The present invention provides a mutual capacitance touch sensitive sensing method, including: sequentially charging multiple driving electrode sets and detecting the electrical change of multiple sensing electrodes; sequentially charging multiple driving electrodes in a driving electrode set and detecting the electrical change of the sensing electrodes when the electrical change of at least one of the sensing electrodes is detected while driving the driving electrode set; and determining the touch location according to the detected electrical change.

Technical Field
The present invention relates to a touch sensing method. More particularly, the present invention relates to a mutual capacitance touch sensitive sensing method.
Description of Related Art
Touch sensitive panel is one of the major human-machine interfaces nowadays, especially the mutual capacitance touch sensing panel that can provide better sensing accuracy. Please refer to FIG. 1, which is a perspective view of a conventional mutual capacitance touch sensing system 100. The touch sensing system 100 includes multiple first electrodes (or driving electrode lines) 120 and multiple second electrodes (or sensing electrode lines) 130 which are disposed in a touch sensing region. These first and second electrodes 120 and 130 are both connected to a sensing apparatus 110. The sensing apparatus 110 transmits the detected touch event information to other circuits or modules (e.g. the main processor of a computer system) via other interfaces.
Several areas, where the first electrodes 120 overlap but are not in contact with the second electrodes 130, exists between the first and the second electrodes 120 and 130. During one scanning cycle of the touch sensing region, the sensing apparatus 110 sequentially charges the first electrodes 120 to send driving signal, and then charges the second electrodes 130 to conduct touch sensing. When a certain first electrode 120 is charged and the electrical change is detected on a certain second electrode 130, the sensing apparatus 110 could then determine that the touch event takes place in the area or near the area where the certain first electrode 120 overlaps the certain second electrode 130.
In order to scan all the areas in the touch sensing region in one scanning cycle, each of the first electrodes 120 must be charged once sequentially. Assuming that the second electrodes 130 conducting touch sensing simultaneously requires time t, and the number of the first electrodes 120 is M, then the total time of one scanning cycle of the touch sensing region would be M multiplying t. Meanwhile, due to the users' increasing requirements for touch sensing efficiency, the sensing apparatus 110 has to respond to the system more and more frequently. As a result, there is a demand in the market for a touch sensing method and system that could decrease the time for scanning the touch sensing region and increase the touch report rate.

Mutual capacitance touch sensitive sensing apparatus and system and method thereof


A decoding system (1) is provided in which a memory transfer block (14) stores an input transport stream into a memory (16) and the top address of each TS packet into an address memory (15), a CPU (21) refers to information stored in the address memory (15) to access each packet in a memory (16) and analyze header information in the packet, the CPU (21) generates a transfer instruction to transfer data from the memory (16) to a decoder (19 or 20) for each access unit (one frame, for example) and supplies it to a DMA circuit (17 or 18), and the DMA circuit (17 or 18) reads the data from the memory (16) and transfers it to the decoder (19 or 20) according to the transfer instruction supplied from the CPU (21).

1. Field of the Invention
The present invention generally relates to the technical field of data distribution, and more particularly to a data distribution apparatus and method, in which an input multiplexed stream formed by multiplexing video data, audio data, etc. on a plurality of channels in units of a packet is demultiplexed according to each channel and each of the demultiplexed data is distributed to a decoder on a corresponding one of the channels.
This application claims the priority of the Japanese Patent Application No. 2002-196277 filed on Jul. 4, 2002, the entirety of which is incorporated by reference herein.
2. Description of the Related Art
For distribution of digital contents over a network, a plurality of elementary streams such as video data, audio data, text data, program data and other system data necessary for transmission, supplied from a plurality of data encoders, is multiplexed at the sending side. The distributed multiplexed stream is demultiplexed by a demultiplexer at the receiving side into a plurality of elementary streams each of which is distributed to a decoder on a corresponding channel.
For demultiplexing a multiplexed stream into a plurality of elementary streams, the conventional demultiplexer analyzes the number of elementary stream channels included in the multiplexed stream, and pre-divides a memory area for data on each of the channels. Then, the demultiplexer stores an input packet into a a divisional memory area for data on a corresponding channel. The division of the memory area for each of the channels is effected in a first session done after the multiplexed stream is supplied.
In some cases, however, the number of channels of data included in a multiplexed stream varies dynamically as the time elapses. For example, in a TV conference system or the like over which a plurality of users has a talk with each other, when an additional user participates in the conference or any of the participants leaves the conference, the number of channels will vary dynamically. When the number of channels varies dynamically, division of the memory area by a number of channels determined at the start of a session will lead to an insufficient number of channel areas formed in the memory or result in an unused memory area in the course of data transfer.
Also, the packet distribution in which it is judged to which channel an input packet corresponds and the input packet is stored into a corresponding memory area has to be done on the real-time basis. Also, the amount of processing in the packet distribution is large. Therefore, if a main controller used by other circuits as well is let to make the packet distribution in addition, the burden to the main controller will be increased since the packet distribution has to be done on the real-time basis. Further, even if a hardware is provided independently of the main controller to effect the packet distribution, the circuit scale will be larger since the amount of processing is large.


Provided are a memory controller for controlling a refresh cycle of a memory and a method thereof. In this method, a temperature measure command is generated to measure an operating temperature of the memory. Next, a measured temperature in response to the temperature measure command is received. Then, a temperature difference between the measured temperature and a reference temperature is detected if the measured temperature is different from the reference temperature to change the refresh cycle according to the temperature difference, and if the measured temperature is equal to the reference temperature the method returns to the temperature measure command generating step. Thereafter, a refresh command is applied to the memory in response to the changed refresh cycle.

1. Technical Field
The present invention relates to a memory controller, and more particularly, to a memory controller for controlling a refresh cycle of an external memory and a method thereof.
2. Discussion of the Related Art
In general, data is stored as charges in capacitors located in dynamic random access memory (DRAM) cells. Because the capacitors on which the charges are stored are not perfect, their stored charges leak over time. Thus, a process for reading out data from the DRAM cells and rewriting the data back to the DRAM cells needs to be repeated before the data stored in the capacitors is lost. This process is called a refresh operation.
In principle, computers cannot use DRAMs during the refresh operation. For example, the time required to perform one refresh operation is equal to a cycle time of a common write operation, thus after the time for performing the refresh operation has passed, external computers cannot use the DRAMs. The time during which the DRAMs cannot be used due to the refresh operation is called a busy rate. As such, computers are typically designed to have a busy rate as short as possible. When computer systems are in a sleep mode, most of the systems' internal devices are turned off, while the DRAMs therein are refreshed to maintain their data. Accordingly, a self refresh current flows through the DRAMs. Thus, it is important for battery-operated computer systems to reduce their self refresh current.
A recent trend in the development of computer systems is to change a refresh cycle according to temperature variations and thus reduce the refresh current. For example, a frequency of a refresh clock is lowered by dividing temperatures into several levels from low to high and then using a low temperature to reduce the current consumption of a computer system. This development trend is based on the fact that DRAMs retain data for a longer time when they are subject to lower temperatures.
In system-on-a-chip (SOC) products and/or system-in-a-package (SIP) technology, which involve stacking memory chips, e.g., negative AND (NAND) flash memory chips, synchronous dynamic random access memory (SDRAM) chips, or double data rate (DDR) SDRAM chips in a single package, the heat generated by processors used, for example, in the SOC or SIP products is directly transferred to the memory chips disposed above the processors.
When using the SOC or SIP products, the heat generated during a refresh operation causes DRAMs, which are adversely affected by excess heat, to deteriorate. Thus, a time during which the DRAMs can retain data is reduced due to the heat generated by the processors or circumferential environments. One method used to prevent the deterioration of DRAMs due to excess heat is to assume the worst-case temperature conditions during the design process of the DRAMs, and thus, shorten the auto refresh cycle for the DRAMs.
In addition, as hand-held devices require high-performance and various multi-media functions as well as high speed data communication capabilities, the performance of their DRAMs is also important. Therefore, the SOC or SIP products must also deal with performance degradation resulting from an auto refresh command cycle that has been shortened to compensate for the worst-case temperature conditions.
The above method of shortening the auto refresh cycle is typically the only way to retain the data of the DRAMs when temperatures are at their highest levels, namely, when refresh operations of the DRAMs are in the worst case. However, because the auto refresh cycle of the DRAMs is determined under the worst case, the performance of the DRAMs in the SOC or SIP products deteriorates except when the temperatures are at their highest levels.

Memory controller for controlling a refresh cycle of a memory and a method thereof


A cellular radio system at least one transceiver which receives a signal packed into frames, a coder for channel coding the signal received by the transceiver prior to transmitting the signal as bits, and a vocoder for source coding the signal. The coder forms and adds check bits to the signal to be transmitted, the check bits being used in detecting errors causes by transmitting the signal. The coder adds the check bits in the channel coding to reduce the number of bits in the frames received by the transceiver.

The standard TIA/EIA IS-95 defines channel coding carried out for the signal in a base station of a cellular radio system. The standard defines the channel coding employed in data transfer on an Air interface between a base station and a subscriber terminal of a cellular radio system. The standard defines the channel coding to be carried out in a channel coder of the base station. In the channel coder defined by the standard, the signal is CRC block-encoded (CRC=Cyclic Redundancy Check), convolutional-coded and interleaved. The interleaving is followed by converting the signal into an RF signal and transmitting it on the radio path to the subscriber terminal.
The standard TIA/EIA IS-96 determines a variable-rate speech encoder employed in the cellular radio network. As the variable-rate encoder, for example a CELP vocoder (CELP=Code Excited Linear Predictive) has been used. The standard defines PCB (PCB=Parity Check Bits) and CRC calculation for several different data rates, such as 1200 kbit/s, 2400 kbit/s, 4800 kbit/s and 9600 kbit/s. In addition, the standard defines signal interleaving for all the abovementioned data rates. The PCB calculation has in the standard been defined to be carried out in the vocoder in connection with the source coding. In prior art, the vocoder is in the TRAU unit (TRAU=Transcoder/Rate Adaptor Unit), located apart from the base station. The TRAU unit is located, for example, at the base station controller or the mobile services switching center.
The TRAU unit is used in signal source coding, adapting the data rate to be suitable for the transfer network, e.g. the PSTN network (PSTN=Public Switched Telephone Network), and for transmitting TRAU frames to the base station. The TRAU unit codes the 64 kbit/s signal originating from the PSTN network to a 16 kbit signal, whereby the user data rates are at the aforementioned levels. The TRAU unit serves as the source coder, reducing the bandwidth on the Air interface between the base station and the subscriber terminal.
The prior art TRAU frame is, e.g. 192 bits long before and after the convolutional coding. The convolutional coding is carried out in the channel coder. It takes 20 ms to transmit a frame. The frame comprises, e.g., 172 information bits, 12 CRC bits and 8 tail bits. In the aforementioned case, the data rate is 9600 kbit/s. The frame comprises one MM bit (MM=Mixed Mode Bit). The remaining part of said frame, i.e. 171 bits, is allocated for traffic.
In prior art, the calculation of PCB bits, the coding and decoding of PCB bits is carried out in the vocoder i.e. the TRAU unit. The calculation, coding and decoding of the bits requires bit buffering, which causes delay. The CRC block encoding is performed at the base station in connection with channel coding. In calculating CRC block encoding and bit interleaving, additional buffering is required, resulting in additional delay. In addition, the prior art solution takes up a lot of transmission path capacity.

Data transfer method and a cellular radio system


A drawer includes: a photosensitive drum; a drawer frame; a connector; a drawer memory; and a holder. The photosensitive drum is rotatable about a drum axis extending in a first direction. The drawer frame holds the photosensitive drum. The drawer frame has an outer surface. The connector has a plurality of terminals arrayed in an arraying direction. The drawer memory stores information on the photosensitive drum. The drawer memory is electrically connectable to at least one of the plurality of terminals. The holder is positioned at the outer surface of the drawer frame and holds the connector. The holder is movable relative to the drawer frame in the arraying direction of the plurality of terminals.

There has been known an electro-photographic type image forming apparatus such as a laser printer and an LED printer. The image forming apparatus includes a drawer. The drawer includes a plurality of photosensitive drums. A plurality of developing cartridges is attachable to and detachable from the drawer. Each of the plurality of developing cartridges includes a developing roller, and upon attachment of the developing cartridge to the drawer, the developing roller provided in the developing cartridge is in contact with a corresponding one of the photosensitive drums of the drawer. The drawer is attachable to and detachable from a housing of a main body of the image forming apparatus in a state where the developing cartridges are attached thereto.

Drawer including drawer frame, connector, and holder holding the same and movable relative to drawer frame


The invention concerns a process and a device for measuring angles relative to the horizontal plane of elements in vehicles, with at least one laser (L) and at least one target (Z), which are located via adapters (10, 20, 30, 40) on the element to be measured in such a manner that the at least one laser (L) and the at least one target (Z) are located in one horizontal plane parallel to the plane of the element to be surveyed, wherein the adapters (10, 20, 30, 40) are designed such that the at least one laser (L) is situated parallel to the axis of the first of the two elements to be measured and the at least one target (Z) is situated perpendicular to the axis of the second of the two elements to be measured.

1. Field of the Invention
The invention concerns a process and a device for measuring angles in the horizontal plane.
2. Description of the Related Art
In order to determine the angle of tilt of an element with respect to the horizontal plane, generally use is made of gravity. For example, U.S. Pat. No. 4,707,927 discloses an inclination sensor, which measures its spatial tilt with respect to the horizontal plane by means of an electrically conductive fluid, which is enclosed in a spherical intermediate space, which is formed by a spherical common electrode and four opposing suitably shaped detecting electrodes. The liquid moves according to the angle of tilt of the sensor, thereby setting up electrostatic capacity between the electrodes, which is detected using readout electronics. Further, it is known from U.S. Pat. No. 4,716,534 to use a sensor for measuring the angular alignment of a reference surface in relation to the gravitational vector, using a rotatably mounted disk upon which a weight is mounted eccentrically to keep the disk in a relatively constant position relative to the gravitational vector, which disc is provided with graduated markings along the edge, which markings are electronically detectable, e.g. by a photodetector. This type of angular measurement is however not suitable to measure angles in the horizontal plane (angle of tilt). For this, it is necessary to employ optical measuring processes, for example involving a laser.

Process and device for measuring angles in the horizontal plane


An access system for a wireless local area network is provided. The access system initiates operation in a first frequency band of a plurality of frequency bands of the wireless local area network to provide one or more wireless client devices of the wireless local area network with access to a wireless wide area network. The access system also processes one or more association requests received in the first frequency band to identify one or more associated wireless client device. The access system also determines whether each of the one or more associated wireless client devices supports a second frequency band. The access system also sends a request to the one or more associated wireless client devices to transition from the first frequency band to the second frequency band based on determining that each of the one or more associated wireless client devices supports the second frequency band.

The present disclosure generally relates to wireless communication systems, and in particular, to intelligent band selection for wireless access points.
Wireless local area networks have greatly improved the ways in which users access information on the Internet. Accessing a wireless local area network may require a user to select a wireless access point within the wireless local area network. A wireless device may choose to act as an access point instead of a client, such as when it acts as a mobile hotspot to serve client devices. When doing so, the wireless device may select a frequency band to provide the client devices access to the wireless local area network.

Intelligent band selection for wireless access point


A gradient calculation system efficiently calculates precise gradients for planar surfaces of primitives in computer graphics systems using exact closed form solutions. The system is particularly suited for calculating gradients to enable selection of an appropriate texture map resolution in a texture mapping system. In architecture, the gradient calculation system can be implemented in software, hardware, or a combination thereof, and is more particularly implemented as follows. A texture mapping system is provided with a plurality of MIP maps with different texel resolutions. A gradient calculation system associated with the texture mapping system computes texel gradients relative to a pixel of a primitive using closed form equations that result in exact gradients. MIP map selection logic associated with the texture mapping system selects an appropriate MIP map for the pixel from the plurality of MIP maps based upon the calculated exact gradients. Optionally, the system may further include a performance optimization feature for assigning the appropriate MIP map to subsequent pixels of, preferably, the entire primitive, or secondarily, to subsequent pixels of a span of the primitive, when certain gradient criteria are met.

Computer graphics systems commonly are used for displaying graphical representations of objects on a two dimensional computer display screen. Current computer graphics systems can provide highly detailed representations and are used in a variety of applications.
In typical computer graphics systems, an object to be represented on the computer display screen is broken down into a plurality of graphics primitives, a triangular example of which is shown in FIG. 1 and designated by reference numeral 11. Primitives 11 are basic components of a graphics picture and may include points, vectors (lines), and polygons, such as the triangular primitive 11 of FIG. 1. Each triangular primitive 11 is made up of spans 12 of picture elements 13 (pixels). Hardware and/or software is implemented to render, or draw, on the two-dimensional display screen, the graphics primitives 11 that represent the view of one or more objects being represented on the screen.
The primitives 11 that define the three-dimensional object to be rendered are typically provided by a central processing unit (CPU), which defines each primitive 11 in terms of primitive data. For example, when the primitive 11 is a triangular primitive 11, then the CPU may define the primitive 11 in terms of the x', y', z' pixel coordinates (unnormalized orthogonal coordinate system) of its vertices, as well as the color values (R, G, B values) of each vertex. Rendering hardware interpolates the data from the CPU in order to produce the x, y, z screen coordinates (normalized orthogonal coordinate system) corresponding with the pixels 13 that are activated/deactivated to represent each primitive 11 and the color values (R, G , B values) for each of the screen coordinates x, y, z.
Early graphics systems failed to display images in a sufficiently realistic manner to represent complex three-dimensional objects. The images displayed by such systems exhibited extremely smooth surfaces, absent textures, bumps, scratches, shadows, and other unrealistic surface details. As a result, methods were developed to display images with improved surface detail. Texture mapping is one such method that involves mapping a source image, referred to as a texture, onto a surface of a three-dimensional object, and thereafter mapping the textured three-dimensional object to the two-dimensional graphics display screen to display the resulting image. Surface detail attributes that are commonly texture mapped include, for example, color, specular reflection, transparency, shadows, surface irregularities, etc.
Texture mapping involves applying one or more texture map elements, or texels, of a texture to each pixel 13 of the displayed portion of the object to which the texture is being mapped. Each texel in a texture map is defined by coordinates (generally two or more spatial coordinates, e.g., s, t, and, sometimes, a homogeneous texture effect parameter q) which identify its location in the texture map (two-dimensional or greater). For each pixel 13, the corresponding texel(s) that maps to the pixel 13 is accessed from the texture map via the texel coordinates (e.g., s, t, q of an orthogonal coordinate system) associated with that pixel 13 and is incorporated into the final R, G, B values generated for the pixel 13 to represent the textured object on the display screen. It should be understood that each pixel 13 in an object primitive may not map in a one-to-one correspondence with a single texel in the texture map for every view of the object.
Texture mapping systems typically store data in memory representing a texture associated with the object being rendered. As indicated above, a pixel 13 may map to multiple texels 15. If it is necessary for the texture mapping system to read a large number of texels 15 that map to a pixel 13 from memory to generate an average value, then a large number of memory reads and the averaging of many texel values would be required, which would undesirably consume time and degrade system performance.
To overcome this problem, a well known scheme has been developed that involves the creation of a series of MIP (multum in parvo, or many things in a small place) maps for each texture, and storing the MIP maps of the texture associated with the object being rendered in memory. A set of MIP maps for a texture includes a base map that corresponds directly to the texture map as well as a series of related filtered maps, wherein each successive map is reduced in size by a factor in each of the texture map dimensions (s, t, which may differ). In a sense, the MIP maps represent different resolutions of the texture map.
An illustrative example of a set of MIP maps is shown in FIG. 2 In this simplified example, the MIP maps of FIG. 2 are two dimensional (s, t) and include a base map 14a (the reference) that is eight-by-eight texels 15 in size, as well as a series of maps 14b, 14c, and 14d that are respectively four-by-four texels 15, two-by-two texels 15, and one texel 15 in size. The four-by-four map 14b is generated by box filtering (downsampling) the base map 14a. With box filtering, each texel 15 in the map 14b corresponds to an equally weighted average of four adjacent texels 15 in the base map 14a. Further, the two-by-two map 14c is similarly generated by box filtering map 14b. Finally, the single texel 15 in map 14d is generated by box averaging the four texels 15 in map 14c.
The computer graphics system determines which MIP map 14 in a series of MIP maps 14a14d to access in order to provide the appropriate texture data for a particular pixel 13 based upon the number of texels 15 to which the pixel 13 maps. For example, if the pixel 13 maps in a one-to-one correspondence with a single texel 15 in the texture map, then the base map 14a is accessed. However, if the pixel maps to four, sixteen, or sixty-four texels, then the maps 14b, 14c and 14d are respectively accessed because those maps respectively store texel data representing an average of four, sixteen, and sixty-four texels 15 in the texture map.
In order to determine the number of texels 15 to which a pixel 13 maps so that the appropriate MIP map 14 can be accessed, gradients (mathematical derivatives) of the various texel coordinates with respect to screen coordinates are computed. In this regard, gradient values .differential.i/.differential.x, .differential.i/.differential.j, where i is s, t, and/or q in the texel domain and where x, y are screen coordinates, are calculated. These gradients reflect the rate of change of texture coordinates 15 relative to pixel coordinates 13. Often, a single gradient is allocated to each pixel 13 by selecting the largest gradient.
Prior methods for determining the gradients rely on using some form of either a linear difference formula or a central difference formula The former is more popular than the latter due, in part, to its simplicity and ease of implementation.
With the linear difference formula, each gradient derivative is essentially equal to an old gradient derivative plus a constant. Given the gradient at the vertices of a triangular primitive 11, the gradients along the edges as well as along the spans 12 of the primitive 11 are linearly approximated.
When the central difference formula is employed, each gradient derivative is essentially equal to a weighted sum of nearby gradient derivatives. For more details regarding the use of the central difference formula, see A. Watt and M. Watt, Advanced Animation and Rendering Techniques, Addison-Wesley, pp. 300-301 (edition 1995).
Although meritorious to an extent, these methods for calculating gradients are inaccurate, especially for highly spatially perspected rendered primitives 11. The larger the primitive 11, the more spatially perspected and the greater the error. Furthermore, these methods are computationally complex for the degree of accuracy that is accomplished.
Thus, an unaddressed need exists in the industry for a more efficient system and method for determining precise gradients in a texture mapping system of a computer graphics system.

Precise gradient calculation system and method for a texture mapping system of a computer graphics system


An anti-reversing pawl mechanism is claimed that includes a pawl that is engaged by a flexible coupling but that is also biased toward a driven member such that when the engagement of the flexible coupling is removed, the pawl engages the driven member and stops it from moving.

Cable pullers are used by electrical contractors to pull cables through pipe or conduit so that the cables can be terminated at either end. Once terminated, these cables can be used to supply power or data between locations. In particular, cables that supply power can require significant forces in order to be pulled. For this reason, cable pullers are used that typically comprise a motor that powers a drive sprocket, which then transmits torque to a capstan around which a pulling rope can be wound. It is often the case that a drive chain is the means used to connect the capstan to the drive sprocket so that the torque from the motor can be transmitted to the capstan. The capstan is configured to rotate in a primary direction during which the pulling rope is wrapped around the capstan, causing the wire or cable to be pulled through the conduit.
In use, the pulling rope is fished through the conduit by means commonly known in the art after it has been attached to the cable that is to be pulled. Once the cable puller is turned on, the motor causes the drive sprocket to rotate, which transmits its torque to another sprocket to which the capstan is connected by the drive chain. As the capstan begins to rotate, the pulling rope is wound around it such that the user can pull onto its tail end. This arrangement creates a great amount of mechanical advantage, aiding in pulling the cable through the conduit. During a cable pull, great amounts of force in the order of magnitude of thousands of pounds can be exerted on the components of the cable puller. Consequently, these parts can become stressed and can be damaged or broken, including the drive chain. If the drive chain should break, it is very undesirable that the capstan should rotate in a direction that is opposite to the primary direction for a host of reasons including safety.
For this reason, an anti-reversing pawl is often employed such that if the capstan should rotate in the wrong direction, the pawl will engage the capstan and stop it from moving. Pawl mechanisms that have been previously employed are needlessly complex and require too much time to assemble, making them costly. In addition, they often continuously engage the teeth that are part of the sprocket that drives the capstan, which is an ineffective method for pulling rope when the capstan is operating at high speeds because of the drag it creates on the sprocket. Another drawback of this design is that it creates a significant amount of noise as the pawl engages each individual tooth of the sprocket. Yet another drawback is that there is wear on the part of the pawl that engages the sprocket, which could adversely affect the manner in which the pawl engages the sprocket when it needs to prevent the capstan from reversing its direction. Accordingly, there exists a need for an anti-reversing pawl mechanism that is simpler, cheaper, quieter, more robust, and that will work effectively at high speeds without creating unnecessary drag.


A surgical device is disclosed, and includes a probe having a handle assembly and an electrode assembly extending distally therefrom. An optical member is disposed on the probe and has a first set of light transmitting properties corresponding to a first set of physical parameters of the probe. The probe is configured to transition to a second set of physical parameters, the second set of physical parameters being different from the first set of physical parameters. The optical member is configured to transition from the first set of light transmitting properties to a second set of light transmitting properties, the second set of light transmitting properties corresponding to the second set of physical parameters, the second set of light transmitting properties being different from the first set of light transmitting properties.

1. Technical Field
The present disclosure relates generally to an electrosurgical device, and more particularly to one or more probes including a needle and an electrode for treating tissue, as well as an optical fiber for the detection of the changing physical characteristics of the probe.
2. Background of Related Art
Electrosurgical instruments are commonly used in open and minimally invasive surgical procedures. Because nerve and muscle stimulation cease at 100,000 cycles per second (100 kHz), electrosurgical procedures can be performed safely at radio frequencies ("RF") above 100 kHz. At these frequencies, electrosurgical energy can pass through a patient with minimal neuromuscular stimulation.
Electrosurgery involves application of high RF electrical current to a surgical site to cut, ablate, or coagulate tissue. In bipolar electrosurgery, one of a pair of electrodes of an instrument is an active electrode and the other a return electrode. The return electrode is placed in close proximity to the active electrode such that an electrical circuit is formed between the two electrodes, e.g., electrosurgical forceps, graspers, pencils, and the like. In this manner, the applied electrical current is limited to the body tissue positioned between the electrodes. When the electrodes are sufficiently separated from one another, the electrical circuit is open and thus incidental contact of body tissue with either of the separated electrodes inhibits current flow.
In monopolar electrosurgery, a source or active electrode delivers RF energy from the electrosurgical generator to the tissue and a return electrode carries the current back to the generator. The source electrode is typically part of the surgical instrument held by the surgeon and applied to the tissue to be treated. A patient return electrode is placed remotely from the active electrode to carry the current back to the generator.
In both monopolar and bipolar applications, RF energy may be delivered to targeted tissue by a probe. In use, the probe typically includes a needle and is advanced through tissue to a desired position either prior to or during application of energy to tissue. However, due to the remote placement of the probe or needle with respect to an operator, it is challenging to monitor the changing conditions of the site of the electrosurgical procedure. Accordingly, it would be desirable to provide such a probe having the capability to provide feedback to an operator on the performance and the condition of the probe and surrounding tissue, e.g., temperature, mechanical strain, and other relevant characteristics. It would be further desirable to provide a thermal profile or map of a tissue site.

Ablation needle including fiber Bragg grating


In a method for identifying a living tissue in an ultrasonic diagnosis, the elasticity of a living tissue to be diagnosed is measured for each local small area by using ultrasound. Elasticity data for each kind of known living tissue is composed of an elasticity modulus frequency histogram in each local small area for each kind of living tissue and is managed in a data library. Regarding the elasticity data serving as the measurement results, the kind of living tissue to be diagnosed is identified by using the elastic data for each kind of known living tissue.

Until now myocardial infarction, angina pectoris, cerebral infarction, and so on have been considered to be the development of a stenosis on a blood vessel which perfuses organs. However, it has become evident that these diseases are caused by the susceptibility of an atheroma to rupture. The atheroma is a blood wall disease. Actually according to a clinical examination of a cholesterol-lowering agent used worldwide, the remarkable effect of improving a survival rate and preventing myocardial infarction is obtained even through the stenosis of a blood vessel hardly changes. This is because the agent stabilizes an atheroma as a tissue. In consideration of this fact, a method for examining the susceptibility of an atheroma to rupture (susceptibility to rupture) has been demanded. A conventional method such as X-ray CT, MRI, and angiography cannot carry out such an examination.
For example, in view of an accurate measurement on a blood vessel disease, conventional echocardiography M-mode just has a resolution of 1 mm. Similarly when the vibration of an aorta is determined as a displacement velocity by conventional Doppler method, conditions for accuracy are theoretically satisfied but the pulsation of a blood vessel greatly affects in reality. Thus, it is difficult to extract a small vibration superimposed to a relatively large amplitude. Hence, researchers including the inventor have developed a phased tracking method whereby a small vibration on a beating heart and a large blood vessel is remotely measured by ultrasound and an elasticity modulus of a blood vessel wall can be calculated on a given spot. Thus, it is possible to accurately diagnose the susceptibility of an atheroma to rupture (Reference Documents 1 to 5).
The following are reference documents:    1. Kanai H, Hasegawa H, Chubachi N, Koiwa Y, Tanaka M. Noninvasive evaluation of local myocardial thickening and its color-coded Imaging. IEEE transaction UFFC. 1997; 44: 752-768;    2. Hasegawa H, Kanai H, Hoshimiya N, Chubachi N, Koiwa Y. Accuracy evaluation in the measurement of a small change in the thickness of arterial walls and the measurement of elasticity of the human carotid artery. Jpn J Appl Phys 1998; 37: 3101-3105;    3. Kanai H, Koiwa Y, J. Zhang Real-time measurements of local myocardium motion and arterial wall thickening. IEEE-transaction UFFC. 1999; 46: 1229-1241;    4. Japanese Patent Laid-Open No. 10-5226; and    5. Japanese Patent Laid-Open No. 12-229078.
The phased tracking method will be schematically described below. The phased tracking method is a new bioinstrumentation for measuring a small vibration velocity on a cardiac wall and a blood vessel wall. This method makes it possible to accurately measure a vibration of 500 Hz or less and 0.01 mm and a change of 10 microns on a wall. With this method, for example, small velocities on a plurality of measurement points between the layer (or layers) in the arterial wall or on the wall of an arterial vessel are determined by ultrasonic Doppler method, and the small velocities on the measurement points are subjected to time quadrature, so that a time change in the positions of the measurement points can be calculated. Since a change in layer thickness can be determined by the time change in the positions of the measurement points, the elasticity modulus of the layer can be obtained, thereby estimating susceptibility to rupture.
Actually as shown in FIG. 17, an arterial intramural measurement point on an ultrasonic beam 91 is set at (i) and a measurement point with the subsequent depth is set at (i+1). Small vibration velocities vi(t) and vi+1(t) on the measurement points are determined and a difference between the small vibration velocities is subjected to time quadrature, so that a change Δh(t) in layer thickness between the measurement points (i) and (i+1) in the arterial wall is determined. Reference numeral 92 denotes a plaque.
      Δ                                h                    (        t        )              =            ∫              -        ∞            t                          {                                            v              i                                                  (              t              )                                -                                    v                              i                +                1                                                                (              t              )                                      }                          ⅆ        t
The simplest method for converting the change into an elasticity value for each layer in the arterial wall is performed as follows: a wall thickness is set at hd and a change in thickness is set at Δh at the lowest blood pressure where a wall thickness increases, a pulse pressure at a cuff pressure on brachial artery is set at ΔP, and a wall elasticity modulus is measured for each layer in the following manner.
Based on a thickness change (Δh) of each layer from the intima to the adventitia of a blood vessel, an elasticity value (En) of each small part (n) in a blood vessel wall atheroma is determined by the formula below.En=(ΔP/(Δh/hd)n)
With this phased tracking method, it is possible to measure an elasticity value for each layer along the depth direction in a blood vessel wall approximately every 0.75 mm to 0.075 mm on an ultrasonic beam, thereby displaying a tomogram based on the elasticity values.
In a clinical diagnosis using the phased tracking method, when an elasticity value is examined for each layer of a blood vessel wall, the elasticity value ranges from 100 to 2 MPa in a normal person. However, in the example of an atheroma, elasticity values are not evenly distributed. It is understood that fundamentally a physically soft portion is present in a thrombus and is covered with a hard portion. In addition, various patterns are present in the tomogram of an atheroma. For example, an extremely soft substance is exposed on the lumen of a blood vessel without continuity on a capsule of a hard surface, and a substance having a large elasticity value almost entirely covers a surface. Elasticity values in an atheroma are distributed from 0 to 4 MPa. Further, according to the examination results on the correspondence of a lipid-rich layer and a collage fiber in an extracted blood vessel and elasticity values in the phased tracking method, there is a probability that the tissue image of a collagen fiber covering an atheroma can be separately displayed from a tomogram of elasticity values, the tomogram being obtained in a noninvasive manner.
It is an object of the present invention to provide more specific information displayed in a tomogram and to identify the kind of living tissue such as a lipid-rich area, a thrombus area, an elastic fiber, a collagen fiber, and a calcified area in an ultrasonic diagnosis of a living tissue such as a lesion on a blood vessel.
It is another object of the present invention to identify the kind of living tissue such as a lipid-rich area, a thrombus area, an elastic fiber, a collagen fiber, and a calcified area by using a shear elasticity modulus and a shear viscosity in an ultrasonic diagnosis of a living tissue such as a lesion on a blood vessel.

Ultrasonic method and system for characterizing arterial tissue using known elasticity data


A sign is edge lit and illuminated by an array of light emitting diodes disposed along an edge of a light transmissive panel. A light diffusion surface, which can be formed by a series of serrations on the panel edge, disperses light from the discrete light emitting diodes in the array. A geometric figure, which can be text or graphics or both is formed on one face of the panel by grooves, which redirect diffused light so that an illuminated image, corresponding to the geometric figure, can be seen on the front of the panel. The grooves forming the figure and the light diffusion surface comprise parts of a one-piece panel, and the grooves and the light diffusion surface can be formed when the panel is injection molded.

1. Field of the Invention
This invention relates to signs illuminated by edge lighting. This invention also relates to the use of discrete light sources, such as light emitting diodes to illuminate a figure, so that only the figure is illuminated relative to the substrate on which the figure is formed.
2. Description of the Prior Art
Edge lit signs or signboards employing fluorescent lamps mounted adjacent one edge of a light transmissive panel have been employed to illuminate characters or figures on one face of the panel. Since a standard tubular fluorescent lamp emits a substantially uniform illumination along its entire length, it will uniformly illuminate a figure or a series of characters extending between opposite ends of the fluorescent lamp and presumably along substantially the entire length of the sign.
It has been recognized that light emitting diodes possess certain advantages over fluorescent lamps when used in edge lit illuminated signs. U.S. Pat. No. 6,341,440 is one example of the use of a series light emitting diodes or LED's disposed in a linear array in such a sign. Of course, standard LED's comprise discrete light sources when compared to a standard tubular fluorescent lamp. In order to illuminate a series of characters on a clear panel, it is therefore necessary to disperse or diffuse the light emitted by discrete LED's. U.S. Pat. No. 6,341,440 employs a light diffusion strip with a series of semicircular holes in which individual LED's are located. This diffusion strip is separate from the clear panel containing display characters or ornamental markings, and the diffusion strip is located adjacent one edge of the clear panel. According to this patent, the light is diffused so that the light emitted by individual LED's can enter an edge of the panel with a uniform hue, which presumably means that the light from individual LED's is diffused before entering the clear panel.
U.S. Pat. No. 6,615,520 discloses another example of an edge lit sign employing discrete LED's. In this version, LED's, fiber optic devices or halogen bulbs are fitted in tight fitting orifices along one edge of the panel. These orifices are described as tight fitting and well polished to allow for optimum transmission of light from the discrete light sources into the display board. Improved light transmission and efficiency is apparently of paramount importance. To diffuse the light, this device apparently employs reflective strips located in a receptacle in which the display board is mounted. The edges of the display board slope away from the centrally mounted LED's so that reflective walls of the panel insure little loss of light.
U.S. Pat. No. 6,481,130 is another example of an edge lit sign that employs a separate member to disperse the light form discrete LED's. This device employs both a reflector and a lens portion.
These devices, however, use a separate diffuser and light transmissive panel and appear to require precision in mounting the LED's relative to either the diffuser or the clear panel. These devices also appear to use a rather small number of LED's. For example, U.S. Pat. No. 6,341,440 shows three sets of red, blue and green LED's and U.S. Pat. No. 6,615,520 shows only three LED's. It would appear to follow that these devices must either employ relatively strong LED's or the displayed light intensity must be relatively weak. These devices also employ multiple components that appear to require precision in assembly.
The instant invention employs a light transmissive panel that includes both geometric figures or display characters and a diffusion surfaces that are integral part of the one-piece panel. This simplifies construction and provides an economical means for employing a relatively larger plurality of discrete light sources, such as LED's.


A rotary device for automatically dispensing and retracting a line, such as cutting filament for a vegetation trimmer, has a spool around which is wound a small coil of the line. The line has a cutting segment that extends radially from the spool. The cutting segment has a precise length that is automatically maintained by a balance of centrifugal force and aerodynamic drag. The rotary device also has additional storage capacity for the line. An additional supply of line for the rotary device beyond the small coil may be stored in many different forms while remaining ready for immediate deployment and use. Examples include extended storage loops of the line protruding from the spool, a second coil or reservoir of line located remotely from the spool, or a magazine of the line mounted to the spool.

The present invention relates in general to an improved rotary dispensing mechanism, and in particular to an improved rotary mechanism for automatically dispensing and retracting a cord-like element. Still more particularly, the present invention relates to an automated rotary mechanism for dispensing and retracting a cord-like element from a reservoir thereof.
Flexible line vegetation trimmers are known in the art, and are generally comprised of a long handle or rod having a cutting head at one end. The cutting head contains a spool of cutting line, similar to fishing line (polymeric monofilament), and a rotary device which causes the free end of the line to move in a circular fashion at high speed. When the cutting head is placed near overgrown vegetation, the spinning line hits the stalks or leaves and effectively cuts them away from the remainder of the plant. Flexible line vegetation trimmers have grown into a world-wide industry with annual sales exceeding a billion dollars.
One problem that has persisted with the use of flexible line trimmers (also referred to as rotary flails), is the dispensing of the cutting line from the spool. This line is typically constructed of a polymeric material that is relatively tough and durable but, after repeated use as a vegetation trimmer (or misuse on inappropriate surfaces), the line will break near the distal end, i.e., shortening the effective length of the line, and thus requiring replacement of the line, or extension of further line material from the spool.
In the prior art, there are four basic kinds of cutting heads: manual exchange; manual reel; semi-manual reel; and automatic reel. A manual exchange cutting head holds multiple lines which are not adjustable, but are instead completely removed and replaced when they get too short. The trimmer (rotary motor) must be stopped for replacement, and the stub ends are wasted. Additional material forming the mounting bracket for the lines is also discarded.
The reel types, whether manual, semi-automatic, or automatic, have a reel within a housing, and new line is delivered by releasing (rotating) this reel. With the manual reel type, the rotary motor must be stopped so the reel can be manually unlocked to extend new line. With the semi-automatic, feeding of new line is triggered by a hand lever or by bumping the cutting head on the ground. Manual and semi-automatic require the operator to monitor the line and decide when to take action. Another type of feeding device uses a mechanism which extends a length of line every time the rotary motor is slowed from a high operating speed.
The automatic reel types are equipped with a sensing device to monitor the line and activate a reel release or indexing mechanism to feed more line. A cycle of gradual decreases and sudden jumps in line length are an inherent feature because of the threshold for triggering the reel mechanism. Sudden jumps in line length cause wasted line, explaining the lack of commercial success of these types of cutting heads. Multiple independent automatic lines have been very impractical because of the complicated mechanisms involved. Today, almost all trimmers sold are equipped with bump feeds.
Reloading bump feeds is complicated and time-consuming. Casual users especially dislike the details of loading the line spool onto the cutting head. Even for those devices in which no disassembly or tools are required, it is still necessary to (i) bring the spool into loading alignment, (ii) insert the first cutting line into a loading hole, (iii) anchor the cutting line to the spool, (iv) repeat steps two and three for a second line, then (v) rotate the spool to draw the lines into the housing and wind them onto the spool. Bump feeds also have a tendency to jam. The bump button can get surrounded with mud, wet grass, or other bits of debris, and prevent proper dispensing of the line. Moreover, during feeding of a bump-type device, the head is subjected to sharp shocks which tend to jam the line in the coil and prevent smooth feeding of line. Clearing a jammed coil or bump button is time-consuming and can be further frustrating.
To date, rotary dispensing mechanism such as vegetation trimmers have only been capable of increasing the length of their consumable filament lines relative to the spool. Other than providing a sharp blade at a fixed distance from the spool for chopping off excess line, no vegetation trimmer is capable of reducing the length of the line without cutting the line and wasting the cut portion.
In addition, all vegetation trimmers dispense additional filament in such a manner that the cutting radius of the trimmer constantly varies. It has never been possible to maintain the filament at an ideal cutting length without cycling between upper and lower cutting radius bounds. This problem exists for all three types of filament feeding mechanisms (manual feed, semi-automatic feed, and automatic feed). Before additional filament is released, the cutting radius must be worn down or consumed to trigger a xe2x80x9crelease eventxe2x80x9d (e.g., the operator actuates a mechanism, or the machine deploys more line). Moreover, when a release event does occur, almost all such rotary devices release an excessive length of filament that must be wastefully cut off to a proper length before the device can be effectively used again. Furthermore, rotary devices that utilize automated filament feeders typically require elaborate mechanisms with complex moving parts that are more expensive and less reliable than their primitive counterparts.
Even relatively simple, automatic feeding mechanisms, such as the one disclosed in U.S. Pat. No. 4,569,134, require a significant reduction in the cutting radius before the mechanism will deploy additional filament. These devices typically have a spool with a pair of sidewalls that are joined at their peripheries by guide support rods. A length of filament is coiled on the spool for vegetation trimming. The free end of the filament (three free ends are shown) bends around one of the guide support rods before extending radially away from the spool. The guide support rods prevent the filament from being inadvertently released and are needed to prevent unintended release of the filament both during operation and during non-operation.
During operation, a substantial portion of the filament must be consumed before additional filament is released. Unfortunately, the cutting radius of the vegetation trimmer is concomitantly reduced, thereby reducing the effectiveness of the trimmer. only when the shortened filament approaches its supporting rod does the filament release from the rod to increase the cutting radius once again. Thus, this trimmer operates in a cycle with discrete unwinding events, triggered by a significant shortening of the extended line. The cutting radius fluctuates between upper and lower bounds, gradually decreasing, then suddenly increasing when a discrete unwinding event is triggered.
In light of the foregoing, it would be desirable to devise an improved method of dispensing cutting line in a vegetation trimmer. It would be particularly advantageous if the method utilized a cutting head that would rarely, if ever, jam nor need maintenance or adjustment, was easily reloaded without tools or requiring disassembly, and was capable of dispensing the cutting line from a reservoir.
A rotary device for automatically dispensing and retracting a line, such as cutting filament for a vegetation trimmer, has a spool around which is wound a small coil of the line. The line has a cutting segment that extends radially from the spool. The cutting segment has a precise length that is automatically maintained by a balance of centrifugal force and aerodynamic drag. The rotary device also has additional storage capacity for the line. An additional supply of line for the rotary device beyond the small coil may be stored in many different forms while remaining ready for immediate deployment and use. Examples include extended storage loops of the line protruding from the spool, a second coil or reservoir of line located remotely from the spool, or a magazine of the line mounted to the spool.
Accordingly, it is an object of the present invention to provide an improved rotary dispensing mechanism.
It is an additional object of the present invention to provide an improved rotary mechanism for automatically dispensing and retracting a cord-like element.
Still another object of the present invention is to provide an automated rotary mechanism for dispensing and retracting a cord-like element from a reservoir thereof.
The foregoing and other objects and advantages of the present invention will be apparent to those skilled in the art, in view of the following detailed description of the preferred embodiment of the present invention, taken in conjunction with the appended claims and the accompanying drawings.

Rotary device for automatically deploying and retracting a cord-like element from a storage device


A tapered rotary feed valve is manufactured or refurbished for use in feeding materials into a high temperature environment, so as to reduce the time and expense of break-in operation, by shaping the tapered bore of the valve body at ambient temperature to have greater clearance around the rotor in a sector of the valve body that is cooler when the valve is at stable operating temperature. As a result, when the valve first reaches operating temperature after being manufactured or refurbished the rotor and the bore of the valve body nearly fit and can quickly wear in to fit each other closely.

Rotary material handling valves such as those disclosed, for example, in Starrett U.S. Pat. No. 3,273,758 and Starrett U.S. Pat. No. 3,750,902, are used for transferring particulate material into a pressurized environment at raised temperature. For example, such valves are used for feeding raw materials such as pulp wood chips and sawdust into a container of hot pulping liquor in the process of manufacturing paper. On a receiving side of such a valve, the chips are fed to the valve at temperatures near ambient atmospheric temperatures and at atmospheric pressure. The valves must deliver those materials into a container where temperatures and pressures are elevated significantly. It is desirable to feed the raw materials into the processing container continuously at high volume rates, but with a minimum loss of pressure from within the processing container.
Valves of the type with which this disclosure is concerned require close clearances between a tapered rotor and a surrounding housing when the valve is fully warmed up and operating in a stabilized continuously operating condition. Such valves may have rotors varying in diameter from 35 inches to over 40 inches along the length of the rotor.
Previous practice in the use of such rotary valves has included placement of the axis of rotation of the rotor of the valve in an eccentric location with respect to the tapered bore in the surrounding body of the valve when the valve is assembled at normal atmospheric temperature, and the valve has thereafter been operated with frequent adjustment during a break-in period during which the rotor and the opposing surfaces of the housing have worn each other until the rotor has become seated around the entire periphery of the housing with the desired close clearance so as to minimize leakage of gas under pressure from the processing container into which raw material is being fed by the valve.
The wear-in period includes axial movement of the rotor with respect to the body by means of an adjustable thrust bearing arrangement, and a considerable amount of material has to be worn away from the mating surfaces of the rotor and housing before the desired close fit is attained in a tapered rotary feed valve manufactured in accordance with Starrett U.S. Pat. No. 3,750,902. Since the rotor has to be moved axially into a position in contact with the housing, so that wear will occur where necessary, the power required to rotate the rotor during break-in is higher than is usual once a valve has been broken in, and leakage of pressurized gas or steam from the processing container occurs, wasting heat, during the break-in period.
The required wear-in period for such valves has been many hours long, often as much as two weeks.
As stated in Starrett U.S. Pat. No. 3,750,902, it has commonly been believed that an offset of the axis of rotation of the rotor was desired to accommodate elastic flexure of the rotor shaft and to accommodate take-up of clearances in the bearings themselves, so that the rotor would essentially be centered in the housing, with minimal clearance between mating surfaces of the rotor and housing, during operation of the valve. Excessive leakage into the end-bells had resulted from the misfit of the rotor in the valve body with the rotor bearings centered. The real reason the bottom sector was not sealing fast enough was the misfit at the rotor-to-body seal areas in the lower sector in a new valve. This was a result of the thermal profile of the body in a stabilized hot valve. The downwardly eccentric displacement of the rotor had the effect of reducing the amount of plugging in the ends, etcetera, long enough for the rotor to wear-in until the rotor was effectively "lapped" in to fit the bore at hot equilibrium. It should be noted, the problem of leakage was particularly problematical when users started using sawdust for furnish in the early 1970's.
The downwardly eccentric adjustment of the rotor axis caused the lower sector of the bore to wear-in to a close fit first. Quickly establishing a seal in the lower sector was paramount, because without it fines—especially sawdust—escaped past the seal at each end of the rotor in the bottom sector, causing end-bell plugging, excessive gas bypass into the inlet, and troublesome startups.
In the valve manufacturer's manuals, regrind was advised when the user finds the valve liner thickness varies 0.020″. The user would find this condition every time the unit was taken apart, as a result of the wear during break-in because of the prescribed downwardly eccentric rotor shaft location.
Two primary causes may contribute to change in shape in a high pressure rotary valve: thermal profile variations and elastic deflection because of pressure differential across the valve. Both are related to properties of the materials of which the rotor and the housing are manufactured. It has been calculated that the strain of the housing, or body, of the valve because of pressure differential would be about seven millionths (0.000007) of an inch (insignificant for a Bauer rotary valve, the type of valve disclosed in the Starrett patents), far less than the offset, eccentrically downward placement of the axis of rotation of the rotors according to the manufacturer's recommendations for those valves.
As for possible deflection of the shaft, bending in response to pressure between the outlet and inlet sides of the valve, based on 150 pounds per square inch pressure differential across the valve, the maximum deflection in bending, determined by a finite elemental analysis of the rotor, is also much less than the recommended downward eccentric offset location of the shaft. Elastic deflection therefore does not require the use of an eccentric offset location of the axis of rotation of the rotor.
The real issue is one of thermal profiles in the materials of the housing and rotor to account for the shape and size of the housing and rotor in a condition of equilibrium once the valve has been in operation long enough to achieve its operating temperature during continuous operation.
What is desired, then, is an improved way to manufacture or overhaul and assemble such a rotary valve so that the time required for break-in is shorter and the valve is operable thereafter for a longer time.
In operation of a rotary feed valve, uniform heating of the rotor occurs because the rotor rotates over the heat source, the pulp digester or other container with which the rotary valve is used, because of the higher temperature of the materials under pressure within the container on which the valve is mounted. The housing, or body, of the high pressure rotary valve is bolted to the container, which is the heat source, and is therefore subject to a thermal gradient from the bottom of the valve toward its top. Additionally, as the temperature of the rotor increases, its initial taper angle increases, because the large end of the rotor, with a larger radius, expands by a larger distance than does the smaller end of the rotor.
Because the upper portion of the body of the valve never is heated to as high a temperature as the bottom portion, the internal radius of the body does not increase as much in the upper sector of its bore as in the lower sector.
Initial operation of such a high pressure rotary valve when new or refurbished to factory specifications requires the body bore to be worn into a shape matching that of the rotor, so that the valve minimizes pressure loss when it has reached its equilibrium temperature distribution after operating for a long enough time.
It takes about eight hours for a tapered high pressure rotary feed valve of the size used in pulp processing to reach thermal equilibrium under continuous operation. Ideally, when starting such a valve one would give the valve at least three to four hours in which to stabilize. With a shorter time allowed for starting operation of the valve the thermal gradient between the top and bottom of the valve becomes larger, and the distortion of the shape as a result of unequal temperatures is greater.
The rotor stays round; it wants to seal all around on its circumference, on each end. At the same time the upper sector of the body bore, frustoconical when shaped at ambient temperature, takes on an oval section profile when the valve body reaches thermal equilibrium in operation. The non-uniform temperature profile thus prevented the rotor from sealing at the seal edges in the lower sector, because the rotor grows, radially, from heating—more than the surrounding body—and had to be pulled back axially to the last contact position, which is in the cooler upper sector of the body. Pulling the rotor back axially (thereby increasing the rotor-to-body clearance at the bottom) to compensate would make the leakage into the end-bell cavities worse.
The rotor contact first taking place at the top of the bore apparently led Bauer to surmise that the rotor had been deflected and at least to determine the rotor needed to be moved into the lower sector to mitigate the leakage (at the bottom) into the end-bell cavities, during the break-in or wear-in period.
In accordance with the present disclosure, the rotor axis of rotation should be located on the primary bore axis. As defined in the claims which form a part of this disclosure, the interior mating surfaces of the housing, or body, of such a rotary valve should be shaped when at normal ambient temperature during manufacture or overhaul to have a non-circular internal section shape that will become circular when the valve reaches its normal stabilized operating temperature profile, so that the rotor will fit the body with relatively little break-in wear being needed.
The body or housing can thus be prepared so that a minimum amount of break-in time is required for the rotor and body bore to wear in to fit against each other when the valve has reached equilibrium at its operating temperature and temperature distribution.
In general terms, this is accomplished by shaping the interior surfaces of the body bore of the housing, with the housing at ambient temperature, so that with the rotor located with its axis of rotation in the designed location the rotor clearance in the upper half or sector of the bore is greater than that in the lower sector of the bore, with the difference in clearance being equal to the difference in thermal expansion of the bore in the top sector or half of the body, relative to the thermal expansion of the bore in the bottom sector or half as a result of the different temperature increases of the different portions of the valve body between ambient temperature and operating temperature of the valve.
In one embodiment of the method disclosed herein a valve body may be prepared by first cutting or grinding the body to form an initial bore with interior surfaces symmetrical about the axis of rotation of the rotor, and then removing additional material from the interior of the valve body to form an enlargement of the initial interior bore, of the same size and shape as the initial bore, centered about an axis parallel with the axis of rotation of the rotor but displaced toward the inlet side of the body by a distance related to the difference in temperatures between the inlet side and outlet side of the valve in stabilized operation.
As a further refined variation, the bore of the body of the valve can be adjusted to a slightly different cone angle to account for the slightly greater enlargement of the larger end of the rotor as it is heated to operating temperature.
The foregoing and other features of the invention will be more readily understood upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings.

Tapered high pressure rotary feed valves


An enhanced hybrid duplexing technology (EDHT)-based communication method including dividing a cell prescribed by a transmission power of the base station into at least two logical areas, dividing the system frequency band into at least two subbands, and communicating in different duplexing modes using at least one of the subbands according to a position of the terminal within the cell. According to the method, a flexible resource management is possible according to the communication environment by dividing an entire system band into at least two subbands, differentiating the bandwidths of the subbands and the duplexing techniques, and selecting and allocating the resources of the subbands according to the position of the terminal within the cell.

1. Field of the Invention
The present invention relates generally to a wireless communication system, and more particularly to a communication method for improving the flexibility of resource allocation and maximizing the system performance through an enhanced hybrid duplexing technology (EHDT) that selectively applies diverse duplexing modes.
2. Description of the Related Art
The next-generation wireless communication system, including the 3rd generation mobile communications, attempts simultaneous support of multimedia services of diverse traffic characteristics such as broadcastings and real-time video conferences in addition to voice services. Accordingly, in order to efficiently provide services of such diverse characteristics, a duplexing technique in consideration of asymmetry and continuity of uplink/downlink according to the service characteristics is required.
Generally, the duplexing technique is classified into a time division duplexing (TDD) and a frequency division duplexing (FDD). TDD is a technique for implementing bidirectional communication by dividing the same frequency band into time slots and alternately switching transmission and reception slots. An FDD is a technique for implementing bidirectional communication by dividing a given frequency band into transmission and reception bands.
In a TDD-based communication system, a base station can allocate a part or all of usable time slots to a terminal, and through this variable allocation of the time slots, asymmetric communication is possible. However, in TDD, if the radius of a cell is extended, a protection section between the transmission/reception time slots is increased due to a round trip delay and this causes the transmission efficiency to be lowered. Accordingly, it is improper to use TDD in a communication environment in which the cell has a large radius such as a macro cell.
Additionally, in TDD, the asymmetric ratios of the respective cells are not equal to each other in a multi-cell environment, and thus severe frequency interference occurs between terminals located on the border of an adjacent cell.
In an FDD-based communication system, the frequency bands for transmission and reception are separated from each other, and thus no time delay for the transmission or reception occurs. Accordingly, no round trip delay due to the time delay occurs. Therefore, FDD is suitable to the cell environment in which the cell has a large radius such as the macro cell.
However, in FDD, the transmission frequency band and the reception frequency band are fixed, which it is not proper for duplexing the asymmetric transmission.
Therefore, research into duplexing techniques that mix the two kinds of duplexing techniques in consideration of the diverse next-generation communication environments and traffic characteristics is being actively progressed.
FIG. 1 illustrates a conventional duplexing technique based on a dual band. Referring to FIG. 1, a base station performs the same-period transmission/reception mode conversion with respect to two frequency band channels, i.e., wide-band and narrow-band channels, and terminals connected to the base station operate in a reverse mode to the base station and are allocated with resources for reception and transmission on the two frequency band channels without any overlap. That is, with respect to the wide-band channel 101a of the transmission mode section of the base station, terminal #1 and terminal #2 each occupy half of the wide-band channel 101a as their reception mode sections, and terminal #3 and terminal #4 are allocated with parts of the narrow-band channel 103A of the base station transmission mode section as their reception mode sections 103A-2 and 103A-1, respectively. Additionally, with respect to the wide-band channel 101b of the reception mode section of the base station, terminal #1 and terminal #4 occupy parts of the wide-band channel 101b as their transmission mode sections 101b-1 and 101b-2, and terminal #2 and terminal #3 occupy parts of the narrow-band channel 103B of the base station reception mode section as their transmission mode sections 103B-2 and 103B-1, respectively.
Although the duplexing technique based on the dual band as described above enables flexible resource allocation possible by combining and allocating the wide-band channel and the narrow-band channel, it is difficult to expect the link continuity inherent in FDD because the transmission/reception mode conversions of the wide-band channel and the narrow-band channel are simultaneously performed.
FIG. 2 illustrates a duplexing technique based on band switching. According to this duplexing technique based on a band switching, an uplink and a downlink are periodically repeated for a specified period (Tsec) within one band, and thus the other band is simultaneously used as the uplink and downlink with the channel conversion characteristic of TDD. However, when duplexing based on the band switching, because the same band channels are used, the flexibility of resource allocation is lowered and it is difficult to implement an asymmetric transmission by the periodic channel conversion.

Cellular communication method based on enhanced hybrid duplexing technology


A constant-current power supply circuit includes a bias circuit (20); first and second transistors (11 and 12); an output terminal (OUT); a bias voltage defining circuit (30 & 40); and a compensator (50 or 60). The bias circuit (20) generates a first bias voltage (Vb1). The first transistor (11) supplies a first current (I.sub.1) in response to the first bias voltage (Vb1), supplied from the bias circuit (20). The first current is outputted from an output terminal (OUT). The second transistor (12) is connected between the first transistor (11) and the output terminal (OUT) and is operated in response to a second bias voltage (Vb2). The bias voltage defining circuit (30 & 40) defines the second bias voltage (Vb2). The compensator (50 or 60) is connected to the bias defining circuit (30 & 40) to perform temperature compensation.

A constant-current power supply is capable of maintaining a preset current through a variable load resistance. A conventional constant-current power supply circuit is described in Japanese Laying Open S63-265315. The reference discloses plural constant-current power supply circuits connected to a common power supply line. Each constant-current power supply circuit is provided with P-channel field effect transistors (hereafter referred to as PMOS) and N-channel effect transistors (hereafter referred to as NMOS). Sources of PMOS and NMOS are mutually connected, while the drain of the NMOS being connected to the power supply line which supplies the power voltage. It is constructed to output constant current (constant current) from the drain of the PMOS.
Each NMOS gate is supplied with common bias power generated by a bias circuit based on the power voltage, and each of the PMOS gates is supplied with bias voltage generated by the bias circuit based on the power voltage, independently from each PMOS.
As stated in the above reference, the NMOS, installed between the PMOS and the power supply line, corrects any power voltage variation generated by the power supply line resistance in each constant-current power supply circuit. Therefore, variation of the constant-current output supplied from each constant-current power supply circuit is eliminated.
According the above-described conventional constant-current power supply circuit, however, the bias voltage supplied to the NMOS and PMOS varies due to temperature variations in the power voltage source. Therefore, the constant current output supplied from the PMOS will also vary in response to the temperature.

Constant-current power supply circuit and digital/analog converter using the same


A switching apparatus, system, and method configured to operate at least a dual line downhole tool via a single pressure source are provided. The switching apparatus may comprise a housing configured to contain a switching piston actuated by a fluid pressure source. The apparatus may further contain a switching valve comprising a first and second coupling passageway coupled to a switching valve housing comprising four ports. The switching piston may actuate the switching valve, alternating the coupling between a first configuration in which the four ports are communicatively coupled into two sets of ports and a second configuration in which the four ports are communicatively coupled into an alternate two sets of ports. The first configuration may configure the fluid pressure source to actuate the downhole tool in a first manner and the second configuration may configure the fluid pressure source to actuate the downhole tool in a second manner.

1. Field of the Invention
The present invention relates generally to the control of downhole tools, and more particularly to single control line actuation of downhole tools.
2. Description of the Related Art
The following descriptions and examples are not admitted to be prior art by virtue of their inclusion in this section.
Many hydraulically actuated downhole tools require two dedicated control lines to apply a pressure differential across a piston seal in order to translate an actuating device such as a mandrel or other similar component. This actuating device may be coupled or attached to a valve, such as a barrier or sliding sleeve valve, among others, in addition to other downhole tools or devices. For example, the valve may separate two zones of a formation or control the flow of fluid from the formation into the production tubing. However, the use of two individual control lines may add to the overall complexity of a downhole completion and occupy an increasingly limited space in a downhole environment. In addition, two control lines may raise the risk that one or both of the control lines is damaged during run in and/or operation. If there is a threshold level of pressure existing in the control lines, a leak in one control line may cause an inadvertent actuation of a downhole device as the threshold pressure from the other line is applied across the piston. Such a situation may significantly increase the risk of a catastrophic event, such as the unintentional discharge of hydrocarbons into the environment resulting from the inadvertent opening a safety valve for example. A single control line may provide increased levels of efficiency and reliability along with decreased amounts of complexity and space utilization.

Method for controlling a downhole tool with a linearly actuated hydraulic switch


The present application provides a combustor for use with a gas turbine engine. The combustor may include a head end with a non-circular configuration, a number of fuel nozzles positioned about the head end, and a transition piece extending downstream of the head end.

Generally described, industrial gas turbine combustors are designed with a number of discrete combustion chambers or "cans" arranged in an array around the circumference of a first stage of a turbine. The combustor cans ignite a fuel/air mixture such that the resultant hot combustion gases drive a downstream turbine. The major components of an industrial gas turbine can-type combustor may include a cylindrical or cone-shaped sheet metal liner engaging the round head end of the combustor and a sheet metal transition piece that transitions the flow of hot combustion gases from the round cross-section of the liner to an arc-shaped inlet to a first stage of the turbine. These and other components positioned about the hot gas path may be cooled by a flow of air through an impingement sleeve and the like.
Efficient operation of a can combustor thus requires efficient cooling, efficient transition of the flow of hot combustion gases from the combustor to the first stage of the turbine with low pressure losses, and efficiency in other types of operational parameters. Can combustor design thus seeks to optimize these parameters for increase output and overall performance.


A CT scanner or other medical diagnostic imager (A) generates data which is reconstructed (B) into a three-dimensional image representation that is stored in an image memory (C). Points on a surface (10) of a selected subregion, such as the surface of an internal organ, in the three-dimensional image representation are determined (12) which are visible from and correspond to pixels on a viewing plane (14). For each viewable point on the surface, a mean variation along an x, y, and z-coordinate system with its origin at the surface point in question is determined (20). A covariance matrix whose matrix elements along the diagonal are indicative of a rate of variance along each axis and whose other matrix values are indicative of a rate of variance relative to pairs of axes is defined (20). A rate of most rapid change through the 3D data is determined (22), by eigenvalue decomposition (24) of the covariance matrix. A vector along the rate of most rapid change is normalized (26). Gray scale shading for a pixel of a man-readable display (E) corresponding to the surface point is determined (28). In the preferred embodiment, the gray scale shading is proportional to the cosine of the angle between the normalized vector in a direction of most rapid gray scale change and a light source vector. In this manner, the surface normal to a surface at the points which correspond to each pixel of an image display are efficiently determined and provided with an appropriate gray scale value to make the two-dimensional image display appear as if it were three-dimensional.

The present invention relates to the image display arts. It finds particular application in conjunction with providing surface shading for 3-D presentations of diagnostic medical images on video monitors and will be described with particular reference thereto. However, it is to be appreciated that the invention finds application in other areas, including providing surface shading in other 3-D displays, determining normals to surfaces, interfaces, or contours in computer or mathematical data, and the like.
Heretofore, three-dimensional appearing images of internal organs have been projected from CT and other medial diagnostic data. That is, shading is added to a video or other two-dimensional display to give the effect of depth in the direction perpendicular to the screen. Commonly, a planar array of pixels or viewing plane is defined relative to the three-dimensional array of the medical diagnostic data. Typically, the three-dimensional array of diagnostic data is characterized by gray scale values corresponding to each of a three-dimensional rectangular array of data points or voxels. The organ of which a three-dimensional appearing display is to be generated is typically buried within the data. Each pixel of the viewing or image plane is projected orthogonal to the viewing plane into the data. Each time the ray crosses into another voxel, the voxel gray scale value is compared with threshold gray scale values for the organ of interest. From the depth at which each ray intersects the organ and whether a ray intersects the organ at all, a map is generated of the surface contour of the organ when viewed from the viewing plane. Of course, because each of the voxels has a similar gray scale level, displaying this image would look more like a silhouette than a three-dimensional display.
To give meaning to the surface contour, shading is added to the exposed surfaces of the image. Several methods have been developed in the prior art for adding shading to medical and other three-dimensional images. These methods include depth shading, depth gradient shading, gray scale level gradient shading, and rendering with polygonal shapes. In depth shading, the simplest of these methods, the gray scale value of each voxel is displayed in inverse proportion to the distance from the viewing plane to the voxel at which the orthogonal ray intersected the organ of interest. The depth shading technique produces almost no fine detail on the surface, hence, has limited diagnostic value.
The other three methods each attempt to estimate the direction of the organ surface relative to the viewing plane orthogonal rays at each point of intersection. In depth gradient shading, an estimate of the surface inclination relative to the orthogonal ray from the viewing plane is determined by gradient operators on the depth image. Gray scale shading is added to each voxel in accordance with this angle of inclination. While the inclusion of surface inclination for shading improves the appearance of the images, gradient operators provide a relatively coarse quantization of the surface angles. That is, the surface normals estimated by this technique are not accurate which degrades the resultant image quality.
The image quality can be improved using the gray scale gradient shading techniques. In this technique, the gradient of the gray scale level along the surface is used to estimate the surface normal, rather than using depth or angle of the voxel surface. The estimation of the gradient in the voxel data can be performed using a number of operators of varying size. The high dynamic range of gray scale levels within a small spacial neighborhood produces superior image quality. However, this technique is unable to handle thin structures and it is inaccurate when estimating the surface normal in noisy images, i.e. when the signal to noise ratio is low.
In the polygonal shaped rendering technique, the data is pre-processed and the surface approximated with a set of polygons, e.g. triangles. The surface normal is readily computed as each polygon as being defined. In the Cuberille method, each surface voxel is treated as a small cube. The faces of the cube are output as small squares projected on the viewing screen. These polygon techniques have problems handling branching structures and tend to eliminate fine detail, especially when the polygons are large compared in size with a voxel.
The present invention contemplates a new and improved technique for determining surface normals.

Accurate estimation of surface normals in 3-D data sets


A down-hole tool guide is disclosed for deflecting various down-hole tools having a tendency to hang or bind in uncased bore holes. The down-hole tool guide or ball guide assembly, being adaptive to the down-hole tools, extends forwardly there from and includes an eccentric rotatable ball and high-pressure jets. In cases where the guide is used to guide casing, the ball guide assembly is constructed from a drillable material thereby allowing the hole bore to be extended beyond the last set casing depth without side deviation from the original bore.

Generally hole-opening operations down-hole involve the use of a hole-opening tool to enlarge a well bore. Such tools include a tool body configured for attachment at an upper end to a rotary drill string or the like and a lower end connected to a bull nose or radial member used for positioning and guiding the tool into and though the well bore to be enlarged. The tool further includes plurality of vertically extending slots each of which is configured to receive a removable cutter assembly adapted for rotation and retention therein. As the tool rotates, the cutters also rotate as a result of contact with the walls of the borehole, thus enlarging the bore to the size of the major diameter of the cutters. The bull nose serves as a guide through the previously drilled borehole. However, the previously drilled bore hole is by no means a well defined smooth or straight bore and often contains numerous cavities due to the differences in materials in the formation. It has been observed that the bull nose tip attached to the hole opening tool often jams into the crevices and sharp formations, especially in deviated holes approaching the horizontal, causing severe damage to the tool requiring retrieval and replacement of the hole opening tool. Therefore, a more reactive guide is needed to deflect the hole-opening tool around pits and in-penitratable projections.
In addition, it has also been observed that significant problems arise when attempting to insert and set casing in a bored hole. Intermediate casings are equipped with a flared flange at the lower end, extending outward between the casing outside diameter and the hole bore size, thus forming the base of the casing annulus. This flared or flanged casing must be negotiated though the bored hole and often becomes wedged or jammed in the crevices or pockets, discussed above, causing withdrawal and rotation of the casing in order to get past the obstruction. Therefore, a more reactive guide is needed to defect the casing flange around the pits and crevices. The following description of a down-hole guide tool has proved effective in solving the above-described problems.

Hole opener and drillable casing guide and methods of use


The present disclosure provides an automated scheme for generating and verifying a three-dimensional (3D) representation of a target space. In one embodiment, the automatic generation of a 3D representation of a target space includes receiving target space data from one or more mobile data capture devices and generating a local point cloud from the target space data. In one embodiment, the local point cloud is incorporated into a master point cloud. In one embodiment, a polygon mesh is generated using the master point cloud and the polygon mesh is rendered, using a plurality of visual images captured from the target space, which generates the 3D representation. In one embodiment, the automatic verification includes comparing a portion of the 3D representation with a portion of an approved layout, and identifying one or more discrepancies between the portion of the 3D representation and the portion of the approved layout.

In today's competitive retail market, retail stores often rely on product placement to maximize product sales. For example, marketing analytics may indicate that a product's sales should increase when that product is placed next to another product (e.g., sales of peanut butter and jelly increase when placed next to bread), or a retail store and a product manufacturer may agree to have a particular product temporarily displayed in a special display case in order to attract customer attention and increase product sales. A central administrative office of a retail store often invests a great deal of resources (e.g., time, money) into developing product placement in the form of a planogram, which is implemented in one or more retail stores. However, product placement in a retail store may not accurately follow the planogram, which may result in missed product sales opportunities.
While the present disclosure is susceptible to various modifications and alternative forms, specific embodiments of the present disclosure are provided as examples in the drawings and detailed description. It should be understood that the drawings and detailed description are not intended to limit the present disclosure to the particular form disclosed. Instead, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.

Automated generation of a three-dimensional space representation and planogram verification