 14 region formed in the substrate. Well 14 includes two N.sup.+ -type areas, the first area forming source 15 and the second area forming the drain 16 of transistor TL. Transistor TL includes a gate 18 formed by a polycrystalline silicon layer above the well region. Gate 18 is separated from well 14 by an oxide layer 19. The diffused areas forming source 15 and drain 16 are connected to a conductive line labeled 20, 21, respectively. The conductive lines 20, 21 are for example of aluminum.
Conventionally, a P.sup.+ -type area 23 connected to a conductive layer 24 is also provided in well 14. Area 23 and the conductive layer 24 connect well 14 to ground.
Under normal operation, the metallization of the rear surface 12 is connected to a positive voltage, and the front surface metallizations 3 of the power transistor are connected to a voltage that is negative with respect to the positive voltage, for example, a voltage close to the ground voltage.
The problem to be solved is to avoid a switching on, due to breakdown, of the power transistor cells, i.e. due to an avalanche phenomenon of the junction between substrate O and the P-type wells of the transistor cells (1-1, 1-2, 5-2) when the drain voltage increases while the transistor is off. Such a switching on is undesirable because it may cause heating of this junction where the avalanche is generated due to excessive flow of current, and this heating can be destructive. It should be also noted, in the case of the represented integrated circuit including a logic portion, that an avalanche breakdown may occur at the junction between the substrate and the wells of the logic component cells. Conventionally, the structure is designed so that this latter junction breaks down after the junction of the power transistor cells.
An avalanche diode, having a triggering threshold lower than the threshold of the active cells of the power MOS transistor can be conventionally used, for example as illustrated in FIG. 2 which represents the power transistor TP with its drain terminal D (12), source terminal S (3) and gate terminal G (6). Transistor TP includes a reverse conduction diode 30 which corresponds to the junction between P-type well 5 and the N-type substrate 0 of the transistor TP. The reverse breakdown of this diode corresponds to the avalanche breakdown of the power transistor cell TP. An avalanche diode 31 can be connected between the drain and the gate and can be such that an avalanche voltage of diode 31 plus a forward voltage drop of a series diode 32 is less than the breakdown voltage of the power transistor and is therefore turned on before the power transistor enters the avalanche mode. The series diode 32 is used to avoid the derivation of normal gate control signals. The circuit of FIG. 2 is represented by way of example only because various alternative circuits for the triggering of a main transistor occurring after the triggering of a detection avalanche diode are known. It should be noted that, in most of these circuits, as illustrated in FIG. 2, the cathode of the avalanche diode is connected to the drain of the power transistor. This cathode or drain corresponds to the common terminal 12 of FIG. 1.
A different approach is described in the U.S. Pat. No. 5,136,349 in which each individual cell of a power MOS transistor is specifically designed so as to include a central avalanche diode that goes to avalanche mode shortly before the cells of the power transistor. Such structure has two drawbacks. The first drawback is that a new design of all the cells of a power MOS transistor is required, whereas, normally, the manufacturers of power MOS transistors have already developed optimized cells. This new design involves a major task that does not take advantage of prior developments already made by manufacturers. The second drawback is that major adjustment tasks are required to design the shape of the avalanche diode so that its triggering threshold is adequately determined with respect to the avalanche threshold of the power transistor cells. | {
"pile_set_name": "USPTO Backgrounds"
} |
Cell signaling via 3′-phosphorylated phosphoinositides has been implicated in a variety of cellular processes, e.g., malignant transformation, growth factor signaling, inflammation, and immunity (see Rameh et al., J. Biol. Chern., 274:8347-8350 (1999) for a review). The enzyme responsible for generating these phosphorylated signaling products is phosphatidylinositol 3-kinase (PI 3-kinase; PI3K). PI3K originally was identified as an activity associated with viral oncoproteins and growth factor receptor tyrosine kinases that phosphorylates phosphatidylinositol (PI) and its phosphorylated derivatives at the 3′-hydroxyl of the inositol ring (Panayotou et al., Trends Cell Biol 2:358-60 (1992)).
Levels of phosphatidylinositol-3,4,5-triphosphate (PIP3), the primary product of PI 3-kinase activation, increase upon treatment of cells with a variety of agonists. PI 3-kinase activation, therefore, is believed to be involved in a range of cellular responses including cell growth, differentiation, and apoptosis (Parker et al., Curr. Biol., 5:577-99 (1995); Yao et al., Science, 267:2003-05 (1995)). Though the downstream targets of phosphorylated lipids generated following PI 3-kinase activation have not been well characterized, emerging evidence suggests that pleckstrin-homology domain- and FYVE-finger domain-containing proteins are activated when binding to various phosphatidylinositol lipids (Sternmark et al., J. Cell. Sci., 112:4175-83 (1999); Lemmon et al., Trends Cell Biol., 7:237-42 (1997)). In vitro, some isoforms of protein kinase C (PKC) are directly activated by PIP3, and the PKC-related protein kinase, PKB, has been shown to be activated by PI 3-kinase (Burgering et al., Nature, 376:599-602 (1995)).
Presently, the PI 3-kinase enzyme family is divided into three classes based on their substrate specificities. Class I PI3Ks can phosphorylate phosphatidylinositol (PI), phosphatidylinositol-4-phosphate, and phosphatidylinositol-4,5-biphosphate (PIP2) to produce phosphatidylinositol-3-phosphate (PIP), phosphatidylinositol-3,4-biphosphate, and phosphatidylinositol-3,4,5-triphosphate, respectively. Class II PI3Ks phosphorylate PI and phosphatidylinositol-4-phosphate, whereas Class III PI3Ks can only phosphorylate PI.
The initial purification and molecular cloning of PI 3-kinase revealed that it was a heterodimer consisting of p85 and p110 subunits (Otsu et al., Cell, 65:91-104 (1991); Hiles et al., Cell, 70:419-29 (1992)). Since then, four distinct Class I PI3Ks have been identified, designated PI3K α, β, δ, and γ, each consisting of a distinct 110 kDa catalytic subunit and a regulatory subunit. More specifically, three of the catalytic subunits, i.e., p110α, p110β, and p110γ, each interact with the same regulatory subunit, i.e., p85, whereas p110γ interacts with a distinct p101 regulatory subunit. As described below, the patterns of expression of each of these PI3Ks in human cells and tissues also are distinct. Though a wealth of information has been accumulated on the cellular functions of PI 3-kinases in general, the roles played by the individual isoforms are largely unknown.
Cloning of bovine p110α has been described. This protein was identified as related to the Saccharomyces cerevisiae protein: Vps34p, a protein involved in vacuolar protein processing. The recombinant p110α product was also shown to associate with p85α, to yield a PI3K activity in transfected COS-1 cells. See Hiles et al., Cell, 70, 419-29 (1992).
The cloning of a second human p110 isoform, designated p110β, is described in Hu et al., Mol. Cell. Biol., 13:7677-88 (1993). This isoform is said to associate with p85 in cells, and to be ubiquitously expressed, as p110β mRNA has been found in numerous human and mouse tissues, as well as in human umbilical vein endothelial cells, Jurkat human leukemic T cells, 293 human embryonic kidney cells, mouse 3T3 fibroblasts, HeLa cells, and NBT2 rat bladder carcinoma cells. Such wide expression suggests that the p110β isoform is broadly important in signaling pathways.
Identification of the p110δ isoform of PI 3-kinase is described in Chantry et al., J. Biol. Chem., 272:19236-41 (1997). It was observed that the human p110δ isoform is expressed in a tissue-restricted fashion. It is expressed at high levels in lymphocytes and lymphoid tissues, suggesting that the protein might play a role in PI 3-kinase-mediated signaling in the immune system. Details concerning the p110δ isoform also can be found in U.S. Pat. Nos. 5,858,753; 5,822,910; and 5,985,589, each incorporated herein by reference. See also, Vanhaesebroeck et al., Proc. Natl. Acad. Sci. USA, 94:4330-5 (1997), and International Publication No WO 97/46688.
In each of the PI3Kα, β, and δ subtypes, the p85 subunit acts to localize PI 3-kinase to the plasma membrane by the interaction of its SH2 domain with phosphorylated tyrosine residues (present in an appropriate sequence context) in target proteins (Rameh et al., Cell, 83:821-30 (1995)). Two isoforms of p85 have been identified, p85α, which is ubiquitously expressed, and p85β, which is primarily found in the brain and lymphoid tissues (Volinia et al., Oncogene, 7:789-93 (1992)). Association of the p85 subunit to the PI 3-kinase p110α, β, or δ catalytic subunits appears to be required for the catalytic activity and stability of these enzymes. In addition, the binding of Ras proteins also upregulates PI 3-kinase activity.
The cloning of p110γ revealed still further complexity within the PI3K family of enzymes (Stoyanov et al., Science, 269:690-93 (1995)). The p110γ isoform is closely related to p110α and p110β (45-48% identity in the catalytic domain), but as noted does not make use of p85 as a targeting subunit. Instead, p110γ contains an additional domain termed a “pleckstrin homology domain” near its amino terminus. This domain allows interaction of p110γ with the βγ subunits of heterotrimeric G proteins and this interaction appears to regulate its activity.
The p101 regulatory subunit for PI3 Kgamma was originally cloned in swine, and the human ortholog identified subsequently (Krugmann et al., J. Biol. Chem., 274:17152-8 (1999)). Interaction between the N-terminal region of p101 with the N-terminal region of p110γ appears to be critical for the PI3Kγ activation through Gβγ mentioned above.
A constitutively active PI3K polypeptide is described in International Publication No. WO 96/25488. This publication discloses preparation of a chimeric fusion protein in which a 102-residue fragment of p85 known as the inter-SH2 (iSH2) region is fused through a linker region to the N-terminus of murine p110. The p85 iSH2 domain apparently is able to activate PI3K activity in a manner comparable to intact p85 (Klippel et al., Mol. Cell. Biol., 14:2675-85 (1994)).
Thus, PI 3-kinases can be defined by their amino acid identity or by their activity. Additional members of this growing gene family include more distantly related lipid and protein kinases including Vps34 TOR1, TOR2 of Saccharomyces cerevisiae (and their mammalian homologs such as FRAP and mTOR), the ataxia telangiectasia gene product (ATR), and the catalytic subunit of DNA-dependent protein kinase (DNA-PK). See generally, Hunter, Cell, 83:1-4 (1995).
PI 3-kinase also appears to be involved in a number of aspects of leukocyte activation. A p85-associated PI 3-kinase activity has been shown to physically associate with the cytoplasmic domain of CD28, which is an important costimulatory molecule for the activation of T-cells in response to antigen (Pages et al., Nature, 369:327-29 (1994); Rudd, Immunity, 4:527-34 (1996)). Activation of T cells through CD28 lowers the threshold for activation by antigen and increases the magnitude and duration of the proliferative response. These effects are linked to increases in the transcription of a number of genes including interleukin-2 (IL2), an important T cell growth factor (Fraser et al., Science, 251:313-16 (1991)). Mutation of CD28 such that it can no longer interact with PI 3-kinase leads to a failure to initiate IL2 production, suggesting a critical role for PI 3-kinase in T cell activation.
Specific inhibitors against individual members of a family of enzymes provide invaluable tools for deciphering functions of each enzyme. Two compounds, LY294002 and wortmannin, have been widely used as PI 3-kinase inhibitors. These compounds, however, are nonspecific PI3K inhibitors, as they do not distinguish among the four members of Class I PI 3-kinases. For example, the IC50 values of wortmannin against each of the various Class I PI 3-kinases are in the range of 1-10 nM. Similarly, the IC50 values for LY294002 against each of these PI 3-kinases is about 1 μM (Fruman et al., Ann. Rev. Biochem., 67:481-507 (1998)). Hence, the utility of these compounds in studying the roles of individual Class I PI 3-kinases is limited.
Based on studies using wortmannin, evidence exists that PI 3-kinase function also is required for some aspects of leukocyte signaling through G-protein coupled receptors (Thelen et al., Proc. Natl. Acad. Sci. USA, 91:4960-64 (1994)). Moreover, it has been shown that wortmannin and LY294002 block neutrophil migration and superoxide release. However, because these compounds do not distinguish among the various isoforms of PI3K, it remains unclear which particular PI3K isoform or isoforms are involved in these phenomena.
In view of the above considerations, it is clear that existing knowledge is lacking with respect to structural and functional features of the PI 3-kinase enzymes, including subcellular localization, activation states, substrate affinities, and the like. Moreover, the functions that these enzymes perform in both normal and diseased tissues remains to be elucidated. In particular, the function of PI3Kδ in leukocytes has not been characterized previously, and knowledge concerning its function in human physiology remains limited. The coexpression in these tissues of other PI3K isoforms has heretofore confounded efforts to segregate the activities of each enzyme. Furthermore, separation of the activities of the various PI3K isozymes may not be possible without identification of inhibitors that demonstrate selective inhibition characteristics. Indeed, applicants presently are not aware that such selective, or better, specific, inhibitors of PI3K isozymes have been demonstrated.
Thus, a need exists in the art for further structural characterization of the PI3Kδ polypeptide. A need also exists for functional characterization of PI3Kδ. Furthermore, understanding of PI3Kδ requires further elaboration of the structural interactions of p110δ, both with its regulatory subunit and with other proteins in the cell. A need also remains for selective or specific inhibitors of PI3K isozymes, such that the functions of each isozyme can be better characterized. In particular, selective or specific inhibitors of PI3Kδ are desirable for exploring the role of this isozyme and for development of pharmaceuticals to modulate activity of the isozyme. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to an apparatus for positioning a cutting guide in order to cut or re-cut a bone, notably a tibia and/or a femur to which a knee prosthetic shall be applied.
An apparatus for positioning a cutting guide of the above type is known from the prior art, notably from French patent application No. 98 03421 (FR 2776 176 AFSA29) dated Mar. 20, 1998 by the present applicant. The prior art positioning apparatus disclosed therein features numerous disadvantages.
Firstly, the apparatus is particularly cumbersome when cutting a tibia, as it includes a main stem and fixating means located at the bottom of a tibia.
Secondly, this positioning apparatus is not universal, e.g. an identical apparatus for positioning a cutting guide is not suitable for both a tibia cutting guide and a femur cutting guide. As can be ascertained in the prior art cited above, the apparatus for positioning the tibia cutting guide is very different from the equivalent apparatus for a femur. Consequently, manufacturers of apparatuses of this type require two distinct manufacturing lines for said two positioning apparatuses surgeons also require both positioning apparatuses at hand, which is a disadvantage.
An apparatus is described in document FR-2.776.176 which includes first adjusting means for adjusting the orientation of the cutting angle relative to a second axis perpendicular to the first anchoring axis, but which does not includes second adjusting means to adjust the height of the cutting guide relative to the positioning system along the third perpindicular axis, wherein said height is constant because brackets 83 do not slide. Moreover, this system may only be used on a femur and cannot be adapted to a tibia.
According to the present invention, an apparatus for positioning a cutting guide is provided which overcomes the prior art disadvantages detailed above and which is universal, i.e. which may be used to position a tibia cutting guide as well as a femur cutting guide, and which is much less cumbersome than the known prior art apparatuses. Moreover, the apparatus according to the invention is particulary well suited ti CAMSP (computer-assisted medical-surgical procedure) techniques.
According to the present invention, the apparatus for positioning the cutting angle of a bone cutting guide, notably a tibia and/or femur cutting guide, includes
first fastening means to fasten the positioning apparatus to the bone such that both the apparatus and the cutting guide may rotate relative to the fastening axis;
second fastening means to fasten the positioning apparatus to said bone at a second location different from the first fastening location, to fasten said apparatus at a desired location within said rotation relative to said first fastening axis;
first adjusting means for adjusting the orientation of the cutting angle rotating relative to a second axis perpendicular to first fastening axes, notably the orientation known as the antero-posterior slope; and
second adjusting means to adjust the height of the cutting guide relative to the positioning apparatus along a third axis perpendicular to said fastening axis and second axis.
According to a particularly simple embodiment of reduced proportions, said first fastening means comprises a bore implemented in the body of said positioning apparatus and a screw or broach or similar to be screwed or inserted within said bore so as to fasten to the bone. Said second fastening means comprise a second bore parallel to said first bore and a second screw or broach or similar to be screwed or inserted within said second bore to fasten to the bone.
According to a preferred embodiment of the present invention, said first adjusting means includes two brackets mounted perpendicularly to the fastening axis, wherein said two brackets are linked to the fastening means of the cutting guide and are linked to one another by a transversal bracket perpendicular to said brackets and also perpendicular to said fastening axes. Said first adjusting means also includes a screw actionable by means of a knob, which acts upon the transversal bracket so as to displace it relative to the body of the positioning apparatus following the direction of said fastening axes.
This adjusting system is relatively simple because the adjustment is performed by means of simply translating said transversal bracket. However, said translation is performed relative to the fixed body which includes a plurality of contact points located onto the bone, namely a contact point fixed relative to the bone, e.g. said fastening locations, and another contact point, e.g. a portion of the area of contact of said cutting guide with said bone. Said translation is therefore transformed into a rotation of said cutting angle within a reduced rotation angle such that the antero-posterior cutting angle is best adjusted, i.e. the cutting angle along the sagittal plane for instance. A simple apparatus is therefore obtained to adjust the knee""s antero-posterior slope contrary to particularly complicated apparatuses of the prior art.
According to another preferred embodiment of the present invention, said two vertical brackets slide relative to the main body within said third direction as a knob is acted upon, such that the height of the cutting guide to which they are attached by means of said fixating means can be adjusted relative to the body of said cutting guide and thus relative to the bone to which said cutting guide is fastened to.
According to yet another preferred embodiment of the present invention, further precision adjusting means are implemented in order to precisely adjust said rotation angle relative to said first fastening axis. Said precision adjusting means result from mounting said second bore onto a knob-operable stem, rendering said bore slideably mobile relative to the main body of the apparatus.
As first and second fixating screws are fastened into the bone to define an angle known as the varus/valgus angle with a certain amount of precision, said positioning can thus be refined by acting upon said knob, whereby said second fastening axis translates slightly relative to the body of the positioning apparatus. The varus/valgus angle can thus be slightly modified by acting upon the fastening configurations of the positioning apparatus by an angle comprised within plus or minus 3xc2x0, without however gravely deteriorating the bone. It is therefore a particularly simple structure of the apparatus.
According to still another preferred embodiment of the present invention, the cutting guide or the positioning apparatus thereof include a sensor to position the cutting angle within a space, notably within a system known as CAMSP, for instance as described in German utility patent No 297 04 393.5 dated Mar. 11, 1997 in the name of Aesculap AG.
According to another preferred embodiment of the present invention, the apparatus includes fastening means which may be removed from said cutting guide, wherein said fastening means comprises clasping pegs that may be clasped within respective appropriate lodgings implemented within the cutting guides.
The present invention also relates to the use of a positioning apparatus according to the invention, whether for a tibia or a femur.
The present invention also relates to the method of using a cutting guide including a positioning apparatus for positioning the cutting angle of a cutting guide for a bone, notably a tibia and/or a femur, including
first fastening means to fasten said positioning apparatus to the bone such that the whole of the apparatus and the fastening means of the cutting guide may rotate relative to the fastening axis; and
second fastening means to fasten said positioning apparatus at a second fastening location onto the bone, different from said first fastening location, such that said apparatus can be fastened in a required position within said rotation relative to said first fastening axis, comprising the steps of
first fastening the cutting guide positioning apparatus at a location following a first fastening axis,
when so fastened, pivoting said apparatus relative to said fastening axis into a required position, and then only
fastening said positioning apparatus at a second location following a second fastening axis. | {
"pile_set_name": "USPTO Backgrounds"
} |
Optical systems used in conventional telecommunication systems typically include a light source which supplies light that must be properly directed to a remote destination. Typically, the light source is a laser diode or an optical fiber, and the destination is a light detector or an optical fiber. Proper routing of the light requires that the light source and the remote destination be properly aligned with one another.
Proper alignment of such systems has been conventionally accomplished by repositioning the light source and/or the remote destination. Such repositioning may require re-melting the solder used for bonding the light source and/or the remote destination to an associated supporting structure. Typical lateral positioning tolerances for optical elements such as a laser diode are on the order of approximately 1 .mu.m or less. Due to such small tolerances, the laser diode and an accompanying collimating lens must be carefully bonded to a support structure to ensure that they are properly aligned. If the laser diode is positioned with a lateral control of 2 .mu.m and used with a 1 .mu.m focal length collimating lens, the pointing error can typically be 2 milliradians (vertically and horizontally).
However, even when the pointing error of the light source is controlled, the pointing error of the destination may also need to be controlled. For instance, if the destination is a collimating lens and a single-mode fiber, light from a second light source may be directed backward through the fiber and the collimating lens towards the first light source to ensure proper alignment of this first light source and the destination. If the pointing error of the collimating lens and single-mode fiber is not controlled, the light from this second light source will not reach the first light source. Accordingly, there is a need for an apparatus which adjusts for pointing errors both near a light source and a destination so that the light is properly routed from the source to the destination without having to reposition the source and/or the destination. | {
"pile_set_name": "USPTO Backgrounds"
} |
In the past decade, high-security verification based on face analysis has been an important research topic in computer vision and human-machine interaction. There are two types of verification protocols: specific person verification protocols and unspecific person verification protocols. Specific person verification involves verification of specific person, where a population of clients is fixed. Both the adopted representation (features) and the verification algorithms applied in the feature space are based on some training data collected for the client set. Thus, the system design is tuned to the specific client set. In contrast to specific person verification, unspecific person verification is verification of an unspecific person, where the client set is unknown and no samples of the client can be used during the designing stage. In such scenarios, the feature space and the system parameters are trained by subjects that are completely independent from that used for specifying client models.
Past research efforts have mainly focused on the verification of specific clients, not unspecific persons. However in recent years, there is a growing interest in finding a robust and portable (e.g., use the same feature space and the same design parameters (e.g. thresholds)) solution for unspecific person verification. Such a system would be useful in many scenarios. For example, a system for unspecific person verification would be useful in an airport where passengers show their ID cards and the photos on the cards are compared with the on-site video to verify their identities. Another example scenario that would benefit from unspecific person verification is when an existing verification system used on a first group of clients is to be used for a different group of clients. | {
"pile_set_name": "USPTO Backgrounds"
} |
In optical communication systems, large-capacity transmission based on high-speed transmission and wavelength multiplexing has been promoted. Particularly, in optical communication systems for trunk line, wavelength multiplexing communication has been widely used. In the wavelength multiplexing communication, a wavelength channel interval is prescribed and when the wavelength channel interval within a band of an optical fiber amplifier is 50 GHz, it is possible to use approximately one hundred channels.
Here, when representing a channel interval by Δf [Hz] and representing a transmission rate by B [bit/s], B/Δf [bit/s/Hz] is called a frequency efficiency. For example, when Δf=50 GHz and a transmission rate per channel is 100 Gbit/s, the frequency efficiency results in 2 bit/s/Hz.
Because the amplification band of the optical fiber amplifier is limited, in order to transmit a larger amount of information within a fixed band, it is necessary to enhance the frequency efficiency. Meanwhile, merely increasing the bit rate of a signal in order to enhance the frequency efficiency leads to a problem of cross talk between the channels. Thus, as next generation optical communication formats, an optical multiple-value modulation format and an optical orthogonal frequency-division multiplexing (OFDM) method have been considered.
The optical multiple-value modulation format increases information amount without expanding a frequency band by associating each of the amplitude and the phase of light with, not two values, that is, “0” and “1”, but multiple values. Further, in the optical OFDM, an OFDM signal, which is generated on an electric signal basis, is optical-modulated, and the optical-modulated OFDM signal is multiplexed under the state where optical subcarriers are each caused to be in a mutually orthogonal state. Thus, the optical OFDM enables reduction of the occurrence of problems due to the cross talk, and enhancement of the frequency efficiency.
Through such processing based on electric signals, digital data to be modulated is subjected to a multiple-value conversion process and a multiplexing process, and is transmitted. The transmitted light signal is demodulated into an electric signal at a receiving end.
In an optical modulation circuit of an optical transmitter, a digital/analog (D/A) converter and an optical modulator are needed in order to convert the digital data which is an electric signal into an optical analog signal waveform.
As an optical modulator used when performing such a complicated optical modulation as described above, there is a Mach-Zehnder interferometer. The Mach-Zehnder interferometer is realized as an optical waveguide using, for example, lithium niobate (LiNbO3) as the material. Hereinafter, a modulator configured by the Mach-Zehnder interferometer using the lithium niobate as the material will be referred to as an “LN modulator”.
FIG. 12 illustrates a block diagram of the LN modulator in relation to the present invention. Light is inputted from an optical input port 2 of an LN modulator 300 to an optical divider 3, and lights divided by the optical divider 3 is outputted to a first optical waveguide 4 and a second optical waveguide 5. An electrode is formed on part of each of the first optical waveguide 4 and the second optical waveguide 5. Further, it is possible to, with respect to each of the optical waveguides, vary the phase of light transmitting through the optical waveguide by applying a voltage to the electrode. Hereinafter, the first optical waveguide 4 provided with the electrode and the second optical waveguide 5 provided with the electrode will be referred to as a first phase modulator 17 and a second phase modulator 27, respectively.
Lights outputted from the first optical waveguide 4 and the second optical waveguide 5 are inputted to the optical coupler 8, and from the optical coupler 8, lights are each outputted to a corresponding one of the first optical output port 30 and the second optical output port 31.
The LN modulator 300 applies voltages to the first phase modulator 17 and the second phase modulator 27, and thereby varies the phases of lights transmitting through the waveguides. Further, it is possible to vary the intensities of lights outputted from the first light output port 30 and the second light output port 31 by utilizing a light interference effect in the optical coupler 8.
Meanwhile, an optical modulation function similar to that of the LN modulator 300 shown in FIG. 12 can be also realized by using optical waveguides composed of a semiconductor material. Currently, for realizing such an optical modulator, an indium phosphide (InP) and arsenic indium phosphide gallium (InGaAsP)-origin material and an gallium arsenide (GaAs) and aluminum gallium arsenide (AlGaAs)-origin material are proposed. Then, there has been proposed an optical modulator including a Mach-Zehnder interferometer composed of one of these semiconductor materials. With respect to such an optical modulator using the semiconductor material, generally, it is possible to lower an operation voltage for the optical modulator to a fraction of the operation voltage of the LN modulator, and further reduce the size of the optical modulator to less than or equal to one tenth as compared with that of the LN modulator. This is because a variation coefficient of a refractive index relative to the voltage with respect to a semiconductor material is larger than or equal to several ten times that of lithium niobate.
Some of optical modulators constituted by optical waveguides have a function of, for the purpose of setting an optimum operational condition, monitoring lights transmitting through the optical waveguides and feeding back the monitoring result to driving conditions for the optical modulator. In patent literature (PTL) 1 to 3, there is disclosed a configuration in which part of a light signal is monitored by using a photodiode (PD) provided at outside. Through such a configuration, characteristic deterioration during operation of the optical modulator is suppressed.
Further, in PTL4, there is disclosed a configuration of an optical FSK/SSB modulator which is capable of adjusting the intensity of a light signal outputted from a sub-Mach-Zehnder waveguide. Further, in PTL5, there is disclosed a configuration of an optical modulator provided with a Mach-Zehnder waveguide for an intensity adjustment.
Generally, the PD for monitoring light transmitting through an optical waveguide is provided at outside of the optical modulator, or, as described in PTL3, the PD is monolithic-integrated at inside of the optical modulator. Even when the PD is integrated, a signal outputted as the result of operation of a Mach-Zehnder interferometer (the signal being a signal at a portion outer than the optical coupler of the optical modulator) needs to be monitored.
Further, in the LN modulator 300 shown in FIG. 12, the configuration that lights radiated from the edges of the waveguides are monitored in order to detect the intensities of lights having transmitted through the first optical waveguide 4 and the second optical waveguide 5, it is impossible to directly grasp the light intensities inside of the optical waveguides. For this reason, with respect to the LN modulator 300 shown in FIG. 12, there has been also a problem that it is difficult to grasp the situation of light transmitting inside thereof with accuracy.
For example, in an optical modulator disclosed in PTL3, a PD for detecting the light intensity is monolithically-integrated inside the optical modulator. Nevertheless, even in the configuration disclosed in PTL3, the light intensity is monitored at a portion outer than the optical coupler. For this reason, in the configuration disclosed in PTL3, there is a problem that it is difficult to grasp the intensity of light inputted to the optical coupler with accuracy. | {
"pile_set_name": "USPTO Backgrounds"
} |
Various classes of block diagrams describe computations that can be performed on application specific computational hardware, such as a computer, microcontroller, FPGA, and custom hardware. Classes of such block diagrams include time-based block diagrams such as those found within Simulink® from the MathWorks, Inc. Natick Ma, state-based and flow diagrams such as those found within Stateflow® from the MathWorks, Inc. Natick Ma., and data-flow diagrams. A common characteristic among these various forms of block diagrams is that they define semantics on how to execute the diagram.
Historically, engineers and scientists have utilized time-based block diagram models in numerous scientific areas such as Feedback Control Theory and Signal Processing to study, design, debug, and refine dynamic systems. Dynamic systems, which are characterized by the fact that their behaviors change over time, are representative of many real-world systems. Time-based block diagram modeling has become particularly attractive over the last few years with the advent of software packages such as Simulink® from The MathWorks, Inc. of Natick, Mass. Such packages provide sophisticated software platforms with a rich suite of support tools that makes the analysis and design of dynamic systems efficient, methodical, and cost-effective.
A dynamic system (either natural or man-made) is a system whose response at any given time is a function of its input stimuli, its current state, and the current time. Such systems range from simple to highly complex systems. Physical dynamic systems include a falling body, the rotation of the earth, bio-mechanical systems (muscles, joints, etc.), bio-chemical systems (gene expression, protein pathways), weather and climate pattern systems, etc. Examples of man-made or engineered dynamic systems include: a bouncing ball, a spring with a mass tied on an end, automobiles, airplanes, control systems in major appliances, communication networks, audio signal processing, nuclear reactors, a stock market, etc. Professionals from diverse areas such as engineering, science, education, and economics build mathematical models of dynamic systems in order to better understand system behavior as it changes with the progression of time. The mathematical models aid in building “better” systems, where “better” may be defined in terms of a variety of performance measures such as quality, time-to-market, cost, speed, size, power consumption, robustness, etc. The mathematical models also aid in analyzing, debugging and repairing existing systems (be it the human body or the anti-lock braking system in a car). The models may also serve an educational purpose of educating others on the basic principles governing physical systems. The models and results are often used as a scientific communication medium between humans. The term “model-based design” is used to refer to the use of block diagram models in the development, analysis, and validation of dynamic systems.
Often, the complexity of block diagram models results in a need for substantial memory and/or processing capabilities. A need exists to seek to reduce the memory and/or processing requirements, to enable faster response of a simulation of a block diagram model. Faster responses, particularly in the case of a real-time model used in a control system, can enable the use of lower cost processing hardware and/or memory. Also, a need exists to aid a user in the management of a block diagram model. | {
"pile_set_name": "USPTO Backgrounds"
} |
Heart disease is the leading cause of death in the United States. A common and life-threatening complication of heart disease is myocardial infarction resulting from a thrombus that obstructs blood flow in one or more coronary arteries. The sooner thrombolytic medication such as tissue plasminogen activator (tPA) or urokinase is placed into the patient's bloodstream after the occurrence of an acute myocardial infarction, the sooner an obstructive thrombus will be dissolved and perfusion of the myocardium will be restored. The extent of damage to the myocardium is strongly dependent on the length of time that occurs prior to restoration of some blood flow to the heart muscle. At this time, no system exists that provides for early and automatic detection of an acute myocardial infarction and for rapidly providing the patient with a prescribed dose of a thrombolytic medication.
There are many patients who have implanted heart pacemakers or implanted cardiac defibrillators (ICDs). The purpose of the pacemaker is to provide a low energy electrical stimulation pulse that causes the heart to beat at a prescribed rate. The purpose of the defibrillator is to shock the heart back into sinus rhythm after ventricular fibrillation has been detected. However, no existing implantable pacemaker or defibrillator is also able to detect a partial or complete blockage of a coronary artery and warn the patient that this potentially fatal event is occurring. Furthermore, no pacemaker or ICD is presently used with an external communication and action system that rapidly responds to acute myocardial infarction or reversible myocardial ischemia that is detected by specially designed circuitry in that implanted pacemaker or ICD.
Although anti-tachycardia pacemakers and ICDs can detect heart arrhythmias and respond with electrical stimulation, none are currently designed to be part of a rapid response system designed to inform the patient as to his condition and to facilitate the injection of an anti-arrhythmic drug with a minimum time delay.
It is well known that an acute myocardial infarction can be detected from a patient's ECG by noting an ST segment deviation (i.e., voltage change) as compared to the voltage of the patient's TP or PQ segments. Such an ST segment deviation can be even more clearly discerned with electrodes implanted within the body (especially within or in close proximity to the heart) as compared with detecting the elevated ST segment from chest and/or limb mounted electrodes.
In U.S. Pat. Nos. 6,112,116 and 6,272,379 issued to R. E. Fischell, et al, an implanted cardiosaver system is described that includes an automatic delivery of medication when a heart attack is detected. These patents also teach the combination of internal and external alarm systems for informing the patient that a heart attack has been detected. However, the long term storage of any thrombolytic or anti-thrombogenic medication within a human patient can cause a deterioration of such drugs. Except for the treatment of an acute myocardial infarction, neither of these patents teaches how an external system could be used to treat any potentially fatal or at least worrisome cardiac event such as an arrhythmia and/or myocardial ischemia that is caused by an elevated heart rate resulting from physical effort including exercise.
In U.S. Pat. No. 5,479,780 by M. Zehender, a device is described that has a “goal of eliminating . . . cardiac rhythm abnormality.” In order to accomplish this goal, Zehender requires exactly two electrodes placed within the heart and exactly one electrode placed outside the heart. Although multiple electrodes could be used, an ideal sensor for providing an electrogram to detect a heart attack would use a single electrode placed within the heart. The Zehender patent teaches the detection of an ST segment deviation to indicate coronary ischemia and to use an implanted drug pump to release medication to treat such an ischemia. However, Zehender never discusses the treatment of acute myocardial infarction. Rather, the purpose of Zehender's invention is only to warn of an arrhythmia caused by myocardial ischemia Zehender does not indicate that his invention could be used for the treatment of a heart attack. Furthermore, Zehender does not consider the problem of drug deterioration when such a drug is stored within an implanted device for later release when ischemia is detected. Still further, ischemia can result from exercise when there is progression of a stenosis in a coronary artery. Under such circumstances it would be highly undesirable to release a medication designed to treat the ischemia caused by a heart attack. Furthermore, Zehender does not describe an external system to be used in conjunction with an implanted cardiosaver device. Thus Zehender does not teach the use of an external alarm means or means to have a diagnostic center always on call for immediate diagnosis of a potentially fatal heart attack or arrhythmia. Furthermore, Zehender does not teach an implanted drug port that can be used for rapidly providing a bolus of medication from an external source to be delivered into a patient having a heart attack by either the patient himself, a caretaker of the patient or by a paramedic from an ambulance. Although Zehender does describe the use of a pacemaker or defibrillator in conjunction with an implanted device for detecting ischemia, he does not describe either an external alarm system to be used with the implant, nor does he describe the use of an implanted drug port to be used with the pacemaker or defibrillator.
The electrical signal from the heart as measured from electrodes within the body is called an “electrogram”. The early detection of an acute myocardial infarction or myocardial ischemia caused by an increased heart rate or exertion is clearly feasible by using an implantable system that notes a change in a patient's electrogram. The implanted device portion of such a system is defined herein as a “cardiosaver” and the entire system including the implanted cardiosaver and the external portions of the system is defined herein as the “cardiosaver system.” Furthermore, although the masculine pronouns “he” and “his” are used herein, it should be understood that the patient or the medical practitioner who treats the patient could be a man or a woman. Still further the term; “medical practitioner” shall be used herein to mean any person who might be involved in the medical treatment of a patient. Such a medical practitioner would include, but is not limited to, a medical doctor (e.g., a general practice physician, an internist or a cardiologist), a medical technician, a paramedic, a nurse or an electrogram analyst. A “caretaker” is defined herein as a person that can come to the aid of the patient if the cardiosaver system indicates the occurrence of some cardiac related event such as a heart attack or ventricular fibrillation. A caretaker would include, but is not limited to, the patient's spouse, an attendant in a nursing home, a nurse or any person assigned to help take care of the patient. A “cardiac event” includes an acute myocardial infarction, ischemia caused by effort (such as exercise) and/or an elevated heart rate, bradycardia, tachycardia or an arrhythmia such as atrial fibrillation, atrial flutter, ventricular fibrillation, and premature ventricular or atrial contractions (PVCs or PACs). The use of this invention to treat stroke, will for the purposes of this specification, also be considered to be a “cardiac event”. For the purpose of this invention, the term “electrogram” is defined to be the signal from an implanted electrode that is placed in a position to indicate the heart's electrical activity. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a semiconductor integrated device, and more particularly, to semiconductor integrated device including a Fin Field effect transistor (hereinafter abbreviated as FinFET) device and protecting structures.
2. Description of the Prior Art
Conventional planar metal-oxide-semiconductor (MOS) transistor has difficulty when scaling down to 65 nm and below. Therefore the non-planar transistor technology such as Fin Field effect transistor (FinFET) technology that allows smaller size and higher performance is developed to replace the planar MOS transistor.
The FinFET device is conventionally formed by: First a silicon layer of a substrate is patterned to form fin structures (not shown) by a proper etching process. Then, an insulating layer surrounding lower portions of the fin structures is formed and followed by forming a gate covering a portion of the insulating layer and top portions of the fin structures. Next, dopants are introduced and annealing treatments are performed to form source/drain in the fin structures not covered by the gate. Since the manufacturing processes of the FinFET device are similar to the traditional logic device processes, it provides superior process compatibility. Furthermore, when the FinFET device is formed on the SOI substrate, traditional shallow trench isolation (STI) is no longer in need. More important, since the FinFET device increases the overlapping area between the gate and the fin structures, the channel region is more effectively controlled. This therefore reduces drain-induced barrier lowering (DIBL) effect and short channel effect, and the current between the source and the drain is increased.
However, the FinFET device still faces many problems. For example, because the fin structures are long and slim plate-like structures, they are susceptible to physical or electrical impacts. The long and slim fin structures are even damaged upon those impacts. Therefore, a strong and sufficient protecting structure is always in need for the FinFET device. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a coating method and a resist coater for coating a resist film on a wafer. More particularly, the invention relates to a coating method and a resist coater for coating a resist film having a thickness of 5500 .ANG. or less on a wafer having a large diameter of 8 inches or more by a spin coating process, wherein the resist film is free from unevenness in the coating of the resist film and favorable in an in-plane evenness in film thickness and film quality. Incidentally, the resist film in this specification refers to a wide concept including a photoresist film.
2. Description of the Related Art
In a manufacturing process of a semiconductor device, when patterning is performed by etching, a resist film mask having a desired pattern Is formed on a layer to be etched, and the layer is etched by the use of the mask.
A resist film for forming a mask is normally formed on a layer to be etched by coating a resist on a wafer using a resist coater and baking the resist.
By the way, according to a higher integration of a semiconductor device, each elements in the semiconductor device including wirings is made more and more fine. In the generation of the fine pattern rule of 0.35 .mu.m or less, the thickness of a resist film which is coated on a wafer is made thinner and thinner for reasons in the etching processing. In particular, in an resist coating process which requires a coating of a reflection preventing film, in order to secure evenness in film thickness and prevent generation of unevenness in reflection as can be seen in pin holes, it is required to set the thickness of the reflection preventing film to 2000 .ANG. or more.
On the other hand, in order to improve precision in dry etching for a resist resolution pattern, and in order to prevent the neighboring resist patterns from being connected, it is required to set the total thickness of the reflection preventing film and the resist film to 7000 .ANG. or less. Consequently, it is inevitably required to set the thickness of the resist film to 5500 .ANG. or less.
Before explaining a conventional coating method, a resist coater for coating a resist on a wafer will first be explained with reference to FIG. 1. FIG. 1 is a sectional view showing a structure of a conventional resist coater of a spin coat type.
As shown in FIG. 1, a resist coater 10 has a wafer holding table 12 for rotating a wafer W around an axis which is perpendicular to the wafer W while holding the wafer W with a wafer surface thereof directed upwardly. A resist supply nozzle 14 supplies resist to the wafer W which is held on the wafer holding table 12. A coater cup 16 surrounds the wafer holding table 12 and the resist supplying nozzle 14.
The wafer holding table 12 is attached on an upper end of a rotation shaft 18 which penetrates a bottom portion of the coater cup 16 and which is rotated with a rotation device (not shown). The wafer holding table 12 is provided on its wafer holding surface with a chuck mechanism for vacuum-sucking the wafer W, and it is rotated together with the rotation shaft 18 around an axis which is perpendicular to the wafer holding surface.
The coater cup 16 is provided for trapping resist particle which are scattered from the wafer W by a centrifugal force due to rotation of the wafer W, and the coater cup 16 has an outer cup 20 for trapping resist particles which are scattered in a sidewise and an upward directions, and an inner cup 22 for guiding resist particles which are scattered in a downward direction from the wafer W to a bottom portion of the outer cup 20.
The outer cup 20 has at an upper portion thereof an opening 24 for introducing the resist supply nozzle 14 or the like, and for taking in and taking out the wafer W. Furthermore, the inner cup 22 is provided on a lower portion of the outer cup 20, and the inner cup 22 has a cylindrical portion 22a, and an umbrella portion 22b which spreads toward the inside of the coater cup 16 from an upper opening thereof.
The resist supply nozzle 14 is lowered from the above via the opening 24 of the coater cup 16, and is arranged at a position facing a resist coating surface of the wafer W. Also, in order to clean an edge to the back surface of the wafer W, a first cleaning nozzle 26 for spraying rinse agent is provided to be directed toward the edge of the back surface of the wafer W through the bottom portion of the coater cup 16. Furthermore, in order to clean an edge of the surface of the wafer W, a second cleaning nozzle 28 for spraying rinse agent is provided to be directed toward the edge of the wafer W via the upper opening 24 of the coater cup 16.
Exhaust pipes 30 connected to an exhaust device (not shown) for exhausting the inside of the coater cup 16, and a drain pipe 32 for exhausting the resist trapped in the coater cup 16 are connected to the bottom portion of the coater cup 16.
Following, a conventional method for coating a resist film by the use of the above-mentioned resist coater 10 will be explained by giving an example of forming a resist film having a thickness of 5500 .ANG. on an 8 inch wafer. FIG. 2 is a graph showing a rotating speed of a wafer of each step in the conventional method.
When a resist film having a thickness of 5500 .ANG. or less, for example, 5000 .ANG., is coated on an 8 inch wafer, the coating process is conventionally performed in the following procedure.
Resist having, for example, a relatively low viscosity on the order of 7 cp is used for a resist film. The wafer is held on the wafer holding table 12 and the resist is first dripped on a wafer from the resist supply nozzle 14 while rotating the wafer at a low rotation speed of 1000 rpm, and the resist is spread on the whole surface of the resist coating surface of the wafer for 4 seconds.
Next, the dripping of resist is suspended, and the wafer is rotated for 19 seconds at a rotation speed of 5000 rpm, so that a resist film having a desired thickness, i.e., of 5000 .ANG. is formed.
Subsequently, rinse agent is sprayed from the first cleaning nozzle 26 for 20 seconds, and the back surface edge of the wafer is cleaned. Also, rinse agent is sprayed from the second rise nozzle 28, and the surface edge of the wafer is cleaned. Thus, the coating step is terminated.
Subsequently, the process proceeds to the following baking step, where the residual solution in the resist is completely removed.
However, in the case where a resist film having a thickness of 5500 .ANG. or less on a 8 inch or more wafer in accordance with the conventional coating method, an in-plane unevenness regarding film thickness and film quality are not favorable, so that variations occur in film thickness and film quality. For example, when a high speed rotational coating is performed on an 8 inch or more wafer, variations in the resist film thickness occur in the in-plane of the wafer in a range of 90 .ANG. or more.
As a consequence, problems are caused in a photolithography stop and an etching step which follow the coating step. For example, there arise a problem that unevenness occurs in wiring width which is obtained in the etching, which results in difficulty in improvement in product yield.
Specifically, on a wafer having a large diameter of 8 inches or more, when the wafer is rotated for 20 seconds or more at a rotation speed of 5000 rpm after dripping the resist agent, a coating unevenness occurs and generated at a constant cycle on a peripheral portion of the wafer having a width of 20 mm from an outer periphery thereof inwardly. For example, in an example according to the method described above, the coating unevenness occurs on the peripheral portion of the wafer, and a variation in the resist film thickness is caused between a central portion of the wafer and the peripheral portion thereof due to the coating unevenness. Thus, as shown in FIG. 3, variations in the fill thickness exceeding 100 .ANG. are generated within the in-plane of the wafer.
With respect to a 6 inch wafer, for reference, even when the wafer is rotated for 20 seconds or more at a rotation speed of 6000 rmp after dripping the resist agent on the wafer, it never happens that the coating unevenness occurs in the peripheral portion of the wafer. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to communication systems. In particular, the present invention relates to estimation of frequency and phase of analog signals.
2. Description of Related Art
Many modern day communications systems modulate phase and/or frequency of a carrier signal in order to convey information. In a communication receiver or a signal measurement instrument, a typical objective is to reverse the modulation operation on the received signal and determine the phase and/or frequency of the carrier signal.
Processing techniques used in a communications receiver may be analog or digital. In many modern day communication systems, signal processing is conducted digitally. In traditional receivers for reception of phase/angle modulated signals, analog-to-digital (A/D) conversion, down conversion to baseband, and, phase/frequency extraction are conducted separately. Typically the task of phase/frequency extraction is conducted after A/D conversion and the down conversion may be performed before or after A/D conversion depending on the system design preferences.
In such designs, the A/D conversion sub-system is optimized to get a high quality digital representation of the analog input signal. The design criterion for such systems has been based on minimizing the analog-to-digital converter (ADC) output signal amplitude quantization error. However, this is not necessarily optimal if the parameter of interest is actually the frequency and/or phase of the input signal. A system based on reducing the distortion in the frequency/phase of the input signal due to A/D conversion is likely to yield higher performance.
Accordingly, it is desirable to have a method and apparatus to efficiently and accurately estimate and/or digitize the instantaneous frequency and/or phase of an analog signal.
The present invention provides a method and apparatus to detect the instantaneous frequency of a signal. A sampler is used to sample the input signal. A metric generator uses the samples of the input signal to generate a metric signal whose magnitude is related to the instantaneous frequency of the input signal. With a minor modification to the frequency detector architecture, a power detector is obtained.
System, method and apparatus that are used for detecting and digitizing the instantaneous frequency of a signal are described. These utilize the frequency and power detectors. However, their use is not limited to frequency and power detectors presented with this patent application. These can be implemented with other types of frequency and power detectors. In one embodiment of the invention, the apparatus that is used to digitize the instantaneous frequency of a signal comprises a feedback circuit and a decimator. The feedback circuit generates a sequence signal from the input signal. The sequence signal contains the necessary information to detect and digitize the instantaneous frequency of the input signal. The decimator is coupled to the feedback circuit to decimate the frequency signal to generate a frequency signal. The frequency signal providing the instantaneous frequency of the input signal. Various embodiments of the feedback circuit are disclosed including an interpolative circuit and a predictive circuit. | {
"pile_set_name": "USPTO Backgrounds"
} |
Computer systems are designed in such a way that software application programs share common resources. It is traditionally the task of an operating system to provide mechanisms to safely and effectively control access to shared resources. In some instances the centralized control of elements, critical to software applications, hereafter called critical system elements (CSEs) creates a limitation caused by conflicts for shared resources.
For example, two software applications that require the same file, yet each requires a different version of the file will conflict. In the same manner two applications that require independent access to specific network services will conflict. A common solution to these situations is to place software applications that may potentially conflict on separate compute platforms. The current state of the art, defines two architectural approaches to the migration of critical system elements from an operating system into an application context.
In one architectural approach, a single server operating system places critical system elements in the same process. Despite the flexibility offered, the system elements continue to represent a centralized control point.
In the other architectural approach, a multiple server operating system places critical system elements in separate processes. While offering even greater options this architecture has suffered performance and operational differences.
An important distinction between this invention and prior art systems and architectures is the ability to allow a CSE to execute in the same context as an application. This then allows, among other things, an ability to deploy multiple instances of a CSE. In contrast, existing systems and architectures, regardless of where a service is defined to exist, that is, in kernel mode, in user mode as a single process or in user mode as multiple processes, all support the concept of a single shared service. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to an electrical outlet box, more specifically to an electrical outlet box for housing wiring connections and/or electrical devices with embossed side walls which provide additional space within the box.
Electrical outlet boxes are commonly used as junction boxes for connecting wires or for housing and connecting a switch, an electrical receptacle or other type of electrical device. Outlet boxes are typically attached to a wood or metal wall stud. Most outlet boxes of the prior art have a rectangular shape and have an opening next to the stud. An aperture is cut in the outer wall covering in order to access the inside of the outlet box. The outlet box must be properly positioned in relation to the stud and the outer covering, such as wall board or sheetrock, which is later placed over the stud. The outer wall covering placed on the stud is a gypsum board material or wood panel with a thickness of from ¼ to 1 inch. Therefore, the outlet box must be positioned so that it extends through the outer covering to allow the outlet box to be accessed.
Electrical outlet boxes can be made in one of two different ways. The first design is a modular design, wherein the four side walls and back wall of the open-front box are fastened together using bolts or screws. These types of boxes are called “gangable electrical outlet boxes.” The sides are fastened together, either by the consumer or by the manufacturer, before the box is installed.
One problem with gangable boxes is that, since they are constructed using various bolts/screws, the bolts/screws holding the box together can loosen and compromise the integrity of the electrical outlet box. Another problem with gangable boxes is the considerable time and effort required for the user to properly assemble the outlet boxes.
A second type of electrical outlet box design is called a “non-gangable outlet box.” This type of box is welded together using a bead weld or a tackweld at various points where the walls adjoin. Although non-gangable boxes solve some problems associated with gangable boxes, there are additional problems encountered when using non-gangable boxes.
One problem with non-gangable boxes is that the interior space of typical non-gangable electrical outlet boxes is limited. Non-gangable outlet boxes typically have a rear wall and four flat side walls extending therefrom to create a rectangular box. The interior space of these non-gangable boxes is limited and it can be difficult for the user to connect wires or an electrical device in the outlet box. Another problem with non-gangable boxes is that, typically, there are no features on the box which assist the user in positioning the box on the structural support before it is permanently mounted.
Accordingly, it is desirable to provide an outlet box which facilitates the attachment of the box to a support. There is also a need for an outlet box which has sufficient interior space to allow a user to easily connect wires to electrical devices housed in the box. There is a further need for an electrical outlet box which is rigidly constructed and eliminates unnecessary assembly time prior to installation. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a document processing technique, and more particularly, relates to a method and system for expanding a document set as a search data source in the enterprise search field.
2. Description of the Related Art
Today's enterprises have increasing types of electronic documents and data information. How to utilize such information to help an enterprise's business development and strategy decisions has attracted great attention. Enterprise search technology provides an effective way to help enterprises process such ever increasing data information. However, not all data are suitable as a search data source in an enterprise search.
The traditional information source upon which the search of a general search engine is based is a mass information source. The search result is also mass data information. A great number of search results may not be desired by a user, and the enterprise search user can seldom obtain the desired information by eliminating noise from such mass data information. Thus, in the enterprise search field, for a particular business demand such as performing market analysis on an industry or determining an enterprise for investment, it is impossible to collect all the Web data for performing a search due to limitation of resources. However, as much relevant information as possible must be acquired.
With the expeditious increase of Internet based documents, the data source for an enterprise search must be constantly updated and extended. Thus, a significant challenge in the field of enterprise search technology is to effectively and automatically extend the search data source for enterprise search services to help an enterprise collect information useful to businesses from a mass of web data. This will help eliminate unnecessary “noisy” information to promote data source utility and save storage resources for the search data source.
In the related art, a user of an enterprise search service recommends relatively valuable documents which he or she obtained from an enterprise search service system. The documents were stored in an information memory device of the enterprise search service system and then became a public enterprise search data source. Further, a system administrator for the enterprise search service keeps a close eye on the change of web information at any moment and adds useful information to the enterprise search data source. However, the above manners of expanding search data source cannot automatically implement expansion based on the existing documents in the data source for enterprise search, which is totally dependent on actions of users of the enterprise search service and the system administrator. This not only consumes time and energy but also has low efficiency in expanding the data source. | {
"pile_set_name": "USPTO Backgrounds"
} |
A known form of picture rail apparatus comprises a rail member which is mounted horizontally on the wall, the rail member being formed with a longitudinally-extending slot. The slot is elongated in transverse section, and has a narrow opening at the front of the rail member. The apparatus includes a support member on which the picture or other article can be supported. The support member is formed with a thin tongue, and in use is detachably mounted on the rail member with the tongue slidingly engaged in the slot.
An advantage of this apparatus is that the rail member can be made quite thin and can be inset in the wall, with its slotted face flush with the wall surface. This gives a neat and attractive appearance to the wall, and facilitates decoration of the wall surface, since the apparatus avoids the obtrusive projection from the wall which is encountered with the more conventional projecting picture rails.
In the known form of the apparatus, the slot has been inclined downwardly transversely rearwardly from the opening. This is intended to make the engagement more secure, since it is to be expected that the downward pull of the article being supported would cause the tongue to seat more firmly in the slot. However, the present applicant has found that the support which is obtained is not sufficiently secure in all cases, and, particularly when used with relatively heavy articles, the support members tend to fall out of the slot. Further, the support members can be accidentally disengaged by an inadvertent lateral pull, for example when re-arranging the supported articles.
Applicant is aware of U.S. Pat. No. 46,296, Colburn, which describes a coat and hat hook which has a T-shaped projection lodging in a U-shaped groove in a rail. The Colburn arrangement is, however, designed to be affixed to the exterior of the wall and is not adapted to be inset in a wall surface.
U.S. Pat. Nos. 1,800,386 to Hoffman and 1,800,387 to Greist show channel-section rails which receive sliding support devices, but these are of considerable vertical thickness and are received in a wide channel which is not easily concealed in a wall surface.
U.S. Pat. Nos. 3,684,229 to Peter et al and 3,892,739 to Hoes disclose a mountings for specialised metal fittings but the mountings are not directly adaptable for receiving and retaining a thin tongue of a picture hook or like member. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The field of invention relates to storage rack apparatus, and more particularly pertains to a new and improved newspaper storage rack wherein the same secures a rectangular stack of newspapers and provides binding means for subsequent binding and securement of a newspaper stack.
2. Description of the Prior Art
In contemporary society, storage for subsequent disposal or recycling of newspapers is desirable to prevent undesirable strewing of such newspapers when not properly secured and positioned. Prior art storage rack apparatus includes U.S. Pat. No. 3,952,876 to Price providing a storage rack formed of wire or rod utilizing a base and upwardly extending legs to surroundingly secure a newspaper stack therewithin.
U.S. Pat. No. 4,193,340 to Finn sets forth a receptacle for securement of newspaper therewithin, wherein vertically arranged posts mounted on a support stand utilize string members secured to boss members of each post for subsequent tying of the newspaper bundles together.
U.S. Pat. No. 4,298,126 to Filipowicz sets forth a holder wherein a central support base includes a plurality of "U" shaped legs extending upwardly therefrom to secure a stack of papers therewithin.
U.S. Pat. No. 4,395,941 to Metzger sets forth a paper file and stack arrangement wherein a plurality of spools of string arranged rotatably within the base, wherein the base includes a series of upwardly extending legs for surrounding engagement of a bundle of stacked newspapers therewithin.
As such, it may be appreciated that there continues to be a need for a new and improved newspaper storage rack as set forth by the instant invention which addresses both the problems of ease of use as well as effectiveness in construction and in this respect, the present invention substantially fulfills this need. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention comprises an improved reflecting mirror for spotlights. Conventional reflecting mirrors for spotlights are well known in the art. As shown in FIG. 1, these mirrors generally comprise a parabolic shaped dish with a reflective inner surface (1) and an aperture in the axial center through which a light source protrudes. The light source can be an incandescent lamp (3) which emits light when a filament (2) is energized with current. The reflective inner surface of the parabolic shaped dish reflects light from the light source forward, thereby efficiently illuminating the light source.
In this general configuration of a floodlight reflecting mirror, the reflected illuminated light can have uneven brightness. This results from an unevenness in the light emission from the filament source. In extreme cases, a magnified image of the filament may be projected.
To address this problem, reflective mirrors have been developed with a plurality of small, approximately round reflective spots on the inner periphery of the mirror, each individual spot with either a concave or convex surface. This configuration is designed to diffuse the reflected light so that more evenly diffused lighting is achieved. Although this configuration may improve the evenness of illuminated light, the process of creating and manufacturing such a reflective parabolic mirror is very difficult.
Another reflective mirror configuration designed to solve the problem of uneven reflected light is shown in FIG. 2. In this configuration, the reflective mirror inner periphery (4) is subdivided into a plurality of expanding annular rings (5) with their center at the reflective mirror axial center with a protruding incandescent lamp (6). Each of these annular rings has a convex surface, so that the reflected light will diffuse and be distributed more evenly. With this configuration uneven shading of the filament in the direction of the optic axis of the incandescent lamp (6) is diffused and brightness is made uniform by the reflection on the surface of the annular rings, the unevenness of the filament in the direction of the whole circumference that exists in the orthogonal plane to the optical axis cannot be diffused.
Therefore an unresolved need exists in industry for an effective and economically feasible floodlight reflective mirror. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a railcar for renovating railways and more precisely to a railcar comprising an operating unit equipped for the execution, in sequence, of the following operative steps: removal of the old tracks, removal of the old track supporting sleepers, remaking of the laying plane of the new sleepers, laying of new sleepers; and wherein said operating unit is provided with supporting means to allow its advancement on the old sleepers already stripped of their tracks.
Railcars of the specified type have been hitherto produced, intended to operate continuously for the total renovation of the railway, i.e. for the total replacement of the old track supporting sleepers, the total remaking of their laying plane, the laying on said plane of new sleepers and the successive remaking of the ballast by means of the deposition of new rubble and/or of regenerated rubble in the spaces comprised between the new sleepers.
For this purpose, currently known renovation railcars are mostly equipped with means for removing the old sleepers capable of systematically removing them from the ballast and of depositing them on conveyors which transfer them to an accumulation area on board the railcar, with one or more plowshares for removing the displaced rubble and for levelling the laying plane and with elements, generally acting by gravity, for laying, regularly spaced, the new sleepers on the previously levelled laying plane.
With known railcars of the specified type it is therefore not possible to execute interventions for maintenance or revision entailing the partial and occasional replacement of the sleepers in the section involved, and on the other hand such partial interventions are often sufficient to restore the original efficiency and safety of the track with markedly lower costs.
The inadequacy of known railcars for partially renovating tracks essentially derives from the fact that the current systems for stripping the old sleepers are incapable of extracting them from their related original seats without damaging the laying plane of said seats, so that the laying of the new sleepers entails the complete remaking of said plane. | {
"pile_set_name": "USPTO Backgrounds"
} |
For inks, paints, sealants, PVC sols, acrylic sols and the like, they are first prepared in the form of a paste sol and the paste sol is then used to implement coating, painting, application, mixing or other operations. If properties, quality or other conditions of a cured product do not allow the incorporation of so much filler into the paste sol, there is used a filler capable of imparting, even in a small amount, a high viscosity to the sol, such as fumed silica.
Fumed silica allows the sol to exhibit high thixotropy, however, simultaneously providing high viscosity. Furthermore, fumed silica also presents a problem in that it extremely changes the sol viscosity with a very small variation in additive amount.
Meanwhile, calcium carbonate is used as a filler for various polymeric materials, such as plastics, rubbers, inks, paints, sealants, PVC sols, and acrylic sols. Therefore, if the addition of calcium carbonate can impart high thixotropy to these materials, calcium carbonate can be used as a relatively inexpensive thixotropy imparting agent.
Patent Literature 1 discloses a surface-treated calcium carbonate that is a calcium carbonate surface-treated with an unsaturated fatty acid and a saturated fatty acid in a predetermined mixture ratio. When this surface-treated calcium carbonate is used and added to inks, paints, sealants, PVC sols, acrylic sols and the like, high thixotropy can be imparted to these materials.
However, from viewpoints of environmental health and other factors, consideration has recently been given to saving the usage of diluent, plasticizer and the like. With the use of the surface-treated calcium carbonate in the above known technique, the materials can achieve high thixotropy but increases the viscosity, which makes it difficult to save the usage of diluent and plasticizer. Therefore, there is demand for a surface-treated calcium carbonate capable of imparting high thixotropy together with low viscosity.
Patent Literature 2 also proposes a surface-treated calcium carbonate for imparting high thixotropy. However, also with the use of the surface-treated calcium carbonate disclosed in this known technique, it is difficult to impart both of low viscosity and high thixotropy.
Patent Literature 3 proposes a calcium carbonate surface-treated with a surface treatment agent containing lauric acid and myristic acid in a total content of 85% or more. However, also with the use of this surface-treated calcium carbonate, it is difficult to impart both of low viscosity and high thixotropy. | {
"pile_set_name": "USPTO Backgrounds"
} |
In recent years, screening for weapons at entrances of public places, such as airports, government buildings, public schools, and amusement parks, has increased to ensure safety for the public at those places. Screening for weapons can include requiring people entering such public places to pass through a magnetic screening system such as a portal metal detector. Although people have become accustomed to passing through portal metal detectors, the process remains relatively slow for a number of reasons.
One reason for the slow process is that people must empty their pockets of all metallic objects, remove their coats, and sometimes remove their shoes. The objects and clothing are either physically inspected by hand or passed through an x-ray machine for visual screening. Another reason for the slow process is due to false detection or detection of non-weapon metals, such as wrist watches, belt buckles, metallic wires found in ordinary garments, personal adornments such as broaches or hair clips, and loose coins in pockets.
Yet another reason for the slow processing is due to machine settling times, which refers to the amount of time that must be allowed for the sensors in metal detectors to resettle after a person passes through it. Allowing a portal metal detector sufficient time to settle ensures accurate readings of the next person. A person who passes through the portal metal detector then stops on the other side very close to the portal metal detector (i.e., within an ‘influence’ zone) can also influence the metal detector to such an extent that the metal detector makes a false detection or misses detecting an object as the next person passes through it. Therefore, portal metal detector operators must stop the next person from entering the portal metal detector until the previous person has passed beyond the influence zone.
Typically, all of the delays result in a passthrough rate of between one and two hundred persons per hour. To accommodate large crowds, many portal metal detectors are operated in parallel, which leads to staffing, training, and machine calibration issues. If the passthrough rate were higher, many venues that are currently equipped with large numbers of portal metal detectors could reduce the number in use, and venues such as sports stadiums not currently equipped with portal metal detectors would be so equipped.
Moreover, today's portal metal detectors are sensitive to large ferromagnetic objects, such as wheelchairs. When a person in a wheelchair passes through the portal metal detector, the portal metal detector is overwhelmed by the metal content of the wheelchair and unable to detect relatively small metal objects on the person. In addition, even if the wheelchair is not passing through the portal metal detector, it can influence the detector to such an extent that the detector makes erroneous readings.
In addition to the slow process associated with today's portal metal detectors and their sensitivity to large ferromagnetic objects, many portal metal detectors are ‘active,’ meaning they emit an electro-magnetic field in a volume of interest (i.e., the area in the portal metal detector). Active detectors can be dangerous for people using medical devices, such as pacemakers, that are sensitive to electro-magnetic fields. Passive metal detectors, which sense a local disturbance in the earth's magnetic field, do not affect medical devices, but they are sensitive to local magnetic fields, large ferromagnetic devices, calibration errors, background offsets, and other measurement disturbances known in the art. | {
"pile_set_name": "USPTO Backgrounds"
} |
Windows used in motor vehicles often have a latch assembly securing a windowpane to the motor vehicle. Flip windows are used, for example, as side windows on minivans. Known latch assemblies, particularly those used for flip windows in motor vehicles, allow the windowpane to pivot out or up to a fixed distance. This allows a given amount of air into the motor vehicle without having the windowpane extend too far from the exterior sheet metal of the motor vehicle. The latch assembly for the flip window often has a latch base attached near one edge of the windowpane, connected to a latch anchor which is in turn attached to the motor vehicle. Operation of the latch assembly allows the windowpane to pivot away from the motor vehicle on a hinge attached near a second edge of the windowpane opposite the latch base. Such latch assemblies typically have pivotable links connecting the latch anchor to the latch base. The links pivot to a fully extended position as the windowpane pivots from a closed position to a full open position.
In recent years it has become desirable to use increasingly large windowpanes on motor vehicles to enhance aesthetics and visibility. It has also become desirable to mount the windowpane essentially flush with an exterior surface of the motor vehicle. However, errors in the sheet metal of the motor vehicle surrounding the opening receiving the windowpane and tolerance variations in the windowpane itself may position the windowpane is an aesthetically unappealing non-flush or otherwise somewhat misaligned position. That is, the windowpane, while functional, may be aesthetically unattractive as the windowpane can be slightly misaligned with respect to the rest of the motor vehicle. It would be desirable for the assembler of the window assembly to the motor vehicle to be able to adjust the latch assembly to compensate for any such slight misalignment.
In view of the foregoing, it is an object of the present invention to provide a latch assembly for a window assembly which is adjustable to accommodate manufacturing tolerance problems and is of low cost. It is another object of the present invention to provide a latch assembly for an articulating window assembly of a motor vehicle positioned free of an outer surface of the windowpane. It is another object of the present invention to provide a latch assembly for a window assembly which closes an opening in a motor vehicle and is positioned flush with an exterior surface of the motor vehicle. It is yet another related object of the present invention to provide such a latch assembly that is highly reliable in operation. | {
"pile_set_name": "USPTO Backgrounds"
} |
In the Patent Specification Serial No. 482,881 of the June 25, 1974, there was described a device for correcting the air-fuel dose of internal combustion engines comprising at least one auxiliary air inlet connected to the induction manifold of the engine downstream of the member determining the dosing of the air-fuel-mixture, at least one control valve controlling the said auxiliary air inlet or inlets, the said control valve being controlled by the negative pressure prevailing in the throat of the venturi of the dosing device by means of a capsule whose diaphragm, elastically preloaded, is subjected to the said negative pressure by way of a conduit opening into the said body, the said negative pressure being itself modified by an electromagnetic valve, the opening of which is controlled by a probe arranged in the exhaust manifold and adapted to deliver an electrical current adapted to be varied in accordance with the composition of the burned gases.
The applicants have found that the device thus described is directly applicable to internal combustion engines using a gas fuel, or internal combustion engines combining the use of two fuels by using the auxiliary air inlet as a fuel gas inlet.
When the fuel is only gas, the carburettor can be dispensed with, and in that case there only remains in the induction pipe the venturi making it possible to take the dynamic negative pressure prevailing in the induction pipe, followed by the butterfly valve for regulating the air intake, the gas inlet conduit opening downstream of the said butterfly valve.
When the carburettor is retained, it is regulated so as to provide a lean mixture and the probe ensures the automatic regulation of the additional fuel gas. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to an apparatus and process for heating and/or cooling of the intake air to a combustion gas turbine. More particularly the invention relates to a skid mounted modular unit that is manufactured off site and transported to the turbine location and connected with a minimum of on site construction. Most particularly the invention relates to a process and apparatus that utilize the exhaust heat from the turbine to indirectly heat the intake air to the turbine.
2. Related Information
In industry combustion gas turbines [C.G.T.""s)] (C.G.T.""s) drive a variety of devices (i.e., generators, gas compressors, pumps, etc.) and are subject to continually changing ambient conditions, which can adversely affect their power output. The combustion gas turbine industry has always struggled with controlling the power of the turbine at varying intake ambient air temperatures. Some problems listed below (not all inclusive) are typical of users of combustion gas turbines have struggled with since the development of the combustion gas turbine:
1. Varying inlet temperatures resulting in varying combustion gas turbine power outputs and thus unpredictable work produced.
2. Varying temperatures related to increased maintenance and operating costs.
3. Conventional inlet chilling (using basic liquid chillers) and heating costs were high.
4. Conventional inlet chilling using basic liquid chillers of the reciprocating, screw or centrifugal type refrigeration compressors were not large enough regarding capacity to cool the combustion gas turbine large mass flow rates with redundant systems.
5. Basic liquid chillers with their ancillary components (pumps, cooling tower, electrical switchgear, piping, control systems, sound components, weatherproofing costs, buildings, civil work, and field assemble labor) required large physical areas to field assemble.
6. Field erected systems have been undependable with regard to guaranteed performance and parasitic electrical loads of the systems have been too high to justify installation.
7. Alternate methods of inlet cooling, such as evaporative cooling or water atomization into the combustion gas turbine inlet, while low in initial cost, do not maintain steady inlet temperatures with varying ambient conditions. Since these methods are completely dependent on evaporation of water, the higher the wet bulb temperature, the less effectively they cool. It is typically at high wet bulb temperature conditions that maximum combustion gas turbine output is needed.
The present invention comprises a modular unit in which all of the components necessary for conditioning the intake air for a combustion gas turbine are contained. The compressors, evaporators condensers and related pumps and control equipment are contained within a weather proof enclosure having sound insulation installed in the walls.
There are many aspects of the present invention that are unique and that have not been known in the prior art. These novel features include but are not limited to:
1. A single lift packaged modular combustion gas turbine chilling, control and monitoring system that can be installed without the use of (a) multiple disciplines, (b) engineering and construction site contractors, (c) untested products, (d) multi component vendors (i.e., chillers, pumps, controls, electrical components, etc.), (d) guesswork, (f) field welding, (g) insulation, (h) piping, (i) instrumentation, (j)structural systems, (k) weatherproofing and (l) provisions for extreme systems.
2. The present modular system is different from field erected systems in that it:
(a) can be operated in hazardous environments without costly xe2x80x9cexplosion proofingxe2x80x9d electrical modifications.
(b) responds directly to C.G.T. operator""s inlet air temperature sensing which is part of the operator""s digital control system (D.C.S.). Field erect systems typically respond to chilling fluid temperatures.
(c) provides electrical parasitic load (KW) data directly to operator""s D.C.S. console.
(d) provides auto-switchover of 100% stand-by pump on condender water or chilling liquid. Field erect systems require operator manual changeover with valves.
(e) provides the entire process in fully weatherproof, thermally insulated, and sound attenuated enclosures. Field erected systems offer none of these items and require a building to provide any protection. Field erect systems offer no integrated modular designs on cooling and no optional integrated C.G.T. inlet heating modules for direct integration into the chilling process by way of:
1. control system
2. piping and valves
3. heat exchanger
4. electrical system
5. commonality of components
(f) provides compact, single lift modules, factory assembled, tested, and transportable on major highways to any site.
(g) provides portable modules, easily moved to other sites and quickly connected for operation.
(h) provides large capacity (cooling tons) modules which use simple 2-flow pass heat exchangers on liquid chilling [(evaporator-drawing 01)] and condensers [(drawing 01)], eliminating extensive and complicated series and parallel flow arrangements common to some field erected systems.
(i) provides available multiple centrifugal compressors on single heat exchanger vessels for stand-by capability (50%/50%) and very efficient operation at partial loads. No other system offers this.
(j) provides fully independent microprocessor control and safety logic for each centrifugal compressor.
(k) uses R-134a xe2x80x9cchlorine freexe2x80x9d refrigerant in capacities over 1,500 tons, an exclusive.
(l) has the ability to control module temperature (ventilation, cooling, heating, and/or humidity control) surrounding all process system components so they are not affected by changing outdoor weather, and exclusive.
(m) is fully assembled, pre-piped, pre-wired, insulated, and tested prior to shipment, and exclusive.
(n) has the ability to reclaim C.G.T. exhaust heat through thermal oil/E.G. liquids and provide heating at C.G.T. inlet with the common components of the chilling system is unique to this process.
(o) provides centrifugal compressors on liquid chilling systems are aircraft derivative design for fast start and fast stop of compressors, saving energy and eliminating costly xe2x80x9ccoast downxe2x80x9d lubrication systems.
(p) provides single point power connections for entire system electrical distribution, safety, back up, and operation, a unique feature.
(q) provides reclaiming inlet chilling coil condensate to cooling tower make-up water stream for less make-up water usage and to improve tower efficiency. | {
"pile_set_name": "USPTO Backgrounds"
} |
Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a rotor assembly for producing power. The rotor assembly is formed from a plurality of turbine blades extending radially outward from a rotor. Each turbine blade is formed from a root portion having a platform at one end and an elongated portion forming a blade that extends outwardly from the platform. The blade is ordinarily composed of a tip opposite the root section, a leading edge, and a trailing edge. The root typically is attached to a disk of the rotor assembly with a plurality of serrations extending from the disk that mesh with a plurality of serrations extending from the disk to fixedly attach the blade to the rotor. While the turbine blade is fixedly attached to the rotor, there typically exists sufficient play in the attachment mechanism that the turbine blade may move.
During use, the rotor, in one particular turbine engine, rotates at about 3600 revolutions per minute (RPM). In this operating mode, the centrifugal forces created cause the turbine blades to extend radially outward without any movement relative to the rotor assembly to which the turbine blades are attached. However, in another mode in which the rotor is rotated very slowly by a turning gear, such as about 2 RPM, the turbine blades rock back and forth causing wear as the rotor is turned slowly. In particular, many turbine engines are kept in a ready state through use of turning gears that enable a turbine engine to be quickly brought to steady state operating conditions. In some situations, turbine engines are run with a turning gear for long periods, such as for several continuous months. At such a slow RPM, gravitational forces are stronger than centrifugal forces, thereby causing the turbine blades to rock back and forth, causing turbine blade root serration wear on both the rotor serrations and the blade root serrations as well. The rocking motion also causes hard face coating damage on shrouded turbine blades and, in some instances, has caused rotor cracking.
The wear caused by the rocking action of the turbine blades also frustrates efforts to take blade tip readings as well. In particular, when blade tip readings are performed in the field, the operator must physically lift or wedge each blade into the running position while taking the blade tip reading. Lifting each turbine blade by hand takes time and often results in inaccurate blade tip readings.
Previous attempts to curb root serration wear have been attempted but have not been successful. For instance, seal pin slots on the turbine blades have been enlarged and larger pins have been used. However, the turbine blade serrations have continued to wear resulting in rotor repair and scrapping of the turbine blades. Thus, a need exists for reducing wear on turbine blade root serrations. | {
"pile_set_name": "USPTO Backgrounds"
} |
Wireless network adjustment is a routine operation performed daily by wireless network operators to design a new wireless network or to optimize an existing network. Changes in a network may be made for many reasons including the need to improve coverage, quality of service, and capacity. Such changes are generally necessitated by many factors, including performance issues from customer complaints, field test data, switch or other network operational measurement, changing antenna setting requirements or constraints, including zoning, leasing or structural changes, increasing or shifting usage including movement of high usage areas. Depending upon the values of any of these factors, network engineers may be required to change antenna parameters to increase the capacity, coverage, and quality of service offered to users of the network. Network engineers may also be required to change antenna parameters to compensate for changes in environmental parameters determined by attributes of a received signal.
Antenna parameters may include any one or combination of antenna discrimination pattern, either by changing the antenna model or adjusting the discrimination parameters of an adjustable antenna, azimuth, mechanical down-tilt, electrical down-tilt, and twist, power, and changes in antenna height.
Presently, network engineers utilize a radio-frequency (RF) planning tool for determining required changes to a network. For each network change, the network engineer may be required to perform multiple steps of manually recording alternations in various configuration dialogs/tables, performing several network analysis steps, and generating and examining the results that indicate if the alteration(s) compensated for the changes in environmental parameters and/or increased the capacity, coverage, and quality of service. Network engineers may also employ a polling system to compensate for changes in environmental parameters. Typical prior art polling systems introduce lag because the systems request data every N seconds. Due to the delay between requests, a spike in received signal level (RSL) values or other signal attribute values may occur between polls, and there may not be an indication of this event. Thus, appropriate updates to the system may be lost and a full record of values cannot be captured and/or maintained.
It is apparent that the aforementioned processes are inefficient, inaccurate and time-consuming. Further, the processes may result in less than optimal network changes and a reluctance to utilize the full potential of available predictive tools. Therefore, a need exists for real-time monitoring of environmental parameters.
Accordingly, there is a need for a method and apparatus for a novel method and system that would overcome the deficiencies of the prior art. There is also a need for real-time RSL monitoring control. Therefore, an embodiment of the present subject matter provides a method for monitoring an attribute of a received signal in a wireless network having plural radios wherein one of the radios includes a monitoring module operatively connected to a second network. The method comprises the steps of monitoring substantially continuously an attribute of a radio at the monitoring module and providing a display device operatively connected to the second network. The method further comprises the steps of transmitting via the second network to the display device a value representative of the current state of the attribute wherein the transmitting occurs upon a change in the state of the attribute from a previous state of the attribute, and displaying the value on the display device.
Another embodiment of the present subject matter provides a system for monitoring an attribute of a received signal in a wireless network having plural radios. The system comprises a monitoring module operatively connected to a radio in the wireless network and operatively connected to a second network wherein the monitoring module substantially continuously monitors an attribute of the radio. A display device may be operatively connected to the second network. The monitoring module may transmit, via the second network to the display device, a value representative of the current state of the attribute wherein the monitoring module transmitter transmits upon a change in the state of the attribute from a previous state of the attribute.
These embodiments and many other objects and advantages thereof will be readily apparent to one skilled in the art to which the invention pertains from a perusal of the claims, the appended drawings, and the following detailed description of the embodiments. | {
"pile_set_name": "USPTO Backgrounds"
} |
Availability of up-to-date information is more important today than ever before and this will continue to be true for the foreseeable future. People want to be well informed, so much so that they travel with cellular phones, beepers, and even portable hand-held Global Positioning System (GPS) satellite receivers.
GPS capable devices generally have a GPS receiver for receiving satellite signals from the GPS satellite network that allow for determination of the device's position. Such devices allow for precisely locating the device in terms of latitude and longitude using the GPS receiver. Some devices have map data stored in memory and a display for showing the device position with reference to the map data. Other devices have no underlying map data base for reference. Rather, they show only the geographic coordinates of the device's location. These coordinates may be referred to as waypoints. Most GPS receiver devices can store many waypoints. Some GPS receiver devices can plot and display a trail of waypoints and store this trail for future retrieval. Sophisticated devices may compute the device's heading, speed, and other information based on comparisons with previous GPS determined positions.
GPS receiver devices with map display capability may store the map information on computer diskettes, CD-ROM's, or other computer memory storage devices. The device location may then be displayed on a display terminal with reference to a map stored in the computer memory storage device. The available quantity of map data, however, can overwhelm the memory capability of easily portable computer devices. This problem is exacerbated when additional information is included and linked with the map data. In addition, information is more valuable when it is up to date and available at the time of consumption, and such devices do not incorporate a means for updating the stored information. By way of example, a CD ROM could never maintain an up-to-date list of every 5-star restaurant.
Some GPS receiver devices have the ability to communicate over a telecommunications network. These devices do not provide for automatic or semi-automatic dynamic exchange of on-line position dependent or related information. In addition, these devices cannot communicate with third parties in the absence of a uniform data format standard. For example, a cellular-phone-based system comprising GPS location information working in conjunction with proprietary Public Safety Answering Point (PSAP) telephone equipment is known. The device provides personal and medical information on an emergency basis to the proper authorities. Such a device does not allow third parties to communicate, tag, interrogate, limit, designate, modify or share this information amongst themselves for any other use.
To that end, the ability to receive digital data structures with GPS encoding, and storing this information for eventual use or broadcast to third parties, would be valuable. Today, the U.S. and several other countries have independent publishers busily GPS mapping everything down to the most minute detail. Most of these data bases are available on CD ROM storage. The problem is that no one data base can contain enough information to fulfill the unique requests of every particular and picky consumer. The costs associated with providing and maintaining such a large data base would be overwhelming and over-burdening. Additionally, most consumers do not like reading or compiling vast data bases. | {
"pile_set_name": "USPTO Backgrounds"
} |
A metal oxide semiconductor field effect transistor (MOSFET) is essentially a four terminal device: gate, drain, source and body. In almost all conventional MOSFETs the body is permanently internally attached to the source, and only three terminals are brought out for connection to other circuit elements. An N-Channel MOSFET, often written NMOSFET, will not block positive current flow from the source to the drain, irrespective of the gate voltage, if the drain to source voltage, denoted VDS, is <−0.7V due to the body diode inherent in the NMOSFET. Similarly, a P-Channel MOSFET, often written PMOSFET, will not block positive current flow from the drain to the source, irrespective of gate voltage, if VDS is >+0.7V due to the body diode inherent in the PMOSFET. It is possible to implement back-to-back MOSFETs, in which the drain of a first MOSFET is connected to the source of a second MOSFET of a similar channel so as to block this body diode sourced current flow, but the penalty is that the back-to-back MOSFETs have twice the channel resistance of a single MOSFET.
As described above, for an NMOSFET, if the drain is at a lower potential than the body by a diode drop, current will flow through the body to the drain, which from the outside world appears as current flow from source-to-drain. Similarly, for a PMOSFET, if the drain is at a higher potential than the body by a diode drop, current will flow through from the drain to the body, which from the outside world appears as current flow from drain to source. There is no inherent requirement that the body of the MOSFET be attached to the source, but to prevent body diode conduction, it is necessary that the body be held at an appropriate potential in relation to either side of the MOSFET channel.
Many circuits, particularly synchronous secondary side regulation schemes, would benefit from a MOSFET that when turned off would block current flow from both drain to source and from source to drain, over a wide range of potentials. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a coupling arrangement in general, and more particularly to an arrangement for alignedly coupling two coated light-conductive fibers.
There are already known various arrangements for coupling or alignedly interconnecting two light-conductive fibers at their end portions. The light-conductive fibers, which are usually used for transmitting signals or the like, are, more often than not, externally coated in order to minimize intensity losses of the light being transmitted through the light-conductive fibers. While the distance which is to be traversed by the light rays conducted through the light-conductive fiber may be sometimes small enough for use of only a single section of the light-conductive fiber, it is often necessary to compose a light-conductive line of a plurality of such sections, particularly when the distance to be traversed exceeds the length of a single available light-conductive fiber section. When this is the case, it is necessary to securely connect the light-conductive fiber sections with one another in such a manner that the end portions of the light-conductive fiber sections which are juxtaposed with one another at their respective end faces are in perfect axial alignment with one another in order to avoid light losses at the juncture of the sections.
To achieve this axial alignment of the light-conductive fibers of the sections, it has already been proposed to mount three clamping bars in a support sleeve in such a manner that the axes of these clamping bars are located at the vertices of an imaginary isosceles triangle so that the clamping bars define between themselves a passage in which the light-conductive fibers to be joined or coupled are received. Then, the clamping bars are pressed inwardly against the end portions of the light-conductive fibers received therebetween, thereby clampingly engaging the two end portions in a perfect axial alignment with one another. Usually, the inward pressing is performed by deflectable members which are acted upon, in the axial direction, by actuating elements which are introduced into the support sleeve through the respective end portions thereof.
The coupling arrangement of the above-mentioned type excellently solves the problem of precisely aligning the end portions of the light-conductive fibers with one another and of arresting the end portions in their aligned positions. However, experience with this conventional arrangement has shown that, particularly in view of the relatively small transverse dimensions of the light-conductive fibers, it is very difficult to introduce the end portions of the light-conductive fibers into the passage defined between the clamping rods. Another problem which has been encountered in the above-discussed conventional coupling arrangement is that, in some applications, it is necessary to disassemble the connection of the light-conductive fibers. The above-mentioned conventional arrangement is not capable of disassembly without a complete dismantling of the coupling arrangement, which is a rather serious drawback in the above-mentioned applications inasmuch as it involves a very time-consuming disassembling and assembling operation. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention is related to the field of superscalar microprocessors and, more particularly, to reorder buffers within superscalar microprocessors.
2. Description of the Relevant Art
Superscalar microprocessors achieve high performance by executing multiple instructions per clock cycle and by choosing the shortest possible clock cycle consistent with the design. As used herein, the term xe2x80x9cclock cyclexe2x80x9d refers to an interval of time accorded to various stages of an instruction processing pipeline within the microprocessor. Storage devices (e.g. registers and arrays) capture their values according to the clock cycle. For example, a storage device may capture a value according to a rising or falling edge of a clock signal defining the clock cycle. The storage device then stores the value until the subsequent rising or falling edge of the clock signal, respectively. The term xe2x80x9cinstruction processing pipelinexe2x80x9d is used herein to refer to the logic circuits employed to process instructions in a pipelined fashion. Although the pipeline may be divided into any number of stages at which portions of instruction processing are performed, instruction processing generally comprises fetching the instruction, decoding the instruction, executing the instruction, and storing the execution results in the destination identified by the instruction.
In order to increase performance, superscalar microprocessors often employ out of order execution. The instructions within a program are ordered, such that a first instruction is intended to be executed before a second instruction, etc. When the instructions are executed in the order specified, the intended functionality of the program is realized. However, instructions may be executed in any order as long as the original functionality is maintained. For example, a second instruction which does not depend upon a first instruction may be executed prior to the first instruction, even if the first instruction is prior to the second instruction in program order. A second instruction depends upon a first instruction if a result produced by the first instruction is employed as an operand of the second instruction. The second instruction is said to have a dependency upon the first instruction.
Another hazard of out of order execution occurs when two instructions update the same destination storage location. If the instruction which is second in the original program sequence executes first, then that instruction must not update the destination until the first instruction has executed. Often, superscalar microprocessors employ a reorder buffer in order to correctly handle dependency checking and multiple updates to a destination, among other things. Instructions are stored into the reorder buffer in program order, typically as the instructions are dispatched to execution units (perhaps being stored in reservation stations associated therewith) The results of the instructions are stored into the destinations from the reorder buffer in program order. However, results may be provided to the reorder buffer in any order. The reorder buffer stores each result with the instruction which generated the result until that instruction is selected for storing its result into the destination.
A reorder buffer is configured to store a finite number of instructions, defining a maximum number of instructions which may be concurrently outstanding within the superscalar microprocessor. Generally speaking, out of order execution occurs more frequently as the finite number is increased. For example, the execution of an instruction which is foremost within the reorder buffer in program order may be delayed. Instructions subsequently dispatched into the reorder buffer which are not dependent upon the delayed instruction may execute and store results in the buffer. Out of order execution may continue until the reorder buffer becomes full, at which point dispatch is suspended until instructions are deleted from the reorder buffer. Therefore, a larger number of storage locations within the reorder buffer generally leads to increased performance by allowing more instructions to be outstanding before instruction dispatch (and out of order execution) stalls.
Unfortunately, larger reorder buffers complicate dependency checking. One or more source operands of an instruction to be dispatched may be destination operands of outstanding instructions within the reorder buffer. As used herein, a source operand of an instruction is a value to be operated upon by the instruction in order to produce a result. Conversely, a destination operand is the result of the instruction. Source and destination operands of an instruction are generally referred to as operand information. An instruction specifies the location storing the source operands and the location in which to store the destination operand. An operand may be stored in a register (a xe2x80x9cregister operandxe2x80x9d) or a memory location (a xe2x80x9cmemory operandxe2x80x9d). As used herein, a register is a storage location included within the microprocessor which is used to store instruction results. Registers may be specified as source or destination storage locations for an instruction.
The locations from which to retrieve source operands for an instruction to be dispatched are compared to the locations designated for storing destination operands of instructions stored within the reorder buffer. If a dependency is detected and the corresponding instruction has executed, the result stored in the reorder buffer may be forwarded for use by the dispatching instruction. If the instruction has not yet executed, a tag identifying the instruction may be forwarded such that the result may be provided when the instruction is executed.
When the number of instructions storable in the reorder buffer is large, the number of comparisons for performing dependency checking is also large. Generally speaking, the total number of comparisons which must be provided for is the number of possible operands of an instruction multiplied by the number of instructions which may be concurrently dispatched, further multiplied by the number of instructions which may be stored in the reorder buffer. Additionally, more than one destination operand within the reorder buffer may be stored within the storage location indicated for a source operand. Circuitry is therefore employed to detect the last of the destination operands indicated by the comparisons, in order to correctly detect the dependency (i.e. the instruction which stores a result into a storage location used for a source operand and which is nearest to the dispatching instruction in program order is the instruction upon which the dispatching instruction depends) It is desirable to reduce the complexity of dependency checking for reorder buffers.
Still further, reorder buffers typically allocate a storage location for each instruction dispatched during a particular clock cycle. The number of storage locations allocated varies from clock cycle to clock cycle depending upon the number of instructions dispatched. Additionally, a variable number of instructions may be retired from the reorder buffer. Logic for allocating and deallocating storage locations is complicated by the variable nature of storage access, creating a larger and typically slower control unit used in the reorder buffer. A faster, simpler method for allocating reorder buffer storage is desired.
The problems outlined above are in large part solved by a reorder buffer in accordance with the present invention. The reorder buffer is configured into multiple lines of storage, wherein a line of storage includes sufficient storage for instruction results and information regarding a predefined maximum number of concurrently dispatchable instructions. A line of storage is allocated whenever one or more instructions are dispatched. Advantageously, the amount of storage allocated is constant. Therefore, storage allocation logic depends only upon whether or not instructions are dispatched during a clock cycle. In particular, allocation logic is independent of the number of instructions dispatched during a clock cycle. Allocation logic may thereby be simplified, allowing for higher frequency applications.
Similarly, instructions are retired from the reorder buffer after each of the instructions within a line of storage have provided results. The instructions within the line are retired simultaneously. Therefore, the amount of storage deallocated during a clock cycle is dependent only upon whether or not instructions are retired during the clock cycle, not upon the number of instructions retired. Advantageously, storage deallocation logic may be simplified as well.
In one embodiment, a microprocessor employing the reorder buffer is also configured with fixed, symmetrical issue positions. The symmetrical nature of the issue positions may increase the average number of instructions to be concurrently dispatched and executed by the microprocessor. Since the issue positions are symmetrical, any random group of instructions executable by the issue positions may be dispatched to the issue positions. In contrast, asymmetrical issue positions may impose additional restrictions upon the concurrent dispatch and execution of instructions. Increasing the average number of concurrently dispatched instructions may be particularly beneficial when employed with the line-oriented reorder buffer, since a line of storage is allocated regardless of the number of instructions dispatched. The average number of unused locations within the line decreases as the average number of concurrently dispatched instructions increases.
One particular implementation of the reorder buffer includes a future file for reducing dependency checking complexity. The future file replaces the large block of comparators and prioritization logic ordinarily employed by reorder buffers for dependency checking. The future file includes a storage location corresponding to each register within the microprocessor. The reorder buffer tag (or instruction result, if the instruction has executed) of the last instruction in program order to update the register is stored in the future file. The reorder buffer provides the value (either reorder buffer tag or instruction result) stored in the storage location corresponding to a register when the register is used as a source operand for another instruction.
Another advantage of the future file for microprocessors which allow access and update to portions of registers is that narrow-to-wide dependencies are resolved upon completion of the instruction which updates the narrower register. Previously, the instruction which updates the narrower register might typically be retired prior to resolving the narrow-to-wide dependency. Generally, instruction retirement occurs subsequent to completion of the instruction. Performance of the microprocessor may be increased due to the earlier resolution of the narrow-to-wide dependencies.
Broadly speaking, the present invention contemplates a reorder buffer comprising an instruction storage and a first control unit. The instruction storage includes multiple lines of storage, wherein each of the lines of storage is configured to store a predefined maximum number of instructions concurrently receivable by the reorder buffer. Coupled to the instruction storage, the first control unit is configured to allocate one of the lines of storage to one or more concurrently received instructions. One of the lines of storage is allocated regardless of a number of the concurrently received instructions.
The present invention further contemplates an apparatus for reordering instructions which were executed out of order, comprising a first decode unit, a second decode unit, and a reorder buffer. The first decode unit is configured to decode and dispatch a first instruction. Similarly, the second decode unit is configured to decode and dispatch a second instruction concurrent with the first instruction. Coupled to both the first decode unit and the second decode unit, the reorder buffer is configured to allocate a line of storage to store instruction results corresponding to the first instruction and the second instruction upon dispatch of the first instruction and the second instruction. The line of storage is configured to store a maximum number of concurrently dispatchable instructions and is allocated regardless of a number of concurrently dispatched instructions provided at least one instruction is dispatched.
The present invention still further contemplates a method for operating a reorder buffer. Up to a predefined maximum number of concurrently dispatched instructions are received into the reorder buffer. Upon receipt of the concurrently dispatched instructions, a fixed amount of storage is allocated for instruction results. The fixed amount of storage is sufficient to store the maximum number of concurrently dispatched instructions regardless of a number of concurrently dispatched instructions. The fixed amount of storage is subsequently deallocated upon receipt of an instruction result corresponding to each of the concurrently dispatched instructions.
The present invention additionally contemplates a method for ordering instructions in a microprocessor employing out of order execution. Up to a maximum number of instructions are concurrently dispatched. A line of storage is allocated within a reorder buffer for storing instruction results corresponding to the instructions which are concurrently dispatched. The line of storage is configured to store a number of instruction results equal to the maximum number of instructions. The instructions are executed in a plurality of functional units. Upon execution, corresponding instruction results are provided to the reorder buffer. The line of storage is deallocated when each of the corresponding instruction results within the line of storage have been provided.
The present invention also contemplates a superscalar microprocessor comprising a plurality of fixed, symmetrical issue positions and a reorder buffer. The plurality of fixed, symmetrical issue positions is coupled to receive instructions. An instruction received by one of the plurality of issue positions remains within that one of the plurality of issue positions until the instruction is executed therein. Coupled to receive operand information regarding a plurality of concurrently dispatched instructions from the plurality of fixed, symmetrical issue positions, the reorder buffer is configured to allocate storage for instruction results corresponding to the plurality of concurrently dispatched instructions.
Furthermore, the present invention contemplates a superscalar microprocessor comprising a first and second decode unit, a first and second reservation station, and a reorder buffer. The first decode unit is configured to decode a first instruction. Similarly, the second decode unit is configured to decode a second instruction concurrently with the first decode unit decoding the first instruction. Coupled to receive the first instruction from the first decode unit, the first reservation station is configured to store the first instruction until the first instruction is executed. Likewise, the second reservation station is coupled to receive the second instruction from the second decode unit and to store the second instruction until the second instruction is executed. The reorder buffer is coupled to the first decode unit and the second decode unit, and receives an indication of the first instruction and the second instruction from the first decode unit and the second decode unit, respectively. Additionally, the reorder buffer is configured to allocate a line of storage to store a first instruction result corresponding to the first instruction and a second instruction result corresponding to the second instruction. The line of storage comprises a fixed amount of storage capable of storing instruction results corresponding to a maximum number of concurrently dispatchable instructions.
Moreover, the present invention contemplates a reorder buffer comprising an instruction storage, a future file, and a control unit. The instruction storage is configured to store instruction results corresponding to instructions. The instruction results are stored in lines of storage, wherein a line of storage is configured to store instruction results corresponding to a maximum number of concurrently dispatchable instructions. A first line of storage is allocated upon dispatch of at least one instruction regardless of a number of instructions concurrently dispatched. The future file is configured to store a reorder buffer tag corresponding to a particular instruction. The particular instruction is last, in program order, of the instructions represented within the instruction storage having a particular register as a destination operand. Additionally, the future file is further configured to store a particular instruction result corresponding to the particular instruction when the particular instruction result is provided. Coupled to the instruction storage and the future file, the control unit is configured to allocate the first line of storage for at least one instruction. Still further, the control unit is configured to update the future file if the instruction has the particular register as a destination operand.
The present invention yet further contemplates a reorder buffer comprising a future file, an instruction storage, and a control unit. The future file has a storage location for each register implemented by a microprocessor employing the reorder buffer. The storage location is divided into a first portion and a second portion, corresponding to a first portion and a second portion of the register, respectively. Each of the first and second portions of the storage location is configured to store a reorder buffer tag of an instruction which updates the corresponding portion the register. Additionally, each of the first and second portions of the storage location is configured to store data corresponding to an instruction result of the instruction identified by the reorder buffer tag, wherein the data replaces the reorder buffer tag when the data is provided. The instruction storage is configured to store instruction results corresponding to multiple instructions outstanding within the microprocessor. Coupled to the future file and the instruction storage, the control unit is configured to allocate storage within the instruction storage upon dispatch of at least one instruction. Still further, the control unit is configured to store a first reorder buffer tag into the first portion of the storage location if at least one instruction updates the first portion of the register. Similarly, the control unit is further configured to store the first reorder buffer tag into the second portion of the storage location if at least one instruction updates the second portion of the register.
The present invention additionally contemplates a microprocessor comprising a reorder buffer and a register file. The reorder buffer includes a future file having a storage location for each register implemented by the microprocessor. The storage location is divided into a first portion and a second portion, wherein the first portion of the storage location corresponds to a first portion of the register and the second portion of the storage location corresponds to a second portion of the register. Each of the first portion of the storage location and the second portion of the storage location is configured to store a reorder buffer tag of an instruction which updates the first portion of the register and the second portion of the register, respectively. Still further, each of the first and second portions of the storage location is configured to store data corresponding to an instruction result of the instruction identified by the reorder buffer tag, respectively. The data replaces the reorder buffer tag when the data is provided. Coupled to the reorder buffer, the register file is configured to store a plurality of values corresponding to the registers implemented by the microprocessor. The reorder buffer updates the register file upon retirement of the instruction. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Technical Field
The present invention relates to an active matrix type TFT array substrate on which a thin film transistor (hereinafter referred to as TFT) is mounted to serve as a switching element, to a liquid crystal display using the TFT array substrate, and to a manufacturing method of them.
2. Background Art
Researches and developments of liquid crystal display to serve as a flat panel display in substitution for CRT have been popularly carried out. In particular, making use of its feature of small power consumption and small thickness, several liquid crystal displays have been heretofore put into practical use to serve as a display for ultra small size television or for notebook type personal computer driven by battery. As a drive method of the liquid crystal display, an active matrix type TFT array is principally used in which TFT is used as a switching element from the viewpoint of high display quality.
To achieve small power consumption in the liquid crystal display, it is effective to increase an effective display area of picture element section of the liquid crystal panel, i.e., to enhance aperture ratio of picture element. As a TFT array effective for achieving a liquid crystal panel of a high aperture ratio, for example, the Japanese Patent Publication (examined) Nos. 2521752 and 2598420 and the Japanese Laid-Open Patent Publication (unexamined) No. 163528/1992, etc. disclose a structure. In this structure, after forming a TFT comprising a scanning electrode, a signal electrode and a semiconductor layer, an interlayer insulating film composed of a transparent resin is formed to coat the TFT, and a picture element electrode is formed on the uppermost layer.
A high aperture ratio is achieved in the mentioned structure principally by following two reasons. In the first place, as the picture element electrode is formed on the interlayer insulating film of transparent resin of which surface is flattened, it is possible to prevent a deficient display (domain phenomenon) caused by irregular orientation of liquid crystal molecules occurring at the step portion of the picture element electrode of the conventional structure, whereby it becomes possible to increase an effective display area. In the second place, by forming the picture element electrode on the relatively thick interlayer insulating film of 0.3 xcexcm to 2 xcexcm in thickness, no electric short circuit takes place between the scanning line or signal line located at the lower layer of the interlayer insulating film and the picture element electrode located on the upper layer, and therefore it becomes possible to form the picture element electrode in wider area to overlap those lines.
A manufacturing process of the mentioned known TFT array of high aperture ratio is hereinafter described. First, a TFT comprising gate electrode, gate insulating film, semiconductor layer, source electrode, and drain electrode is formed on a transparent insulating substrate such as glass substrate. Then, an interlayer insulating film composed of a transparent resin of which surface is flattened so as not to produce any step caused by the TFT is formed, and a contact hole is formed at required portions. Finally, a picture element electrode composed of a transparent conductive film such as ITO is formed, thus a TFT array being completed. The picture element electrode is electrically connected to the drain electrode on the lower layer through the contact hole formed in the interlayer insulating film.
As described in the Japanese Laid-Open Patent Publications (unexamined) Nos. 127553/1997 and 152625/1997, methods for forming a contact hole in the interlayer insulating film are classified into one method in which a photosensitive transparent resin (having a photosensitivity) is used, and into another method in which non-photosensitive transparent resin (having no photosensitivity) is used. In the case of using a photosensitive transparent resin, a required contact hole is formed by a photomechanical process, without using any resist, in which exposure and development are performed using a mask pattern of the contact hole after application and baking of the resin. On the other hand, in the case of using a non-photosensitive transparent resin, after applying and baking the resin, a resist is applied. Then, after forming a contact pattern by photomechanical process, a dry etching is performed using a gas containing at least one of CF4, CF3 or SF6, and finally by removing the resist, a required contact hole is achieved.
On the mentioned TFT array substrate, terminals electrically connected to each of the date line, the source lines, etc. are arranged on the periphery of the image display section, whereby a terminal region for connecting each terminal to an external terminal is formed. FIG. 18 is a partially top view showing an active matrix type TFT array substrate of high aperture ratio according to the prior art. In the drawing, reference numeral 1 indicates a glass substrate being a transparent insulating film, numeral 2 indicates a gate line formed on the glass substrate 1, and numeral 3 indicates a source line crossing over the gate line 2. Numeral 4 is a gate terminal electrically connected to the gate line 2, and numeral 5 is a source terminal electrically connected to the source line 3. Numeral 6 is an interlayer insulating film composed of a photosensitive transparent resin formed to cover the entire gate line 2 and source line 3 and end portions of the image display section side of the gate terminal 4 and the source terminal 5. Numeral 7 is a guard resistance, numeral 8 is a contact hole of the terminal section, and numeral 9 is a contact hole of the guard resistance section. Numeral 14 is a short ring which is formed to prevent an electrostatic destruction of the TFT at the time of manufacturing thereof, and connects electrically respective terminals to each other through the guard resistance 7.
In the active matrix type substrate of above arrangement, at the end portions on the image display section side of the gate terminal 4 and the source terminal 5, a metallic wiring on the lower layer such as gate line 2, source line 3, etc. and a transparent conductive film on the upper layer are connected to each other through the contact hole 8 formed in the interlayer insulating film 6. On the other hand, since the interlayer insulating film 6 is not formed at the end portion on the guard resistance 7 side of each terminal and at the guard resistance section 7, a photomechanical process is separately required to form, for example, the contact hole 9 in the guard resistance section.
A transparent conductive film such as ITO is used as a picture element electrode and an upper conductive film of the gate terminal 4 and the source terminal 5, and this ITO is formed by forming a film on the entire substrate and patterning the film. However, there is a difference in the manner of crystal growth and in etching speed between the ITO formed on the interlayer insulating film 6 which is an organic film and the ITO formed on the glass substrate 1 or on an inorganic film. For example, etching speed of the ITO formed on the organic film is faster than that of the ITO formed on the inorganic film by 2 to 5 times. In the actual manufacturing process, from the viewpoint of patterning precision of the picture element electrode, it is necessary to set an etching time to that for the image display section in which the ITO is formed on the interlayer insulating film 6 composed of an organic film. Accordingly, in the terminal region on the guard resistance 7 side where the interlayer insulating film 6 is not formed, there arises a problem that the ITO remains not etched between the adjacent two gate terminals 4, and between two source terminals 5. The ITO left not etched brings about a deficient leak between respective terminals.
To reduce this deficient leak, it was necessary to perform a first etching on the etching condition (at an etching time) applied to the ITO formed on the organic film of faster etching speed, and perform a second etching at an etching time applied to the ITO formed on the glass substrate or on the inorganic film, while protecting the ITO on the organic film with a resist. In this manner, since it is necessary for resist pattern and etching to be performed twice, there is a disadvantage that the manufacturing process becomes unavoidably complicated.
The Japanese Laid-Open Patent Publication (unexamined) No. 90397/1997 discloses a method for etching an ITO film in which by causing an interlayer insulating film to remain between the terminals in assembly region, short circuit between the terminals can be prevented and etching process is performed once.
In the conventional liquid crystal display of above arrangement to achieve a TFT array of high aperture ratio, any interlayer insulating film is not formed in the assembly region for electrical connection between an external substrate provided on the outside of the display region of the TFT array substrate and each electrode line. Therefore, in the step of forming the picture element electrode on the interlayer insulating film, it is essential to perform twice the photomechanical process and the etching process, whereby there arise problems such that manufacturing process becomes complicated, and throughput is lowered while cost being increased.
Moreover, to leave the interlayer insulating film between the terminals, there is a further problem that irregularity due to the interlayer insulating film increases a connection resistance at the time of connecting the terminals to the external substrate.
Generally, the electrical connection between the picture element electrode of the TFT array of above structure and the drain electrode is achieved through the contact hole formed in the interlayer insulating film. In this case, to reduce the connection resistance between the picture element electrode and the drain electrode, after forming the contact hole by dry etching using CF4+O2, SF6+O2 or other fluorine gas+O2, an ashing process is performed using O2 gas to remove residue from the contact hole.
However, as the surface of the interlayer insulating film is also etched in the ashing process using the O2 gas, irregularity is formed on the surface of the interlayer insulating film. It was found that such a surface condition of the interlayer insulating film gives an influence on the etching characteristic (adaptability to etching) of the ITO film formed on the interlayer insulating film.
For example, after the etching process using CF4+O2, SE6+O2 or other fluorine gas+O2, the surface of the interlayer insulating film is smooth. When forming an ITO film on the interlayer insulating film of such a smooth condition, etching speed of the ITO film on the interlayer insulating film is almost the same as that of ITO film on the transparent insulating substrate. Thus the ITO film can be patterned by one etching process. Actually, in the case of performing an etching process at an optimum etching speed of the ITO film on the transparent insulating substrate, a side etching amount of ITO pattern on the interlayer insulating film is 1 xcexcm or less on one side, thus a desirable ITO pattern is obtained.
However, when performing the ashing process using O2 gas after the etching process using CF4+O2, SF6+O2 or other fluorine gas+O2, irregularity is produced on the surface of the interlayer insulating film. When forming an ITO film on the interlayer insulating film of such an irregular surface condition, etching speed of the ITO film on the interlayer insulating film is faster than that of the ITO film on the transparent insulating substrate by 5 times. Therefore, it is impossible to pattern the ITO film by just one etching process. Actually, in the case of performing an etching process at an optimum etching speed of the ITO film on the transparent insulating substrate, a side etching amount of ITO pattern on the interlayer insulating film is 3 xcexcm or more on one side, thus the ITO pattern is formed into an extremely tapered configuration.
As discussed above, in the case of performing the ashing process with O2 gas to reduce the connection resistance between the picture element electrode and the drain electrode, there arises a problem that it is impossible to pattern the ITO film by just one etching process. On the other hand, in the case of not performing any ashing process with O2 gas, there arises another problem that the ITO film on the interlayer insulating film and the ITO film on the transparent insulating substrate can be certainly patterned by just one etching process, but connection resistance between the picture element electrode and the drain electrode is increased.
The present invention was made to solve the above-discussed problems, and has an object of providing a TFT array substrate of high aperture ratio capable of being manufactured in smaller number of processes than that in the prior arts and capable of preventing a leak between terminals due to residue produced by etching ITO. A manufacturing method of the TFT array substrate and a liquid crystal display using the TFT array substrate are also provided.
Another object of the invention is to provide a manufacturing method of a TFT array substrate of high aperture ratio in smaller number of processes than that in the prior arts, without any photomechanical process conventionally required at the time of forming a contact hole at the opposite end of the image display section side of each terminal and a contact hole of guard resistance section, and in which a contact hole of the drain electrode portion in the image display section and a contact hole of each terminal section and guard resistance section can be simultaneously formed on an interlayer insulating film, by providing the interlayer insulating film not only on the image display section of the substrate but also on the peripheral edge section of the substrate including the guard resistance and a short ring for preventing the electrostatic destruction of the TFT at the time of manufacture, at least from opposite end of the image display section side of each terminal in terminal region.
A further object of the invention is to provide a manufacturing method in which pattern formation of a transparent conductive film can be performed by just one resist pattern formation and etching, without leaving any transparent conductive film between terminals, in spite of performing an etching on the etching conditions applied to the transparent conductive film formed on the interlayer insulating film, by providing an interlayer insulating film between terminals in terminal region so that width of the interlayer insulating film is smaller than the distance between the terminals, and in which it is possible to prevent a deficient leak between terminals due to residue produced by etching the transparent conductive film.
A yet further object of the invention is to provide a manufacturing method in which coverage of the transparent conduct film becomes insufficient, due to existence of a sharp step of an insulating film of which section is not tapered between one terminal and another, and which can prevent deficient leak between the terminals, by providing the insulating film wider and thicker than the terminals on a lower layer of each terminal in terminal region.
A still further object of the invention is to provide a manufacturing method of a liquid crystal display in which connection resistance between picture element electrode and drain electrode can be lowered and stabilized, and at the time of forming the picture element electrode, an ITO film can be patterned by just one etching process without occurring any short circuit between the terminals in assembly region.
A further object of the invention is to provide a manufacturing method of a liquid crystal display of high performance and high aperture ratio at a reasonable cost, in which, for manufacturing the liquid crystal display achieving an improvement in aperture ratio by the steps of forming an interlayer insulating film composed of a transparent resin on electrode lines and on a TFT, flattening a surface of the interlayer insulating resin, and forming a picture element electrode on the uppermost layer, any residue on the bottom portion of a contact hole is exactly removed by optimizing dry etching condition for forming the contact hole to which the picture element electrode and a drain electrode formed on the interlayer insulating film are electrically connected, connection resistance between the picture element electrode and the drain electrode can be reduced by achieving a condition that there is no irregularity on the surface of the interlayer insulating film at the time of forming an ITO film forming the picture element electrode after forming the contact hole, and the ITO film on the interlayer insulating film and the ITO film on the transparent insulating substrate exposed between the terminals in the assembly region can be patterned into a desirable configuration without short circuit between the terminals in one etching process.
A TFT array substrate according to the present invention comprises: a plurality of gate lines provided with a gate electrode and formed on a transparent insulating substrate; a plurality of source lines provided with a source electrode and crossing over the gate lines; a semiconductor layer provided on the gate electrode through a gate insulating film; a thin film transistor comprised of the source electrode and the drain electrode connected to the semiconductor layer; an interlayer insulating film formed on the substrate, and of which surface is flattened so as not to produce any step due to the thin film transistor; a picture element electrode composed of a transparent conductive film provided in a wide spread manner on the interlayer insulating film and connected to the drain electrode through a contact hole formed on the interlayer insulating film; and a terminal region in which terminals electrically connected to each of the gate lines and the source lines are arranged on the periphery of an image display section of the substrate to connect each terminal to an external terminal; wherein the interlayer insulating film is provided not only on the image display section side but also on a peripheral edge portion including at least an opposite end of the image display section side of each terminal in the terminal region.
It is preferable that the interlayer insulating film is provided between respective terminals in the terminal region so that width of the interlayer insulating film is smaller than a distance between the terminals.
It is preferable that the interlayer insulating film which is thick and of which section is not tapered is provided between respective terminals in the terminal region so that width of the interlayer insulating film is smaller than the distance between the terminals.
It is preferable that an insulating film which is thick and of which section is not tapered is provided on a lower layer of each terminal in the terminal region so that width of the insulating film is larger than that of the terminals.
It is preferable that the interlayer insulating film is provided on the entire surface of the terminal region.
It is preferable that the interlayer insulating film is composed of a photosensitive resin.
A liquid crystal display according to the invention comprises a liquid crystal arranged between any of the mentioned TFT array substrates and an opposite electrode substrate having a transparent electrode, a color filter, etc.
A manufacturing method of a TFT array substrate according to the invention comprises: a first step of forming lines such as gate lines, source lines and a thin film transistor on a transparent insulating substrate; a second step of forming an interlayer insulating film not only on an image display section of the substrate but also on a peripheral edge section of the substrate, including a guard resistance and a short ring for preventing electrostatic destruction of the thin film transistor at the time of manufacture, at least from opposite end of the image display section side of terminals in a terminal region; a third step of forming contact holes respectively for a drain electrode section, a terminal section and a guard resistance section on the interlayer insulating film; and a fourth step of forming a transparent conductive film such as ITO on the substrate, and forming a picture element electrode, each terminal and the guard resistance by resist patterning and etching.
It is preferable that in the second step, an organic film is used as the interlayer insulating film.
It is preferable that in the second step, a photosensitive resin is used as the interlayer insulating film.
It is preferable that in the fourth step, a resist pattern for each terminal is formed wider than a desired pattern on the interlayer insulating film, and an etching is performed on the etching condition applied to the transparent conductive film formed on a transparent insulating substrate or on an inorganic film.
A manufacturing method of a liquid crystal display according to the invention in which two transparent insulating substrates, at least on either of which an electrode is formed, are adhered facing to each other and a liquid crystal is held between the two transparent insulating substrates comprises: a step of forming a scanning electrode, a scanning electrode line and a scanning electrode line terminal on either of the two transparent insulating substrates; a step of forming an insulating film on the scanning electrode, scanning electrode line and scanning electrode line terminal; a step of forming a semiconductor layer on the scanning electrode through the insulating film; a step of forming a first electrode, a first electrode line and a first electrode line terminal and a second electrode on the semiconductor layer; a step of forming a passivation film on the first electrode, first electrode line, first electrode line terminal and second electrode; a step of forming a contact hole on the second electrode and forming an interlayer insulating film having an aperture in an assembly region in which the scanning electrode line terminal and the first electrode line terminal are formed, by applying a transparent resin having a photosensitivity to the passivation film and by exposure and development thereof; a step of etching the passivation film and the insulating film exposed through the contact hole and the aperture by dry etching using the interlayer insulating film as a mask; and a step of forming a transparent conductive film on the interlayer insulating film, in the contact hole, on the transparent insulating substrates exposed through the aperture, on the scanning electrode line terminal and on the first electrode line terminal, and forming a picture element electrode electrically connected to the second electrode through the contact hole and forming a transparent conductive film pattern on the scanning electrode line terminal and on the first electrode line terminal by patterning in just one etching process; in which surface of the interlayer insulating film after the etching process by dry etching is smooth.
Another manufacturing method of a liquid crystal display according to the invention in which two transparent insulating substrates, at least on either of which an electrode is formed, are adhered facing to each other and a liquid crystal is held between the two transparent insulating substrates comprises: a step of forming a scanning electrode, a scanning electrode line and a scanning electrode line terminal on either of the two transparent insulating substrates; a step of forming an insulating film on the scanning electrode, scanning electrode line and scanning electrode line terminal; a step of forming a semiconductor layer on the scanning electrode through the insulating film; a step of removing the insulating film in an assembly region in which the scanning electrode line terminal and a first electrode line terminal are formed; a step of forming the first electrode, a first electrode line and a first electrode line terminal and a second electrode on the semiconductor layer; a step of forming a passivation film on the first electrode, on the first electrode line, first electrode line terminal and second electrode; a step of forming a contact hole on the second electrode and forming an interlayer insulating film having an aperture in an assembly region in which the scanning electrode line terminal and the first electrode line terminal are formed, by applying a transparent resin having a photosensitivity to the passivation film and by exposure and development thereof; a step of etching the passivation film exposed through the contact hole and the aperture by dry etching using the interlayer insulating film as a mask; and a step of forming a transparent conductive film on the interlayer insulating film, in the contact hole, on the transparent insulating substrates exposed through the aperture, on the scanning electrode line terminal and on the first electrode line terminal, and forming a picture element electrode electrically connected to the second electrode through the contact hole and forming a transparent conductive film pattern on the scanning electrode line terminal and on the first electrode line terminal by patterning in just one etching process; in which surface of the interlayer insulating film after the etching process by dry etching is smooth.
A further manufacturing method of a liquid crystal display according to the invention in which two transparent insulating substrates, at least on either of which an electrode is formed, are adhered facing to each other and a liquid crystal is held between the two transparent insulating substrates comprises: a step of forming a scanning electrode, a scanning electrode line and a scanning electrode line terminal on either of the two transparent insulating substrates; a step of forming an insulating film on the scanning electrode, scanning electrode line and scanning electrode line terminal; a step of forming a semiconductor layer on the scanning electrode through the insulating film; a step of forming a first electrode, a first electrode line and a first electrode line terminal and a second electrode on the semiconductor layer; a step of forming a passivation film on the first electrode, first electrode line, first electrode line terminal and second electrode; a step of forming a contact hole on the second electrode and forming an interlayer insulating film having an aperture in an assembly region in which the scanning electrode line terminal and the first electrode line terminal are formed, by applying a transparent resin having a photosensitivity to the passivation film and by exposure and development thereof; a step of forming a resist by applying a photo-resist and patterning the photo-resist into the same configuration as the interlayer insulating film; a step of removing the resist after etching the passivation film and the insulating film exposed through the contact hole and the aperture by dry etching using the resist as a mask; and a step of forming a transparent conductive film on the interlayer insulating film, in the contact hole, on the transparent insulating substrates exposed through the aperture, on the scanning electrode line terminal and on the first electrode line terminal, and forming a picture element electrode electrically connected to the second electrode through the contact hole and a transparent conductive film pattern on the scanning electrode line terminal and on the first electrode line terminal by patterning in just one etching process.
A still further manufacturing method of a liquid crystal display according to the invention in which two transparent insulating substrates, at least on either of which an electrode is formed, are adhered facing to each other and a liquid crystal is held between the two transparent insulating substrates comprises: a step of forming a scanning electrode, a scanning electrode line and a scanning electrode line terminal on either of the two transparent insulating substrates; a step of forming an insulating film on the scanning electrode, scanning electrode line and scanning electrode line terminal; a step of forming a semiconductor layer on the scanning electrode through the insulating film; a step of forming a first electrode, a first electrode line and a first electrode line terminal and a second electrode on the semiconductor layer; a step of forming a passivation film on the first electrode, first electrode line, first electrode line terminal and second electrode; a step of forming an interlayer insulating film by applying a transparent resin having no photosensitivity to the passivation film; a step of forming a resist, and removing the resist after forming a contact hole on the second electrode and an aperture in an assembly region in which the scanning electrode line terminal and the first electrode line terminal are formed, by etching the interlayer insulating film, passivation film and insulating film by dry etching; and a step of forming a transparent conductive film on the interlayer insulating film, in the contact hole, on the transparent insulating substrates exposed through the aperture, on the scanning electrode line terminal and on the first electrode line terminal, and forming a picture element electrode electrically connected to the second electrode through the contact hole and forming a transparent conductive film pattern on the scanning electrode line terminal and on the first electrode line terminal by patterning in just one etching process.
It is preferable that the insulating film in the assembly region in which the scanning electrode line terminal and the first electrode line terminal are formed is removed after forming the semiconductor layer and before forming the first electrode, the first electrode line, the first electrode line terminals and the second electrode.
It is preferable that in the etching process by dry etching using the inter layer insulating film as a mask, an ashing process using O2 gas and a second etching process using CF4+O2, SF6+O2 or other fluorine gas+O2 gas are performed, after completing a first etching process using CF4+O2, SF6+O2 or other fluorine gas+O2 gas.
It is preferable that in the second etching process using CF4+O2, SF6+O2 or other fluorine gas+O2 gas, the etching process is performed in a shorter time or by setting a flow ratio of O2 gas to be higher or by setting a power to be smaller than that in the first etching process using CF4+O2, SF6+O2 or other fluorine gas+O2 gas, or by combining at least two of these process conditions.
It is preferable that in etching process conditions by dry etching after forming the resist on the interlayer insulating film, after the etching process using CF4+O2, SF6+O2 or other fluorine gas+O2 gas, an ashing process using O2 is performed.
It is preferable that in the etching process using the interlayer insulating film or the resist as a mask, the second etching process using CF4+O2, SF6+O2 or other fluorine gas+O2 gas is performed by setting a flow ratio of O2 gas to be higher than that in the first etching process, after completing the first etching process using CF4+O2, SF6+O2 or other fluorine gas +O2 gas. | {
"pile_set_name": "USPTO Backgrounds"
} |
(1) Field of the Invention
This invention relates to cleaning valves in fluid handling systems and more particularly to an independently actuated reciprocating rod.
(2) Description of the Prior Art
Flow transmitters and flow measuring devices are often connected by valves to process pipes. Foreign matter and debris periodically block the duct connecting these valves to the conduit. This debris could be a waxy substance: tars, coke, pulp, powders from slurries, etc. My U.S. Pat. No. 4,192,342 shows the telescoping of a cleaning rod within a hollow stem and forcing the rod through the duct to clean debris. That patent discloses a permanent cleaning rod to be used in every duct which requires cleaning. This is expensive in large process plants. In addition the telescoped rod may be unexpectedly unscrewed, allowing the loss of the fore end of the tool and consequent release of process fluid when the remaining rod-out tool is withdrawn. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to a side channel blower, especially for use as a combustion air blower in vehicle heaters, with a blower housing forming at least one side channel, in which one intake opening and one exhaust opening terminate, as well as with a blower wheel provided with a plurality of blades disposed immediately adjacent to the side channel.
Such blowers are known to have the disadvantage of developing a considerable amount of noise. In order to combat this, the installation chamber of the blower has been lined with noise-absorbing material or large volume intake mufflers. These measures are costly, however, and require a great deal of space, if the noise is to be reduced to a tolerable level, e.g., a value of approximately 60 dB(A) or less.
A principle object of the invention, therefore, is to provide a side channel blower with reduced noise emission.
This object is achieved according to a preferred embodiment of the invention by virture of the fact that at least the edge of the intake opening, which is located rearward in the rotational direction of the blower wheel, is made elastic.
To explain the source of the noise generation problem and the manner in which the present invention reduces same, the process by which gas, e.g., air, is delivered by a blade chamber located between two blades of the blower wheel during one complete revolution of this wheel will now be described. Firstly, the blade chamber draws in the gas at the intake opening. Pressure is generated in the blade chamber and, as soon as the blade chamber reaches to outlet opening, gas is released through this opening. However, during its movement from the intake opening to the exhaust opening, the blade chamber is always under pressure. Thus, when the leading edge, in the rotational direction, of the blade chamber reaches the rear edge of the intake opening, in the rotational direction of the blower wheel, gas suddenly escapes from the blade chamber under pressure. This produces a pressure pulse which enters the environment. This process is repeated for each individual blade. The resultant pressure pulse train is the basic reason for the disturbing noise generation. The measure according to the present invention gradually reduces the pressure in the individual blade chambers as these chambers move toward the outlet opening by virtue of deflection of the elastic trailing edge. This is because the gas can escape from the blade chamber with less of an impact, so that the pressure decline in the blade chamber is produced gradually instead. In this way, the compression impacts upon the environment are considerably reduced.
The elastic edge of the intake opening may be formed in an especially simple fashion from a plate of elastic material inserted in the blower housing. In particular, the plate can be made of sponge rubber, soft foam rubber, or a thin piece of sheet metal mounted partially on the blower housing.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a single embodiment in accordance with the present invention. | {
"pile_set_name": "USPTO Backgrounds"
} |
Brazed rotary cutting tools include, but are not limited to: endmills, router bits, shapers, drills, reamers, counterbores, countersinks, and taps. In designing and using such cutting tools, significant attention is paid to both the wear resistance and to the dimensional precision of a tool. As a result, significant efforts are made to improve those characteristics, while constraining any cost increases such improvements might have upon the construction price of the cutting tools.
Wear resistance is typically affected by the material that forms the cutting surface of the tool, the geometry of the cutter, and the material being cut. Cutter wear is typically measured by monitoring specific changes in the cutting edge of the tool. As the tool experiences wear, the cutting edge will begin to break down and exhibit a loss of cutting edge material. Such loss may be exhibited by the formation of a wear radius on the cutting edge and/or by the loss of larger chunks of cutting edge material through chipping or other destructive means. Over time, material suppliers have developed new or improved materials which reduce the rate of cutter wear. Manufacturers have dramatically reduced wear in many applications by moving from high-carbon steel, to high-speed steel, to carbide, and finally to diamond products such as polycrystalline diamond (“PCD”). However, this increased wear resistance comes at the price of increased material costs and manufacturing difficulties.
Diamond has proven to be an extremely wear resistant tool material, especially for machining advanced, but abrasive, composite materials such as carbon fiber and aramids. However, unlike steel and carbide, the high cost and difficult working characteristics of diamond prevent its use as a both a structural body material and a cutting edge material. Instead, diamond tools are typically of a two piece design in which one material acts as the tool body and a segment of PCD is situated only at the cutting edge. While this is the common structure of PCD cutting tools, manufacturers still find it difficult to attach diamond directly to the tool body material and to thereafter shape it to the desired cutting edge profile.
To solve the attachment problem, manufacturers have resorted to a number of construction methods. In one exemplary method, manufacturers fix thin slabs of diamond to thicker carbide disks, where the carbide serves as a backer material supporting the brittle diamond structure. Controlled atmosphere brazing is one common method of fixing the diamond to the carbide slug. Another common method is the pressing and then sintering of a carbide and diamond composite compact.
In FIG. 1, a commercially available PCD and carbide disk 100 is shown. The disk consists of a wear layer 101 of PCD typically ranging in thickness from 0.005″ to 0.125″, and most typically from 0.010″ to 0.040″. It is known by those skilled in the art that the wear layer 101 may instead consist of a layer of polycrystalline cubic boron nitride (“PCBN”). The PCD layer 101 is permanently bonded to a carbide layer 102, where the carbide consists primarily of tungsten carbide and various other compounds which are used as binders or to impart specific properties such as toughness or hardness to the carbide layer.
Using the PCD and carbide disk 100 as raw material stock, an insert manufacturer will typically cut or grind specifically shaped cutting tool inserts from the disk 101. Most often, the insert manufacturer will use electrical discharge machining (“EDM”) to cut the insert from the disk 100. For purposes of illustration, a representation of a portion of an EDM wire 103 is shown passing through the disk 100 at an angle 104.
FIG. 2 is a top view of the PCD and carbide disk 100 showing EDM cut paths for an exemplary insert shape. The EDM wire 103 may be used to form a flat faced insert illustrated by the EDM cut pattern 201. One skilled in the art will understand that other methods, such as grinding, may also be used to form an insert from the disk 100.
FIG. 3 shows a perspective view of an exemplary flat face insert 300 formed from the PCD/carbide disk 100. The insert 300 is cut in such a manner that a straight cutting edge 301 is formed at the interface of the flat rake face 303 and the flat relief surface 304. The EDM cut path results in a straight bottom edge 302 at the base of the rake face 303. Typically, a portion of the insert 305 may be removed from the back bottom corner of the insert. This portion 305 is removed by any practical material removal process, such as grinding or EDM, and the resulting angle 306 is typically formed at substantially 90 degrees in order to facilitate later mounting of the insert 300 in a fluted tool body.
Angle 307 of the insert is known as the included angle and is defined herein as the angle formed substantially at the cutting edge 301 and between the rake face 303 and the relief surface 304. The included angle 307 may typically be less than 90 degrees. The benefit of having an included angle 307 of less than 90 degrees is that the insert may be mounted to a tool body and no further material must be removed to create an appropriately shaped relief surface 304 behind the cutting edge. FIGS. 7 and 8, discussed later in relation to aspects of the invention, illustrate the location of the relief surface in more detail.
Typically, the cut pattern 201 in the disk 100 is oriented such that wear layer 101 forms the relief surface 304. This is done so that a wear resistant cutting edge 301 is produced with minimal use of the expensive wear layer material. In an alternative configuration, where the wear layer 101 is oriented to form the rake face (configuration not shown), the cutting edge may still be wear layer material; however, more wear layer material is required to cover the large rake face and, consequently, the insert is more expensive to produce. In either configuration, a significant portion of either or both the rake face and the relief surface consist of wear layer material.
Once the insert 300 is produced, one or more of the inserts 300 are mounted to a cutting tool body in order to create a semi-finished tool. One carbide surface of the insert 300 is typically oriented towards the mounting interface with the tool body, as shown with reference to FIGS. 4A and 4B. Brazing is the common method of fixing the insert to the tool body. The semi-finished tool is then subject to some form of material removal process, such as grinding or electrical discharge machining (“EDM”), where the cutting edge is brought to the desired condition, shape, and dimensions.
A problem with this method for producing PCD (or PCBN) edged cutting tools is that carbide and diamond inserts warp during the brazing process that fixes them to the tool body. PCD and carbide typically exhibit different coefficients of thermal expansion. During the brazing process, the high temperature used to melt the silver solder or other brazing material causes the PCD and carbide sections of the insert to expand at different rates. As a result, the insert warps in one or more dimensions. This warpage causes numerous problems. First, the warped surfaces will change the dimensional characteristics of the assembled tool, thereby necessitating allowances for additional grinding stock to compensate for high and low spots on the rake face and relief surface. Second, warpage can result in the insert rocking against the bottom mounting surface of a fluted tool body during or before brazing, resulting in difficulty maintaining alignment of the insert to the tool. Third, PCD is extremely difficult to machine. Significant cost is attributable to the removal of excess grinding stock from the assembled tool by traditional EDM or tool grinding methods.
To illustrate the problems cause by braze-induced warping of the insert, FIG. 4A shows an endmill type rotary cutting tool 400 with exemplary flat faced insert 300 mounted in a cutting tool body 406. Normally, the insert 300 is seated such that its flat bottom edge 302 is in contact with the bottom of the flute, thus helping to align the cutting edge 301 to within some desired level of concentricity, taper, and/or runout to the cutting tool 400 and/or to other cutting edges present on the cutting tool.
As previously stated, the common means for attaching insert 300 to the tool body 406 is by brazing. During brazing, flux and silver solder or other appropriate materials are placed between the insert 300 and the tool body 406. The assembly is then heated to a high temperature using a torch or induction heating methods. The assembly is heated to the point that the silver solder melts and bonds the insert 300 to the tool body 406. A known problem is that the heating of the insert 300 can cause it to permanently warp due to the different coefficients of thermal expansion between the insert's 300 wear layer and carbide layer.
Two specific problems of insert warping are illustrated in FIG. 4B. First, during the heating and cooling associated with brazing the insert 300 to the tool body 406, the PCD and carbide expand at different rates and the insert 300 becomes deformed, as shown by the post-braze insert 409. As a result of the insert warpage, the cutting edge 401 may exhibit a curved shape. The cutting edge corners, such as corner 411, may circumscribe a larger cutting edge diameter than the diameter circumscribed by the middle of the cutting edge 412.
The amount of warp, approximated as dimension 404 in this view, is measured as the diametric radial distance between the high corner 411 and the low center point 412. Diametric radial distance is defined herein as the radial distance between the circles circumscribed by two points, where the circles are approximately concentric to the axis of rotation of the tool. Though the amount of cutting edge warp 404 depends on numerous factors, including, but not limited to, the composition of the PCD layer, the composition of the carbide layer, the heating method, and the length of the insert, the amount of warp 404 is generally predictable, repeatable, and within a narrow band of variance for most commercially available carbide and PCD disk 100 compositions and insert sizes.
Braze induced insert warpage of a flat face insert creates a cutting edge profile that may exhibit substantial problems with concentricity, taper, and/or runout due to the movement of various portions of the post-braze cutting edge 401 from the straightness of the pre-braze cutting edge 301. Similar problems exist for shape face inserts. As a result, the cutting edge tolerances of the finished tool must either be loosened to accommodate these warp effects or, more commonly, additional material removal operations must be performed on the cutting edge 401 after the inserts are brazed to the tool. These additional finishing operations are undesirable because current material removal processes are not well suited for the work. Grinding operations using diamond superabrasive wheels are slow when used for grinding hard polycrystalline diamond cutting edges and EDM machines are also slow when performing finishing work on rotary cutting tools.
A second problem associated with braze-induced insert warpage is illustrated by the insert's warped bottom edge 402. This edge, along with the entire bottom insert surface, warps similarly to the cutting edge, though the amount of bottom edge warp 405 may be greater or less than the amount of cutting edge warp 404. This bottom warp can result in a single point of contact 408 at the interface between the bottom of the flute 407 and the bottom edge of the insert 402. Compared to a normally flat interface, such as between the pre-braze bottom edge 302 and the bottom of flute 407 in FIG. 4A, this single point of contact 408 allows the insert 409 to shift or rock back and forth within the flute 407 during brazing. Consequently, it is difficult to maintain accurate positioning of the insert 409 relative to the tool body 406. This further contributes to problems of concentricity, taper, and/or runout and again requires looser tolerances or additional material removal operations after brazing. | {
"pile_set_name": "USPTO Backgrounds"
} |
(1) Field of the Invention
This invention relates to a solenoid valve for controlling the flow of pressurized fluid in, e.g., an antilock control device of an automotive brake.
This type of solenoid valve is provided in a pressure oil passage to open and close the passage according to instructions from a computer.
(2) State of the Prior Art
FIG. 2 shows a conventional solenoid valve of this type. It comprises a cylindrical frame 21, a valve seat 23 fitted in a small-diameter hole 22 formed in the upper part of the frame 21, an armature 25 mounted in an intermediate-diameter hole 24 formed in the frame 21 under the small-diameter hole 22, and an electromagnetic coil 27 mounted on the inner wall of a large-diameter hole 26 formed in the frame 21 under the intermediate-diameter hole 24. Also, a sleeve 28 having an inner diameter larger than the diameter of the armature 25 is mounted on the armature in the intermediate-diameter hole 24. A yoke 29 is inserted in the sleeve 28 from its bottom.
The contact portions between the small-diameter hole 22 and the valve seat 23, between the intermediate-diameter hole 24 and the sleeve 28 and the between the sleeve 28 and yoke 29 (designated a, b and c in FIG. 2) are sealed, e.g. by welding. Thus, a pressure oil chamber 31, in which is mounted the armature 25, is sealed except for an inlet/outlet port for pressure oil and a hole 32 formed through the side wall of the frame 21.
The armature 25 is movable up and down in the pressure oil chamber 31 and is urged upwards by a coil spring 45. Thus, the pressure oil inlet/outlet port of the valve seat 23 is normally closed by a valve body 33 provided on the top end of the armature 25.
The frame 21, armature 25 and yoke 29 are made of a magnetic material. These magnetic parts and the electromagnetic coil 27 form a magnetic circuit. When the electromagnetic coil 27 is excited, the armature 25 descends, separating the valve body 33 from the valve seat 23. The pressure oil inlet/outlet port is now opened.
On the other hand, the frame 21 is inserted in a hole 35 formed in a housing 34, which may be a component part of an antilock control device. The yoke 29 is in contact with a housing cover 36. In this way, the solenoid valve is mounted on an antilock control device.
The housing 34 has a first pressure oil inlet/outlet port 37 communicating with the small-diameter hole 22 of the frame 21 and a second pressure oil inlet/outlet port 38 communicating with the hole 32 formed in the frame 21. Thus, a pressure oil passage is formed between the first and second pressure oil inlet/outlet ports 37 and 38, extending through the pressure oil chamber 31. This pressure oil passage is closed while the oil pressure inlet/outlet port of the valve seat 23 is closed. It is opened when the electromagnetic coil 27 is excited and the pressure oil inlet/outlet port of the valve seat 23 opens.
The frame 21 has on the outer peripheral surface thereof two grooves 41 and 42 carrying O-rings 43 and 44, respectively. The O-ring 43 serves to close the fluid communication between the first pressure oil inlet/outlet port 37 and the small-diameter hole 22. The communication between the second pressure oil inlet/outlet port 38 and the hole 32 is closed by both O-rings 43 and 44. The other ring 44 serves to seal the passage between the second pressure oil inlet/outlet port 38 or the hole 32 and the outside.
Another solenoid valve of this type is disclosed in Japanese Unexamined Utility Model Publication 63-99081 filed by the present applicant.
Such conventional solenoid valves require many seals such as seals for portions a), b) and c) and O-rings 43 and 44. Thus, such conventional valves need O-rings for a liquid-tight seal or an additional welding step. Otherwise, a finishing step has to be added so that a sufficiently liquid-tight seal is obtainable simply by press-fitting. This increases the cost and makes it difficult to reduce the size of the valve. | {
"pile_set_name": "USPTO Backgrounds"
} |
Communications systems may use radio-frequency (RF) electromagnetic signals to communicate information. The RF electromagnetic signals used for communication may include free-space radio waves propagating in air, guided electromagnetic waves propagating in coaxial cable, or both. A concept of so-called “frequency reuse” allows cable operators to reuse the air RF frequencies by carrying within the cable networks signals at frequencies overlapping with the air RF frequencies. The frequency reuse is made possible by the electromagnetic shielding effect exhibited by coaxial cables.
In bidirectional cable networks, upstream, i.e. towards the headend, and downstream, i.e. away from the headend, signals occupy separate frequency bands called upstream and downstream spectral bands. In the United States, the upstream spectral band typically spans from 5 MHz to 42 MHz, while the downstream spectral band typically spans from 50 MHz to 1000 MHz. Together, the upstream and downstream spectral bands overlap a so-called Very High Frequency (VHF) band spanning between 30 MHz and 300 MHz. Downstream spectral band also partially overlaps a so-called Ultra High Frequency (UHF) band spanning between 300 MHz and 3 GHz.
Ideally, cable network signals do not interfere with the over-the-air signals. However, when the cable shielding, or shielding of cable network components is degraded or compromised for some reason, e.g. improper installation, rodent chews, etc., electromagnetic signals propagating in the cable network may leak out to the over-the-air environment, and vice versa. If the leakage field is sufficiently strong, interference between over-the-air and guided electromagnetic waves may occur, causing service quality degradation in over-the-air communications, cable communications, or both. The impact of signal leakage on over-the-air users may, depending on the ratio of the desired signal strength to the leakage strength and other factors, cause a mild or moderate degradation, or may even cause a complete signal disruption in extreme cases.
Licensed over-the-air users must be able to operate without interference degrading or disrupting their services. Paragraph 76.613 of Telecommunications Chapter I of Federal Communications Commission (FCC) states: “An MVPD that causes harmful interference shall promptly take appropriate measures to eliminate the harmful interference.” If a leakage-related interference occurs, the operator of the cable network causing the leakage must fix the problem. In cases where the interference may impact “safety of life and protection of property”, the FCC has an authority to require a cable operator to shut down offending signals until the problem has been resolved. Clearly, this represents a serious concern for cable network operators.
Although FCC Rules specify signal leakage limits over a wide range of frequencies, the emphasis is made in the Rules on the aeronautical band spanning between 108 MHz and 137 MHz, which is within the VHF band. This is perhaps why the signal leakage has been historically monitored mostly in the aeronautical band. Furthermore, the assumption has been that absence of leakage in the aeronautical band indicates the likely absence of leakage at other frequencies as well.
Recently, new data has emerged indicating that some frequencies may be radiated much more efficiently from a leakage location than others. Depending on the nature and geometry of the leak, there may be little VHF leakage and significant UHF leakage, and vice versa. Thus, UHF leakage still needs to be measured, even when the VHF leakage is measured. Measuring UHF leakage has become increasingly important in view of a growing cellular network usage, in particular in Long Term Evolution (LTE) spectral band. The LTE band spans between 698 MHz and 960 MHz, which is in the UHF frequency band. UHF leakage in the 470-698 MHz range may affect antenna-based TV reception and some non-TV services that may exist in the 470-698 MHz range.
For technical reasons, measuring leakage in the UHF band has proven much more difficult than in the VHF band. To provide adequate sensitivity, the VHF leakage has typically been monitored using a resonant antenna tuned to an injected “tag” signal having a very narrow bandwidth of 10-15 KHz. Digitally-modulated UHF leaking signals are much broader in bandwidth than 10-15 KHz, and often appear noise-like in a frequency spectrum. For instance, quadrature amplitude modulated (QAM) signals occupy 6 MHz or 8 MHz frequency band per channel, and there may be many (up to a hundred or more) leaking downstream QAM channels in the UHF band, increasing the total radiated bandwidth to tens, and perhaps hundreds of megahertz. Because of this, UHF signals are more difficult to detect than VHF signals.
One known approach to monitoring cable network signal leaks in the UHF band is to provide a narrowband UHF pilot signal between two active QAM carrier signals, preferably at a lower level than the adjacent active carriers, to avoid disturbing the latter; and to provide field test equipment tuned to detect the pilot signal. Thus, the pilot signal operates as an indicator of signals leaked from a cable network under test. The field test equipment may be outfitted with global positioning system (GPS) locators for automatic mapping of the pilot signal detected in the field, as a truck carrying the test equipment is driven in vicinity of the cable network. Detrimentally, this method requires modification of the downstream cable signal at the headend of the cable network, which may be expensive to implement. Furthermore, the leaking signal in the UHF band may be highly frequency dependent. Therefore, the strength of a narrowband pilot signal may not always be representative of the strength of an actual leaking downstream cable signal.
Another approach to monitor UHF signal leaks in a cable network includes disposing a detector proximate a QAM modulator source for sampling the source QAM signal. These samples are then transmitted to a field device, which compares off-air measured signals to the received samples by computing, in real time, a time-domain correlation function. If the source samples and field samples match, then the signal is identified as leaking out of the cable network. Although this approach does not require pilot signals, in that the QAM signal itself is used as a “pilot” signal, this approach does require a modification of the headend equipment. Furthermore, field test equipment needs to be upgraded with test devices including complex digital signal processors and correlators, to determine a real-time match of QAM time traces. This makes the testing solution based on signal correlation rather costly, as well.
Yet another approach to monitor UHF signal leaks in a cable network includes obtaining and displaying a frequency spectrum of electromagnetic waves in vicinity of a suspected leakage location, to assist a field technician in visually determining if the detected signals resemble QAM signals of a cable network. Although simpler and less expensive than the previously described methods, this method of cable signal leak detection relies on the field technician's knowledge and ability to interpret complex frequency spectra of detected radio waves, which requires extensive training, and may impact veracity and reliability of the test results obtained. Adding to the complexity of relying on visual cues, off-air QAM signals displayed on a frequency spectrum may rarely resemble QAM signals propagating in coaxial cable lines. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a device for opening flexible containers.
It is well known that drinks for human consumption, in particular fruit juices and dietary complements, are ever more frequently sold and preserved inside flexible containers, commonly called “pouches”.
Specifically, such containers comprise a flexible pouch, generally made of polyethylene, and a spout, able to allow the outflow of the product preserved within the container.
The outflow of the product is made particularly convenient by the possibility of exerting an adequate pressure on the drink, squeezing the pouch.
Flexible containers, or pouches, are obtained from a pair of polyethylene sheets peripherally sealed to each other and having an inlet adapted to allow the filling of the container with the desired drink.
In correspondence with the aforesaid inlet is inserted and secured, by sealing, a portion of the spout. In particular, said sealing operation involves the edges of said inlet and is performed by heating means which cause a partial melting of the edges themselves, causing them to adhere to the portion of the spout inserted into the pouch.
The insertion of the spout into said inlet takes place before the container is filled.
A particularly acute problem in the pouch filling sector concerns the opening of the pouches, to allow the insertion of the spout.
The opening of the flexible containers is particularly difficult because the polyethylene sheets tend to adhere to each other, by effect of their reduced thickness and of electrostatic attraction.
This problem has been confronted and partially solved by the apparatus disclosed in the document U.S. Pat. No. 4,182,094, in which a plurality of suction cups are used to open a flexible container.
Specifically, three suction cups are located on a movable head, whilst a pair of suction cups is positioned and buried within a support plane.
The flexible container is interposed between the suction cups installed on the movable head and the suction cups buried within the support plane.
The suction cups present on the movable head are set side by side and mutually aligned, so that two lateral suction cups and a central suction cups can be identified. In particular, the central suction cup is of the bellows type and its grip plane can thus move rearwards relative to the grip plane defined by the remaining pair of suction cups, allowing a flexion of the container which favours the entry of air into the container, thereby facilitating its opening.
The apparatus summarily described above has the important drawback that it does not operate continuously, but it is an apparatus in which the containers to be treated are fed at successive time intervals. Moreover, the arrangement of the suction cups shown in said apparatus is absolutely not adaptable to an apparatus with continuous feeding of the containers, especially to an apparatus in which the containers to be treated are positioned on a rotary carrousel.
Secondly, the flexion of the pouches during the opening phase is strongly conditioned by the efficiency of the bellows suction cup. If said suction cup does not effectively adhere to the pouch, the latter is not able to flex to such an extent as to allow the entry of a sufficient quantity of air to allow its opening. | {
"pile_set_name": "USPTO Backgrounds"
} |
I. Technical Field
The embodiments described herein relate generally to computer modeling and management of electrical power systems and, more particularly, to a simplified way to model a topology of an electrical power system.
II. Background
Computer models of complex systems enable improved system design, development, and implementation through techniques for off-line simulation of system operation. That is, system models can be created on computers and then “operated” in a virtual environment to assist in the determination of system design parameters. All manner of systems can be modeled, designed, and operated in this way, including machinery, factories, electrical power and distribution systems, processing plants, devices, chemical processes, biological systems, and the like. Such simulation techniques have resulted in reduced development costs and superior operation.
Design and production processes have benefited greatly from such computer simulation techniques, and such techniques are relatively well developed, but they have not been applied in real-time, e.g., for real-time operational monitoring and management. In addition, predictive failure analysis techniques do not generally use real-time data that reflect actual system operation. Greater efforts at real-time operational monitoring and management would provide more accurate and timely suggestions for operational decisions, and such techniques applied to failure analysis would provide improved predictions of system problems before they occur.
That is, an electrical network model that can age and synchronize itself in real-time with the actual facility's operating conditions is critical to obtaining predictions that are reflective of the system's reliability, availability, health and performance in relation to the life cycle of the system. Static systems simply cannot adjust to the many daily changes to the electrical system that occur at a facility (e.g., motors and pumps switching on or off, changes to on-site generation status, changes to utility electrical feed . . . etc.) nor can they age with the facility to accurately predict the required indices. Without a synchronization or aging ability, reliability indices and predictions are of little value as they are not reflective of the actual operational status of the facility and may lead to false conclusions. With such improved techniques, operational costs and risks can be greatly reduced.
For example, mission critical electrical systems, e.g., for data centers or nuclear power facilities, must be designed to ensure that power is always available. Thus, the systems must be as failure proof as possible, and many layers of redundancy must be designed in to ensure that there is always a backup in case of a failure. It will be understood that such systems are highly complex, a complexity made even greater as a result of the required redundancy. Computer design and modeling programs allow for the design of such systems by allowing a designer to model the system and simulate its operation. Thus, the designer can ensure that the system will operate as intended before the facility is constructed.
As with all analytical tools, predictive or otherwise, the manner in which data and results are communicated to the user is often as important as the choice of analytical tool itself. Ideally, the data and results are communicated in a fashion that is simple to understand while also painting a comprehensive and accurate picture for the user. For example, graphical displays (e.g., two-dimensional and three-dimensional views) of the operational aspects of an electrical system greatly enhances the ability of a system operator, owner and/or executive to understand the health and predicted performance of the electrical system.
Moreover, the ability to predict, and understand the health and stability of an electrical network (the capability of a power system to maintain stability and/or recover from events and disturbances without violating system operational constraints) in both static and in real-time, is important in order to insure that the power distribution system can meet the power demands and maintain sufficient active and reactive power reserves to hand the ongoing changes in demand and disturbances to the system due to various contingencies. Traditional transient stability programs are capable of accurately computing the trajectories of power system quantities, such as voltages, frequencies, power flow, etc., following disturbances. However, programs leave the understanding of these trajectories, i.e., severity of these disturbances, and their relevance to the power system security largely to an engineer's judgment.
Conventional approaches to modeling complex network topologies, their interconnectivity, interdependencies and relationships are limited to the application of diagrammatic sketches, computer aided design (CAD), or other forms of design technologies that require extensive training and know-how by the user in order to design realistic and error free networks, such as electrical one-line diagrams for power system simulation. As such, there is a need for novel methods that provide intuitive modeling paradigms that reduce the need for end user training or know-how for properly modeling, connecting and defining electrical power transmission, or distribution networks. | {
"pile_set_name": "USPTO Backgrounds"
} |
This application claims the benefit of the People's Republic of China Application No. 201110270292.7, filed on Aug. 17, 2011. | {
"pile_set_name": "USPTO Backgrounds"
} |
Hearing instruments have over the later years been increasingly able to communicate with the surroundings, including communicating with remote controls, spouse microphones, other hearing instruments and lately also directly with smart phones and other external electronic devices.
Hearing instruments are very small and delicate devices and to fulfil the above requirements, the hearing instruments need to comprise many electronic and metallic components contained in a housing small enough to fit in the ear canal of a human or behind the outer ear. The many electronic and metallic components in combination with the small size of the hearing instrument housing impose high design constraints on the radio frequency antennas to be used in hearing instruments with wireless communication capabilities.
Moreover, antennas, typically radio frequency antennas, in the hearing instruments have to be designed to achieve a satisfactory battery lifetime, good communication for all sizes and shapes of heads, ears and hair, in all environments and with as large frequency bandwidth as possible despite the space limitation and other design constraints imposed by the size of the hearing aid. | {
"pile_set_name": "USPTO Backgrounds"
} |
Previously, in magnetic recording technology, increasingly higher data densities have been stored on disk drives using what is known as longitudinal recording techniques. As seen in FIG. 3 (Prior Art), in longitudinal recording the magnetization on the recording medium is switched between lying parallel and anti-parallel to the direction in which the write head is moving in relation to the surface. Although increases in areal densities of nearly 100 percent every year or two for the last several years have been achieved with longitudinal techniques, it is believed that the superparamagnetic limit is beginning to limit the capacities of this kind of recording. As a result, perpendicular recording is being adopted by many manufacturers to find ways to further increase areal density. In perpendicular recording, instead of “lying down” as it were, in same plane as the disk or magnetic surface, the bits are recorded “perpendicularly” in the magnetic surface. This enables much higher recording densities.
Perpendicular recording enables the use of media with higher coercivity. The write heads used to record data perpendicularly must generate much stronger magnetic fields as a result. The higher the coercivity, the more thermally stable and therefore, the less likely the medium is to succumb to superparamagnetic effect at higher than present recording densities. However, at the same time, this means that many of the conventional methods of measuring the magnetic properties of recording media may be inadequate for perpendicular recording applications, as they may not have sufficient magnetic field strength to switch the higher coercivity media.
Perpendicular recording media typically consist of at least a perpendicular recording layer and a soft magnetic underlayer (SUL). To switch magnetization in the perpendicular recording layer, a sufficient perpendicular magnetic field has to be applied. As seen in FIG. 5 (Prior Art) in a perpendicular hard disk drive, this is done with a microscopic single pole tip (SPT) write head 30 at near contact distance (of the order of 10 nanometer). In this situation, the SUL 12 functions as a magnetic flux feedback path for the SPT head, practically doubling the field of the head by the magnetic image effect.
For disk testers in line with production machines, a flying SPT head on a spin stand is not practical. At this point one needs to know the macroscopic magnetic properties such as MRT and HR for immediate process feedback. These properties need to be measured with great accuracy and repeatability (both fractions of a percent), over a large area of the disk, and it has to be done quickly (of the order of 1 disk per minute). For this purpose a macroscopic recording head is a good solution. Current art for longitudinal macroscopic disk measurement uses for example macroscopic heads of 2.5 mm wide, positioned at approximately 25-100 micrometer from the disk. The head is not actually flying, it is positioned to a predetermined distance. Typically 3 tracks are measured, an outer diameter (OD), middle diameter (MD) and inner diameter (ID) track.
For a perpendicular tester with a macroscopic SPT write head, the soft underlayer is too thin to function as a magnetic flux feedback. The soft underlayer is typically less than 1 micrometer thick and therefore can not carry the flux from a core that is orders of magnitude larger. Without the flux feedback through the SUL, the perpendicular magnetic field strength of a macroscopic perpendicular SPT head is limited, and may not be enough to even write the perpendicular media. This is particularly true as it is expected that over the coming years, coercivity will creep up in order to enhance thermal stability of ever smaller magnetic bits. Furthermore, for a macroscopic tester to function properly, it has to be able to not only switch the magnetization, but also to drive fields high enough to achieve maximum remanence, typically at least 2.2× larger than coercivity.
The principle of a macroscopic head residing altogether on one side of a disk has worked in the past for longitudinal magnetic inspection and measurement equipment. However for perpendicular testing and inspection equipment this approach yields insufficient magnetic field perpendicular to the disk. | {
"pile_set_name": "USPTO Backgrounds"
} |
So-called universal boilers with common furnaces for solid fuel and for oil-firing are generally known. These boilers are primarily intended for solid fuel, such as coke, but can also be provided with an oil burner at the top. A universal boiler of this type is shown for example in the DE-AS No. 1 102 368. In this known boiler, a damper closes an upper passage between the common furnace (combustion chamber) and the flues of the boiler, when the boiler is fired with oil. In this case, the flue gases enter the flues instead via a passage in the lower portion of the boiler. On the other hand, when the boiler is fired with solid fuel, the upper flue is opened as a result of the fact that the damper is moved up and shields the oil burner. This known boiler has the disadvantage common to all universal boilers with a common furnace that the furnace cannot be made in a manner which is optimum for both firing with solid fuel and for oil firing.
Another limitation is that it is not possible to fire simultaneously with solid fuel and with oil, something which may be desirable when the maximum amount of heat is required. This possibility is offered, on the other hand, with the boiler as shown in FIG. 3 in the Swedish Pat. Spec. No. 94 956. In this boiler, the furnace for solid fuel is formed primarily only with a view to burning rubbish and serious disturbing operation must be expected in the oil burner working in the same combustion chamber, particularly as the flue gases from the rubbish combustion sweep directly past in front of the nozzle of the oil burner. Furthermore, the Swedish Pat. Spec. No. 360 458 shows a heating boiler with separate furnaces for firing with gas and/or oil and for solid fuel. The flame from the gas or oil burner is directed towards a perforated wall in the opposite end of the furnace, behind which there may be solid fuel. The hot flue gases from the gas or oil burner do not, however, pass through the perforated wall into the furnace for the solid fuel whether when firing is taking place in this furnace or when only the gas or oil firing is being used. Instead, the flue gases from the furnace (combustion chamber) of the gas/oil burner are always taken off directly upon into a heat-exchange chamber through a pair of flues in the roof of the combustion chamber. The aim of the arrangement is that with a high-speed supply of fuel the flue gases should pass up through both flues but with a low speed supply of fuel they should only pass through the one flue. The possibility of improving the heat economy which this self-regulation can afford is, however, very moderate and the possibilities for a satisfactory heat economy which a suitably formed furnace for solid fuel can give have not been utilized at all. In consequence all possibilities of leading the flue gases from the gas/oil burner into the furnace for the solid fuel have also been completely ignored, something which often happens in boiler constructions with separate furnaces for oil or gas and for solid fuel. Among such known constructions, a heating boiler manufactured by the Swedish Company Exoverken AB under the name "Exo oljepanna typ G och H" may be mentioned for example. On the other hand, this lacks a possibility which the boiler according to the Swedish Pat. Spec. No. 360 458 affords, namely of leading the flue gases from the combustion chamber of the oil burner directly up into a heat-exchange chamber, that is to say up into a system of flues in contact with water, without passing through the furnace for solid fuel, which may be desirable with a low heat requirement. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a two-shaft gas turbine in which a high-pressure turbine for driving a compressor and a low-pressure turbine for power output are configured to have respective different shafts. The two-shaft gas turbine is applied to a gas turbine system having an increased amount of fluid flowing into a combustor compared with a simple cycle, such as, e.g., a humid air system, a steam injection system, a nitrogen injection system, or a low-calorific fuel firing system.
2. Description of the Related Art
For example, JP-A-2003-83081 (FIG. 5) and JP-A-5-18271 describe the technology of a two-shaft gas turbine in which a high-pressure turbine for driving a compressor and a low-pressure turbine for driving a generator or a pump are configured to have respective different shafts.
The two-shaft gas turbine can rotate the compressor and the high-pressure turbine at high speeds even if a driven device (load) such as a pump or a screw is low in rotation speed. Because of this, the two-shaft gas turbine can increase the torque of the low-pressure turbine in a low rotation speed zone. For this reason, the two-shaft gas turbine is mainly used to drive a machine such as a pump or a screw. However, the two-shaft gas turbine can also be used for electric power generation by use of the low-pressure turbine driving a generator. If the low-pressure turbine is used without reduction gears, the two-shaft gas turbine has an advantage that high-efficiency can be achieved by rotating the compressor at high speeds. Even if the reduction gears are used, a reduction ratio can be reduced to advantageously provide reduced cost and improved efficiency.
Incidentally, FIG. 5 of JP-A-2003-83081 describes the technology of a humidity gas turbine system in which moisture is added to gas turbine working fluid (e.g. air) for humidification and the thermal energy of the gas turbine exhaust gas is recovered by a recuperator, thereby improving output power and efficiency.
On the other hand, WO00/25009 discloses the technology of a humidity gas turbine system in which water is added for humidification to the working fluid (e.g., air) of a gas turbine, and the thermal energy of exhaust gas discharged from the gas turbine is recovered by such humidified air and supplied to the gas turbine for improving output power and efficiency. | {
"pile_set_name": "USPTO Backgrounds"
} |
Such chassis parts for connection and force transmission between the vehicle chassis and the wheel, also called control arms, are known, in principle. Furthermore, it has been known, e.g., from DE 38 39 855 A1 that lightweight components comprising a connection between structural parts made of metal and plastic can be manufactured. It is problematic in such composite materials that the plastic portions, especially fiber-reinforced plastic components, may undergo brittle fracture under excessively high loads. This means that such parts may abruptly lose their strength and stability under an excessively high load. The use of such composite materials in chassis control arms therefore represents a certain safety hazard, because, on the one hand, extremely high safety requirements are imposed in such environments, but enormous forces may briefly act on the chassis control arms because of unpredictable driving situations or accident situations. However, such composite materials make possible an extremely low-weight and consequently energy-saving design, so that it is desirable for reasons of the efficient manufacture of vehicles to use such composite materials in chassis control arms as well. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to a caster device and an infant supporting apparatus having the same, and more particularly to a foldable caster device and an infant supporting apparatus having the same.
2. Description of the Related Art
An existing infant rocking bed is typically provided with foldable caster devices. When the caster devices are unfolded, the infant rocking bed could be moved on the ground. When the caster devices are folded, the infant rocking bed is swingable on the ground. Such a foldable caster device is disclosed in U.S. Pat. No. 7,070,188.
The foldable caster device disclosed in U.S. Pat. No. 7,070,188 includes a housing, a rotatable member disposed rotatably on the housing, a caster driven by the rotatable member to rotate, a locking member disposed movably on the housing, and a spring for biasing the locking member. The locking member is biased to engage a selected one of openings in the rotatable member for positioning the caster at an extended position or a retracted position. However, since the locking member projects from a top portion of the housing, the outer appearance of the caster device is affected adversely. That is, the caster device cannot have a neat appearance. Furthermore, such a locking structure renders the manufacture of the caster device more complex to thereby increase the manufacturing costs of the caster device. | {
"pile_set_name": "USPTO Backgrounds"
} |
From time to time, it may be desirable to remove a portion of a vehicle. For example, it may be desirable to remove a trailer, e.g. if the trailer becomes damaged, from a tractor or prime mover moving the trailer. Such a time may occur in a combat situation or another other situation. Once the trailer is removed from the tractor, the tractor may continue without the trailer. It may be advantageous to remove the trailer quickly without stopping movement of the tractor. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a method of resolving racemic amlodipine into its R-(+) and S-(xe2x88x92) enantiomers by precipitation with tartaric acid.
The synthesis of racemic amlodipine (3-ethyl-5-methyl-2-(2-aminoethoxymethyl)-4-(2-chlorophenyl)-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate) and its activity as an inhibitor of calcium channels is described in U.S. Pat. No. 4,572,909 to Campbell et al. Results of in vitro tests to determine calcium antagonist activity of amlodipine enantiomers against calcium-induced constriction of potassium-depolarized rat aorta is described in Arrowsmith et al., J. Med. Chem., (1986) 29, 1696-1702. The authors allege that the (xe2x88x92) stereoisomer is twice as active as the racemic mixture in antagonizing calcium-induced constriction. The S absolute configuration is the (xe2x88x92) optical rotatory form. Goldmann, J. Med. Chem., (1992)35, 3341-44. Desirability of optically pure S-(xe2x88x92)-amlodipine for treatment of hypertension and angina is described in U.S. Pat. No. 6,057,344.
Although R-(+)-amlodipine appears to have little activity as a calcium channel blocker, it is not pharmacologically inert, but rather it is a potent inhibitor of smooth muscle cell migration. WO 95/05822 (now U.S. Pat. No. 6,080,761) to Chahwala et al. Ideally, the preferred mode of using amlodipine would be the administration of the S-(xe2x88x92) enantiomer substantially free of the R-(+) enantiomer. U.S. Pat. No. 6,057,344 to Young. Nonetheless, there is presently no amlodipine product that contains S-(xe2x88x92)-amlodipine substantially free of the R-(+) enantiomer. See, for example, NORVASC(copyright), the active ingredient of which is racemic amlodipine besylate.
Methods of producing enantiomerically pure amlodipine have concentrated on methods of resolving the racemate, i.e., methods of separating the enantiomers of a racemic mixture of amlodipine or an intermediate in the synthesis of amlodipine by stereoselective precipitation. Such methods are known. See EP 331 315 A2 to Arrowsmith (resolution of an amlodipine intermediate by cinchonidine).
Spargo described a method of resolving racemic amlodipine by forming a precipitate in a dimethylsulfoxide (DMSO) solvent by addition of D- or L-tartaric acid. WO 95/25722 (now U.S. Pat. No. 6,046,338). The resultant precipitate consists of amlodipine:tartrate:DMSO in a 2:1:2 ratio, which is termed an amlodipine hemitartrate DMSO monosolvate.
Spargo optionally allowed for the presence of a co-solvent in an amount that is preferably between 0.2% and 6% the volume of DMSO. Suitable co-solvents are taught to include dimethylacetamide, dimethylformamide (DMF), acetonitrile and tetrahydrofuran (THF). Spargo further describes a method of secondarily processing the amlodipine hemitartrate DMSO monosolvate to obtain crystalline amlodipine free base by a process of extraction of the amlodipine hemitartrate DMSO monosolvate in dichloromethane (DCM) with aqueous NaOH to remove the tartrate followed by precipitation with hexane.
However, the use of DMSO renders the method of Spargo unsuitable for large-scale (kilogram) routine production of enantiomeric amlodipine. FDA guidelines point out that DMSO residual concentrations above 0.5% would only be acceptable upon convincing justification. Guidance for Industry IMPURITIES: RESIDUAL SOLVENTS, FDA, September 1999, page 9. Accordingly, there is an art-recognized need for commercially acceptable large-scale methods of resolving amlodipine.
In one aspect, the invention is directed to a method of optically enriching racemic amlodipine, comprising precipitating amlodipine hemitartrate dimethylacetamide monosolvate from a solution comprising amlodipine and either D- or L-tartaric acid, whereby the amlodipine hemitartrate dimethylacetamide monosolvate precipitate is enriched for one enantiomer of amlodipine. In certain embodiments, the ratio of the two enantiomers of amlodipine in the precipitate is at least 8:1, preferably at least 9:1, or even at least 20:1. In certain embodiments, the method includes heating a slurry or solution of amlodipine and tartaric acid, e.g., to a temperature above 35xc2x0 C., preferably above 45xc2x0 C. or even above 55xc2x0 C., such as between 35 and 100xc2x0 C., preferably between 50 and 90xc2x0 C., even more preferably between 60 and 80xc2x0 C. In certain such embodiments, the elevated temperature is maintained for at least 30 min., preferably at least 60 min. or even more than 2 hours. In certain embodiments, the resolution is performed on a scale of more than 1 kg of amlodipine, preferably at least 10 kg or even more than 100 kg of amlodipine.
In another aspect, the invention is directed to a crystalline composition comprising S-(xe2x88x92)-amlodipine D-hemitartrate DMAC monosolvate or, alternatively, R-(+)-amlodipine L-hemitartrate DMAC monosolvate, wherein at least 80% of the amlodipine in the crystalline composition is the predominant enantiomer. Preferably at least 90% of the amlodipine in the crystalline composition is the predominant enantiomer. More preferably at least 97% of the amlodipine in the crystalline composition is the predominant enantiomer. Most preferably at least 99% of the amlodipine in the crystalline composition is the predominant enantiomer.
In yet another embodiment, the invention is directed to solid pharmaceutical dosage forms comprising an optically active amlodipine or a pharmaceutically acceptable salt or hydrate thereof, and a carrier matrix, and to methods for manufacturing such dosage forms. In certain preferred embodiments, at least 80% of the optically active amlodipine in the dosage form is S-(xe2x88x92)-amlodipine, preferably at least 90%, or even 95% or more. | {
"pile_set_name": "USPTO Backgrounds"
} |
Digital media item repositories are common across many businesses and/or personal collections. A digital media item may include one or more of a digital image, a video, an audio file, other non-text-based digital items, digital items that include text, and/or other digital media items. User-contributed collections may be used for some internet businesses. Users may perform searches to find, research, and/or otherwise browse through such collections. Keywords and/or textual metadata may be associated with individual digital media items. The keywords and/or other textual metadata may be indexed for searching purposes. In some contexts, there may be little to no associated keywords or textual metadata associated with individual digital media items. It may be difficult and/or tedious for a user to describe in words a digital media item he or she seeks. | {
"pile_set_name": "USPTO Backgrounds"
} |
In general, a hydraulic control valve is used to control hydraulic fluid that is supplied from hydraulic pumps to actuators that drive working devices, such as a boom and an arm, of a construction machine, such as an excavator. Particularly, in driving working devices, such as the boom and the arm, the driving speed of the working devices can be increased by making the hydraulic fluid supplied from a plurality of hydraulic pumps in a confluent state.
A hydraulic control valve for a construction machine in the related art, as shown in FIGS. 1 and 2, includes a first boom block 1 forming a supply path therein to supply hydraulic fluid of a first hydraulic pump P1 to a boom cylinder 6; a second boom block 2 making close contact with the first boom block 1 to be vertically symmetric to the first boom block 1 and forming a supply path therein to supply hydraulic fluid of a second hydraulic pump P2 to the boom cylinder 6; a first boom spool 3 installed in the supply path 16 of the first hydraulic pump P1 to be shifted to control a start, stop, and direction change of the boom cylinder 6; a second boom spool 4 installed in the supply path 31 of the second hydraulic pump P2 to be shifted to make the hydraulic fluid of the second hydraulic pump P2 join the hydraulic fluid of the first hydraulic pump P1 to increase the driving speed of the boom cylinder 6; and poppets 9 elastically supported by springs 8, respectively, to open and close the supply path 16 of the first hydraulic pump P1 and the supply path 31 of the second hydraulic pump P2.
In the drawing, the reference numerals “12” and “15” denote guides on which springs 13 are seated, which are oppositely fixed to end portions of the first boom spool 3 and the second boom spool 4, and “14” denotes stoppers arranged between the guides 12 and 15 of the first boom spool 3 and the second boom spool 4, respectively, to limit strokes of the first boom spool 3 and the second boom spool 4.
Hereinafter, the operation of the hydraulic control valve as constructed above will be described.
(A) The operation of the hydraulic control valve during a boom-up operation will be described.
As shown in FIG. 1, if pilot signal pressure (pressure that exceeds the predetermined set pressure of a spring 13) for a boom-up operation is supplied to a pilot b port 28 of the cover 10 to lift up the boom, the first boom spool 3 that is slidingly coupled in the first boom block 1 is shifted to the left side.
At this time, the high-pressure hydraulic fluid in the supply path 16 of the first hydraulic pump P1 pushes the poppet 9 that is elastically supported by the spring 8 upward to be supplied to the bridge path 17, and is supplied to the cylinder path 19 through a notch 18 of the first boom spool 3 that is shifted to the left side.
At the same time, as the pilot signal pressure (pressure that exceeds the predetermined set pressure of the spring 13) for the boom-up operation is supplied to a pilot b′ port 29 of the cover 10, the second boom spool 4 that is slidingly coupled in the second boom block 2 is shifted to the left side.
At this time, the high-pressure hydraulic fluid in the supply path 31 of the second hydraulic pump P2 pushes the poppet p that is elastically supported by the spring 8 downward to be supplied to the bridge path 32, and is supplied to the cylinder path 34 through a notch 33 of the second boom spool 4 that is shifted to the left side.
The hydraulic fluid supplied to the cylinder path 34 joins the hydraulic fluid in the cylinder path 19 on the side of the first boom block 1, and then is supplied to a large chamber of the boom cylinder 6 through an actuator B port 20 and a boom large chamber path 21. Through this, the boom is lifted up.
At this time, leakage of the high-pressure hydraulic fluid is prevented by an O-ring 36 provided on a mutual close-contact surface of the first and second boom blocks 1 and 2.
On the other hand, the hydraulic fluid that returns from a small chamber of the boom cylinder 6 passes through the boom small chamber path 22, the actuator A port 23, and the cylinder path 24 in order, and returns to the tank path 26 through the notch 25 of the first boom spool 3 that is shifted to the left side. Accordingly, the boom is lifted up.
At this time, since the amount of hydraulic fluid that returns from the small chamber of the boom cylinder 6 is equal to or less than a half of the hydraulic fluid of the large chamber, the hydraulic fluid returns to the hydraulic tank only through the first boom spool 3. At this time, in the second boom spool 4 that is shifted to the left side, the notch that communicates with the tank path 37 is not formed, and the hydraulic fluid does not return to the hydraulic tank through the second boom spool 4.
At this time, if the pressure that exceeds the predetermined set pressure is applied to the boom cylinder 6, relief valves 5, which are installed on the actuator A port 23 and the actuator B port 20, make the hydraulic fluid having the excessive pressure return to the hydraulic tank to maintain the predetermined set pressure, and thus the boom cylinder 6 can be protected.
(B) The operation of the hydraulic control valve during a boom-down operation will be described.
As shown in FIG. 1, if pilot signal pressure for a boom-down operation is supplied to a pilot a port 27 and a′ port 30, the first boom spool 3 that is slidingly coupled in the first boom block 1 and the second boom spool 4 that is slidingly coupled in the second boom block 2 are shifted to the right side.
At this time, the high-pressure hydraulic fluid in the supply path 16 of the first hydraulic pump P1 pushes the poppet 9 that is elastically supported by the spring 8 upward to be supplied to the bridge path 17, and is supplied to the cylinder path 24 through the notch 38 of the first boom spool 3 that is shifted to the right side.
Further, the high-pressure hydraulic fluid in the supply path 31 of the second hydraulic pump P2 pushes the poppet 9 that is elastically supported by the spring 8 downward to be supplied to the bridge path 32. By contrast, in the second boom spool 4 that is shifted to the right side, the notch that communicates with the bridge path 32 is not formed, and thus the high-pressure hydraulic fluid in the supply path 31 of the second hydraulic pump P2 is not supplied to the cylinder path 39 through the second boom spool 4.
Accordingly, only the hydraulic fluid on the side of the first hydraulic pump P1 is supplied to the small chamber of the boom cylinder 6 through the actuator A port 23 and the boom small chamber path 22.
On the other hand, the hydraulic fluid, which returns from the large chamber of the boom cylinder 6 passes through the boom large chamber path 21, the actuator B port 20, and the cylinder path 19 in order, and then dispersedly returns to the tank path 42 and the tank path 43 through the notch 40 formed on the first boom spool 3 that is shifted to the right side and the notch 41 formed on the second boom spool 4. Accordingly, the boom can lower.
FIG. 2 is a hydraulic circuit diagram of a hydraulic control valve for a construction machine in the related art.
(A) The boom-up operation will be described with reference to the hydraulic circuit.
If the pilot signal pressure for the boom-up operation is supplied to a b port of the first boom block 1, the first boom spool 3 that is coupled to the first boom block 1 is shifted to the right side. At this time, the high-pressure hydraulic fluid in the supply path 16 of the first hydraulic pump P1 pushes a check valve 55, and is supplied to paths 56 and 57 through the internal path of the first boom spool 3 that is shifted to the right side.
At the same time, if the pilot signal pressure for the boom-up operation is supplied to a b′ port of the second boom block 2, the second boom spool 4 of the second boom block 2 is shifted to the right side. At this time, the high-pressure hydraulic fluid in the supply path 31 of the second hydraulic pump P2 pushes a check valve 62, and is supplied to a path 63 through the internal path of the second boom spool 4 that is shifted to the right side. Through this, the hydraulic fluid that is supplied to the path 63 joins the hydraulic fluid on the side of the first hydraulic pump P1 in the path 57 and is supplied to the large chamber of the boom cylinder 6.
At this time, the hydraulic fluid that returns from the small chamber of the boom cylinder passes through the path 59, and then is supplied to the tank path 60 through the internal path of the first boom spool 3 that is shifted to the right side.
(B) The boom-down operation will be described with reference to the hydraulic circuit.
If the pilot signal pressure for the boom-down operation is supplied to a port of the first boom block 1 and an a′ port of the second boom block 2 to let the boom can lower, the first boom spool 3 of the first boom block 1 and the second boom spool 4 of the second boom block 2 are shifted to the left side, respectively. At this time, the high-pressure hydraulic fluid in the supply path 16 of the first hydraulic pump P1 pushes the check valve 55, and is supplied to a path 59 through the internal path of the first boom spool 3 that is shifted to the left side. Through this, the hydraulic fluid is supplied to the small chamber of the boom cylinder 6.
At this time, the hydraulic fluid that returns from the larger chamber of the boom cylinder 6 is supplied to the paths 57 and 56, and is supplied to the tank path 60 through the internal path of the first boom spool 3 that is shifted to the left side.
At the same time, the hydraulic fluid that returns from the large chamber of the boom cylinder 6 is supplied to the path 63 that is branched to the path 57, and is supplied to the tank path 64 through the internal path of the second boom spool 4 that is shifted to the left side. Through this, the boom can lower.
As described above, the hydraulic control valve in the related art includes the first boom block 1 and the second boom block 2 for the boom-up or boom-down operation, the first boom spool 3 and the second boom spool 4 that are slidingly coupled to the first boom block and the second boom block 2, and the poppets 9 that are elastically supported by the springs 8 to open and close the supply path 16 of the first hydraulic pump P1 and the supply path 31 of the second hydraulic pump P2. Since such construction is applied to a first arm spool and a second arm spool in the same manner, the hydraulic control value becomes large-sized.
Further, in the case of mounting the hydraulic control valve onto the construction machine, the large-sized hydraulic control valve causes inconvenience during piping and layout of the hydraulic control valve which increases the manufacturing cost. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to an X-ray diagnostic apparatus which displays a road map representing a blood vessel structure.
2. Description of the Related Art
In intervention or angiographic examination, a catheter is inserted into a blood vessel from, for example, the joint of a leg and is brought to a target region through the blood vessel. This catheter or a guide wire inserted in the catheter is moved forward to a target position under fluoroscopic observation of an X-ray image. However, the blood vessel cannot be seen in an X-ray image unless enhanced by a contrast medium. Keeping injecting the contrast medium to visualize the blood vessel may result in renal failure. For this reason, there is available a function of holding an X-ray image of a blood vessel obtained by radiography after a contrast medium is injected once as a two-dimensional road map, and displaying the image upon superimposing it on an X-ray fluoroscopic image obtained in real time. This function allows the operator to discriminate the position of a blood vessel to a certain extent without injecting any contrast medium, and hence is often used especially when a blood vessel structure is complicated and it is difficult to push a catheter or a guide wire into the blood vessel.
When, however, a road map is converted into a three-dimensional image, a portion other than the catheter or guide wire, e.g., a bone, is imaged. This makes it very difficult to see the image of the catheter or guide wire. | {
"pile_set_name": "USPTO Backgrounds"
} |
More specifically, the invention concerns a method using at least one crown compound, either to recover the final traces of plutonium in aqueous solutions polluted by salts of this metal, for example concentrated solutions of fission products derived from the reprocessing of irradiated fuels and the effluents from reprocessing installations, or to separate the plutonium from americium from concentrated solutions of plutonium.
For several years, the most widely used technique to reprocess irradiated nuclear fuels consists of dissolving the fuel in a nitric solution and of then placing the nitric solution obtained in contact with an organic solvent so as to extract from the latter the uranium and the plutonium and to separate them from most of the fission products which remain in the aqueous solution; this aqueous solution corresponds to a concentrated fission product solution, but it generally contains traces of plutonium which need to be recovered. Similarly, at the end of processing, aqueous effluents are also recovered containing traces of plutonium which need to be recovered.
Currently known methods to carry out this type of processing result in obtaining satisfactory results, but it is still advantageous to further improve the plutonium decontamination percentage of all these solutions.
Another problem concerning the decontamination and purification of plutonium exists in the case of concentrated plutonium solutions which, when ageing, are found to be contaminated by plutonium offspring, such as americium, which need to be separated. | {
"pile_set_name": "USPTO Backgrounds"
} |
One type of liquid crystal light valve is a projection-type image display apparatus. The light valve comprises an evacuated ceramic envelope that incorporates a pair of opposing transparent windows as part of the envelope wall. One window forms part of a liquid crystal cell. The remainder of the cell is assembled adjacent to the inner surface of that window. Polarized light is typically directed through the envelope windows. The light exiting the liquid crystal cell passes through a polarizing filter or analyzer. Any light passing through the analyzer is transmitted via a projection lens system onto a suitable viewing surface.
The liquid crystal cell includes liquid crystal material captured between two substrates. One substrate is formed of glass and is incorporated into the wall of the envelope to serve as a window as mentioned above. The opposing substrate comprises a thin dielectric material. The cell is preferably of the twisted nematic type, which is constructed so that in the absence of an applied electric field (i.e., with the cell in the "OFF" state) the cell rotates by 90.degree. the polarization direction of the projected light. With the cell in the "OFF" state, no light passes through the analyzer and the viewing surface remains dark. When an electric field is applied to the cell (i.e., when the cell is switched to the "ON" state) the projected light passes through the cell with the polarization direction unchanged. As a result, the light passes through the polarizing analyzer to the viewing surface.
An electron beam-addressed liquid crystal light valve employs an electron beam for modulating the polarization direction of light passing through the liquid crystal cell. Specifically, an electron gun is mounted within the light valve envelope and provides a beam of electrons that strike the side of the liquid crystal cell carrying the thin dielectric substrate, which is called the target substrate. The electron beam direction is deflected by suitable circuitry to raster scan the target substrate. A collector electrode is mounted within the liquid crystal light valve near the target substrate. To produce or "write" an image, the electron beam and collector electrode positioned above and over the target substrate cooperate to develop an electrostatic potential at certain points on the surface of the target substrate that correspond to the desired image. As a result, those points on the liquid crystal cell are switched to the "ON" state, thereby permitting associated portions of the projected light of unchanged polarization direction to pass through the valve and form the image on the viewing surface.
As noted, the target substrate for an electron beam-addressed liquid crystal light valve preferably comprises thin dielectric material. The target substrate must be thin to minimize spreading of the electric field lines produced by the charge deposited on the surface. Spreading of the field lines reduces the resolution of the projected image. A film of five to ten microns in thickness forms a suitable target substrate.
Copending U.S. patent application of Buzak et al., Ser. No. 046,822, entitled Liquid Crystal Light Valve with Electrically Switchable Secondary Electron Collector Electrode, filed concurrently herewith, describes a particular configuration and optimal operation mode for an electron beam-addressed liquid crystal light valve. More particularly, that application describes write and erase modes wherein the collector electrode is configured and arranged to create strong collecting fields to control the redistribution of secondary electrons generated by the electron gun. When in the write mode, the collector electrode is maintained at positive voltage relative to the target substrate as the electron beam bombards the target substrate with electrons of sufficient energy to result in secondary electron emissions from the target substrate surface. The secondary electrons are collected on the positively charged collector electrode. The rate of secondary electron emission is greater than the rate the incident electrons are delivered by the electron gun. Consequently, the beam-addressed area of the target substrate surface is driven positive. This change in potential switches the corresponding region of the liquid crystal cell to the "ON" state
To erase the image (i.e., to switch the previously written region of the liquid crystal cell to the "OFF" state), the collector electrode is switched to a negative potential relative to the written region of the target substrate. An electron beam, either emanating from the same gun as used for writing or from a separate gun, is scanned over the target substrate. The resulting secondary electrons, repelled by the negatively charged collector electrode, are directed to the previously written (positively charged) regions. Accordingly, the positive potential difference at the previously written areas of the target substrate is removed and the corresponding region of the liquid crystal cell is switched to the "OFF" state.
The above-noted copending U.S. patent application presents an operating mode for an electron beam-addressed liquid crystal light valve wherein both a writing electron gun and an erasing electron gun are operated to produce electron beams with energy suitable for generating secondary electrons at a rate greater than the rate the incident electrons are delivered by the beams (the latter rate being the beam current). The ratio of secondary electron emissions to incident electrons is known as the secondary electron emission ratio. Accordingly, for the operating modes just described, the writing and erasing guns are controlled so that the secondary electron emission ratio is always greater than one.
For any given beam energy, the rate of secondary electron emissions from the substrate varies depending upon the material used as the target substrate. Further, it is desirable to bombard the substrate with relatively low incident beam current to minimize the beam spot size and produce a correspondingly higher resolution image. | {
"pile_set_name": "USPTO Backgrounds"
} |
Natural resources such as gas, oil, and water residing in a subterranean formation or zone are usually recovered by drilling a wellbore into the subterranean formation while circulating a drilling fluid in the wellbore. After terminating the circulation of the drilling fluid, a string of pipe (e.g., casing) is run in the wellbore. The drilling fluid is then usually circulated downward through the interior of the pipe and upward through the annulus, which is located between the exterior of the pipe and the walls of the wellbore. Next, primary cementing is typically performed whereby a cement slurry is placed in the annulus and permitted to set into a hard mass (i.e., sheath) to thereby attach the string of pipe to the walls of the wellbore and seal the annulus.
Subsequent secondary cementing operations may also be performed. One example of a secondary cementing operation is squeeze cementing, whereby a cement slurry is employed to plug and seal off undesirable flow passages in the cement sheath and/or the casing. Non-cementous sealants are also utilized in preparing a wellbore. For example, polymer, resin, or latex-based sealants may be desirable for placement behind casing.
To enhance the life of the well and minimize costs, sealant slurries are chosen based on calculated stresses and characteristics of the formation to be serviced. Suitable sealants are selected based on the conditions that are expected to be encountered during the sealant service life. Once a sealant is chosen, it is desirable to monitor and/or evaluate the health of the sealant so that timely maintenance can be performed and the service life maximized. The integrity of sealant can be adversely affected by conditions in the well. For example, cracks in cement may allow water influx while acid conditions may degrade cement. The initial strength and the service life of cement can be significantly affected by its moisture content from the time that it is placed. Moisture and temperature are the primary drivers for the hydration of many types of cement and are critical factors in the most prevalent deteriorative processes, including damage due to freezing and thawing, alkali-aggregate reaction, etc.
Accordingly, an ongoing need exists for methods of monitoring wellbore sealant conditions from placement through the service lifetime of the sealant. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a spindle motor and a disk drive apparatus.
2. Description of the Related Art
A disk drive apparatus, such as, for example, a hard disk drive, includes a spindle motor arranged to rotate a recording disk. A base of a spindle motor described in JP-A 2012-151940 includes a base draw-out hole. A lead wire from a coil passes through the base draw-out hole. The lead wire is soldered to a wiring member arranged on a lower surface of the base.
If the lead wire obliquely passes through the base draw-out hole, the lead wire is brought into contact with a hole edge of the base draw-out hole as illustrated in FIG. 3 of JP-A 2012-151940. If the lead wire is brought into contact with the hole edge, an insulating coating of the lead wire may be damaged. Damage to the coating of the lead wire may lead to defective insulation due to a portion of the coating being stripped off. Moreover, the lead wire, with a portion of the coating being stripped off, and the base may become electrically connected with each other, and a short circuit may occur. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to wheeled load handling devices and more particularly to the handling of firewood log sections as the loads.
Wheeled hand trucks for pick-up, transport and delivery of various types of loads are already well known. Such load handlers generally include a frame having a front load pick-up end, a pair of wheels supporting the frame adjacent to the front end and grip handles at the rear end for manually pushing or pulling and angularly tilting the frame about the wheel axles. Some of such load handlers also mount pivoted hooks to engage the rim portions of certain types of loads, such as barrels, to hold the loads on the frame. However, the design and arrangement of parts associated with such known load handlers are unsuitable for the handling of firewood logs.
Firewood logs have heretofore required manual handling despite the availability of aforementioned wheeled load handling devices, because the logs must be picked off the ground and deposited onto some elevated surface such as a log splitter. The variation in size of such logs, the lack of any grippable rim and the rough cylindrical shape of the logs makes handling difficult and inefficient with any available load handler in a relatively small scale operation. It is therefore an important object of the present invention to provide a load handler specifically designed to efficiently assist in the handling of firewood logs.
A further object of the present invention is to provide a special load handler for firewood logs that is economically feasible to manufacture and cost effective for marketing to small scale operation consumers as well as large scale users. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a process for the preparation of an ester using a polyaniline salt as the catalyst. The present invention more particularly relates to a process for producing aliphatic esters by the direct esterification of aliphatic mono carboxylic acids with aliphatic monohydric alcohols over polyaniline salts as catalysts.
Esters are useful in a wide variety of industrial applications, such as for use in making coatings, adhesives, resins, fragrances, perfumes, plasticizers etc. Esterification is a well known equilibrium limited reaction involving reaction of a mono-, di- or polycarboxylic acid (or, in suitable cases, an acid anhydride) with an alcohol or phenol component. Such an alcohol or phenol component can be mono, di- or polyhydric.
Several synthetic routes exist to make esters, but most of them are not suitable to meet the stringent specifications which are being applied in the chemical industry. The most acceptable method of making an ester is to react an acid with an alcohol in the presence of catalyst.
Esterification is one of the most fundamental and important reactions in organic synthesis. Conventionally, the processes of making esters from acids and alcohols can be classified into the following three main categories: (R. C. Larock, Comprehensive Organic Transformations, VCH, New York, 1989, page 966, references therein, Encyclopedia of Chemical Technology, Vol 9, 4th Edition, Wiley Interscience Publications, Page 755, references therein: Ullmann""s Encyclopedia of Industrial Chemistry, Vol. 10, Vth Edition, 1987, Page 281, references therein; Vogel""s, Text book of Practical Organic Chemistry, Longman Group Ltd., England, Vth Edition, 1996).
(a) Liquid-phase esterification reaction utilizing a liquid catalyst: This type of processes utilize liquid phase acid, such as sulfuric acid, phosphoric acid, sulfonic acid, or p-toluene sulfonic acid, as catalysts.
(b) Liquid phase esterification reaction utilizing a solid catalyst: This type of processes typically utilize inorganic salts, cationic ionic exchange resin and solid acid catalyst etc.
(c) Gas phase esterification reaction: This type of processes utilize a variety of catalysts such as heteropolyacids, liquid phase acids carried by a solid carrier, and zeolite in a gas phase reaction.
One of the problems associated with the liquid-catalyst liquid-phase esterification reaction is that the acidic liquid catalysts of sulfuric acid or p-toluene sulfonic acid cause corrosion in the reactor. These liquid acid catalysts are also discharged along with the reaction products, thus causing serious waste disposal and pollution problems. The drawbacks of using mineral acid as catalyst are: (i) Catalyst can not be reused, (ii) Disposal of acid is not environmentally safe and it is not economical, (iii) Low selectivity is frequently observed, (iv) Corrosion of the reaction vessel and reactors, (v) Not easy to handle and (iv) High inventory of the catalyst.
The solid-catalyst, liquid-phase esterification reaction, which typically utilizes a cationic ionic exchange resin as catalyst, ameliorates the corrosion and waste disposal problems experienced with the liquid-catalyst liquid-phase processes, and results in simplified separation procedure required between the reaction product and catalysts. However, cationic ion-exchange resins typically exhibit relatively poor heat-resistance, and they often lose substantial activity after being subject to heat. Once the catalytic activity of the cationic ion-exchange resins is reduced, it is difficult to be regenerated.
In the gas phase esterification reaction, the reaction conditions are maintained so that all the reactants and products are in the gas phase. Typically, inorganic materials are utilized as catalysts which typically exhibit excellent heat resistance and can be easily separated from the reaction products. However, the gas phase reaction necessitates a relatively large reaction vessel, resulting in large capital investment cost. Furthermore, if the gas phase esterification reaction is utilized to produce unsaturated carboxylic esters, the high reaction temperature often causes undesired by-products of polymers or oligomers to be produced. In certain instances, the high reaction temperature has caused the alcohol molecules to be dehydrated to become ethers. These side-reactions will tend to cause the reaction catalysts to lose their activity and result in operational difficulties.
The main object of the present is to provide a process for preparation of esters using polyaniline-salts as catalysts which obviates the drawbacks as detailed above.
It is another object of the invention to provide a process for the preparation of an ester which is environmentally safe.
It is a further object of the invention to provide a process for the preparation of an ester that allows catalyst recycling.
It is still another object of the invention to provide a process that is economical and efficient.
Another object of the present invention is to produce aliphatic esters by the direct esterification of aliphatic mono carboxylic acids with aliphatic monohydric alcohols over polyaniline salts as catalysts.
Accordingly, the present invention relates to a process for preparation of an ester said process comprising direct esterification of an aliphatic mono carboxylic acid with an aliphatic mono hydric alcohol in presence of a polyaniline salt catalyst at a temperature in the range of 40 to 80xc2x0 C. for a time period in the range of 8 to 24 hrs. and separating the ester so obtained from the reaction mixture.
In one embodiment of the present invention, the aliphatic mono carboxylic acid used is selected from aliphatic mono carboxylic acids having C2-C20 carbon atoms.
In an another embodiment of the present invention, the aliphatic mono hydric alcohol used is selected from mono hydric alcohols having C1-C20 carbon atoms.
In a further embodiment of the invention, the aliphatic monohydric alcohol is selected from iso propyl alcohol and tertiary butyl alcohol.
In yet another embodiment of the present invention, the polyaniline salt catalyst used is selected from polyaniline-sulfate, polyaniline-hydrochloride, polyaniline-nitrate, polyaniline-p-toluene sulfonate and polyaniline-phosphoric acid salt.
In another embodiment of the invention the reaction is carried out in the temperature range of 70 to 80xc2x0 C.
In yet another embodiment of the invention, the reaction is carried out for a period of 20 to 24 hrs.
In still another embodiment of the present invention, the catalyst amount used is in the range of 100 to 400 mg.
In yet another embodiment of the present invention, the amount of alcohol used is in the range of 1 ml to 5 ml.
These embodiments will be apparent from the ensuing detailed description of the present invention.
The process of esterification may be carried out by reacting aliphatic mono carboxylic acid with aliphatic mono hydric alcohol in presence of catalyst, removing the catalyst by conventional methods. The ester can be isolated such as filtration followed by isolation of esters by conventional column chromatography using adsorbent such as silica gel and solvent such as chloroform, ethylacetate, hexane and mixture there off. | {
"pile_set_name": "USPTO Backgrounds"
} |
This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Due to increased expenses associated with providing energy and a desire to conserve natural resources, legislation and standards are being put in place to encourage improved energy efficiency. One example is the Energy Star Program, which provides standards for power consumption by electronic devices such as televisions and set top boxes. The Energy Star standard specifies requirements for operating modes called “Standby Power” and “Run Mode.” Energy conservation is achieved by reducing or completely removing power from various device subsystems in Standby Power mode relative to Run Mode. Moreover, device systems that are not needed unless the device is being used by a user (“Run Mode”) may be shut down in Standby Mode to conserve power.
In addition to saving power when devices are in Standby Mode, it is also desirable to reduce device power consumption in when operating in Run Mode. However, a number of obstacles make shutting down the operation of device subsystems during Run Mode undesirable. For example, if a user switches from an NTSC analog channel to an external video input like a DVD player, the TV tuner could potentially be turned off to save power because it is not necessary for the TV tuner video input to be processed and displayed on the screen. The drawback to turning off the tuner is that tuners require a relatively long period of time to become operational or “warm up” when power is reapplied. This means that the previously tuned channel will not be immediately available if the user switches back to the NTSC tuner from the DVD player. During the intervening time, the user is undesirably subjected to viewing a “blanked” display. This problem is particularly pronounced with the viewing of digital channels because the process of acquiring a valid “I Frame” on a digital channel may take several seconds, resulting in a much longer “blanked” time that could be annoying to users. An improved system and method for providing reduced power consumption for an electronic device that is being used for normal operation is desirable. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to an authentication device, an authentication method, a program, and a signature generation device
2. Description of the Related Art
With a rapid development of information processing technology and communication technology, digitisation of documents, official and private, is rapidly advancing. Accordingly, many individuals and companies are greatly interested in security management of electronic documents. With the increase in the interest, security against tampering, such as eavesdropping and forgery of electronic documents, has come to be hotly debated in many fields. The security against eavesdropping on an electronic document is ensured by encrypting the electronic document, for example. Also, the security against forgery of an electronic document is ensured by using a digital signature, for example. However, encryption and the digital signature have to be sufficiently tamper-resistant.
The digital signature is used for specifying the author of an electronic document. Accordingly, the digital signature should be able to be generated only by the author of the electronic document, if a malicious third party is able to generate the same digital signature, such third party can impersonate the author of the electronic document. That is, an electronic document is forged by the malicious third party. Various opinions have been expressed regarding the security of the digital signature to prevent such forgery. As digital signature schemes that are currently widely used, schemes that use a RSA signature scheme and a DSA signature scheme are known, for example.
The RSA signature scheme takes “difficulty of prime factorisation of a large composite number (hereinafter, prime factorisation problem)” as a basis for security. Also, the DSA signature scheme takes “difficulty of solving discrete logarithm problem” as a basis for security. These bases are based on that algorithms that efficiently solve the prime factorisation problem and the discrete logarithm problem by using a classical computer do not exist. That is, the difficulties mentioned above suggest the computational difficulty of a classical computer. However, it is said that solutions to the prime factorisation problem and the discrete logarithm problem can be efficiently calculated when a quantum computer is used.
Similarly to the RSA signature scheme and the DSA signature scheme, many of the digital signature schemes and public key authentication schemes that are currently used also take difficulty of the prime factorisation problem or the discrete logarithm problem as a basis for security. Thus, if the quantum computer is put to practical use, security of such digital signature schemes and public key authentication schemes will not be ensured. Accordingly, new digital signature schemes and public key authentication schemes are desired that take as a basis for security a problem different from problems such as the prime factorisation problem and the discrete logarithm problem that can be easily solved by the quantum computer. As a problem which is not easily solved by the quantum computer, there is a difficulty of solving a multivariate polynomial (hereinafter, multivariate polynomial problem), for example.
For example, as digital signature schemes that take the multivariate polynomial problem as a basis for security, those based on Matsumoto-Imai (MI) cryptography, Hidden Field Equation (HFE) cryptography, Oil-Vinegar (OV) signature scheme, and Tamed Transformation Method (TTM) cryptography are known. For example, a digital signature scheme based on the HFE is disclosed in Jacques Patarin, Asymmetric Cryptography with a Hidden Monomial, CRYPTO 1996, pp. 45-60 and Patarin, J., Courtois, N., and Goubin, L., QUARTZ, 128-Bit Long Digital Signatures, In Naecache, D., Ed. Topics in Cryptology—CT-RSA 2001 (San Francisco, Calif., USA, April 2001), vol. 2020 of Lecture Notes in Computer Science, Springer-Verlag., pp. 282-297. | {
"pile_set_name": "USPTO Backgrounds"
} |
The up to now available processes are characterized by the fact that no solid acid catalyst could be used, unless the catalyst is operated under unattractively severe conditions or unless the catalyst is combined with corrosive Lewis acid cocatalyst or unless the catalyst is used in a non-aqueous reaction system.
In particular from International Application WO 96/20154 a process is known for production of trialkylacetic acids from branched olefins and carbon monoxide in a non-aqueous reaction system using a solid resin catalyst comprising a cationic resin, having sufficient acid groups to provide requisite protons for conversion of branched olefin and carbon monoxide to trialkylacetic acids.
In particular the cationic resin was specified to have an acidity of at least equivalent to that of a 65 wt % sulphuric acid.
It will be appreciated by an average person skilled in the art that the process can only be performed in two steps, in the first step of which stoichiometric amounts of branched olefin and water will not lead to the desired products in an acceptable yield. Moreover, the process cannot produce more than 1 mole of converted olefin per mole active proton on the solid catalyst in one cycle of two steps.
In WO 92/18592 a process is suggested for manufacture of trialkylacetic acids and particularly of pivalic acid, from branched olefins and particularly isobutene, and carbon monoxide, using a solid acid catalyst together with minor amounts of a Lewis acid, such as boron trifluoride.
EP-A-0249976 suggests a process for the manufacture of branched carboxylic acids, by catalytic conversion of olefins with carbon monoxide and water in the presence of zeoliths as catalysts at temperatures of from 200 to 500.degree. C. and at pressures of 200 to 700 bar.
More in particular zeoliths of the pentasil type are used as catalysts. According to the exemplified embodiments only high temperatures (300.degree. C.) and pressures (300-500 bar) are used.
It will be appreciated that the disclosed reaction conditions will give rise to higher operation costs due to required measures as to safety and environment.
Therefore there is still a strong need for further improvement of the manufacturing process of branched carboxylic acids, starting from branched olefins and carbon monoxide.
An object of the present invention is to provide an improved manufacturing process for branched carboxylic acids, which process uses relatively mild conditions on the one hand and which shows high conversion and high selectivity to branched acids on the other hand. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The invention relates to a method of initializing, provisioning, and managing a cable modem and a customer premise equipment device. The invention further relates to a subscriber gateway device for connecting to a provider network.
2. Background Art
The modern hybrid fiber coax (HFC) network in its typical implementation includes fiber from the head end to the local network fiber node, and includes coax cable for the final signal distribution through a neighborhood. Modern two-way HFC infrastructures are capable of sending gigabytes of data per second to small pockets of homes in a narrowcast way.
Product and service offerings over broadband networks, including cable networks, have expanded in recent years. The cable networks are now used for additional products and services, for example, many cable networks now offer high speed data service in addition to video programming. In the modern HFC network, head end infrastructure may include a cable modem termination system (CMTS) for providing data over cable services in addition to video quadrature amplitude modulation (QAM) infrastructure for providing video content. The video QAMs may connect to various content sources, while the CMTS connects subscribers to the provider network. The provider network may include a variety of infrastructure for providing various services. For example, the provider network may include Domain Name System (DNS) servers, dynamic host configuration protocol (DHCP) servers, voice over Internet protocol (VoIP) gateways and soft switches for connecting to phone networks, among other systems for providing services to subscribers. Further, advances in network technology allow some functionality to be provided from locations upstream or downstream of the traditional head end.
At a subscriber location, a cable modem and a customer premise equipment device such as a set-top box communicate with the head end over the HFC network. In certain applications, it is desirable for both the cable modem and the set-top box to each have a network address. Traditionally, the cable modem utilizes known initializing and provisioning techniques to obtain a network address and establish a connection to the provider network. For example, the data-over-cable service interface specifications (DOCSIS) specify various protocols for managing the connection of a cable modem to a CMTS. In a traditional application where the provider network is an Internet protocol (IP) network utilizing IPv4 addressing, the cable modem can obtain an IP address in a known manner, and customer premise equipment connected to the HFC network through the cable modem may obtain an IP address, for example, by utilizing DHCP.
Although the traditional IPv4 networks have been used for many applications that have been successful, this addressing approach has certain limitations, for example, the number of addresses available. There is a desire to utilize a more advanced addressing technique such as, for example, IPv6.
DOCSIS 3.0 does provide a way to initialize, provision, and manage a cable modem connected to an IPv4 or an IPv6 provider network. During initialization, the CMTS initializes the cable modem such that the cable modem obtains an appropriate IP address. However, in this approach, a customer premise equipment device such as a set-top box connected to the cable modem that needs to dynamically obtain an address is not made aware of the address type of the provider network. In order for the set-top box to obtain a network address, the set-top box could sequentially make requests for different types of addresses until eventually an address of the correct type is requested and obtained. For example, a set-top box could request an IPv4 address, and if there is no response, request an IPv6 address. Unfortunately, in a large network, these transactions create significant excessive and unwanted network traffic.
For the foregoing reasons, there is a need for a method of initializing, provisioning, and managing a cable modem and a customer premise equipment device in which the customer premise equipment device is informed as to the proper network address type of the network so as to avoid unnecessary transactions which become very significant in a large network implementation. | {
"pile_set_name": "USPTO Backgrounds"
} |
The culturing of living cells in vitro is performed for a variety of purposes, including the preparation of viral vaccines, the recovery of valuable by-products of cell metabolism and the production of tissue-like derivatives for creating artificial organs.
Several problems are associated with growing living cells in vitro to produce dense masses of cells. First, individual components of the nutrient medium must diffuse through the cell layers to reach all cells. This becomes increasingly difficult as the thickness of the cell layer increases.
Second, the maintenance of a suitable environment for cell growth is difficult because the fluid immediately adjacent a growing cell is continuously changing as cellular metabolism proceeds and is returned to its original status only in stepwise fashion when the nutrient medium is changed or agitated en masse.
Third, a lattice or suitable material upon which to grow some types of cells is required.
Various types of apparatus and methods have been developed in response to these needs. One method involves attaching and growing cells on the interior surface of plastic or glass roller tubes and bottles as disclosed in U.S. Pat. No. 3,450,598. Another method involves attaching the cells to a flat surface of stationary containers such as petri dishes or rectangularly shaped culture plates. The flat surfaces can be stacked one on top of each other in a spaced-apart array as disclosed in U.S. Pat. No. 3,843,454.
The use of hollow fibers or synthetic capillaries has more recently been disclosed as a support matrix for the propagation of cells. For example, U.S. Pat. Nos. 3,821,087; 3,883,393; 4,184,922; 4,200,689; 4,206,015 and 4,220,725, all to Knazek et al, variously disclose apparatus and methods for the in vitro growth of cells on semi-permeable, tubular membranes or capillaries wherein cells are initially allowed to settle onto the outer surfaces of the capillary walls in a nutrient medium. Nutrients diffuse from the perfusing medium through the capillary walls and are utilized by the cells. Cell products diffuse from the cells, through the capillary walls and into the perfusate, from which cell products may be recovered.
U.S. Pat. Nos. 4,184,922 and 4,200,689 disclose cell culturing devices comprising a single bundle of fibers wherein some of the fibers are connected to one perfusion circuit and the remaining fibers are connected to a second perfusion circuit. The difference in pressure between the two circuits produces convective currents of perfusate within the extracapillary space and thereby improves nutrient distribution to the growing cells.
In U.S. Pat. No. 4,220,725, a bundle of capillaries, upon which cells are allowed to grow, is wrapped in a porous envelope or sheet material which creates an extra-envelope space into which the cells can migrate for periodic removal without disturbing the main cell culture. The creation of the extra-envelope space increases the surface area for nutrient end waste product diffusion to and from the cells located on the outer surface of the capillaries.
In U.S. Pat. No. 3,997,396, cells are attached to and grown on one side or surface of a single hollow fiber membrane wherein the cells are propagated and maintained by passing oxygen through the membrane from the side opposite that to which the cells are attached and into contact with the cells while simultaneously incubating the cells in a nutrient medium. By continuously passing oxygen through the membrane from the side opposite that on which the cells are attached, a continuous and uniform supply of oxygen reaches and nourishes the cells thereby facilitating aerobic propagation of the cells in the desired tissue densities.
In U.S. Pat. Nos. 4,087,327 and 4,201,845 to Feder et al, an in vitro cell culture reaction system is disclosed which utilizes elongate hollow or solid fibers arranged in a shallow layer configuration as a matrix for cell attachment on the outer surface of the fibers. Nutrient media flow is directed substantially uniformly through the fiber layer and substantially transverse to the plane of the elongate axes of the fibers. The cells are aerated by passing oxygen through the interior of the fibers which then permeates the fiber walls. The use of a shallow bed of fibers in a relatively short path of media flow results in a substantial reduction of the nutrient and metabolic product gradients that is normally produced by the fibrous bundle as well as a more extensive utilization of the fiber surface for cell attachment.
U.S. Pat. No. 4,391,912 discloses a device for cultivating floating animal cells comprising a gas permeable shell and a plurality of hollow fibers enclosed within the shell, wherein the hollow fibers are open at either end outside of the shell and have a pore diameter of from about 102 angstroms to 5.times.10.sup.4 angstroms. Nutrient medium passes through the interior of the hollow fibers and oxygen passes through the shell and the animal cells are cultivated in the space between the shell and the hollow fibers. These pore diameters of the hollow fibers are disclosed as optimizing efficient exchange of nutrients and metabolic products produced by the cells resulting in high density cell growth.
Notwithstanding the usefulness of the hollow fiber cell culture devices, it has been found that the nutrient media flow through the hollow capillaries prevents complete penetration of the capillary bundle by the cells and sets up an undesirable gradient of medium flow. As a result, there is an incomplete utilization of the available capillary surface for cell attachments and cells become unevenly distributed along the surface. Also, as the nutrient medium flows through the reactor, nutrients are more available to the cells near the inlet, and as the medium flows to the outlet, metabolic products such as lactic acid accumulate in the medium, undesirably affecting pH and producing other toxic effects on the cells.
Another significant difficulty encountered with these hollow fiber-type cell culture devices concerns the high media circulation rates necessary to supply adequate oxygen to the cells. Specifically, aqueous nutrient media, equilibrated with air, is able to carry 4.5 ml of oxygen per liter (37.degree. C., 760 mm of Hg). This relative inability of aqueous solutions to carry oxygen causes the rate at which oxygen is supplied to the cells to be the limiting step in in vitro cell growth operations. In order to produce high yields of cells and/or cell secreted products, media circulation rates must be increased to provide more oxygen to cells. High circulation rates in turn cause high internal pressure and turbulence which has presented problems in terms of constructing the device on an industrial scale and in propagating mammalian cells whose sensitivity and fragility prohibit the use of too vigorous aeration and/or agitation. Vigorous aeration also causes the denaturation of many biologically and medicinally useful proteins produced by cell cultures.
Moreover, the above-described hollow fiber-type devices which provide for separate oxygen and nutrient media delivery to cells suffer from the additional disadvantages of being mechanically complex, difficult to assemble and being unduly large. Moreover, the dimensions of these devices are not constrained to maintain the growing cells in close proximity to the nutrient media supply source thus causing undesirable nutrient gradients.
Therefore, it has been desirable to provide new cell culturing devices for growing cells in vitro, particularly mammalian cells, which overcome the various difficulties associated with the prior art devices and produce cells and/or cell secreted products more economically and in higher yields. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to the healing of wounds and, more particularly, but not by way of limitation, to methods, articles, and systems for closing wounds that is compact, self-contained, and includes a disposable wound fluids canister and a porous pad, which is biocompatible with the wound tissue to facilitate the healing of wounds, but does not adhere to the healing tissue.
2. Description of Related Art
Wound closure involves epithelial and subcutaneous tissue adjacent to the wound migrating towards the center of the wound until it closes. Unfortunately, closure is difficult with large wounds or wounds that have become infected. In such wounds, a zone of stasis (i.e. an area in which localized swelling of tissue restricts the flow of blood to the tissues) forms near the surface of the wound. Without sufficient blood flow, the epithelial and subcutaneous tissues surrounding the wound not only receive diminished oxygen and nutrients, but are also less able to successfully fight bacterial infection and, thus are less able to close the wound naturally. Such wounds have presented difficulties to medical personnel for many years.
The most common technique for closing open wounds has been the use of sutures or staples. Although such mechanical closure techniques are widely practiced and often effective, they suffer a major disadvantage by providing tension on the skin tissue adjacent the wound. That is, the tensile force required to achieve closure using sutures or staples causes very high localized stresses at the suture or staple insertion point. Such stresses commonly result in the rupture of the tissue at those points, which can eventually cause dehiscence in wounds, providing additional tissue loss.
Moreover, some wounds harden and inflame to such a degree due to infection that closure by stapling or suturing is not feasible. Wounds not reparable by suturing or stapling generally require prolonged hospitalization with its attendant high cost, and major surgical procedures, such as grafts of surrounding tissues. Examples of wounds not readily treatable with staples or sutures include large, deep, open wounds; decubitus ulcers; ulcers resulting from chronic osteomyelitis; graft site wounds; and partial thickness burns that subsequently develop into full thickness burns. The use of skin grafts in these situations can result in the encapsulation of bacteria and other impurities.
One solution to the problem of non-healing wounds has been demonstrated by applying a continuous negative pressure to the wound over an area sufficient to promote migration of epithelial and subcutaneous tissue toward the wound. A porous pad or other manifolding device may be used to distribute reduced pressure to the wound. The porous pad typically contains cells or pores that are capable of distributing reduced pressure and channeling fluids that are drawn from the wound. One drawback, however, to current designs is that new tissue growth may easily penetrate the cells or pores and effectively attach the pad to the wound. Upon removal of the pad from the wound, any tissue in-growth that has occurred must be physically separated from the pad. Typically, the pad removal involves tearing of new tissue, which not only disrupts the healing process but also may cause discomfort to the patient. | {
"pile_set_name": "USPTO Backgrounds"
} |
As smart phones and other portable devices increasingly become ubiquitous, and data usage increases, macrocell base station devices and existing wireless infrastructure in turn require higher bandwidth capability in order to address the increased demand. To provide additional mobile bandwidth, small cell deployment is being pursued, with microcells and picocells providing coverage for much smaller areas than traditional macrocells.
In addition, most homes and businesses have grown to rely on broadband data access for services such as voice, video and Internet browsing, etc. Broadband access networks include satellite, 4G or 5G wireless, power line communication, fiber, cable, and telephone networks. | {
"pile_set_name": "USPTO Backgrounds"
} |
(a) Field of the Invention
This patent relates to satellite navigation, and more particularly to a new kind of mechanical buffer based polarization-maintaining photonic crystal fiber (PM-PCF) with low magnetic sensitivity for the fiber optic gyroscope (FOG) application.
(b) Description of the Related Art
Compared with conventional optical fibers, the photonic crystal fiber (PCF) contains many silica-air microstructures in its core region, which determine the fiber's optical characteristics. Therefore, by adjusting the geometric parameters of these microstructures, the PCF could be flexibly designed for the given purpose. FIG. 1 shows the PM1550-PCF 10a, which contains in the core region 11 (at least) three layers of air-holes 111 with diameter d and spacing Λ, while two air-holes 112 are enlarged to diameter D.
The arrangement of air-holes in the core region decides the fiber's optic parameters. During the fabrication process of the fiber optic gyroscope, the fiber could suffer from coiling, bending, twisting and temperature-induced stress, which will change silica's refractive index (elasto-optical effect), and affect the PCF's optical characteristics. FIG. 2 shows two kinds of forces on the fiber. Because of the low mechanical strength of silica, when the fiber is under external force, the refractive index of the silica will vary due to the elasto-optical effect. What's more, the arrangement of air-holes in the core region will be changed as well. Thus the fiber's optical characteristics are no longer reliable.
The factors above will influence the PCF's performance, increasing the fiber's magnetic sensitivity and magnetic errors. So far, the general solution to this problem is provided by adding a magnetic shield, which accounts for more than ⅓ of the weight in some small or medium gyroscopes, thus greatly restricting the application of the fiber optic gyroscope. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a microstrip antenna particularly of the type used in aircraft and space vehicle applications.
Microstrip antennas have a number of favorable properties which makes them attractive to the aerospace industries. These include flat and therefore thin constructions, economical as well as accurate manufacture including faithful reproduction of the radiating geometry, particularly under utilization of lithographic methods. Moreover, group array or antennas can be realized in conjunction with a feeder network under utilization of the same substrate. For these reasons this particular type and kind of antenna is quite attractive for employment in active group array or antennas.
On the other hand it has to be considered that the conventional antenna construction features small distance between radiating element and the conductive base plate which is detrimental for the efficiency of radiation; also detrimental are the permissible dimensions and material tolerances as far as properties and physical constants are concerned. Increasing the relevant distances by choosing a thicker substrate material is disadvantaged by a commensurate increase in weight. Also the portion of power conducted through surface waves will also be larger with increasing thickness of the substrate material which on the other hand reduces efficiency and deteriorates the radiation pattern.
Some of the drawbacks could be offset by choosing a substrate with a lower density of material or one could use a multilayer or multiply material which in overall dimensions is thicker but has air or vacuum strata in between. Still alternatively, one could use foam or honeycomb support structures. In all these cases the weight is actually reduced and also the surface wave conduction is reduced but on the other hand it was found that there was an increase in undesirable parasitic radiation from the feeder lines. Feeding electrical power now becomes a problem owing to larger distances between the radiating elements and the base plate in the antenna structure. Here parasitic radiation obtains which of course is undesirable.
The maintaining of an accurate distance between the plane of radiation and the base plate in an antenna structure moreover requires, particularly in the case of a compound substrate under utilization of air or vacuum, a particular support structure. In the case of active antennas for space vehicles moreover it is necessary that these materials have a good thermal conductivity in order to provide for heat removal from the transmitter and for receiver modules arranged on the base plate and adjacent the antenna's front side. In the case of substrates which are thin in material such a thermal conductivity is simply not present particularly in those cases where there is a vacuum area included in the substrate.
German printed patent application 28 16 362 proposes a microstrip antenna which is comprised of a multiplicity of small cavity resonators for the purpose of providing certain resonance effects. The cavities are formed in that the radiators have a specified distance from the base plate. However, the problem area mentioned above namely efficiency vs weight vs heat conduction is not dealt with at all in that particular application. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates generally to Web servers, and particularly to solving resource leaks in Web servers.
The recent rapid increase in the demand for network services has caused a similar increase in the number and complexity of Web servers produced to serve that demand. Due to this complexity Web servers are exhaustively tested in development before being taken into production, where they serve customers in real time. But once in production, Web servers can be difficult to test, and the problems revealed can be difficult to solve. One common problem is the resource leak, where some resource, such as memory, is gradually consumed in a manner that is detrimental to the stability or performance of the Web server. One common resource leak is the memory leak.
Web servers provide information components, such as Web pages, word processing documents, spreadsheets, images, movies, and the like, to customers. Some of these information components are static, and therefore can be provided without further processing. Other information components are dynamic, and must be generated by an information component generation process before delivery to a customer. A resource leak is caused when the resource is marked as “in use” while the information component generation process is working, but is not released when the process no longer needs that resource. The resource may be memory, synchronization objects, communication ports, or other finite computer resources. Because the resource is never released, it is not available for use by the same or other processes. Over time, such resource leaks can cause the process or whole operating system to malfunction.
Resource leaks in production Web servers are typically very time consuming and difficult to diagnose and correct.
First, resource leaks often happen very slowly, so days or weeks are spent collecting data to evaluate the effectiveness of each proposed solution. If many solutions must be tried, this process can consume months or more.
Second, resource leaks often happen on production Web servers. Because these Web servers must be highly reliable, personnel diagnosing the resource leak may not be allowed to significantly modify the system. One common way of diagnosing a resource leak is to disable a part of the leaking process. Parts are individually disabled and enabled. When the resource leak is seen to disappear, the parts that are disabled are usually responsible for the leak. This strategy is generally disallowed on production Web servers, since the loss of functionality associated with disabling components is unacceptable. Other diagnostic software components are often used to detect and diagnose resource leaks. Tools such as leak detectors can be very valuable when finding small leaks, but the use of these tools on production servers is often forbidden. Administrators responsible for the stability of production Web servers do not want to put that stability in jeopardy by running additional diagnostic and debugging software on the Web server.
Third, resource leaks are often associated with unusual or unexpected circumstances. Most software systems used on production Web servers have undergone significant testing before being deployed. Therefore, leaks associated with commonly used features of the Web server are unusual. Those leaks are typically found and corrected before deploying the software. When a leak is found on a production Web server, it is frequently associated with a feature that was not heavily tested, perhaps because it didn't seem important, or because the particular sequence of user actions was not predicted. Identifying a resource leak on a production Web server is generally pretty easy. The resource is observed to be exhausted. Identifying the cause of the resource leak is much harder, since it's typically NOT associated with any common functionality. Typically, when a flaw or bug is found in software, the circumstances that lead to the display of the flaw are reproduced in a laboratory. Once a fix has been proposed, that fix is implemented and tested in the laboratory. This model doesn't work well for leaks detected on a production system, since reproducing the circumstances of the production system in a laboratory is difficult. The usage characteristics of a production system are complicated and difficult to characterize. | {
"pile_set_name": "USPTO Backgrounds"
} |
In acoustic sensing of subterranean formations, a transmitting source in the borehole can be used to create pressure waves that travel through the formation and are recorded at a number of receivers. The pressure wave-train can be very complex. For example, in a fast formation the recorded wave-train from a monopole source may consist of a compressional wave, a shear wave, a Stoneley wave, and a pseudo-Rayleigh wave. These waves are referred to as primary or “direct” waves. In conventional acoustic processing, receiver waveforms are processed using semblance techniques to extract formation properties from the direct waves such as compressional and shear wave velocities.
In a borehole environment, the wave-train also contains coherent reflection events from bedding planes, planar fractures, and clean borehole breakouts. These events are referred to as ‘secondary’ waves because they are usually much smaller than the direct waves. In addition to the secondary waves, incoherent scattering events occur due to borehole rugosity, road noise or drilling noise, and scattering from complex geological structures such as non-planar fracture networks. In conventional acoustic processing, the reflections and scattering are treated as noise and the semblance techniques are applied to reduce their effect on the measurement of the formation properties from the direct waves. Known techniques can include the use of one-dimensional (1D) wave separation in the frequency domain to estimate the direct waves. The wave separation treats the direct waves as the signal and the reflected waves as incoherent noise, which is averaged out during the wave separation. The estimated direct waves are subtracted from the original waveforms to estimate the reflected waves. In such techniques, uniform depth spacing is also assumed and aliasing errors are ignored. This subtraction method can suffer from large residual errors in the reflected wave estimate because the reflections are typically much smaller than the direct waves. The residual errors are reduced after wave separation by stacking the waveforms in the time domain using an expected time of arrival estimate from ray tracing theory. However, the usefulness of such measurements and analysis may be related to the precision or quality of the information derived from such measurements. | {
"pile_set_name": "USPTO Backgrounds"
} |
Puzzle games and construction toys can be used for developing spatial thinking and spatial imagination of players or as educational visual aid when teaching combinatorial analysis, stereometry or other educational disciplines. In particular, while assisting with visualization of sections for spheroid (spherical) or obloid objects, it is useful to consider whether it is possible to break a ball into a finite number of equal parts in such a way that at least one of the parts does not contain the center of the ball on the border or inside. | {
"pile_set_name": "USPTO Backgrounds"
} |
The public interconnected computer networks—commonly called the Internet and colloquially called the web—have made possible a number of applications that were hitherto unthinkable. In general, a user visits web pages using a browser program executing on a client computer. When the user visits a web page, a document such as a news article, a downloadable file such as an e-book, downloadable software programs such as those available at www.shareware.com, a piece of music, a graphical image or other such object that is of interest, it may be a case that the user prefers to read or refer to the object at a later date. Currently the user has several choices—he can print the web page, download the page to his client computer, or make a book mark to enable an easy return to the web site for reference at a later date. But there are problems with each of these methods.
Printing every web page that is of interest quickly becomes unmanageable. A product called SurfSaver™ is a browser add-on, which lets a user to store Web pages directly from the browser into searchable folders on the user's client computer. While SurfSaver™ can be used to organize and search the information the user gathers on the Internet, it requires the user to download software to the client computer and create an information store for web pages downloaded to the client computer. But such downloading of web pages, documents, or files may consume significant resources on the client computer, and these downloaded web pages or files may not be readily available in a form that can be shared by others.
Book marking the web page or the location is a better solution than the above two methods. A typical bookmark comprises a location or address, usually specified in a Universal Resource Locator format, and a mnemonic so that the user remembers what information is stored at the location. In general, the browser program stores bookmarks in a special “book mark” file on the client computer. The location of this bookmark file is typically known to the browser, which loads the contents of the file and presents the bookmarks to the user when he makes an appropriate selection on the browser. Examples of such book marking methods are found in the commercially available browser programs such as Internet Explorer™, in which program the bookmarks are called “Favorites.”
Often, it is the case that either the bookmarks are too many or they become “stale.” Bookmarks become stale when a site to which the bookmark points no longer hosts the web page addressed by the bookmark. The user, who depended on the availability of the information online, is now left with a bookmark that does not point to useful data.
Additionally, sharing information with others either in a controlled manner or with a widespread audience is becoming an increasing need. Sharing information that is restricted as to the number of copies that can be made without infringing an author's or a publisher's rights is becoming important, There is a need, therefore, for a method and system to improve the state of the art to address these and other issues. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to a double or dual slide projector having two projector assemblies combined in a single appliance. Each projection assembly preferably includes a light source, condenser lens, and slide frame, and the projection assemblies are arranged parallel with each other and movable between two positions for projection and slide change. One possible arrangement for such a double slide projector is shown in my U.S. Pat. No. 3,847,472, issued on Nov. 12, 1974.
The double slide projector in which the invention occurs also uses a common magazine for slides, and a common slide changer for moving slides back and forth between the magazine and the projection assemblies. Slide changing occurs along a slide change plane between the magazine and slide frames of the projection assemblies, when the projection assemblies are in their axially rearward position to locate their slide frames on the slide change plane. The magazine proceeds in a "pilgrim step" motion of advancing two steps and retracting one step so that slides alternately moved into the projection assemblies are returned to the magazine in their original sequence. Such a motion is described in my parent application U.S. Pat. No. 725,140. The magazine is preferably movable along a path adjacent the projection assemblies so that one of the projection assemblies is more remote from the magazine and the other projection assembly is nearer the magazine.
Such a double slide projector requires a simple and reliable slide changer mechanism for alternately moving slides back and forth between the magazine and the remote and nearer projection assemblies. This is solved according to the invention with a slide changer having full-stroke and partial-stroke motions for gripping and moving slides alternately between the different distances required. The invention also aims at simplicity, economy, reliability, and quiet and trouble-free operation in a slide changer producing the required slide movement for a double slide projector. | {
"pile_set_name": "USPTO Backgrounds"
} |
Software developers often encounter problems with memory resources due to subtle coding errors. Typical memory management problems include memory leaks, memory overruns, lack of memory, and de-allocation errors. With such memory management problems, applications can crash, making debugging efforts difficult. | {
"pile_set_name": "USPTO Backgrounds"
} |
Refrigerator appliances generally include a cabinet that defines a food storage chamber. In addition, refrigerator appliances also generally include a door rotatably hinged to the cabinet to permit selective access to food items stored in the food storage chamber. Certain refrigerator appliances, commonly referred to as door-in-door refrigerator appliances, may also include an outer door rotatably hinged to the inner door to permit selective access to the food storage chamber or, alternatively, a food storage chamber positioned between the inner and outer doors. In addition, door-in-door appliances may also include a gasket positioned on the outer door. Thus, when the outer door is in the closed position, the gasket seals against the inner door to enclose the food storage chamber.
For some refrigerator appliances, a door is provided that includes multiple attached pieces. In some instances, it may be desirable for certain pieces to be formed from a different material from the rest of the door and provide a surface that enhances the appearance and usability of the door. In order to join the separate pieces panel to the rest of the door, some existing refrigerator appliances use one or more adhesives. However, this configuration may present a number of issues or drawbacks, especially for pieces forming an inner surface of the door. As an example, the material of an inner surface may expand/contract at a different rate than the piece or material to which it is attached (e.g., by an adhesive). Over time, the difference in expansion/contraction may deteriorate the bond between the adhesive, door, and separate panel. Even if adhesives are not used, the separate panel may bend or buckle as it expand/contracts differently from the rest of the door.
Accordingly, further improvements are necessary to address one or more of the above-identified issues. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The current invention relates to drivers for resistive loads, and in particular to drivers that control the brightness of a liquid crystal display (LCD) backlight system by regulating the electrical current through an LED array.
2. Description of the Related Art
A growing number of electronic devices use LCDs to provide information to the user. LCDs work, generally, by permitting or preventing light from passing through electrically controlled “portholes.” Three categories of LCD displays are reflective, transmissive, and transflective. The light necessary for the LCD display to be visible can be provided by reflected ambient light, as in reflective LCD displays. In many situations, particularly where ambient light is meager, it is advantageous to provide a backlight for the LCD, as in transmissive and transflective LCDs, to make the display easier to read.
Transmissive LCDs, such as LCD computer monitors, are only used with a backlight. Transflective LCDs, such as those used on many popular portable audio devices, can be used either with a backlight (as in a transmissive LCD) or with reflected ambient light (as in a reflective LCD display). One type of backlight for transmissive displays (as used herein, the term includes transflective LCDs in transmissive mode) is based on an array of light emitting diodes (LEDs).
The brightness of a transmissive display that uses an LED-array backlight can be varied by controlling the amount of current flowing through the LEDs. The higher the current, the brighter the transmissive display appears. In order to control the current through the LEDs, a feedback loop is typically used. The feedback loop includes a current-sense resistor, i.e., a resistor of relatively low resistance connected, on one end, to a device of interest, e.g., the LED array, and, on the other end, to a common node (e.g., ground), wherein the voltage across the resistor is indicative of the current through it and thus through the device of interest. This method is considered sufficiently reliable for current values down to the tens of milliamps. However, prior-art backlight drivers do not reliably detect smaller electrical currents, such as those measured in microamps, since smaller voltages are more difficult to accurately detect. | {
"pile_set_name": "USPTO Backgrounds"
} |
In wireless receivers, a wide range of signal levels needs to be handled. Some of the reasons for this wide range of signal levels are that changes in the path loss are frequent and so are changes in distance from the transmitter to the receiver. One of the most common methods of accommodating this high dynamic range requirement is to use a variable gain element. This element (or elements), with some control circuitry, acts in such a manner that the signal level at the receiver output is kept constant.
One method of implementing a variable gain element known to those skilled in the art is Lo use dual-gain emitter-coupled differential pairs. This method is shown on page 46 of "RF-Heterodyne Receiver Design Technique for Digital Cellular Wireless Systems" published in 1995 by Josef Fenk of Siemens. This publication is hereby incorporated by reference. With one single amplifier stage, two different values of gain may be realized In order to accomplish multiple gains, several stages of dual-gain amplifiers are stacked in series. This method is also well known to those skilled in the art. With this method, stacking three dual-gain amplifiers cells in series will result in eight different gain values. Several points should be noted concerning this realization. First, in order for it to work, it is necessary that proper DC level shifting be performed at the interface of different dual-gain amplifiers. Second, when this circuit is in operation, one differential pair in each dual-gain cell must be turned on for each gain setting. This results in unnecessary power consumption.
Thus, there exists a need in the industry to provide an improved switchable gain amplifier particularly well suited for an environment where multiple levels of gain are required. | {
"pile_set_name": "USPTO Backgrounds"
} |
Vacuum heat treating furnaces which employ electrical resistance heating elements are well known. Popular designs are presented in U.S. Pat. Nos. 4,559,631 and 4,259,538.
A typical vacuum furnace has a furnace wall and a hot zone chamber of a circular cross-section which houses a series of banks of axial-spaced electrical resistance heating elements suspended from an inner wall of the hot zone chamber by a series of support rods. A heating element is generally made from graphite or molybdenum alloy, and generates radiant heat in response to electrical current passing therethrough.
Over the life of an average furnace the heating elements are subjected to many expansions and contractions as a result of hundreds of heating and cooling cycles. Since only the ends of each of the elements is fixed, these heating and cooling cycles can cause the elements to undergo deformation. As a result of this deformation, the heating elements tend to bow. Stress caused by such deformation can also result in fractures which in turn necessitate replacement of the heating elements. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to an indicating instrument for an automobile which has a light conductive pointer illuminated by a built-in light emitting element.
2. Description of the Related Art
U.S. Pat. No. 5,142,453, which corresponds to Japanese Utility Model Unexamined publication Hei 3-63821, discloses an indicator in which a light emitting element is disposed at an end of a pointer driving shaft. A light receiving portion of the pointer is carried by a fixture which is driven by the driving shaft.
However, since the light emitting element is disposed at a center of rotation of the fixture, an illuminating portion of the pointer is limited and the pointer is not sufficiently visible in the dark.
Japanese Utility Model Unexamined Publication Sho 64-10625 discloses an indicator which has an LED disposed outside the indicator and a pointer which has a toothed bottom surface. The toothed surface reflects light upward from its internal inclined surfaces and increases the luminance of the pointer upper surface which is the illuminating surface.
However, if light enters the pointer from upper outside thereof when the LED which is not energized, the pointer is illuminated by the light from the outside since it is reflected from the toothed surface and illuminates the pointer in the same manner as mentioned above. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to an adaptor device for electrode catheters, in particular for unipolar electrode catheters.
The art field of heart surgery embraces numerous types of cardiac catheter designed for connection at one end, generally by way of a flexible tube functioning as a biocompatible outer sheath, to an artificial pacemaker implanted in the body of the patient, and carrying a terminal electrode at the remaining end which is offered in direct contact (positively anchored in most instances), to the ventricular cardiac muscle.
In the particular case in point, the expression `unipolar` is used to describe a catheter of which the terminal electrode constitutes the negative pole or cathode of the cardiac pacemaker, and the positive pole or anode is provided by the casing of the pacemaker itself. The terminal or ventricular electrode consists in a sharp point, preferably affording elements such as will penetrate and thus establish a continuous and secure contact with the cardiac muscle, connected to the negative pole of the pacemaker by way of an electrically conductive spiral wound wire (e.g. platinum-iridium alloy). It is being found currently, where patients require the replacement of an existing pacemaker rendered unreliable by reason of its low charge, irregular operation or malfunction, that problems can arise due to incompatibilities between the connectors of electrode catheters implanted in the past and those of more recent design; reflecting the ever greater technological advances being made in this field, in effect, the newer catheters are much smaller than their predecessors as the overall dimensions of the newer pacemakers also become much smaller.
Remembering that the ventricular electrode becomes embedded in time beneath a layer of organic tissue and cannot be removed (such a step is inadvisable from the medical standpoint), it happens that the solution adopted in present-day surgical practice is almost invariably one of implanting a completely new electrode catheter in the cardiac cavity for connection to the new pacemaker, and simply leaving the former electrode in place, unused, alongside the replacement.
As an alternative expedient, the prior art embraces adaptor-reducer type connectors functioning as a mechanical interface between the existing pins of a previously implanted electrode catheter and the receiver contacts of a replacement pacemaker; this inevitably reflects a compromise, from technical and medical standpoints alike, as the new implant is impoverished somewhat by the large dimensions of the mechanical components used for the interface. Given the reliance of the patient on the pacemaker, moreover, artificial stimulation must be maintained for the maximum time possible whichever replacement technique is ultimately adopted; accordingly, any replacement operation, and especially the fitment of a mechanical adaptor, must be accomplished as swiftly as possible.
The object of the present invention is to overcome the problem outlined above by providing an adaptor device that can be secured to the unattached end of a unipolar electrode catheter already in situ and used to make the requisite electrical connection to pacemakers of the latest generation; such a device will be simple in embodiment, swiftly implanted in surgery, and able to ensure a suitably dependable connection. Equally, this same object embraces the creation of an electrode catheter with a terminal portion readily adaptable to the markedly compact pacemakers of the latest generation. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present disclosure generally relates to a network reliability evaluation method and a system thereof, in particular to a network reliability evaluation method for acyclic network and a system thereof.
2. Description of the Related Art
At present, many systems, such as computer and communication systems, power transmission and distribution systems, transportation systems, and oil/gas production systems, can be modeled as networks in the planning, designing, and control of systems. The conventional networks have a source node, some junction nodes and sink nodes. The information transmitted in the networks originates from the source node and the junction node plays the role of the transmission in the network, wherein the junction node transmits information through the arc. Finally, the information is transmitted to different sink nodes. Evaluating the probability of connecting the source node to the sink nodes is defined as the reliability evaluation of the network. The reliability evaluation is applied to be an important indicator for evaluating the network performance.
The network reliability evaluation method is executed after all the minimal paths (MP) or all the minimal cuts (MC) are found. Generally, the method of using the minimal path is better than that using the minimal cut intuitively. In terms of the conventional networks, the methods of searching all the minimal paths are executed based on the arcs, which is more complicated.
The acyclic network plays a crucial role in the various networks. In the binary-state and acyclic networks, all the arcs have working state and failed state, and the connections among the nodes do not have the parallel arcs and are free of the self-loop. Generally, the networks formed of the information set in sequence can be defined as the acyclic networks.
For example, the applications of scheduling problems, data compression, data backtracking, data processing networks, and so on all have the probability of being the acyclic network. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to wire bonding to bond pads on semiconductor chip packages and in particular to bond pads which have been coated with palladium.
The art of making an electrical connection to a semiconductor chip by wire bonding from a bonding pad on the chip to a corresponding pad or lead on a chip carrier is widely known and practiced in the semiconductor industry. While it has been found to be advantageous in some applications to manufacture chip carriers using conventional organic dielectric material such as epoxy-glass layers and conductive layers of copper, wire bonds made to a copper pad typically fail due to formations of a brittle intermetallic alloy which forms between the wire material, usually gold and the copper pad. Accordingly, one typical practice in the art is to plate a bond pad with a thin layer of nickel followed by a thicker layer of gold prior to bonding a gold wire thereto.
A nickel layer of about 150xc2x150 micro-inch thickness provides a satisfactory diffusion barrier to prevent the formation of copper-gold intermetallic alloys between the copper pad and the gold layer. The gold layer then provides a satisfactory surface for making conventional wire bond connections. A fairly thick layer of gold, typically greater than fourteen micro-inches is needed for satisfactory bonds with gold wire of 0.8 to 1.5 mili-inch diameter.
Palladium has been used as a lower cost substitute for the gold layer; however, it has been found that the palladium must be heated to relatively high temperatures, e.g., above 200xc2x0 C., in order to make satisfactory bonds. Because epoxy-glass materials do not tolerate such high temperatures, various attempts have been made to make wire bonds to palladium coated pads, with a nickel diffusion barrier beneath the palladium, without success.
Gillum et al., in xe2x80x9cWire Bond Evaluation Reportxe2x80x9d by National Center for Manufacturing Sciences, Apr. 30, 1996, reports on p.13 that palladium surfaces give poor results, with many initial incomplete bonds being formed.
SMT Trends, Jan. 22, 1996 reported satisfactory bonds in a preliminary study xe2x80x9cElectroless Palladium: A Surface Finish for Interconnect Technologyxe2x80x9d; however, the bonding temperature used was not reported.
It has been suggested in Japanese patent JP-8139148A that the bondability of a palladium layer over copper can be determined prior to bonding, by measuring how much copper has diffused up through the palladium layer. When a nickel barrier layer is placed under the palladium, bonds made at temperatures below 200xc2x0 C. fail.
Consequently, palladium has not been used to coat wire bond pads on organic dielectric chip carriers even though palladium has been found to be a satisfactory substitute for gold in coating pads which are used for mounting components by soldering. Where both wire bond chips and soldered components are to be mounted on a single carrier, the use of palladium for both types of bonding pads would be advantageous over using separate metallurgies or the more costly use of gold for both pads, as is the current practice.
It is, therefore, an object of the invention to enhance the semiconductor chip packaging art by providing an enhanced method for bonding wiring to a metal surface on a package, chip, or any other conductive element in the art.
A further object of the invention is to provide an electrical card structure having enhanced bondable pads for receiving conductive wiring.
These and other objects are attained in one embodiment of the invention wherein there is provided a method of forming a bondable metal surface by providing a layer of a first metal, applying a thin layer of a second metal to the first metal layer, and heating the first and second metal layers to a predetermined temperature for a predetermined time. The method may also include the step of bonding a wire to the layer of first metal with the thin layer of second metal thereon.
In accordance with another embodiment of the invention, there is provided an electrical card structure comprising a circuitized substrate having at least one wire bond pad located thereon, a layer of a first metal located on the wire bond pad, and a thin layer of a second metal on the layer of first metal. The electrical card structure may also include a wire bonded to the layer of first metal with a thin layer of second metal located on the first metal, the bond occurring through the thin second layer. | {
"pile_set_name": "USPTO Backgrounds"
} |
Often used in a conventional air conditioning apparatus or the like is a finned tube heat exchanger (i.e., cross fin-and-tube heat exchanger) provided with heat-transfer fins disposed along an airflow, and a plurality of heat-transfer tubes inserted into the heat-transfer fins and arranged in a direction substantially orthogonal to the direction of airflow. Therefore, a method using cut-and-raised machining is sometimes adopted in a finned tube heat exchanger for enhancing heat transfer by forming parts that are cut, raised up, and opened toward the upstream side of the airflow direction in positions of the heat-transfer fin surfaces on the two sides of the heat-transfer tubes, for the purpose of renewing the boundary layers on the heat-transfer fins and reducing the dead water regions formed in parts of the heat-transfer fins downstream of the heat-transfer tubes in the airflow direction (see Japanese Laid-open Patent Application No. 61-110889). | {
"pile_set_name": "USPTO Backgrounds"
} |
German Patent DE 198 17 714 discloses a method for measuring the position of structures on a mask surface, wherein the mask is positioned in an image-evaluating coordinate measuring device on a measurement table displaceable in a direction perpendicular to the optical axis of an imaging measurement system in an interferometrically measurable way. A mask coordinate system associated with the mask is aligned relative to a measuring device coordinate system with the help of alignment marks. The desired position of the structures is given in the mask coordinate system. A coordinate position of two outer edges of the mask, which are perpendicular to each other, is measured in the mask coordinate system. For this purpose, the distances from two structures to an outer edge and from one structure to the other outer edge are determined.
German published patent application DE 198 25 829 discloses a method for determining the position P of a structural element non-orthogonal to the coordinate axes (x, y) of a substrate. The structural element is imaged onto a detector array of a CCD camera including a reference point. With the help of a measurement window rotated at an angle Θ with respect to the coordinate system, the position of an edge of the structural element relative to the reference point is determined. The position L of the reference point relative to the origin of the coordinate system is determined based on the angle Θ and the current measurement table coordinates, so that the position P is obtained. Determination of centrality is not included.
A measuring device for performing such a method is described with its basic elements in the lecture script “Pattern Placement Metrology for Mask Making,” Dr. C. Bläsing, Semicon Geneva, Education Program, issued on Mar. 31, 1998. The measuring device particularly serves for controlling the quality of masks for the semiconductor production. The quality of the mask is gaining more and more importance in type production. The specifications for the positions of the structures (pattern) from one mask to the other are becoming tighter and tighter. The measuring device described in the lecture script may measure the position of the structures relative to defined alignment marks, which define the mask coordinate system, with an accuracy of typically less than 10 nm. With the help of these alignment marks, the masks may be aligned in the stepper for the projection on wafer surfaces. Errors made in this process are directly added to the error budget of the lithography process. The mask is aligned in the stepper such that the respective alignment marks are positioned exactly one on top of the other during exposure. However, the steppers only have a certain area in which the mask may be shifted and/or rotated for physical alignment. The centrality of the masks is defined by the position of the pattern on the mask and thus determines the central position of the pattern (for the exposure of the wafer) within the mask.
German published patent application DE 10 2004 055 250 A1 discloses the inspection of a wafer, wherein a wafer-to-wafer comparison is restricted to predetermined compared regions selectable by the user. Only areas of a wafer are compared. This does not include the determination of coordinates and/or relative positions within predetermined coordinate systems.
European Patent EP 0 105 611 B1 discloses a device for inspecting structures applied to a mask for the semiconductor production. The patent is directed at the measurement of the structures on the mask rather than at the actual alignment.
U.S. Pat. No. 4,586,822 discloses a method for inspecting a mask for the production of a semiconductor device. The alignment marks on the mask are used to align the mask and the wafer such that structures may be exposed in an exact position with respect to each other. The result of the exposure on the wafer is also inspected to find defects and/or foreign particles on the mask. This method is not beneficial to achieving a high throughput in mask measuring.
U.S. Pat. No. 4,388,386 discloses a method with which insufficient matching of a mask set may be reduced to a minimum. Each mask of the set is compared to a known standard. Again, determination of centrality is not included. The position of structures with respect to the edges of the mask is not determined.
As specifications for all components become tighter and tighter, the position of the structures relative to the outer edge of the mask has turned into an important quality criterion of the mask. The exact rectangularity of the mask is no longer a negligible quality criterion either. Previously, the outer edges of the masks were assumed to meet at a right angle. As the accuracy of the coordinate measuring machine increases, the exact rectangularity and/or deviations from rectangularity where the outer edges meet also have come to play an important role.
The rectangularity of the outer edges and/or the knowledge about deviations of the outer edges from rectangularity play an important role because, in the lithography device (such as e-beam or laser lithography), the mask is normally contacted in three places to obtain a reproduced position. The three points define the two outer edges of the mask. The outer edges of the masks are assumed to be at a right angle with respect to each other. If this is not the case or if the non-rectangularity of the outer edges influences the result of the lithography, it is necessary to know about the rectangularity or non-rectangularity of the outer edges. Only in this way these edges may be used as reference for the pattern generated on the mask by the structures.
However, each new chip generation has increased requirements regarding accuracy and measurement throughput. The accuracy achievable by manual measurement using a conventional microscope is no longer sufficient. In addition, the manual measurement requires a lot of time for the alignment in the measuring device, the locating of the structures and the actual measuring. Therefore it is particularly important that measuring the structures on the surface of a mask and determining the rectangularity of the outer edges with respect to each other may be performed in one measuring device. If this is the case, the mask does no longer have to be transported from one measuring device to the other, which ultimately represents an error source for damage to the mask. Furthermore, the time required for temperature adaptation of the mask may be avoided if the measurement takes place in a single device. | {
"pile_set_name": "USPTO Backgrounds"
} |
CDMA is widely used in cellular and other wireless systems for multiplexing communications among multiple users on a common frequency band. In direct-sequence (DS) CDMA, the transmitter multiplies each user's signal by a distinct code waveform. The code waveforms of the different users have the form of “pseudo-noise” (PN) sequences, also known as spreading codes, and are chosen so as to be as much as possible mutually orthogonal. The receiver receives a composite signal made up of the sum of all of the users' signals, which overlap in time and frequency. To recover the individual signal of a given user, the receiver correlates the composite signal with that user's distinct code.
Multiple access interference (MAI) limits the capacity and performance of DS-CDMA systems. MAT results from the lack of complete orthogonality between the spreading codes, due to random time offsets between the signals of different users, for example. MAI becomes increasingly problematic as the number of interfering users and their power increases, particularly when there are power imbalances among the users. These imbalances typically result from differences in distance between the users and the base station, as well as from fading and other factors that affect signal power. The problems caused by MAI have led a number of groups to develop multi-user detection techniques, in which information about multiple users and their respective code waveforms is used jointly to better detect each individual user. A survey of these techniques is presented by Moshavi in “Multi-User Detection for DS-CDMA Communications,” IEEE Communications Magazine (October, 1996), pages 124–136, which is incorporated herein by reference.
To formulate the multi-user detection problem, we consider a CDMA receiver that receives signals from K users. The received complex-envelope baseband signal x(t) is a superposition of the users' individual signal waveforms, including channel distortion and additive noise n(t):
x ( t ) = ∑ k = 1 K h k ( t ) * ξ k ( t ) + n ( t ) ( 1 ) Here “*” denotes convolution, and hk(t) is the impulse response of the kth user channel (including delay, attenuation, multipath and filtering effects). In the derivation that follows, n(t) is assumed to be Gaussian with mean zero and without correlation between successive noise samples.
The kth user's signal waveform is given by:
ξ k ( t ) = ∑ m = - ∞ ∞ b k ( m ) p Tb ( t - mT b ) c k ( t ) ( 2 ) In this equation, bk(m) is the mth symbol transmitted by the kth user, wherein bk is selected from a predefined constellation (or alphabet) A. In phase-shift keyed (PSK) modulation, the alphabet set lies on the unit circle in the complex plane. For example, in quadrature phase shift keying (QPSK), A={−1, −j, 1, j}. For binary phase shift keying (BPSK), which is currently the most common modulation scheme in current cellular systems, bk is a bit selected from A={−1,1}. Tb is the symbol duration, and pT(t) is a rectangular pulse with unity value in tε[0,T), and zero elsewhere. ck(t) is a complex-valued PN spreading waveform, with a chip period Tc=Tb/N, wherein N is the spreading response of the DS modulation:
c k ( t ) = ∑ i = - ∞ ∞ 1 2 [ γ k ( I ) ( i ) + j γ k ( Q ) ( i ) ] p Tc ( t - iT c ) ( 3 ) γk(I)(i) and γk(Q)(i) are independently drawn from {−1,1} with uniform distribution.
The multi-user detection problem can be stated as follows: Let the received signal x(t) be sampled, and assume that the impulse responses hk(t) and the spreading waveforms ck(t) are known. Now estimate the symbols bk(m) from the samples x(t) for all k and m. For the sake of simplicity in framing the problem, it is assumed that the impulse responses of the channels can be expressed as complex scalars hk, that the user signals are mutually synchronized, and that the samples are taken at mid-chip, at a sampling rate equal to the chip rate (i.e., N samples per symbol). It is possible to relax some of these assumptions and still achieve multi-user detection, as described hereinbelow.
The symbols transmitted by the K users at symbol interval m can be written as a K×1 real vector:b(m):=(b1(m), . . . , bK(m))T (4)The samples taken during the mth symbol interval can be arranged as a N×1 complex vector x(m). Rearranging equations (1) and (2) in similar vector form gives the following expression:x(m)=S(m)b(m)+n(m) (5)Here n(m) is a N×1 complex vector of noise samples. S(m) is a complex N×K matrix, whose kth column is a signature vector sk(m) representing the “symbol signature” of the kth user during the mth symbol interval. The elements of the signature vectors sk(m) are samples of the following waveform:sk(t; m):=hkck(t), mTb≦t≦(m+1)Tb (6)
Given the known elements of x(m) and S(m), in order to solve the multi-user detection problem it is necessary to find the elements of b(m) that best satisfy equation (5). An optimal, maximum-likelihood solution to this problem was framed by Verdu in “Minimum Probability of Error for Asynchronous Gaussian Multiple-Access Channels,” IEEE Transactions on Information Theory 32:1 (January, 1986), pages 85–96, which is incorporated herein by reference. According to this solution, for each m, we find the elements of b within the applicable constellation A that minimize ∥x−Sb∥2. (For brevity, here and below, we write simply b, S and x to represent b(m), S(m) and x(m).) Although optimal, this detector is usually impractical, since it requires an exhaustive search over all possible bεAK.
As a less costly (though suboptimal) alternative, Lupas and Verdu proposed a decorrelating detector in “Linear Multi-User Detectors for Synchronous Code-Division Multiple Access Channels,” IEEE Transactions on Information Theory 35:1 (January, 1989), pages 123–136, which is also incorporated herein by reference. The decorrelating detector finds a vector {tilde over (b)} that minimizes ∥x−Sb∥2 over bεCK, wherein C is the complex plane. The “soft decision” vector {tilde over (b)} is projected onto the constellation AK to arrive at the hard decision output {circumflex over (b)}. For BPSK modulation, the elements {circumflex over (b)}k are given simply by the sign of the real part of the corresponding elements {tilde over (b)}k. Assuming K≦N and full column-rank S, the soft decision solution is given by:{tilde over (b)}=(SHS)−1SHx (7)wherein SH is the conjugate transpose of S.
The decorrelating detector has been found to provide substantial performance responses over conventional single-user detection, with significantly lower computational complexity than the maximum-likelihood detector proposed previously. It performs well even in the presence of substantial power imbalances among the users. It still entails a substantial computational burden, however, in inverting the matrix SHS.
A number of different solutions have been proposed in order to improve multi-user detection performance. For example, Duel-Hallen suggests combining the decorrelating detector with decision feedback, in “Decorrelating Decision-Feedback Multiuser Detector for Synchronous Code-Division Multiple-Access Channel,” IEEE Transactions on Communications 41:2 (February, 1993), pages 285–290, which is incorporated herein by reference. This detector generates decisions {circumflex over (b)}k iteratively, working down from the stronger user signals to the weaker signals. The decisions made with respect to the stronger users are used in forming decisions for the weaker ones. The decision-feedback detector has been found to outperform the original decorrelating detector as long as the bit-error rate (BER) is not too high, and reliable estimates of the channel responses hk are available.
Various other technique have been suggested in the patent literature for canceling interference among the signals received from multiple CDMA users. For example, U.S. Pat. No. 5,644,592, to Divsalar et al., whose disclosure is incorporated herein by reference, describes a method of parallel interference cancellation, which estimates and subtracts out all of the interference for each user in parallel. U.S. Pat. Nos. 5,363,403, 5,553,062, 5,719,852 and 6,014,373, all to Schilling et al., whose disclosures are also incorporated herein by reference, describe methods for solving the (SHS)−1 matrix using a fast polynomial expansion.
Multi-user detection methods generally require that the channel responses hk be known. Typically, the channel responses are not known a priori, but must rather be determined by a suitable channel estimator in the receiver. When short-period, repetitive spreading codes ck(t) are used, subspace-based signal array processing techniques can be used to solve the channel estimation problem. Such techniques are described, for example, by Madhow in “Blind Adaptive Interference Suppression for Direct-Sequence CDMA,” Proceedings of the IEEE 86:10 (October, 1998), pages 2049–2069, which is incorporated herein by reference.
Commercial CDMA standards, such as IS-95, however, use PN spreading codes whose periods are so long that they can be considered purely random for reasonable observation times, rather than repetitive. To address this problem, Torlak et al. offer an iterative approach in “Blind Estimation of FIR Channels in CDMA Systems with Aperiodic Spreading Sequences,” Proceedings of the 31st Asilomar Conference on Signals, Systems & Computers (Pacific Grove, Calif., November, 1997), which is incorporated herein by reference. According to this approach, the receiver alternately estimates the channel responses and, based on these responses, estimates the transmitted signals, until the estimated signals converge. Weiss et al., in “Channel Estimation for DS-CDMA Downlink with Aperiodic Spreading Codes,” IEEE Transactions on Communications 47:10 (October, 1999), pages 1561–1569, which is likewise incorporated herein by reference, describe a sub-space approach for finding an initial estimate of the channel responses, followed by an iterative calculation similar to that described by Torlak et al. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to the field of telecommunications. More particularly, the present invention relates to a telecommunications system for allowing a subscriber connected to the Internet to receive customized audible alerts concerning an incoming telephone call.
2. Acronyms
The written description provided herein contains acronyms which refer to various telecommunications services, components and techniques, as well as features relating to the present invention. Although some of these acronyms are known, use of these acronyms is not strictly standardized in the art. For purposes of the written description herein, acronyms will be defined as follows: Advanced Intelligent Network (AIN) Asymmetric Digital Subscriber Line (ADSL) Central Office (CO) Called Party Number (CDN) Calling Party Number (CPN) Compact Service Node (CSN) Customer Name (CNAME) Customer Premises Equipment (CPE) Digital Subscriber Line (DSL) Directory Number (DN) High Bit-Rate Digital Subscriber Line (HDSL) Internet Caller Identification (ICID) Internet Service Provider (ISP) Line Information Database (LIDB) Numbering Plan Area-Central Office Code (NPA-NXX) Personal Computer (PC) Personal Identification Number (PIN) Point-to-Point Protocol (PPP) Public Switched Telephone Network (PSTN) Real Time Database (RTDB) Registration Server (RS) Service Control Point (SCP) Service Switching Point (SSP) Session Initiation Protocol (SIP) Signaling System 7 (SS7) Signaling Transfer Point (STP) Terminating Attempt Trigger (TAT) Transactional Capabilities Application Part (TCAP) Transmission Control Protocol/Internet Protocol (TCP/IP) User Agent Server (UAS) Wide Area Network (WAN)
3. Description of Background Information
Various attempts have been made at providing Internet caller identification (ICID) services. Typically, a subscriber of Internet caller ID receives the telephone number and name (if available) of a calling party, while the subscriber is on an active Internet session. The caller ID information is provided in a pop-up window on the subscriber's display while the subscriber is actively connected to the Internet. Further, various disposition options are presented to the subscriber which, upon selection, determine the handling of the incoming call.
With such systems, it would be desirable to have an audible alert associated with the calling party. Further, users would appreciate being able to configure a particular sound file to be played according to the incoming telephone number of the calling party.
One attempt at solving this problem was presented by Caller EyeDee by dazil Internet Services. Caller EyeDee appears to permit configured ring sounds (i.e., .wav files) for each individual caller, e.g., “It's Dave Calling”. However, Caller EyeDee apparently does not function while the called party is connected to the Internet via a dial-up connection using a modem because, for instance, Caller EyeDee does not send caller identification information via TCP/IP. Essentially, Caller EyeDee has moved the caller ID functionality from customer premises equipment (CPE) to a personal computer. Additionally, Caller EyeDee apparently requires specialized hardware in the form of a modem that supports Caller ID. Thus, Caller EyeDee is not an effective solution.
The present invention overcomes the problems associated with the prior art. | {
"pile_set_name": "USPTO Backgrounds"
} |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.