An overflow liquid pipe is disposed in such a manner as to pass a liquid which has overflowed from a first container flowing to a second container. The overflow liquid pipe is provided with a pressurizing pipe. A liquid removing unit pressurizes the interior of the overflow liquid pipe through the pressurizing pipe to remove liquid from the overflow liquid pipe.

1. Field of the Invention
The present invention relates to an image forming apparatus, for example, of an ink jet system, and a liquid supply apparatus having a reservoir tank to accommodate an ink liquid supplied from an ink tank, and provided with a countermeasure to remove the ink liquid remaining in a pipe to feed the ink liquid which has overflowed the reservoir tank to an overflow tank.
2. Description of the Related Art
An image forming apparatus of an ink jet system has an ink tank which accommodates an ink liquid. The ink liquid accommodated in the ink tank is supplied to an ink distribution unit through a reservoir tank. The ink liquid supplied to the ink distribution unit is supplied to a plurality of ink heads. The plurality of ink heads spout the ink liquids. An image forming medium such as a recording sheet is conveyed to a position facing the plurality of ink heads at a predetermined speed. Therefore, when the respective ink liquids spouted from the plurality of ink heads are shot on the image forming medium, an image is formed on the image forming medium.
In the image forming apparatus, for example, the ink liquid sometimes overflows the reservoir tank. In the image forming apparatus, a countermeasure for coping with an unusual operation that the ink liquid overflows the reservoir tank is taken. In one example of the countermeasure, an overflow liquid pipe is connected between the reservoir tank and an overflow tank, and the ink liquid which has overflowed the reservoir tank is fed to the overflow tank through the overflow liquid pipe.
At a usual time, when a liquid level height of the ink liquid in the reservoir tank is in the vicinity of an inflow port of the overflow liquid pipe, the ink liquid adheres or gets detached with respect to the inflow port of the overflow liquid pipe. When the ink liquid adheres or gets detached with respect to the inflow port of the overflow liquid pipe, a film of the ink liquid is formed on the inflow port by surface tension or the like. In a worst case, the film of the ink liquid formed on the inflow port sometimes solidifies.
The liquid level height of the ink liquid in the reservoir tank moves upwards or downwards because of a balance between a supply amount of the ink liquid from the ink tank and a supply amount of the ink liquid into the plurality of ink heads. When the liquid level height of the ink liquid moves upwards or downwards, the inflow port of the overflow liquid pipe is sometimes immersed in the ink liquid. In this state, the ink liquid sometimes enters the overflow liquid pipe, and remains as such in the overflow liquid pipe.
In Jpn. Pat. Appln. KOKAI Publication No. 2000-309109, a technique has been described in which a main discharge pipe is opened to the atmosphere to thereby return the ink liquid which has gotten into the discharge pipe to a sub-tank.


A broad-band millimeter wave imaging system with improved thermal resolution as compared to prior art devices. The system is useful for producing images of metal and non-metal objects such as guns, knives and explosives hidden under clothing. A cylindrical antenna focuses millimeter wave radiation from a substantially one dimensional section of a target region onto a linear array of radiation collectors. Radiation collected at each collector is amplified to produce a set of amplified millimeter wave signals and the amplified signals pass through focusing delay lines to a millimeter wave lens. Millimeter wave signals are collected at the output of the lens and the collected signals are monitored by an array of detectors. The combined effects of the delay lines and the lens produce a focus of the amplified millimeter wave radiation emitted and reflected from the one dimensional section of the target region. The array of millimeter wave detectors at the focus of the lens produces a one dimensional image of the one dimensional section of the target region. The antenna is scanned to produce a two dimensional image of the complete target region. The two dimensional image is displayed on a monitor screen. A full two-dimensional image of a human subject located at a stand-off distance of several meters (e.g., 7 meters) from the imager is acquired in few seconds time frame.

Imaging systems operating at millimeter wavelengths (1 cm to 1 mm; 30 GHz to 300 GHz) are well known. These systems can be important because light at these wavelengths is not completely attenuated by substantial distances of fog or smoke, as is visible light. Light at millimeter wavelengths will also penetrate clothing and significant thickness of materials such as dry wood and wallboard. These millimeter wave imaging systems have therefore been proposed for aircraft to improve visibility through fog and for security applications for detection of hidden weapons and the like. Such systems are described in U.S. Pat. Nos. 5,121,124 and 5,365,237 that are assigned to Applicant's employer. The systems described in those patents utilize antennas in which the direction of collected millimeter wave radiation is a function of frequency. This type of antenna is referred to as a "frequency scanned" antenna. The collected millimeter wave light is analyzed in a spectrum analyzer to produce a one-dimensional image. In the systems described in the '124 patent the antenna signal is used to modulate an acousto-optic device (a Bragg cell) that in turn modulates a laser beam to produce a spectral image. In the systems described in the '237 patent an electro-optic module is modulated by the antenna signal and the electro-optic module in turn modulates the laser beam to impose the millimeter wave spectral information on a laser beam that then is separated into spectral components by an etalon to produce an image.
A need exists for a relatively low-cost millimeter wave imaging system with improved thermal resolution.

Multi-channel millimeter wave imaging system


A computer architecture supports reasoning tasks involving information represented in graphical form. The architecture supports the creation, storing, display, and editing of a partially ordered set of nodes representing the steps in a reasoning process, as well as representations of information associated with the nodes. Modifications are constrained by rules that support the creation of valid reasoning. In particular, special rules of inheritance place constraints upon what information is available for display and modification at any given point in the reasoning process. The present architecture supports reasoning about any type of graphical representation and about multiple representations within a single reasoning process. In addition, the present architecture supports extensible representations, i.e., representations that may be edited at later points in a proof to extend the range of possible values which may be assigned to their attributes, or to add or delete objects or attributes. The architecture can simultaneously support and integrate the structured reasoning involving both sentential and graphical representations of information. The techniques provided by the invention have application to a wide variety of engineering and scientific practices by improving the processes through which designs and problem solutions are created, assessed, and communicated. It has particular importance and value for complex collaborative projects.

Modern design and problem solving endeavors have become increasingly large and complex, often involving collaborations of many individuals working toward a common goal. Consequently, computers have been used to assist individuals and teams in performing and managing such projects. There are numerous limitations of these existing applications of computers, however, and various important challenges of design and problem solving endeavors remain unassisted by computers.
Large-scale collaborative projects involve many people reasoning toward the solution of a common problem over an extended period of time. The design and construction of a product, whether an automobile, a building, or a complex hardware or software system, involves a multi-disciplinary team of clients and engineers working toward a common goal. Such distributed reasoning projects frequently yield less than optimal results, or even flounder, for lack of techniques for structuring and recording the complex rationales that drive the evolution of the design over the course of the project. Even when a successful outcome is achieved, later modification of the product is often hampered by the absence of an easily understood record of these rationales.
Most reasoning and design problems require the marshaling, manipulation and communication of information represented in a wide variety of formats. For example, in addition to circuit diagrams an engineering team may use state machine diagrams, timing diagrams and logic ladder diagrams, together with algebraic or natural language specifications of the desired input/output behavior, in order to produce a design that meets the client's needs. Until recently, theoretical accounts of reasoning have limited themselves to homogeneous linguistic reasoning, that is, reasoning in which all information is represented in the form of sentences of some language, either natural or formal. This limitation presents a major obstacle to the application of insights about the structure of reasoning to real-world, collaborative problem solving.
Graphical editing programs, such as computer aided design (CAD) and computer aided architectural design (CAAD) programs, permit the creation and modification of graphical representations such as mechanical drawings, floor plans, schematics, and the like. Typically, a graphical editing program maintains, at any given time, a single internal graphical data structure that is successively modified during the course of editing. Some graphical editing programs temporarily store a small number of prior modifications to the current representation. If a mistake is made during a current editing session, an "undo" feature can be used to retract the most recent modification and revert to an earlier version of the representation. These prior modifications, however, are lost when the program closes the representation file, and are not, therefore, part of the stored graphical data structure itself. It should also be noted that this "undo" feature only allows reverting backward in time through a linear historical sequence of edits. Moreover, if a large project involves several distinct but related graphical representations, such as distinct versions of the same drawing, these programs store them as separate, unrelated files.
Version control systems (VCSs) have been developed to maintain and navigate through distinct versions of files. These files include, for example, the source code of computer programs as well as files containing other forms of data. The purpose of a version control system is to maintain a historical record of successive versions of a document and to decrease the likelihood of inconsistent changes being made by multiple users. Version control systems generally accomplish this goal by requiring that a file be checked out before a user can change it. When a document is checked out, the user usually receives a modifiable copy of the most recent version of the document. After the user has made changes, the modified version is checked in and becomes the most recent version. The VCS maintains previous versions as well as the new version, and records the historical relationship between them. In some cases, the VCS may allow multiple users to check out and modify a file independently. If the modifications are consistent in the sense that they modify different parts of the file, the system may allow an automatic merge of the two versions that incorporates both sets of changes. In no case, however, does a VCS permit a prior version of a file to be directly altered. Instead, the prior version is always preserved as part of a historical record and any alterations based on the prior version of the file are part of a new file. In addition, a VCS never permits alterations to the relationships between existing files. It only permits the addition of a new version of a file and relates it to the existing version upon which it is based. A VCS is also characterized by the fact that any file that has not been checked out is available for further editing at any point in time. It should also be noted that a VCS separately tracks the histories of different files. The version history of one file, therefore, will normally have a structure unrelated to the version history of another file. Moreover, if the two files represent distinct but related parts of a common project or reasoning task, such relations between files are not represented as part of the version history of each file.
Programs have been developed to assist users in correctly constructing and recording certain reasoning tasks. These programs, however, are typically limited to very rigorous forms of reasoning using very constrained forms of symbolic representation. Current proof software, for example, permits the creation and recording of proofs that preserve the logical structure and dependencies between sentential propositions used in a piece of reasoning. Existing proof software only permits a single, sentential form of representation to be associated with each step of the proof structure. In general, these sentential forms of representation are sentences drawn from one of the formal, symbolic languages developed in mathematical logic (e.g. "propositional logic," "first-order logic," "second-order logic," "predicate calculus," and "functional calculus"). These sentences must conform to exacting syntactical rules. In addition, the relationships between the sentences in the proof structure must conform to rigorous logical rules. Consequently, these programs are limited to assisting in only the most rigorous problem solving tasks that can be unambiguously and completely represented in a formal symbolic language. In short, they are not useful for the vast majority of problem solving tasks.
Hyperproof, a proof software program designed for teaching rigorous deductive reasoning, supports reasoning about a single, highly constrained "blocks world" graphical representation, i.e. a graphical representation of a grid upon which may be placed one of a few types of predefined geometrical objects. Hyperproof also constrains the editing of any blocks world diagram to edits that restrict predefined attributes of the blocks to specific values. In order to make tractable the problem of supporting rigorous reasoning about a graphical representation, Hyperproof is limited to providing support for a simple and highly constrained graphical representation of a blocks world which cannot be extended in any way through the course of the reasoning process. It does not provide support for general purpose reasoning tasks because it does not support reasoning involving multiple graphical representations, arbitrary types of graphical representations, or graphical representations that can be extended throughout the course of the reasoning process. Consequently, the program has extremely limited practical utility outside the context of teaching deductive reasoning.

Computational architecture for reasoning involving extensible graphical representations

The Board of Trustees of the Leland Stanford Junior University


A printed circuit board includes a sending element, a plurality of receiving elements, and a control unit. The sending element is configured to generate a sending signal. The receiving elements are configured to receive a control signal respectively. The control unit is coupled to the sending element through a first wire and to the receiving elements through a plurality of second wires. The control unit is provided with a comparison table that stores related information of the second wires. When receiving the sending signal, the control unit generates the control signals according the related information of the second wires. At least one of the control signals is transmitted to the corresponding receiving element, and the rest of the control signals are delayed for a preset time and then transmitted to the rest of the receiving elements.

1. Technical Field
The disclosure relates to a printed circuit board (PCB), and more particularly to a PCB and a signal timing control method thereof.
2. Related Art
During the manufacturing of a printed circuit board (PCB), a circuit layout is usually implemented first to generate an electronic file of a layout diagram. In other words, a layout engineer places electronic elements in preset positions on the PCB, and connects the electronic elements to each other via wires, so as to accomplish the design of the layout diagram. Then, gerber out is performed according to the electronic file of the layout diagram, so as to generate a mask pattern. At last, a PCB manufacturer manufactures the PCB by using the mask pattern.
FIG. 1 illustrates a schematic partial diagram of a common PCB. To synchronize the signal timing so that the time of sending a signal from an element 111 to an element 112 is the same as the time of sending a signal from the element 111 to an element 113, the layout engineer may design the wire between the element 111 and the element 112 and the wire between the element 111 and the element 113 to have the same length. However, it is impossible that the distance between the elements 111 and 112 is the same as that between the elements 111 and 113 on the layout of the PCB 100. The layout engineer may design a longer wire 121 (the wire between the elements 111 and 112) to be straight, and design a shorter wire 122 (the wire between the element 111 and the element 113) to be S shaped, so that the wire 121 and the wire 122 have the same length, thereby synchronize the signal timing.
However, the layout mode of setting the wires to have the same length increases the complexity of the layout design, and the time and efficiency of the layout, and also wastes the utilizable space of the PCB. Therefore, it is necessary to develop the PCB having the signal timing synchronization.

Printed circuit board and signal timing control method thereof

INVENTEC (PUDONG) TECHNOLOGY CORPORATION


According to a nonvolatile memory device having a multi gate structure and a method for forming the same of the present invention, a gate electrode is formed using a damascene process. Therefore, a charge storage layer, a tunneling insulating layer, a blocking insulating layer and a gate electrode layer are not attacked from etching in a process for forming the gate electrode, thereby forming a nonvolatile memory device having good reliability.

The present invention relates to memory devices and methods for forming the same, and more specifically to non-volatile memory devices and methods for forming the same.
The flash memory device is an electrically programmable non-volatile memory device capable of programming in units of pages or multi-bits and erasing in units of blocks or sectors, thereby having excellent characteristics in respect of speed. The flash memory may be used in various devices such as a digital cellular phone, a digital camera, a LAN-switch, a PC card of a notebook computer, a digital set-top box, a built-in controller, etc.
As well known, the flash memory device comprises a source/drain, a tunneling oxide layer, a floating gate, a block insulating layer and a control gate. When a proper bias voltage is applied to the control gate, the source/drain and the substrate, the floating gate is charged or discharged to program or erase to have two different threshold voltages, corresponding to two logic levels.
Also, the semiconductor device should have been highly integrated so as to maintain high performance, high speed, low power dissipation and low production cost. Programming or erasing operation of the flash memory device is performed by injecting charge into the floating gate or rejecting charge therefrom through a tunneling insulating layer. The floating gate can be charged or discharged using Fouler-Nordheim tunneling (F-N tunneling) or channel-hot-carrier injection. In F-N tunneling, a large voltage is applied between the control gate and the substrate resulting in charge accumulating in the floating gate. If the tunneling insulating layer is too thin, charge tunnels the thin tunneling insulating layer at below the programming voltage or even without an external bias voltage. Accordingly, such restriction to the thickness of the tunnel oxide layer serves as an obstacle to achieve a high integration density.
Recently, there has been provided a flash memory device having a multi-gate structure where a plurality of channels are formed, for example, a double gate structure and a triple gate structure.
A flash memory device of multi-gate structure using a silicon fin and a method of forming the same are disclosed in Korea Patent No. 10-0420070. The flash memory device is schematically illustrated in FIGS. 1A and 1B. Reference number 2b in FIGS. 1A and 1B indicates a bulk silicon substrate, reference number 4 indicates a fin active region, reference number 6 indicates a first oxide layer, reference number 10 indicates a second oxide layer, reference number 12 indicates a tunneling oxide layer, reference number 16 indicates a control electrode, reference number 32 indicates a storage electrode, and reference number 34 indicates an oxide layer between electrodes.
However, according to the Korea Patent No. 10-0420070, when the control electrode 16 is defined using photolithography, the fin active region 4 and the tunneling oxide layer 12 can be attacked. If the tunneling oxide layer 12 is attacked deeply, a data retention characteristic of the flash memory device is degraded and the device reliability can not be ensured.
In addition, neighboring control electrodes can be electrically connected, since the control gate is formed crossing over a fin active region 4 having a protruding structure. Accordingly, when over-etching is performed to prevent electrical connection between neighboring control electrodes, sidewalls of silicon fins used as a channel region can be attacked by the etching.

Method for forming non-volatile memory devices


An uncoordinated frequency hopping cellular system includes a mobile unit and a number of base stations. The mobile unit determines information pertaining to a set of base stations that are within a geographical region defined by a location of the mobile unit, and supplies, to at least one of the base stations in the set, the information pertaining to at least one other base station in the set. The information may include address information corresponding to the set of base stations, and may include clock offset information representing a difference between a clock value associated with said at least one of the base stations and a clock value associated with at least one of the other base stations in the set. As different mobile units supply information to the base station, the base station accumulates information about other base stations in the system. The base station supplies this accumulated information to mobile units, so that they may readily have information (e.g., address and/or synchronization information) for more readily establishing communication with base stations that they have not yet encountered.

The invention relates to frequency hopping (FH) radio systems. In particular, it relates to FH radio systems applied in a multi-cell or cellular application comprising fixed base stations and moving portables that while moving, connect from one base station to the other. The invention enables handovers to take place between FH base stations even if the base stations are by no means coordinated.
Since the widespread use of mobile telephony, cellular systems are well known and have reached a high level of maturity. Cellular systems typically comprise a mobile network with a number of base stations located at strategic positions, each base station covering a restricted area called a cell. Because adjacent cells partly overlap, a portable device can move from one cell to the other without losing contact with the mobile network. As the portable moves during a call, the connection is handed off from one base station to another, depending on the relative location of the portable with respect to the base stations.
To support the access to the network and the handover function, the base station typically transmits a predefined (known) radio signal, the so-called control channel or beacon. The control channel reveals the presence of the base station to the portable. Based on the signal strength of the control channel received in the portable, a decision can be made regarding which base station the portable should connect to before or during a call.
Control channels are fixed channels that can easily be found by the portables. They either use a dedicated frequency and/or time slot in Frequency Division Multiple Access (FDMA)- /Time Division Multiple Access (TDMA)-based systems, or a fixed spreading code in direct-sequence Code Division Multiple Access (CDMA)-based systems. In all cases, the carrier frequency on which the control channel is located is fixed, although it can differ per base station. All the portable has to do is to tune to the proper carrier frequency and scan the signals until a decodeable signal is found.
In systems based on frequency-hop CDMA, the situation is completely different. In these systems, the carrier frequency changes periodically according to a pseudo-random hop sequence. Therefore, it is difficult to build cellular systems with a FH system because FH control channels are difficult for the portable to find, especially when the portable has no knowledge of the hop timing and the hop sequence. In the past, FH has been applied in digital cellular systems like GSM in order to increase capacity through interference diversity; however, in these systems, it is only the traffic channels that hop, and never the control channels.
The search effort of a portable in a FH cellular system can be reduced considerably if the hopping between the base stations is coordinated. In this case, once the portable has synchronized to one base station, little effort is required to lock to other, nearby base stations, provided that their FH transmissions are coordinated with the current base station. Thus, the search effort in coordinated systems is only expended the first time the portable enters the mobile network, such as at power up when turning on the portable.
However, when the radio interface uses certain frequency bands, regulations and rules set by regulatory bodies, like the Federal Communications Commission (FCC) in the U.S. or the European Telecommunications Standard Institute (ETSI) in Europe, prohibit the coordination of base stations. An example is the unlicenced Industrial/Medical/Scientific (ISM) band at 2.4 GHz. To use this band, the radio system must spread its signals either by direct-sequence (DS) spreading, or by frequency-hop spreading. As was described above, cellular systems based on DS spreading are attractive to use because fixed carrier frequencies can be used to support the control channels. However, FH spreading is more robust in environments with unknown jammers and results in cheaper transceiver implementations. Unfortunately, the set of rules governing the ISM band do not permit the coordination of FH base stations. This hinders the deployment in this band of multi-cell and cellular FH systems that support, for example, handovers.
Even if a radio band is used in which regulations allow coordination of base stations, for low cost solutions coordination is undesirable. Base stations being used as access pints for wireless access to an existing wired network like PSTN, Ethernet, or any other conventional LAN, cannot rely on coordination and synchronization signals on the wireline. In such a case, a dedicated network would be required to deal with the mobility functions required by the access points. This is not an attractive solution. In the preferred case, an access point can be plugged in to a conventional wired backbone without requirements for coordination and synchronization signals.
It is therefore desirable to provide a system and method that applies frequency hopping in a communications system that performs handovers between uncoordinated base stations.
It is therefore an object of the invention to provide an uncoordinated frequency hopping cellular system, a mobile unit for use in an uncoordinated frequency hopping cellular system, a base station for use in an uncoordinated frequency hopping cellular system, and methods for operating the mobile unit, the base station and the system.
In accordance with one aspect of the invention, the mobile unit determines information pertaining to a set of base stations that are within a geographical region defined by a location of the mobile unit. The mobile unit then supplies, to at least one of the base stations in the set, the information pertaining to at least one other base station in the set. In each base station, this information may be received and accumulated.
In another aspect of the invention, the information may include address information corresponding to the set of base stations.
In yet another aspect of the invention, the information may include clock offset information representing a difference between a clock value associated with said at least one of the base stations and a clock value associated with at least one of the other base stations in the set.
In still another aspect of the invention, mobile unit receives additional information from said at least one of the base stations, wherein the additional information includes information pertaining to at least one base station that is not in the set of base stations. For example, the addition information may include synchronization information pertaining to the at least one base station that is not in the set of base stations. This additional information may then be used to establish communication with said at least one base station that is not in the set of base stations.
The base stations may occasionally received updated information from more recent contact with mobile units. Thus, in yet another aspect of the invention, the base stations may estimate a rate of clock drift between an own clock located within the base station and another clock located within another base station in the system.
In still another aspect of the invention, the base stations may use the estimated rate of clock drift to correct a stored clock offset value representing a difference between a clock value associated with the own clock and a clock value associated with said another clock located within said another base station in the system.
In yet another aspect of the invention, a mobile unit for use in an uncoordinated frequency hopping cellular system communicates with a first base station in the uncoordinated frequency hopping cellular system; and receives information from the first base station, wherein the information includes addresses and clock offset values of neighboring base stations in the uncoordinated frequency hopping cellular system.
In still another aspect of the invention, each of the clock offset values represents a difference between a clock value associated with the first base station and a clock value associated with a corresponding one of the neighboring base stations.
In yet another aspect of the invention, the mobile unit uses the information from the first base station to establish communication with at least one of the neighboring base stations.
In still another aspect of the invention, the mobile unit supplies additional information to the first base station, wherein the additional information includes address and clock offset information pertaining to another base station in the uncoordinated frequency hopping cellular system.
In yet another aspect of the invention, the mobile unit performs an inquiry procedure that yields the additional information.

Uncoordinated frequency hopping cellular system


Methods and apparatus are provided for automatically and autonomously forming a wireless personal area network (WPAN) from an array of intercommunicating personal area network (PAN) devices. The devices comprise first communicators associated with primary functions of the devices and second communicators coupled to the first communicators for determining a subset of the devices meeting predetermined association criteria, from which subset the first communicators form the WPAN. In a preferred embodiment, the second communicators include range measuring transceivers and processors coupled to the transceivers that cooperate to determine range and relative motion of elements within communication range of the first communicators for comparison to range and relative motion association criteria stored in one or more of the devices. Memory is desirably included for storing the association criteria. The subset of devices automatically elects a master device that communicates with the other devices of the subset to form the WPAN.

Many modern electronic devices are portable and capable of communicating with each other and various base stations using wireless signaling. Non-limiting examples are 2-way radios, telephones, headsets, bar code scanners, Global Positioning System (GPS) units, Personal Digital Assistants (PDAs), portable computers (PCs), printers, digital cameras, RF identification (RFID) tag readers/writers, chart plotters, and so forth. Sometimes, a number of these various elements may be carried by or associated with a single user or function and it is desired to mutually associate them electronically to form a wireless personal area network (WPAN). Once associated, the cooperating elements can exchange or share data by communicating directly with each other rather than indirectly via a central hub, and in general, ignore other units that may be within communication range but which are not part of the WPAN. It is known in the prior art to form such WPANs, but the association of the various elements into the WPAN had to be carried out manually. This is done, for example, by entering into each unit the identity of the other elements of the WPAN. Another way is to use a local sub-master unit as a temporary hub. The identities (IDs) of the units intended to make up the WPAN are manually entered or scanned into the sub-master and then the association information downloaded from the sub-master to each of the WPAN elements. While this approach works it suffers from a number of disadvantages among which are: it is time consuming to manually reconfigure and associate the units for a particular WPAN; the WPAN make-up is not easily changed, that is, it is static rather than dynamic; it is more complex and inflexible than is desired; and it may require that the individual elements of the WPAN consume more power.
Accordingly, it is desirable to provide an improved arrangement for forming and using WPANs, especially to provide an arrangement and method capable of forming and reforming WPAN associations automatically. In addition, it is desirable that the arrangement and method be robust and inexpensive relative to the prior art and, insofar as possible, take advantage of existing technology and devices. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.

Self-associating wireless personal area network


Tool holder for cutting bodies (5) may be mounted on a base holder (15) by a fixing device (41), and a cooperating stop extending in a plane in the direction of the tool holder. A positive positional fixing against any movement along the three axes of the spatial coordinate system may be obtained. The planar stop is divided into planar sections (19, 21) by a machined recess (23). The recess (23) forms a seat for housing a projecting matching body (25) on the base holder (15). The walls of the recess (23) form planar support surfaces (31, 33) for the matching body (25), which each define differing planes perpendicular to the stop, to resist displacement and torsional forces resulting from the cutting force into the matching body (25) of the base holder (15).

DE 40 24 096 C2 discloses a tool holder having a cutting tool for metal cutting, a minicutter bar in particular. A cutting insert is braced by a clamping leg resting against it on a flat clamping surface in a recess having cutting insert mounting surfaces of a lengthwise slotted forked holder shaft. In the disclosed solution, the clamping surface of the cutting insert is positioned in parallel with the axis of the holder shaft. The recess in the holder shaft has three cutting insert bearing surfaces, specifically, a bottom surface, a main cutting pressure support surface, and a back pressure support surface which include angles smaller than 90° both relative to each other and to a side surface and a frontal surface as the only open side surfaces.
In use of such tool holders, it is extremely important for cutting of work pieces with respect to the accuracy to be achieved in the machining process and especially also to the quality of the surfaces machined for it to be possible to mount the tool holder with its bearing surface absolutely rigid and to secure on the base holder by means of the fastening device. In other words, it must be made certain that force components acting between tool holder and base holder as shearing forces or forces of torque, ones which try to twist the tool holder on the base holder, will be introduced safely, that is, without impairing the secure seating, into the base holder by way of the bearing surface.
DE 195 17 365A1 discloses a tool holder for machining by turning, comprising a base recess as tool holder which may be mounted with its tool axis oriented perpendicular to the axis of rotation on a tool carrier as base holder. A cutter holder is mounted to be replaceable on the base recess, and a cutting plate is mounted on the cutter holder so as to be replaceable. The base recess itself has a bearing surface as bearing component extending transversely to the tool axis. The cutter holder has a mounting surface and is detachably mountable with this surface on the bearing surface on the base recess. The cutter holder is immobilized against all relative movements of the mounting surface relative to the bearing surface by fitting elements, the cutter holder having at least one cutting insert seat.
Since, in this disclosed solution, the bearing component is not configured to be planar, but rather is designed with a gear cutting geometry, and the mating teeth of tool holder and base holder have frontal surfaces which are diametrically opposite each other, despite the fitting elements referred to above, especially ones in the form of set screws, tilting processes occur. The tilting results in an adverse effect on the accuracy of machining with the indexable inserts seated in the tool holder, since the latter also are also tilted and accordingly displaced in their machining plane. In addition, because of the gear cutting geometries, the disclosed solution results in increased production costs, in particular if the respective toothing is to be produced as high-precision toothing.
U.S. Pat. No. 5,688,080 discloses a generic tool holder for cutting elements, indexable inserts in particular. The tool holder may be mounted on a base holder by a fastening device with three fastening screws and a bearing component operating in conjunction with this base holder. A bearing component extends in a planar configuration in the direction of the tool holder. The cutting forces generated by the cutting element are introduced into the base holder by the bearing component, such bearing component being of planar configuration and being divided by a recess which is introduced into planar components. Between the planar components, the recess forms a seat to receive a projecting fitting element of the base holder. The walls of the recess for the fitting element form support surfaces which define, in relation to each other, different planes which, planar in configuration, extend transversely to the bearing component to introduce into the fitting element of the base holder both the shearing forces resulting from the cutting force and the torsional forces. In the solution, as disclosed, the recess is, with the exception of an area of opening on an edge in the tool holder, delimited on all sides by three walls. The walls define planes, all of which extend perpendicularly to the plane of the planar components. In particular, with respect to such planar components during fastening of the tool holder to the base holder, over determinations occur which are offset by a wedge which may be adjusted by means of a twin screw inside a recess in the fitting element designed to be longitudinally displaceable. A twin screw effects compensation for play between tool holder and base holder. If the bearing play in question is offset in the disclosed solution by the wedge, changes in position in the active cutting area of the cutting element result, preventing high-precision machining from being carried out with the disclosed solution. This disclosed solution is not cost-effect in production in view of the great variety of components.

Hartmetall-Werkzeugfabrik Paul Horn GmbH


A radio frequency driving circuit and a radio frequency signal switching method that are capable of easily controlling a radio frequency signal in a radio frequency plasma display panel. In the method, a turning-on signal is applied before the radio frequency signal is completely erased by applying a turning-off signal to a radio frequency generator. Accordingly, a rising time of the radio frequency signal is reduced, so that the radio frequency signal can be switched to be suitable for the PDP driving.

1. Field of the Invention
This invention relates to a plasma display panel (PDP), and more particularly to a radio frequency driving circuit and a switching method thereof that are capable of switching a radio frequency signal to be adaptive for a radio frequency PDP driving.
2. Description of the Related Art
Recently, a plasma display panel (PDP) feasible to the fabrication of large-scale panel has been available for a flat panel display device. The PDP includes discharge cells corresponding to color pixels of matrix type and controls a discharge interval of each discharge cell to display a picture. More specifically, after the PDP selected discharge cells to be displayed by an address discharge, it allows a discharge to be maintained in a desired discharge interval at the selected discharge cells. Thus, in the discharge cells, a vacuum ultraviolet ray generated during the sustaining discharge radiates a fluorescent material to emit a visible light. In this case, the PDP controls a discharge-sustaining interval, that is, a sustaining discharge frequency of the discharge cells to implement a gray scale required for an image display. As a result, the sustaining discharge frequency becomes an important factor for determining the brightness and a discharge efficiency of the PDP. For the purpose of performing such a sustaining discharge, a sustaining pulse having a frequency of 200 to 300 kHz and a width of about 10 to 20 xcexcs has been used in the prior art. However, the sustaining discharge is generated only once at a extremely short instant per the sustaining pulse by responding to the sustaining pulse; while it is wasted for a step of forming a wall charge and a step of preparing the next sustaining discharge at the remaining major time. For this reason, the conventional three-electrode, face-discharge, and AC PDP has a problem in that, since a real discharge interval is very short in comparison to the entire discharge interval, the brightness and the discharge efficiency become low.
In order to solve such a problem of low brightness and low discharge efficiency, we has suggested a method of utilizing a radio frequency discharge employing a radio frequency signal of hundreds of MHz as a display discharge. In the case of the radio frequency discharge, electrons perform an oscillating motion by the radio frequency signal to sustain the display discharge in a time interval when the radio frequency signal is being applied. More specifically, when a radio frequency signal with a continuously alternating polarity is applied to any one of the two opposite electrodes, electrons within the discharge space are moved toward one electrode or the other electrode depending on the polarity of the voltage signal. If the polarity of a radio frequency voltage signal having been applied to the electrode before the electrons arrive at the electrode is changed when electrons are moved into any one electrode, then the electrons has a gradually decelerated movement speed in such a manner to allow their movement direction to be changed toward the opposite electrode. The polarity of the radio frequency voltage signal having been applied to the electrode before the electrons within the discharge space arrive at the electrode is changed as described, so that the electrons make an oscillating motion between the two electrodes. Accordingly, when the radio frequency voltage signal is being applied, the ionization, the excitation and the transition of gas particles are continuously generated without extinction of electrons. The display discharge is sustained during most discharge time, so that the brightness and the discharge efficiency of the PDP can be improved. Such a radio frequency discharge has the same physical characteristic as a positive column in a glow discharge structure.
FIG. 1 is a perspective view showing the structure of a discharge cell of the above-mentioned radio frequency PDP employing a radio frequency discharge. In FIG. 1, the discharge cell 26 includes radio frequency electrodes 12 provided on an upper substrate 10, data electrodes 16 and scanning electrodes 20 provided on a lower substrate 14 in such a manner to be perpendicular to each other, and barrier ribs 22 provided between the upper substrate 10 and the lower substrate 14. The radio frequency electrodes 12 apply a radio frequency signal. The data electrodes 16 apply a data pulse for selecting cells to be displayed. The scanning electrodes 20 are provided in opposition to the radio frequency electrodes 12 in such a manner to be used as opposite electrodes of the radio frequency electrodes 12. Between the data electrodes 16 and the scanning electrodes 20 is provided a dielectric layer 18 for the charge accumulation and the isolation. The barrier ribs 22 shut off an optical interference between the cells. In this case, the barrier ribs 22 are formed into a lattice structure closed on every side for each discharge cell so as to isolate the discharge space. This is because it is difficult to isolate a plasma for each cell unlike the existent face-discharge due to the opposite discharge generated between the radio frequency electrodes 12 and the scanning electrodes 20. Also, the barrier ribs 22 have a more enlarged height than the conventional barrier ribs for the sake of providing a smooth radio frequency discharge between the scanning electrodes 20 and the radio frequency electrodes 12. A fluorescent material 24 is coated on the surface of the barrier rib 22 to emit a visible light with an inherent color by a vacuum ultraviolet ray generated during the radio frequency discharge. The discharge space defined by the upper substrate 10, the lower substrate 14 and the barrier ribs 22 is filled with a discharge gas.
As shown in FIG. 2, the discharge cells 26 having the configuration as described above are positioned at each intersection among data electrode lines X1 to Xm, scanning electrode lines Y1 to Yn and radio frequency electrode lines RF. In FIG. 2, the data electrode lines X1 to Xm consist of the data electrodes 16 of the discharge cells 26. The scanning electrode lines Y1 to Yn consist of the scanning electrodes 20, and the radio frequency electrode lines RF consist of radio frequency electrodes 12.
The discharge cell 26 of FIG. 1 is driven a driving waveform as shown in FIG. 3. A radio frequency pulse RFP more than tens of MHz is continuously applied to the radio frequency electrode 12. At an A region in which a data pulse DP is applied to the address electrode 16 and a scanning pulse SP is applied to the scanning electrode 20, an address discharge is generated by the voltage difference Vd+Va. By this address discharge, charged particles are produced at the discharge space. These charged particles make a radio frequency discharge by a radio frequency pulse RFP applied to the radio frequency electrode 12 and a center voltage Vc of a radio frequency voltage applied constantly to the scanning electrode 20. In this case, an ultraviolet ray generated by the radio frequency discharge radiates the fluorescent material 24 to emit a visible light. At a C region in which an erasing pulse EP is applied to the scanning electrode 20, the charged particles are vanished by an erasure voltage Ve to stop the radio frequency discharge.
As described above, the conventional radio frequency PDP applies the radio frequency signal continuously to thereby initiate the radio frequency discharge by the charged particles produced by the address discharge and the radio frequency signal and stop the radio frequency discharge by the erasure pulse EP. The gray scale is implemented by differently setting a time at which the erasure pulse EP is applied to control the radio frequency discharge interval, that is, the discharge-sustaining interval. If the radio frequency signal is continuously applied in the remaining interval except for the radio frequency discharge interval, however, then problems such as signal interference, noise and miss-discharge, etc. may be generated. In order to prevent these problems, it is necessary to switch the radio frequency signal to provide it only in the radio frequency discharge interval. However, it is difficult to switch the radio frequency signal requiring more than hundreds of volt (V), for the sake of providing the radio frequency discharge, at a rapid time rate such as the radio frequency discharge interval.
More specifically, a radio frequency circuit of the PDP for switching a radio frequency signal can be configured as shown in FIG. 4. Referring to FIG. 4, the radio frequency circuit includes a radio frequency generator 30 for generating a radio frequency signal, an amplifier 34 for amplifying the radio frequency signal from the radio frequency generator 30, and an impedance matcher 37 connected between the amplifier 34 and a panel 38. The radio frequency generator 30 generates a low level of radio frequency pulse and outputs it to the amplifying unit 35. The amplifying unit 35 consists of the amplifier 34 and a peak detector 36. The amplifying unit 35 amplifies the radio frequency pulse from the radio frequency generator 30 into a power required for the radio frequency discharge and output it. The peak detector 36 detects a peak-to-peak value PPrf from the radio frequency pulse from the amplifier 34 and feeds it back into the amplifier 34 thereby allowing the amplifier 34 to amplify and output the radio frequency pulse into a certain power. The impedance matcher 37 matches an impedance at the output terminal of the amplifying unit 35 with an impedance of the panel 38, thereby applying a maximum power of radio frequency signal to the radio frequency electrode 12. Generally, an incident wave and a reflective wave co-exist in the radio frequency circuit, and a power superposed with the incident wave and the reflective wave is applied to the radio frequency electrode 12 of the panel 38. Thus, to apply a maximum power by the impedance matching means to allow an incident wave to be applied to the radio frequency electrode 12 as it is by a minimization of a reflective wave.
The switch 32 switches the radio frequency signal from the radio frequency generator 30 in accordance with a switching signal SWS, as shown in FIG. 5, inputted via an input line 31. Referring to FIG. 5, the switch 32 is turned off in address intervals (AP1, AP2, AP3, . . . ) of each sub-field (SF1, SF2, SF3, . . . ) at which the input switching signal SWS has a low level to thereby shut off the radio frequency pulse from the radio frequency generator 30. On the other hand, the switch 32 is turned on only in discharge-sustaining intervals (SP1, SP2, SP3, . . . ) of each sub-field (SF1, SF2, SF3, . . . ) at which the input switching signal SWS has a high level to thereby apply the radio frequency pulse from the radio frequency generator 30 to the amplifier 34. In this case, the switch 32 must generate a radio frequency signal in a soft start manner so as to assure a safety of the entire PDP system. This is because of a damage of circuit caused by a rush current when a high voltage of radio frequency signal is rapidly generated. Accordingly, the switch 32 has to slowly increase the radio frequency voltage in a range in which the rush current is minimized. In such a soft start method, however, a time of at least tens of to hundreds of xcexcs is wasted for a rising time until the radio frequency signal arrives at a normal level.
As described above, in the conventional radio frequency signal switching method, a considerably long time is wasted for a rising time when the radio frequency signal is increased into a normal level required for the radio frequency discharge after the generation thereof. Accordingly, the radio frequency discharge interval is relatively shortened to have a bad influence on the guarantee of display time regarded as a most important factor in the PDP. In other words, the conventional radio frequency signal switching method is not applicable to a PDP required to switch a radio frequency signal within a very short time for the purpose of an implementation of gray scale as it is.
Accordingly, it is an object of the present invention to provide a radio frequency driving circuit and a radio frequency signal switching method thereof that is capable of sufficiently assuring a radio frequency discharge interval by switching a radio frequency signal in a rapid time interval suitably for a PDP driving.
A further object of the present invention is to provide a radio frequency driving circuit and a radio frequency signal switching method thereof that is capable of stably driving a PDP employing a radio frequency signal by switching the radio frequency signal to apply the same to a panel only in a display interval.
In order to achieve these and other objects of the invention, a method of switching a radio frequency signal in a plasma display panel according to one aspect of the present invention includes applying a turning-on signal before the radio frequency signal is completely erased by applying a turning-off signal to a radio frequency generator, thereby generating the radio frequency signal.
A driving circuit for a plasma display panel according to another aspect of the present invention includes radio frequency generating means for generating a radio frequency signal; and impedance matching means for matching an impedance of the radio frequency generating means with that of the plasma display panel and varying the matched impedance to switch the radio frequency signal.
A method of switching a radio frequency signal in a plasma display panel employing the radio frequency discharge according to still another aspect of the present invention includes controlling a power level of the radio frequency signal applied to the plasma display panel to switch the radio frequency signal.
A driving circuit for a plasma display panel according to still another aspect of the present invention includes radio frequency generating means for generating a radio frequency signal to apply it to a radio frequency electrode of the plasma display panel; and switching means connected between other electrode of the plasma display panel connected to a ground line of the radio frequency generating means and the ground line to be switched in accordance with said interval of the radio frequency discharge, thereby controlling a power level of the radio frequency signal applied to the radio frequency electrode.
A method of controlling a plasma display panel device according to still another aspect of the present invention wherein an address discharge for selecting cells to be displayed is made by a current voltage applied to crossing electrodes while a sustaining discharge for sustaining said discharge of the selected cells to provide a display is made by a radio frequency voltage, includes turning on or off said radio frequency voltage with a switching pulse to be turned on only in the sustaining-discharge interval; and applying turning-on signal before the radio frequency signal is completely erased by applying a turning-off signal.

Radio frequency driving circuit of plasma display panel and method of switching the same


A dynamically reconfigurable communications system is presented. The communications system comprises a server, including one or more radio head interface modules, a call processing software module, and a radio head unit coupled to the radio head interface module over one or more transport mediums. The one or more radio head interface modules adapted to communicate with the call processing software module, wherein the call processing software performs modulation and demodulation of voice and data streams using one or more air interface protocols. The radio head unit communicates with one or more subscriber units using the one or more air interface protocols. The radio head interface module receives power level adjustment parameters from the call processing software module for one or more logical channels and reconfigures the signal gain of one or more communications channels based on the power level adjustment parameters.

Many changes are taking place in the way wireless communication networks are being deployed. Some of the changes are being driven by the adoption of new mobile communications standards. The introduction of software defined radios to wireless telecommunications has led to the generation of software and hardware solutions to meet the new standards.
A software defined radio (SDR) uses software for the modulation and demodulation of radio signals. The use of reprogrammable software allows key radio parameters, such as frequency and modulation protocols to be modified without the need to alter the underlying hardware of the system. Additionally, SDRs allow a single device to support multiple configurations which previously would have required multiple hardware devices. One example of a software defined radio is the Vanu Software Radio produced by Vanu, Inc. (See U.S. Pat. No. 6,654,428).
Current mobile communication standards introduce physical and logical channels and pose new issues in the transport of information within the communication networks. Some modulation protocols that wireless communication networks operate with includes, but is not limited to, Advanced Mobile Phone System (AMPS), code division multiple access (CDMA), Wide-band CDMA (WCDMA), time division multiple access (TDMA), Global System for Mobile communications (GSM), Cellular Digital Packet Data (CDPD), Enhanced Data rates for GSM Evolution (EDGE), General Packet Radio Service (GPRS), Integrated Digital Enhanced Network (iDEN), and Orthogonal Frequency Division Multiplexing (OFDM).
Purchasing hardware designed to operate with only a single standard results in idle resources at times when network demand for that modulation standard is low. To avoid the expenses associated with operating and maintaining hardware dedicated to each standard, there is a need in the art today for communications network hardware that is modulation standard independent and can be dynamically reconfigured to support modulation standards based on the current demands on the network and operate with multiple standards simultaneously.
Another need generated by the adoption of new mobile communications standards is ability for communications network hardware to dynamically adjust the power levels of radio frequency transmissions in order to maintain acceptable signal quality as required by standards. Signal power level adjustments are required both in order to minimize co-channel interference and to conserve power.
For the reasons stated above, and for other reasons stated below that will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the telecommunications industry for systems and methods for dynamically reconfigurable communication networks which can dynamically adjust communications signal gains.


An object of the invention is to provide an oscillator with a pedestal that facilitates soldering operations and offers a high level of productivity. A surface mount crystal oscillator with a pedestal comprises a crystal oscillator with lead wires led out from a bottom surface of a metallic base thereof; and a pedestal having a substantially rectangular outer shape in plan view, has insertion holes through which the lead wires pass, and is attached to a bottom surface of the crystal oscillator, and has mount terminals to be electrically connected to the lead wires formed on a bottom surface thereof. The configuration is such that the insertion holes are provided in four corner sections of the pedestal, in the four corner sections of the bottom surface of the pedestal where the insertion holes are formed there is provided a recess with an open outer periphery, and the lead wire is connected to a terminal electrode formed inside the recess, using solder.

1. Technical Field
The present invention relates to a surface mount crystal oscillator with a pedestal (hereunder, referred to as "oscillator with a pedestal"), and in particular to an oscillator with a pedestal that enables easy attachment of a pedestal to a crystal oscillator.
2. Background Art
Crystal oscillators that serve as frequency control devices used for mobile communication devices or transmission communication devices, are well known. As one of these crystal oscillators, there has been widely used a lead-type crystal oscillator in which lead wires are perpendicularly implanted in the bottom surface of the oscillator. On the other hand, while surface mounting of electronic components has made progress, there has also been a demand to be able to surface mount a crystal oscillator. Under such a background, there has been proposed a crystal oscillator with a pedestal in which a pedestal is attached on an existing lead-type crystal oscillator thereby enabling surface mounting thereof (refer to Japanese Unexamined Patent Publication No. 2000-286661 (Patent Document 1)).
3. Prior Art
FIG. 6 and FIG. 7 are drawings for describing an oscillator with a pedestal of a conventional example, wherein FIG. 6A is a front view thereof, FIG. 6B is a bottom view thereof, and FIG. 6C is a sectional view thereof taken along the line VI-VI of FIG. 6B. FIG. 7 is an exploded isometric view of a pedestal of the conventional example, wherein FIG. 7A shows an exploded view of a first substrate and FIG. 7B shows an exploded view of a second substrate.
Here, there is described an oscillator with a pedestal disclosed in Japanese Unexamined Patent Publication No. 2006-332932 (Patent Document 2). Although it is described as a crystal resonator with a pedestal in this Patent Document 2, a similar configuration can be applied to a crystal oscillator with a pedestal, and therefore it is described here as a crystal oscillator with a pedestal.
In this crystal oscillator with a pedestal, a pedestal 2 is attached to a crystal oscillator 1 as shown in FIG. 6A to FIG. 6C. The crystal oscillator 1 is configured with a crystal resonator (not shown in the drawing) and an oscillation circuit element (not shown in the drawing) housed (enclosed) inside a metallic base 3, and a metallic cover 4 joined thereon. On an outer bottom surface 3a of the metallic base 3 of the crystal oscillator 1, there are provided stand-offs 5, thereby preventing electrical short circuit between a mounting substrate (not shown in the drawing) and the metallic base 3, when the crystal oscillator 1 is directly mounted on the mounting substrate. On the outer bottom surface 3a of the crystal oscillator 1, there are implanted four lead wires 6 perpendicular to the outer bottom surface 3a. The lead wires 6 are electrically connected to the oscillation circuit element and the like housed in the metallic base 3.
Next, the pedestal 2 comprises a laminated plate comprising a first substrate 7 serving as an upper layer and a second substrate 8 serving as a lower layer. Moreover, the pedestal 2 has insertion holes 9a and 9b in portions thereof corresponding to the lead wires 6. Here, the radius of the insertion hole 9b formed in the second substrate 8 is made greater than the radius of the insertion hole 9a of the first substrate 7 (refer to FIG. 7A and FIG. 7B). Moreover, each of the lead wires 6 passes through each of the insertion holes 9a of the first substrate 7. On the inner side surface of each insertion hole 9a, there is formed a metallic film that serves as a conducting path 10a (refer to FIG. 6C).
On the outer periphery of the insertion hole 9a on the lamination surface of the first substrate 7 that is to have the second substrate 8 laminated thereon, as shown in FIG. 6C, there is formed a terminal electrode 11, and on a bottom surface 8a of the second substrate 8 that serves as the bottom surface of the pedestal 2, there are formed mount terminals 12. The lead wire 6 having passed through the insertion hole 9a is electrically connected to the terminal electrode 11 by means of solder 13. Moreover, the solder 13 also flows into the insertion hole 9a, and consequently the lead wire 6 is electrically and mechanically connected to the conducting path 10a. As a result, the lead wire 6 is electrically connected to the mount terminal 12 via; the terminal electrode 11 and the conducting path 10a, a conducting path 10b formed on a surface 7a of the first substrate 7 facing the crystal oscillator 1, and a conducting path 10c formed on the side surface of the pedestal 2.


A computer system in which the signal parameters of an analog display signal received by a display unit can be determined automatically. A test data having a predetermined format is sent to a display unit. The test data is encoded to enable display unit to measure display signal parameters such as the timing signals (e.g., start position of each horizontal line) accurately. The test data also includes black and white points, which enable the display unit to measure the voltage levels used to represent black and white signals. Display unit can accordingly adjust the manner in which individual points on a display screen are actuated so that the full scale of brightness levels on individual points can be utilized. CRC-based techniques are used to indicate to the display unit the presence of the test data as the same communication path is used to send test data and display data.

1. Field of the Invention
The present invention relates to computer graphics systems, and more specifically to a system and method for automatically determining the signal parameters of an analog display signal received by a display unit of a computer system.
2. Related Art
Display units are often used in computer systems to display images. Typically, an image is sent to a display unit encoded in the form of an analog signal (e.g., RGB signals) and the display unit reproduces the image represented by the analog signal. For a proper reproduction of the image, it may be necessary to determine the signal parameters (explained below) of the analog signal.
In general, signal parameters are the values which enable a display unit to reproduce an image represented by the analog display signal. For example, as is well known in the art, an analog display signal can include several portions, with each portion representing a frame of an image. Each such portion can include several sub-portions, with each sub-portion representing a horizontal line. Several such horizontal lines together constitute a frame.
For an accurate reproduction of an image represented by an analog signal, a display unit may need to accurately determine the instances or points on an analog display signal which correspond to start positions ("horizontal start positions") of these horizontal lines and/or frames. Similarly, a display unit may need to determine other parameters such as vertical start position, height and width of an image for an accurate reproduction. Such parameters, which may be needed for accurate reproduction of an image are termed as display signal parameters in the present application.
Without such an accurate determination of one or more of the above noted parameters, a portion of an image may not be displayed on a screen of a display unit. As an illustration, if a horizontal start position is determined to be at a position later than a correct horizontal start position, some of the left portion of the horizontal line may not be displayed. On the other hand, if horizontal start position is determined to be at a position earlier than a correct horizontal start position, some of the right portion of the horizontal line may not be displayed.
Some prior systems attempt to use only a part of a digital display screen area as a matter of design so that inaccurate determination of a start position described above will not necessarily result in an image portion not being displayed. That is, under this scheme, if a start position is determined to be earlier or later than a correct start position, the sampled image may be displayed on a part of the display screen, which part may not be otherwise used if the start positions were to be correctly sampled. One problem with such a scheme is that the design employed there does not make full use of the display screen area under correct operating circumstances.
In an alternative scheme, a user is provided the option to manually adjust the start positions, height and width. Unfortunately, such manual schemes may be undesirable, particularly in consumer markets where the users may not be willing or sophisticated to use such manual features.
There are other display parameters which may be important for an accurate reproduction of an image represented by an analog display signal. Voltage swing of a digital to analog converter (DAC) is an example of such other display parameters. Voltage swing generally refers to the voltage values between the voltages used to represent maximum and minimum brightness levels of points of an image. DACs are typically situated in a computer system and generate analog display signals based on digital data representation of an image. Display units commonly receive these analog display signals and generate an image based on the received display signal.
The maximum and minimum values are typically defined by industry standards. However, manufacturing imperfections and inadequate testing often result in computer systems which have substantial deviation from the maximum and minimum voltage levels. As an illustration, according to RS-170 and VESA standards known in the art, minimum and maximum brightness levels are to be encoded in 0.0 V and 0.7 V respectively. However, these voltage levels can be in the range of 0.5 V to 1 V in typical implementations found in the market.
One problem with such deviations is that the resulting display quality may be sub-optimal. For example, if a display unit is designed to assume that maximum brightness is represented by 0.7 volts, but if a computer system generates a voltage level of 0.8 for maximum brightness, the graphics system may display all points having a voltage value above 0.7 at a maximum brightness level. Accordingly, highlight contrast is lost. On the other hand, if a computer system generates a voltage of 0.6 V (i.e., less than the correct voltage level) for the full brightness level, the full range of brightness levels possible on the display screen may not be fully utilized. In either case, the display quality is not optimal.
In some display units, a user is provided the ability to manually adjust the brightness level, and the display unit is designed to adjust the assumed voltage swing. However, the manual schemes are generally undesirable as users may not have the sophistication or desire or willingness to recognize the deviations from voltage swing levels. In addition, it may not be easy to perfectly adjust the assumed voltage swing levels manually in the display unit.
Therefore, what is needed is a scheme which enables an accurate and automatic determination of display signal parameters of an analog display signal received by a display unit.

Method and apparatus for automatically determining signal parameters of an analog display signal received by a display unit of a computer system


Embodiments of the invention provide a sealing system configured to provide a sealed boundary between a conditioned and an uncontrolled or separately conditioned environment. In some examples, the sealing system may comprise a door, a conditioning device, and a seal assembly. The door may be moveable between an opened position and a closed position. The seal assembly may be coupled to the door and have an airflow path. When the door is in the closed position, the conditioning device may be configured to direct conditioned air into the airflow path, thereby urging conditioned air through the seal to inhibit undesirable door and/or adjacent surface conditions.

The present disclosure is described in the context of sealing systems and methods. More specifically, the present disclosure relates to a sealing system for a sliding door configured to selectively seal and unseal a conditioned compartment.
Traditionally, sealing systems that are provided for selectively sealing and unsealing conditioned compartments (e.g., walk-in freezers) have some type of door movable between an opened position and a closed position. Given the conditions of the uncontrolled environment surrounding the door (e.g., temperature, humidity, etc.) frost can form and accumulate on an outer surface of the door and the surrounding surfaces, such as the floor. In some instances, this frost buildup can prevent the door from functioning properly or have other undesirable impacts on the working conditions near the door threshold.

Sealing system for a conditioned door threshold


A UV sensor (1) includes a container (5) in which the upper end opening of a metal side tube (2) is sealed with a front plate (3) composed of borosilicate glass as an incident light window and the lower end opening is sealed with a base plate (4). The front plate (3) serving as an incident light window constitutes part of the wall of container (5) by sealing the upper end opening of the metal side tube (2). A pin-type photodiode (6) is disposed inside the container (5). The pin-type photodiode (6) comprises a photoabsorption layer (9) formed from InxGa(1−x)N (0<x<1) between an n-type contact layer (8) and a p-type contact layer (10).

1. Field of the Invention
The present invention relates to a UV sensor equipped with a pin-type photodiode.
2. Related Background Art
Devices combining an optical filter having a property of transmitting only the light with a specific wavelength and a photodiode using semiconductor Si have been known as UV sensors for monitoring optical intensity of UV radiation with a wavelength close to 365 nm. Further, a pin-type nitride semiconductor photoreceiving element comprising a photoreceiving layer composed of an i-type gallium nitride compound semiconductor between an n-type layer and a p-type layer composed of gallium nitride compound semiconductors have been known as a device for selectively detecting light within a specific wavelength range (Japanese Patent Application Laid-open No. 2002-83996).


Finite element analysis or thermocouple probes are used to determine the state of cure for each zone of a non-uniform, thick rubber article, such as a large tire or a tread for a tire. From this knowledge of those cure-limiting zones, heat transfer elements are added to the mold to enhance the transfer of heat into these cure-limiting zones and to provide a more optimum cure. The use of heat transfer pins and/or mini-sipes are an efficient and practical means of reducing total cure time in the press and optimizing cure state without substantially affecting the performance of the article such as the tire. Reductions in cure time of 10% or more are demonstrated.

1. Field of the Invention
The present invention is in the field of curing thick, non-uniform rubber articles, and more particularly in the field of curing tires such as truck tires.
2. Description of the Related Art
Rubber articles, such as pneumatic tires, for years have been vulcanized or cured in a press wherein heat is applied externally by the tire mold and internally by a curing bladder for a certain length of time to effect vulcanization of the tire. These presses, which are well known in the art, generally employ separable mold halves or parts (including segmented mold parts) with shaping and curing mechanisms, and utilize bladders into which shaping, heating and cooling fluids or media are introduced for curing the articles. The aforesaid curing presses typically are controlled by a mechanical timer or a programmable logic controller (PLC) which cycles the presses through various steps during which the article is shaped, heated and in some processes cooled prior to unloading from the press. During the curing process the article is subjected to high pressure and high temperature for a preset period of time which is set to provide sufficient cure of the thickest part of the article. The cure process usually continues to completion outside the press.
Rubber chemists are faced with the problem of predicting the time period within which each part of the rubber article will be satisfactorily cured and, once such a time period is established, the article is heated for that period. This is a relatively straight-forward analysis for a rubber article that is relatively thin and has uniform geometry and similar composition throughout. It is a much more difficult analysis when this is not the situation such as with a complex article such as a tire, and particularly with large tires such as truck tires, off-the-road tires, farm, aircraft and earthmover tires. The extent of cure in these types of tires is affected not only by the variance in geometry from part to part in the tire but also by the composition change and laminate structure as well. While the time control method has been used to cure millions of tires, because of the varying composition and geometry in the tire, some parts of the tire tend to be more cured than other parts. By setting the time period to cure the most difficult part to cure, over-cure of some parts occurs, and production time on the vulcanizing machinery is wasted and production efficiency is reduced.
Various designs for curing presses and various curing methods have been proposed to provide a more uniform cure to thick rubber articles. Some methods use differing materials for mold construction, insulating materials, differing compositions for parts of the tire, multiple curing zones so heat can be applied for a longer time, or methods for directing more heat to the thickest or most complex part of the rubber article. Patents which show various curing methods and apparatus are as follows: U.S. Pat. Nos.: 3,718,721; 3,819,915; 4,371,483; 4,044,600; 4,861,253; 5,055,245; 5,481,319; 6,413,068; and 6,478,991; EPO Patent Applications 0,485,127A1; 0,578,105A2 and 1,172,198A2; and Japanese Patents JP62037107; JP 0,7,195,370 and JP 2002,172,622A. However, none of the above methods and apparatus has proven entirely satisfactory, and time control remains the typical method of curing non-uniform thick rubber articles. Thus, the tire industry is faced with an issue of producing a uniformly cured tire in a faster time period.
The invention is directed to an improved method of curing a non-uniform, thick rubber article such as a truck tire or a tread for a tire. The method uses heat transfer elements which are specifically chosen and specifically placed in a mold to transfer heat into the article at the cure-limiting parts of the article. This results in small apertures in the articles where the heat transfer elements protrude into the article. Since these apertures are small, they do not change the relative function and performance of the article. The apertures are basically seen as pin holes or mini-sipes.
Siping is well known in the tire art to create functional advantages such as traction, water evacuation, etc. U.S. Pat. Nos. 6,196,288; 4,298,046; 5,289,862 and 5,896,905 disclose various effects of siping with tires. The distinction between the use of siping in the prior art and the use of the mini-sipes of this invention is that the siping in the prior art is directed to causing or creating a functional change in the tire where the mini-sipes of the invention are chosen to effect an improved cure without changing the relative functional performance of the tire or tread being cured.
As for the pin holes, the same distinction applies between the prior art and the invention. Pin holes in the tread are known in the tire prior art to create functional changes in wear, traction, water evacuation, performance, etc. (See U.S. Pat. Nos.: 2,504,090; 3,409,064; 3,637,001; 3,645,313; 3,749,145; 3,998,256; 4,266,592; 4,305,445; 4,723,584; 5,027,876 and 6,374,886; U.S. Patent Publication Nos. 2003/0089439 and 2002/0100527; and Great Britain Patent No. 546,975. Other patents show lateral pin holes introduced into the side of the tread of a tire to create a functional change in the tire performance. (See U.S. Pat. Nos.: 1,408,100; 1,509,259; 1,733,064; 1,778,071; 1,877,988; 3,848,651; and 4,979,549; Japanese Patent Publication No. P2002-307442A and Japanese Application No. 3-355071).

Method for curing a thick, non-uniform rubber article


A compliant interface (14,16) for vehicular seat weight sensors minimizes parasitic stresses affecting sensor output. In one embodiment, an integral compliant interface (14) has an annular flange (14a) attached to a post extending from the sensor body with a first compliant member (14r) disposed between the annular flange and an upper elongated flange (14h) of a mounting bracket (14l) and a second compliant member (14s) disposed between the annular plate and a lower elongated flange (14k) to allow pivotal movement of the sensor limited by a motion stop member (14f) of annular flange (14b) engaging the lower flange. An overload cage (14u) may be placed over the sensor and attached to an additional flange (14l) to contain the sensor in the event of a failure of the mount in a catastrophic high speed crash. According to another preferred embodiment, an interface having upper and lower body members are formed with a sensor post receiving bore (16c) for attachment to the post. The body members are formed with spaced apart, radially extending face surfaces, each formed with an annular recess aligned with each other and with a compliant member received therein and fixed to the respective body members and extending beyond the face surfaces. The interface is received through a bore of a support plate to which the sensor is mounted with the compliant members engaging opposite face surfaces of the support plate allowing limited pivotal motion and with a compliant member limiting lateral movement of the interface relative to the support plate.

Governmental legislation requires the development of a system capable of sensing information related to front passenger seat occupants and classifying such occupants to the extent necessary to adapt airbag deployment to improve passenger safety. For example, airbag deployment can be a problem for small children or children in car seats occupying a front passenger seat. Using information provided by vehicular seat weight sensors, a control system can override the normal airbag actuation mechanism and prevent airbag deployment when such child occupies a seat having appropriate weight sensors. In other situations, airbag deployment can remain active but its intensity can be modulated in response to sensed weight information, for example, when the occupant is incorrectly positioned or is within some intermediate weight classification.
Vehicular weight sensors in such a system would be disposed, for example, between a first frame or riser attached to the chassis of the vehicle and a second frame that supports the seat. In the case of movably mounted passenger seats, the second frame typically comprises an upper track adjustably movable on a lower track with the seat structure mounted on the upper track. Sensors can also be mounted between an upper track and a side member.
An example of a suitable weight sensor is shown and described in copending application Ser. No. 10/874,963 filed Jun. 23, 2004 claiming the benefit of Provisional Application No. 60/491,417, filed Jul. 31, 2003 and assigned to the assignee of the instant invention, the subject matter of which is incorporated herein by this reference. Such weight sensors have, inter alia, a first body formed with a sense surface on which strain sensors are disposed and have a mounting post extending away from the first body. A second body is provided with a tubular wall, the distal free end of which is attached to the first body around the perimeter of the sense surface and has a second mounting post extending away from the second body in a direction opposite that of the post of the first body generally along a common longitudinal axis. Essentially, weight is transmitted as a force to the first body creating a strain on the sense surface.
Performance of the weight sensors of the type described in the above referenced application is directly related to parasitic loads at the interface of the sensors with surrounding components such as the track, riser and the like. By way of example, the tracks on opposite sides of the seat may be somewhat out of parallel with each other even when they are within specified tolerances and this can place a moment on the sensors creating a parasitic stress that affects the sensor output.

Sensor mounting apparatus for minimizing parasitic stress


A method and a system for regulating power in a portable audio/video playback device enabling the portable audio/video playback device to completely play an audio/video multimedia file or data without sufficient power or external power. A processing unit is employed for detecting a remaining power of the portable audio/video playback device and for computing an average power consumption rate and a remaining playback time of the audio/video multimedia file or data to thereby appropriately reduce an output level of the video or audio output signals. Accordingly, power consumption of the portable audio/video playback device is minimized so that a complete playback of the audio/video multimedia file or data can be performed by the portable audio/video playback device before the power is exhausted.

1. Field of the Invention
The present invention relates to a method and a system for regulating power in a portable audio/video playback device, and particularly, to a method and a system for a complete playback of an audio/video multimedia file or data by power regulation provided that the power supplied to a portable audio/video playback device is insufficient.
2. Description of the Related Art
As technology changes rapidly, audio and video devices are now in widespread use and multimedia players have become indispensable to everyday life in modem society. For example, household television sets, VCD/DVD players and various stereo systems are all designed to provide the users with better audio and video pleasures. Thanks to technology development, audio and video devices have been gradually miniaturized, and thus a portable audio/video player has been proposed, which makes it possible for the users to watch and listen to a multimedia file or data in the outdoors. However, such a portable audio/video player is usually subject to the limitation of power supply and therefore is very inconvenient in use.
In a portable audio/video player, such as an MP3 player or a notebook computer, in the current market, a battery is installed therein to provide the power required for the playback of the multimedia file or data. However, without an external charger, the battery usually lasts only about two hours. For example, an independent power supplied only by a battery of a notebook computer usually runs out before the completion of the playback of a film recorded in DVD format. Such a playback interruption depresses the user and creates an uncomfortable experience.
In the prior art, attempts for improving the structure of a battery to thus enhance the power duration thereof have been proposed. Alternatively, an external power saving device appended to the portable audio/video player has also been proposed to minimize the power consumption thereof. However, such methods or devices still fail to provide a solution for a user to watch a film or listen to a song completely. That is, the playback of the multimedia file will be interrupted when the power runs out, which impresses the user with an uncomfortable experience.
As can be seen from the description, the independent power of a conventional portable audio/video players is easily exhausted, which causes a playback interruption of a film or a song. The failure to provide a user with a complete audio or video pleasure makes it inconvenient in use. In the light of the above, the inventor has employed technical ideas and developed an innovative invention with reasonable design to improve the drawbacks.

Method and system for regulating power in portable audio/video playback device


A constant voltage circuit obtains an accurate constant voltage output by reducing the influence of channel length modulation effect of a MOS transistor. A current mirror circuit having two P-channel MOS transistors and two N-channel MOS transistors is added in addition to a main circuit having three P-channel MOS transistors, two N-channel MOS transistors and two resistors. The part of the voltage of the main circuit is input to the current mirror circuit, the output of the current mirror circuit is fed back to the main circuit, and a constant voltage is obtained as the output of the main circuit.

This invention relates to a constant voltage circuit containing a MOS type integrated circuit and, more particularly, to an improvement to delete the change of an output voltage due to a channel length modulation effect of a MOS transistor.
An example of a conventional constant voltage circuit is shown in FIG. 1. This constant voltage circuit comprises three P-channel MOS transistors P1, P2, P3, two N-channel MOS transistors N1, N2 and two resistors R1, R2.
In the constant voltage circuit of an arrangement as shown in FIG. 1, a current flowing in series through the MOS transistor P1, the resistor R1 and the MOS transistor N1 is I1, a current flowing in series through the MOS transistors P2 and N2 is I2, and a current flowing in series through the MOS transistor P3 and the resistor R2 is I3.
The operation of the constant voltage circuit of FIG. 1 will be simply described. The channel widths of the MOS transistors P1, P2, P3, N1, N2 are respectively WP1, WP2, WP3, WN1, WN2, and the channel lengths of these MOS transistors P1, P2, P3, N1, N2 are respectively LP1, LP2, LP3, LN1, LN2. At this time, the relationship among the LP1, LP2, LP3, LN1, LN2 are set to LP1=LP2=LP3, and LN1=LN2.
The gates of the MOS transistors P1 and P2 are commonly connected, the gate of the MOS transistor P2 is connected to the drain of the same MOS transistor P2, and both the MOS transistors constitute a current mirror circuit. And, the following equation is satisfied in the relationship among the WP2, WP1, I2 and I1: EQU WP2/WP1=I2/I1 (1)
Further, the MOS transistors N1, N2 are together operated in a weak inversion region. The gradient of the drain current (logarithm) characteristics to the gate voltage in the weak inversion region is assumed as 1/K. The drain currents of the N-channel MOS transistors when the gate voltage of the N-channel MOS transistor are Vg1. Vg2 are respectively Id1, Id2, the following equation is obtained: EQU 1/K={1n(Id1)-1n(Id2)}/(Vg1-Vg2) (2)
Accordingly, the following equation is obtained: EQU Id1/Id2=exp{(Vg1-Vg2)/K} (3)
That is, when the gate voltages of the N-channel MOS transistors N1, N2 are V11, V12, the following equations are satisfied via I0/L set as a constant. EQU I1=(I0/L).multidot.WN1.multidot.exp{V11/K} EQU I2=(I0/L).multidot.WN2.multidot.exp{V12/K}
Accordingly, EQU I1/I2=(WN1/WN2).multidot.exp{(V11-V12)/K} (4)
Hence, the following equation is obtained: ##EQU1## Accordingly, from the equations (1) and (5), the following equation is induced. EQU I1.multidot.R1=K.multidot.1n{(WP1/WP2).multidot.(WN2/WN1)} (6)
In the equation (6), the K is determined according to the manufacturing process, and the I1 is set to a desired value by suitably determining the values of the WP1, WP2, WN1, WN2 and R1. At this time, since the equation (6) does not have a parameter depending upon a power source voltage, a constant-current operation is theoretically realized for the power source voltage. Further, since the MOS transistor P3 constitutes a current mirror circuit together with the MOS transistor P2, WP2/WP1=I2/I1, WP3/WP2=I3/I2 are satisfied, and the following equation is obtained: EQU WP3/WP1=I3/I1 (7)
Hence, the MOS transistor P3 is operated as a constant-current source for the power source voltage, and an output voltage Vout is given by the following equation: EQU Vout=I3.multidot.R2 (8)
More specifically, the output voltage Vout does not depend upon the power source voltage VDD but makes it possible to be a constant value.
In the conventional constant voltage circuit, it has been described that the output voltage Vout of the constant value can be always obtained without depending upon the power source voltage VDD. However, this is the case that the channel length modulation effect of the MOS transistor is not considered at all. The channel length modulation effect of the MOS transistor means, as shown in FIG. 2, the phenomenon that, as a voltage VDS between the drain and the source increases, a current IDS between the drain and the source increases. More specifically, in the saturated region of the MOS transistor (Vds.gtoreq.VGS-VTH) (where the VTH is a threshold voltage), the IDS has a gradient depending upon the VDS according to the channel length modulation effect (In FIG. 2, the VGS show the two characteristics of VGS1 and VGS2).
Accordingly, in the conventional circuit shown in FIG. 1, P-channel and N-channel MOS transistor threshold voltages are VTHP, VTHN. Since the V11, V12 become near the VTHN, the gate voltage V2 of the P-channel MOS transistor P3 becomes near VDD-.vertline.VTHP.vertline. and the Vout becomes a set predetermined voltage as the power source voltage VDD increases, the VDSs of the MOS transistors P1, P3, N2 increase as the VDD increases. Therefore, channel length modulation effect takes places, and hence the I1, I2, I3 to be originally determined according to the ratio of the WP1, WP2, WP3 cause an error to occur. When the I1 increases due to the channel length modulation effect, the voltages drop of I1.R1 is increased, the gate bias of the MOS transistor N2 is shifted to the GND side, and hence it acts so as to suppress the I2. However, since the increased current due to the channel length modulation effect of the currents I1, I3 predominantly acted, the output voltage Vout given by the previous equation (8) becomes as follows when the current increase of the I3 is .DELTA.I3, EQU Vout=(I3+.DELTA.I3).multidot.R2 (9)
the output voltage Vout depends upon the power source voltage in the operating region A of the constant voltage circuit as shown in FIG. 3, and exhibits the characteristics that it becomes larger than the theoretical value. Normally, in the case of the Vout in the order of several volts, when the power source voltage changes at 1V, the output voltage Vout varies about several mV to 100 mV. This decreases the accuracy of the constant voltage output with the result that the reliability of the LSI is impaired.
Heretofore, to eliminate the malfunction, the channel lengths of the respective MOS transistors has been elongated to suppress the changes to the minimum limit. However, this method has a limit, and in this case, the occupying area of the constant voltage circuit on a semiconductor chip is increased.
It is therefore an object of the present invention to provide an accurate constant voltage circuit by reducing the influence of the channel length modulation effect of a MOS transistor.