An enhanced interleave type error correction method is provided in which decoding of an enhanced interleave block is done. Subsequently the decoding may be done by decoding the estimated codewords multiple times using a single error correction code. In addition, a decoder and a digital communication system for implementing the enhanced interleave type error correction method are provided.

Digital communication systems are designed to transmit user data in some digitized form from a source to a destination The means coupling the source and destination can be a simple conducting wire, a global satellite system or a data storage system, such as a magnetic disk drive or an optical compact disk. The coupling means is often generalized as a channel between the source and destination.
All channels occasionally introduce noise and distortion into the signals they carry. The noise and the distortion change the transmitted signal and thus can create errors at the output. To protect the information in the transmitted signals as they pass through the channel, error correction systems have been developed that add additional information to the digital signal to be transmitted so that the original signal may be recovered even if the channel introduces errors.
An error correction system consists of an encoder and a decoder, both based on an error correction code (ECC). The encoder, used at the information source, computes a certain amount of parity check symbols from the user data to be transmitted or stored. The encoding is done by applying an encoding rule to the user data. Then, the user data and the parity check symbols, together known as codewords, are all transmitted or stored through the channel and may be corrupted by noises and distortions. At the destination, a detector is used to estimate the codewords transmitted or stored through the channel. The decoder at the destination takes in the estimations of the codewords and attempts to recover the original user data according to the encoding rule.
Because of the noises and distortions in the channel, the detector occasionally makes incorrect estimations. Consequently, the input to the decoder has errors. Sometimes the detector is not able to make a clear estimation from its input. In this case, the detector can flag some positions as erasures in the estimated codeword.
The error correction capability of a particular ECC is determined by its minimum Hamming distance, usually denoted as d. For such a code, there exist decoding algorithms that can correct t errors and recover s erasures as long as d>2t+s. In order to correct errors, the decoder tries to figure out whether there is any errors in the estimation and if there is, determine the position and the value of the errors and correct them. To recover erasures, the decoder makes decisions on erasures at known positions based on the code structure. Sometimes the decoder can not find a valid codeword, subject to the encoding rule, because of excessive errors or erasures in its input. In this case, the decoder may declare a failure in decoding.
In many digital communication systems, the data is processed in blocks independent of each other rather than individual symbols. For example, in some communication networks, data is transmitted and received in packets. In data storage devices, data is stored or retrieved in sectors. For the same amount of redundancy, maximum ECC protection of such blocks of data can be achieved by encoding every block of data into one single codeword. However, the encoder and decoder for such codes are usually too complicated to implement because the code required is too long. Thus, several shorter codewords are used to encode the whole block. In channels where burst error is a significant source of error, interleaving is used to spread a single long burst error to multiple codewords so that the error correction capability of several codewords can be combined to combat burst errors.
An example of an interleaving error correction system is found in the system used in storing and retrieving data from some magnetic storage devices. It is very important for the error correction system in these devices to be able to recover data suffering from long burst errors, which may result from defects in the storage media.
In a typical situation, user data is stored and retrieved in sectors. Each sector has 512 bytes of user data. The ECC of choice is a Reed-Solomon code over finite field 28, whose symbol happens to be an 8-bit byte. The maximum length of a codeword of this code is 255 bytes, including the parity check symbols. Therefore, at least three codewords are needed to protect one sector. If three codewords are used, there are 171 bytes of user symbols in each codeword. By appending 4 parity check bytes to each 171-byte group, a code with minimum Hamming distance of 5 can be constructed. Then, storing, one after the other, a corresponding byte from each codeword and doing so repeatedly until all the bytes have been transmitted. Thus, the complete set of user bytes and ECC bytes for any one codeword can be found by sampling every third byte of the interleaved block. This is often referred to as a three-way bytewise interleave. The series of interleaved codewords is transmitted through the channel where it is occasionally corrupted by burst errors. The burst errors usually affect two or more consecutive bits and, because of the interleaving, corrupt two or more codewords.
Interleaving reduces the effects of burst errors on the ECC encoded signal. Burst errors are short duration error events affecting one or more consecutive symbols. By ensuring that consecutive words in the ECC encoded signal are not from the same codeword, interleaving reduces the chance that a burst error will affect more than one symbol in a codeword. If ECC can typically only correct two user bytes per codeword, interleaving will reduce the chances that a burst error will exceed the maximum number of symbols that can be corrected.
After being retrieved from the channel, the detector decodes the interleaved transmitted sequences into estimations of the ECC encoded signal. If a single block suffers from one very long burst error or more than one burst, the ECC decoder may not be able to correct the corrupted data because more than the maximum number of symbols of ECC encoded data will be corrupted in a single ECC codeword. In general, the single burst error correction capability is limited to L×t0 symbols, where L is the number of codewords in the interleaved block and to is the random error correction capability of an individual codeword. The random error correction capability of an individual codeword can be determined by the particular ECC employed and the number of parity check blocks added to that codeword. It is well known in the art that decoders exist for typical ECCs that can be used to simultaneously correct errors at unknown positions and recovery erasures at known positions.
In some prior art systems, the number of parity check symbols to be added to each codeword is the same. When the interleaved block is decoded, if the decoder fails to decode any one of the codewords, the attempt to decode the whole block is considered a failure.
In other prior art systems, there is a first number of parity check blocks added to a selected codeword and there is a second number of parity check blocks that are added to the remaining codewords. In the latter prior art, a dual decoder system is implemented having two decoders with differing error correction codes, wherein each of the codes has a different error correction capability. The first decoder has a greater single burst error correction capability than the second decoder. During the encoding routine, parity check symbols are added to each codeword, but one codeword is selected from the number of codewords and more parity check symbol are added to the selected codeword. Thus, the selected codeword has a greater error correction capability than the other codewords. In relation, the first decoder allows correction of the errors in the selected codeword. When decoding the selected codeword and a correctable error is detected, the dual-decoder system assumes that errors exist in adjacent positions of the other codewords.
The adjacent positions to the correctable error positions of the first decoded codeword are identified as erasures in the other codewords and then used in the decoding of the subsequent codewords. This allows an increment in the burst error correction capability of the whole block. There are some major weaknesses of this prior art. First, hardware ECC decoders are very sophisticated circuits, so dual decoders at the destination incurs extra complexity in hardware and development, especially for high data rate applications. Thus, the requirement of using two different decoders to decode an interleaved codeword is not desirable. A very important fact is that, in many systems, the encoding method, or equivalently, the signal format transmitted through the channel or the data format stored in the media, is already fixed because of the necessity of supporting existing legacy systems or open standards. Most of these systems use only one code and interleave. This prior art cannot be applied because it requires a change in the encoding scheme.
Therefore, there is a need in the technology to provide a more efficient method to encode and decode a data signal in a communication system that can be used with existing systems and standards.
The present invention provides a solution to this and other problems, and offers other advantages over the prior art.

Enhanced interleave type error correction method and apparatus


A TV stand is provided for supporting various sized TV sets at the optimal angle for viewing while lying in a bed, for supporting the TV at the optimal the height, for concealing the wiring of the set, and for minimizing the floor space occupied by the stand.

In this day of the "boob tube", everyone wants to watch TV everywhere; in the kitchen, in automobiles, in bars, and, most definitely, in bed. In most instances, bed time TV watchers place the TV on a nearby dresser, a table, or some other flat surfaced piece of furniture, resulting in less than optimal viewing angle and distance from the viewer. In the event the TV set is not remote controlled, the viewer must get out of the bed to change the channel, the volume, or otherwise adjust the set. Where the set is a console or is placed on a conventional TV stand the viewing angle is less than comfortable and a substantial amount of floor space is required. The present invention overcomes these and other problems and inconveniences associated with viewing a TV from a bed by positioning the TV at the optimal angle and the optimal distance from the viewer, with little obstruction of floor space.


A head bandanna is provided for protecting and covering the head area, which is used in sporting, recreational and work activities and includes a head covering made of fabric having a front and a rear portion, wherein the front portion has a front curved edge substantially in the shape of a semicircle. There is also a curved headband made of absorbent material and having the shape of a longitudinal strip and being integrally connected to the front curved edge of the front portion of the head covering at a 90.degree. angle facing downwardly relative to the headband. Velcro closure tabs are connected to opposite ends of the headband for fitting the head bandanna on the wearer's head in a conforming and secure fit.

Headwear or head coverings for work, sporting activities, or casual dress have taken many forms in relation to style, appearance, shapes, functionality, and types of materials used. Such headwear or head coverings have been in the forms of kerchiefs, bandannas, scarves, turbans, visor caps, beanies, helmets, and the like. Generally, these types of headwear or head coverings are used to protect the wearer's head from the sun, dirt/grime, and debris; and also, at certain times, they serve as sweatbands during vigorous athletic or work activities, absorbing the wearer's perspiration from the head and brow areas. There remains a need for a head covering that securely fits and conforms to the head and brow area and has an integral and curved headband for absorbing perspiration or grime from the brow area while also being effective in protecting the wearer's head and hair from the elements of sun, heat, cold, dirt, and the like.

Head bandanna having a headband with closure tabs


An information processing method and apparatus of this invention are a method and apparatus for multiplexing data indicating information other than video information on a video signal and transmitting the multiplexed data. Modulated data is formed by inputting the data and modulating the input data. The video signal and the modulated data are input, and the modulated data is multiplexed on the input video signal. When the multiplexed data is output, the modulation mode or the multiplexing interval of the modulated data is controlled in correspondence with the type of input data, thus realizing a function of multiplexing data on a video signal and transmitting the multiplexed data in correspondence with the data type with a simple, small-scale circuit arrangement.

1. Field of the Invention
The present invention relates to an information transmission method and apparatus for multiplexing data indicating information other than video information on a video signal, and transmitting the multiplexed data.
2. Related Background Art
A conventional system, which transmits a signal obtained by multiplexing data such as character data on a video signal, and receives and demultiplexes such signal into the video signal and data like in teletext broadcasting, is known.
However, the conventional system multiplexes modulated data on a specific interval (a portion of the vertical blanking interval) of a video signal, and the receiving side demodulates the specific interval alone to obtain data. More specifically, the modulation speed, the interval to be multiplexed, and the like of data are predetermined, and cannot be changed depending on the data volume, quality of line, and the like.
The arrangement of a video input apparatus shown in FIG. 1 will be described below as an example of a conventional information transmission system. A single-focus camera unit 100 serving as a video input unit is connected to an image processing unit 200 serving as a video processing unit. The image processing unit 200 is connected to a host unit 400 via a bus interface 208. The host unit 400 controls the image processing unit 200 and the single-focus camera unit 100 via the bus interface 208.
The arrangement of the single-focus camera unit 100 will be explained below. A system control unit 106 comprises a one-chip microcomputer having functions of a CPU, ROM, RAM, control port, communication port, and the like. The system control unit 106 controls the individual devices in the single-focus camera unit to make two-way communications with the image processing unit 200, and interprets commands as control data from the host unit 400 to execute operations requested by the host unit 400.
A lens unit 101 comprises a phototaking lens, focusing lens, and a focusing ring for manually moving the focusing lens. An iris unit 102 adjusts the amount of incident light that passes through the lens unit 101, and comprises an iris and an iris ring for manually moving the iris. An image sensing element 103 such as a CCD photoelectrically converts an image obtained via the lens unit 101 and the iris unit 102 into an electrical signal. An image sensing element driving circuit 105 such as a TG controls accumulation, reading, and resetting of the image sensing element 103 in correspondence with the number of pixels of the element 103. When the driving circuit 105 is controlled by the system control unit 106 via a control signal 110, the shutter speed can be changed. A synchronization signal generation circuit 108 such as an SSG generates video synchronization signals 112 such as a horizontal synchronization signal (HD), vertical synchronization signal (VD), video clocks, and the like on the basis of the clocks generated by the image sensing element driving circuit (TG) 105. An S/Hxc2x7AGC circuit 104 performs sampling and holding to reduce noise in charges accumulated in the image sensing element 103, and adjusts the gain of a video signal 114. The S/Hxc2x7AGC circuit 104 outputs the video signal 114. When the S/Hxc2x7AGC circuit 104 is controlled by the system control unit 106 via a control signal 111, it adjusts the gain of the video signal 114. A data multiplexing and demultiplexing unit 115 multiplexes the video signal 114 and control data from the system control unit 106, and transmits multiplexed data to the image processing unit 200. Also, the data multiplexing and demultiplexing unit 115 demultiplexes data from the image processing unit 200 and supplies the demultiplexed data to the system control unit 106. A data line and data control line 113 are used for two-way data communications between the single-focus camera unit 100 and the image processing unit 200, and are connected between the serial communication port of the system control unit 106, and the data multiplexing and demultiplexing unit 115. A connector 107 can be detached from the cable 109.
The video processing unit 200 will be described below. A system control unit 250 comprises a one-chip microcomputer having functions of a CPU, ROM, RAM, control port, communication port, and the like. The system control unit 250 performs control of the individual devices in the image processing unit 200, auto white balance control, communications with the single-focus camera unit 100, and communications with the host unit 400 via the bus interface 208. Also, the system control unit 250 interprets commands as control data from the host unit 400 and executes operations requested by the host unit 400.
A data multiplexing and demultiplexing unit 231 demultiplexes a video/data multiplexed signal 232 which multiplexes a video signal and data signal into a video signal 217 and a control data signal 222. Also, the data multiplexing and demultiplexing unit 231 multiplexes data from the system control unit 250 into a signal within the vertical synchronization interval, and transmits the signal to the single-focus camera unit 100.
An A/D conversion circuit 201 converts the video signal 217 transmitted from the single-focus camera unit 100 via the cable 109 into a digital signal 218. A signal processing circuit 202 performs processing for converting the converted digital video signal 218 into a standardized digital video signal 219. The signal processing circuit 202 generates an interrupt signal for informing the system control unit 250 of white balance data for white balance control. Upon recognizing the interrupt, the system control unit 250 reads out such information (white balance data, and the like) via a serial data line 223, and writes them in its RAM area.
An encoder circuit 204 converts the standardized digital video signal 219 into a multiplexed composite signal 221, and outputs the composite signal to a video output connector 210. An image memory 206 stores digital video signals 216 and 213 from the signal processing circuit 202 and an SRC (scan rate converter circuit) 207. A memory controller circuit 205 controls reads/writes in/from the image memory 206. The SRC 207 converts and absorbs the difference between the aspect ratios of the digital video signal 213 of the image processing unit 200 and a digital video signal 214 of the host unit 400. A switch circuit 203 selects an output signal 225 to the encoder 204 from a digital video signal 219 of the signal processing circuit 202 and the digital video signal 216 of the image memory 206, and is controlled by the system control unit 250 via a control line 224. The bus interface 208 is connected to the bus of a computer as the host unit 400. The bus interface 208 performs data communications of the digital video signal 214 and control data 226 between the host unit 400 and the image processing unit 200, and allows the host unit 400 to control the memory controller 205 and the SRC 207.
Video synchronization signals 215 of the image processing unit 200 correspond to the video synchronization signals 112 of the single-focus camera unit 100, and provide video synchronization signals to the signal processing circuit 202, the memory controller 205, and the encoder 204.
A serial data line and serial data control unit 222 are used for performing two-way data communications between the single-focus camera unit 100 and the image processing unit 200, and are connected to the serial data port of the system control unit 250.
A parallel data line and control unit 226 are used for performing two-way data communications between the host unit 400 and the image processing unit 200, and are connected to the control port of the system control unit 250.
FIG. 2 shows the transmission sequence of data 10 during the vertical blanking interval between the single-focus camera unit 100 and the image processing unit 200. A vertical synchronization interval Vhd t consists of a vertical blanking interval Vb and an effective video interval Va. Each data 10 is multiplexed on a video signal during the vertical blanking interval Vb.
When data communications are to be made between the single-focus camera unit 100 and the image processing unit 200, the length of data that can be transmitted within one vertical blanking interval Vb is limited.
In the case of FIG. 1, when the image processing unit 200 transmits control data such as command data and ACK data to the single-focus camera unit 100 within one vertical synchronization interval Vt, a maximum of 19 bytes=16 bytes (command data)+3 bytes (ACK data) must normally be transmitted. In this case, since this number of bytes is smaller than 32 bytes as the maximum number of bytes that can be transmitted within a single vertical blanking period Vb, all the data can be transmitted.
However, in the case of a zoom head which requires a large information volume to be transmitted, when vertical synchronization data generated for each synchronization interval is to be transmitted together with control data such as command data and ACK data, a maximum of 45 bytes=16 bytes (command data)+3 bytes (ACK data)+26 bytes (vertical synchronization data) must be transmitted. This number of bytes exceeds 32 bytes as the maximum number of bytes that can be transmitted within a single vertical blanking period Vb.
In this manner, when auto-focusing or automatic exposure is performed in a zoom camera unit, since the image processing unit 200 transmits data required for such control to the zoom head for each vertical blanking interval Vb, the volume of data to be transmitted increases. In the apparatus in which the density of the volume of information to be transmitted is high, data transmission cannot be completed within a single vertical blanking interval Vb.
It is an object of the present invention to provide an information transmission method and apparatus, which can solve the above-mentioned problems.
It is another object of the present invention to provide an information transmission apparatus which can realize a function of multiplexing data on a video signal in accordance with the data format used and transmitting multiplexed data, with an inexpensive, simple, and small-scale circuit arrangement.
In order to achieve the above objects, according to one embodiment of the present invention, an information transmission apparatus for multiplexing data indicating information other than video information on a video signal and transmitting the multiplexed data, comprises modulation means for forming modulated data by inputting the data and modulating the input data, and outputting the formed modulated data, multiplexing means for inputting the video signal and the modulated data output from the modulation means, multiplexing the modulated data on the input video data, and outputting the multiplexed data, and control means for controlling a modulation mode in the modulation means or a multiplexing interval of the modulated data in the multiplexing means in accordance with a type of data input to the modulation means.
It is still another object of the present invention to provide an information transmission apparatus which can efficiently transmit data together with a video signal.
In order to achieve the above object, according to one embodiment of the present invention, an information transmission apparatus for multiplexing data indicating information other than video information on a video signal and transmitting the multiplexed data, comprises transmission means for multiplexing and transmitting control data in a vertical blanking interval of the video signal in an identifiable state, and control means for controlling the transmission means to preferentially multiplex and transmit the control data when the transmission means has data to be multiplexed and transmitted in the vertical blanking interval in addition to the control data, and to multiplex and transmit the data, which cannot be multiplexed in the vertical blanking interval, during an interval other than the vertical blanking interval.
It is still another object of the present invention to provide an information transmission method which can efficiently transmit data together with a video signal.
In order to achieve the above object, according to one embodiment of the present invention, an information transmission method for multiplexing data indicating information other than video information on a video signal and transmitting the multiplexed data, comprises the transmission step of multiplexing and transmitting control data in a vertical blanking interval of the video signal in an identifiable state, and the control step of controlling a transmission operation in the transmission step to preferentially multiplex and transmit the control data when there is in the transmission step data to be multiplexed and transmitted in the vertical blanking interval in addition to the control data, and to multiplex and transmit the data, which cannot be multiplexed in the vertical blanking interval, during an interval other than the vertical blanking interval.

Information transmission method and apparatus


An electronic device may include a shaft insertable into a target area, and an electronic component configured to generate a signal. The electronic component may be on or within the shaft. The electronic device may also include at least one antenna on or within the shaft. The electronic device may also include a receiver operatively coupled to the antenna. The receiver may monitor an electrical characteristic of the antenna to identify an effect of an electromagnetic field on the electrical characteristic of the antenna. The electronic device may also include a processor communicatively coupled to the receiver. At least one of the receiver and the processor may predict an effect of the electromagnetic field on the signal generated by the electronic component, based at least in part on the effect of the electromagnetic field on the electrical characteristic of the antenna.

An electronic device may send, receive, and/or store an electrical signal when in use. During use, the electronic device may be exposed to an external electromagnetic field. The external electromagnetic field may be produced by another electronic device being used simultaneously in the same vicinity as the electronic device. The electromagnetic field may couple to the electronic device, causing an electromagnetic disturbance in the signal. The electromagnetic disturbance may degrade the quality of the signal, rending the signal inaccurate or even unusable. Shielding may be added to the electronic device in an attempt to block the electromagnetic field, thereby reducing the probability of the electromagnetic disturbance occurring, and/or reducing the severity of the effect the electromagnetic disturbance may have on characteristics of the signal.
In a medical environment, multiple electronic medical devices may be used simultaneously in the same vicinity. One of the electronic devices may remain outside of the subject's body. Another of the electronic devices may be used to access internal areas of the subject's body having large openings, passages, and cavities. Adding shielding to the electronic device that remains outside of the subject's body, and/or the electronic device used to access large openings, passages, and cavities, may be useful for protecting those electronic devices from external electromagnetic fields.
However, for an electronic device used to image internal areas of a subject's body having small openings, passages, and cavities, adding shielding may not be a viable option because the increase in size associated with adding shielding may make the electronic device too large to fit in the small openings, passages, and cavities of the subject's body. In one such electronic device, an image signal may be sent, received, and/or stored by the electronic device when it is used. If the electronic device is exposed to an external electromagnetic field, causing an electromagnetic disturbance in the image signal, one or more characteristics of the image signal may be affected. For example, one or more characteristics of the image signal may be degraded. The degradation may result in the image signal producing a single defective pixel, multiple defective pixels, or no image at all, on a display. Reducing such degradation may improve the performance of the electronic device.

This patent is subject to a terminal disclaimer.

Electronic devices and methods for addressing external electromagnetic fields


A tool mounting arrangement for a track press includes a bracket assembly for lateral and vertical adjustment of the tool mounting to compensate for variations in the spacing of the track components due to different amounts of wear. The bracket assembly includes a tool mounting plate which is connected to a reaction bar by an adjustment plate and a pair of brackets. A pair of threaded shafts penetrate the brackets and bear against the adjustment plate for moving the tool mounting plate vertically. A threaded rod is connected to the reaction bar and an adjustment wheel on the rod is in engagement with the adjustment plate for moving the tool mounting plate laterally. A pair of spring loaded apparatus maintain a preselected downwardly directed force on the bracket assembly.

Dis-assembling and re-assembling the components of endless track chains are often difficult, time consuming, and noisy tasks. The machines used for these tasks are generally quite large and utilize large diameter, high pressure fluid rams to press the track chain apart, or together for re-assembly.
During a dis-assembly procedure, the bushings of the track chain normally rest in a formed fixture, which positions the track chain for proper alignment with the press tools. As the dis-assembly operation progresses, each successive track chain joint is positioned in the fixture at substantially the same location, and the press tools move in to contact the pins and bushings of the joint. However, the bushings of the track chain often experience different amounts and rates of wear. When this occurs, the press tools do not align properly with the track joints, which can cause damage to the tools and the track components. Prior art press machines have attempted to solve this problem by using difficult means of adjustment, such as bolted in shim packs. These are time-consuming and cumbersome to use, and require storage of the various sizes of shims.
The present invention is directed to overcoming one or more of the problems as set forth above.

Tool mounting arrangement for a track press


An apparatus and method of operating a probe-based instrument in a torsional mode. The method includes providing a probe having a cantilever defining a longitudinal axis and supporting a tip. In operation, the method torsionally oscillates the probe generally about the longitudinal axis at a resonance. In addition, the method changes a separation distance between the tip and a surface of a sample so the tip interacts with the surface during data acquisition. By detecting a change in the torsional oscillation of the cantilever in response to the interaction between the tip and the surface, forces, including shear forces and shear force gradients, between the tip and the surface can be measured to determine sub-nanometer features.

1. Field of the Invention
The present invention is directed to probe-based instruments, and more particularly, a scanning probe microscope that is operable in a torsional mode by driving the probe into torsional resonance about its longitudinal axis.
2. Description of Related Art
Several probe-based instruments monitor the interaction between a cantilever-based probe and a sample to obtain information concerning one or more characteristics of the sample. Scanning probe microscopes (SPMs), such as the atomic force microscope (AFM), are devices which typically use a sharp tip and low forces to characterize the surface of a sample down to atomic dimensions. More particularly, SPMs typically characterize the surfaces of such small-scale sample features by monitoring the interaction between the sample and the tip of the associated probe assembly. By providing relative scanning movement between the tip and the sample, surface characteristic data and other sample-dependent data can be acquired over a particular region of the sample, and a corresponding map of the sample can be generated. Note that "SPM" and the acronyms for the specific types of SPMs, may be used herein to refer to either the microscope apparatus, or the associated technique, e.g., "scanning probe microscopy."
The atomic force microscope is a very popular type of SPM. The probe of the typical AFM includes a very small cantilever which is fixed to a support at its base and has a sharp probe tip attached to the opposite, free end. The probe tip is brought very near to or into direct or intermittent contact with a surface of the sample to be examined, and the deflection of the cantilever in response to the probe tip's interaction with the sample is measured with an extremely sensitive deflection detector, often an optical lever system such as described in Hansma et al. U.S. Pat. No. RE 34,489, or some other deflection detector such as an arrangement of strain gauges, capacitance sensors, etc.
Preferably, the probe is scanned over a surface using a high-resolution three axis scanner acting on the sample support and/or the probe. The instrument is thus capable of creating relative motion between the probe and the sample while measuring the topography or some other property of the sample as described, for example, in Hansma et al. U.S. Pat. No. RE 34,489; Elings et al. U.S. Pat. No. 5,226,801; and Elings et al. U.S. Pat. No. 5,412,980.
AFMs may be designed to operate in a variety of modes, including contact mode and oscillating flexural mode. In contact mode operation, the microscope typically scans the tip across the surface of the sample while keeping the force of the tip on the surface of the sample generally constant by maintaining constant deflection of the cantilever. This effect is accomplished by moving either the sample or the probe assembly vertically to the surface of the sample in response to sensed deflection of the cantilever as the probe is scanned horizontally across the surface. In this way, the data associated with this vertical motion can be stored and then used to construct an image of the sample surface corresponding to the sample characteristic being measured, e.g., surface topography. Alternatively, some AFMs can at least selectively operate in an oscillation "flexural mode" of operation in which the cantilever oscillates generally about a fixed end. One popular flexure mode of operation is the so-called TappingMode™ AFM operation (TappingMode™ is a trademark of the present assignee). In a TappingMode™ AFM, the tip is oscillated flexurally at or near a resonant frequency of the cantilever of the probe. When the tip is in intermittent or proximate contact with surfaces the oscillation amplitude will be determined by tip/surface interactions. The amplitude or phase of this oscillation is kept constant during scanning using feedback signals, which are generated in response to tip-sample interaction. As in contact mode, these feedback signals are then collected, stored, and used as data to characterize the sample.
Independent of their mode of operation, AFMs can obtain resolution down to the atomic level on a wide variety of insulating or conductive surfaces in air, liquid or vacuum by using piezoelectric scanners, optical lever deflection detectors, and very small cantilevers typically fabricated using photolithographic techniques. Because of their resolution and versatility, AFMs are important measurement devices in many diverse fields ranging from semiconductor manufacturing to biological research.
One limiting characteristic of AFMs and other probe-based instruments lies in the above-described modes of operation. In an AFM, the cantilever is typically oscillated using a piezoelectric drive, often known simply as a piezo drive, to provide, for example, a flexural oscillation mode. Referring to FIG. 1, a probe assembly 20 includes a probe 21 having a cantilever 22 and a tip 28. The cantilever 22 extends outwardly from a base 24 of assembly 20. The cantilever 22 may be attached to the base 24 or formed integrally with it. Base 24 is typically coupled to a piezoelectric drive 26 (e.g., a piezo stack). Tip 28 is provided on the opposed, free end of cantilever 22. Piezoelectric drive 26 can be selectively excited by a signal generator 30 to move cantilever 22 up and down relative to a sample 32. When the instrument is configured for flexural oscillation mode operation, the drive voltage is applied to piezoelectric drive 26 to flexurally oscillate the cantilever 22 about a lateral axis of the probe 20 at a frequency that is dependent upon the frequency of the drive voltage.
More particularly, in flexural oscillation mode, cantilever 22 is driven to resonate at its flexural resonance frequency or a harmonic thereof about a lateral axis A–A′ at the base 24 of cantilever 22. Characteristics of cantilever flexural oscillation, and changes thereof, are detected by quadrature photodetector 34, typically with its vertical components, as shown by the arrow "V" in FIG. 1. The deflection angle is sensed by photodetector 34 and output as a voltage signal. Notably, the amplitude of the flexural oscillation ranges between a few nm to 100 nm peak-to-peak depending on the cantilever length.
In operation, as tip 28 approaches a surface of sample 32, the flexural oscillation (tapping) amplitude starts to decrease due to contact between tip 28 and sample 32. Notably, the flexural vibration amplitude decreases to zero when tip 28 is pushed against sample 32 with constant contact pressure. Variation of amplitude between zero (generally continuous contact) and free oscillation is typically used in a feedback configuration to control tip/surface distance. Alternatively, the phase of the flexural oscillation may be used to control this distance. Information relating to the surface such as topology, hardness, and/or electromagnetic properties is then determined by analyzing the signals that are used to control this tip/surface spacing.
Overall, flexural oscillation mode AFMs are used to characterize surface topology and surface energy dissipation by monitoring the amplitude and/or phase of the oscillating cantilever. This mode is often preferred to contact mode imaging because it produces less damage to the tip and sample during operation. However, operating the AFM based on flexural oscillation of the cantilever is constrained in the following aspects.
Initially, flexural mode operation only detects surface characteristics that impart a force in one direction, namely, the vertical or "Z" direction. As a result, flexural mode AFMs do not detect shear force interaction, and thus also cannot provide shear force or force gradient information. This information is critical to making measurements of surface friction, for example, when attempting to identify surface compositional differences. When the topography of the materials is generally undifferentiated, minimal information is provided by flexural mode operation, and thus this friction information becomes particularly valuable, and sometimes necessary. Applications include identifying different components in polymer blends, composites and other mixtures, identifying organic and other contaminants on sample surfaces, delineating coverage by deposited coatings and other surface layers, etc.
Moreover, without shear force or shear force gradient measurement capabilities, flexural mode operation often results in loss of other information relating to the sample. For example, when a flexural oscillation mode AFM is used to image the magnetic domain of a sample, only a force gradient in the direction perpendicular to the sample surface can be sensed. Domains parallel to the surface can only be seen at the domain boundaries where the transitional region has a vertical force gradient. This limitation also holds true for electric force imaging.
Other drawbacks associated with flexural resonance imaging are slow kinetics and small amplitude errors that can drastically limit scanning and data acquisition speed and compromise image integrity. This effect is illustrated in the response curve 40 of FIG. 2. In this case, AO is the free air amplitude of oscillation (in RMS voltage), and AS is the set-point amplitude. When tip/sample separation is reduced, and the tip and sample interact, there is a corresponding change in the signal produced by the deflection detection system. The amplitude of flexural oscillation of the lever decreases due to it being constrained by the sample surface as the tip approaches the surface and taps the sample in each stroke of the oscillation. This is shown in region "O" in which tip-surface distance (x-axis) is smaller than half of the peak-to-peak oscillation of the cantilever. Notably, a feedback loop operates to move the cantilever up and down to keep generally the same oscillation amplitude AS. This movement reflects height changes in the sample, i.e., surface topography.
The response of the cantilever in this flexural mode is illustrated by the slope of the curve at region "O." In other words, for a particular change in tip/sample separation, the corresponding measured change in voltage is relatively small. It is this measured change that determines the error that is processed by the feedback loop to return operation to the set-point oscillation. Because the slope of the cantilever response in flexural mode is relatively shallow, scan speed must be kept small as relatively large changes in tip-sample separation produce a relatively small change in measured output, or error. Therefore, to facilitate adequate data collection and integration of error signals, the scan time at each location (or image pixel) must be long enough for the system to respond with accuracy and resolution. The speed of data acquisition must be correspondingly limited as well. An improvement in data acquisition speed was desired.
Moreover, the shallow slope of the amplitude/distance curve in FIG. 2 makes the control signal (voltage in the vertical axis) correspond to a large height or distance compared to an amplitude/distance curve with a steeper slope. As a result, the control error will correspond to a greater quantity of height measurement error. The situation is particularly problematic when the probe is scanning across an abrupt step where slower response due to error integration will result in even greater inaccuracy for a given scan speed. Notably, such inaccuracy may be detrimental to obtaining useful data in semiconductor metrology.
Yet another limitation with flexural mode operation is that the flexural resonance is very sensitive to the imaging environment (e.g., when the sample is immersed in water), and thus oscillation properties often change drastically, and in unpredictable ways, upon change in imaging environment. Currently, the sensitivity of flexural mode operation to imaging environment is one of the most significant design considerations when configuring an AFM for operation in fluid.
Other modes of AFM operation are similarly limited. For example, shear force interaction between the probe in contact mode and the corresponding sample surface has been studied with AFM for a number of years. In an AFM technique known as lateral force microscopy (LFM), the cantilever tip is dragged across the sample surface, as in contact mode, to measure friction forces, as described in U.S. Pat. No. 5,553,487 to the present assignee. More particularly, using LFM, the tip is introduced to the sample surface under a constant deflection and then scanned along the surface either in the direction of the cantilever length, or perpendicular to the cantilever length. Using a laser-based deflection detection system, the lateral cells of the corresponding photodetector sense rotation of the cantilever as the tip of the probe interacts with the sample through friction force. In the case where tip scanning direction is perpendicular to the cantilever, the difference of the lateral deflection during forward and reverse scanning of the same portion of the sample is used as a relative measure of the shear force, or surface friction. In addition to the drawbacks associated with using contact mode to detect topology characteristics, including tip/sample damage, etc., LFM suffers the disadvantage of poor lateral resolution and poor repeatability.
In other techniques, the tip placed in contact with the sample surface is modulated by moving the sample surface laterally relative to the probe. In this case, the lateral rocking of the cantilever as a result of the contact friction is used to indicate a quantity of surface friction. However, the lateral deflection signals are small, and thus often unusable, and resolution is insufficient for some of the applications contemplated by the present invention.
In addition, although lateral deflection signals induced by motion of the sample at acoustic frequencies can be enhanced, the main control loop that defines tip/surface relative position still employs vertical deflection (contact mode) feedback and, therefore, suffers the drawbacks associated with that technique, including slow kinetics, and inability to image a shear force gradient.
As a result, the metrology and other research fields were in need of a probe-based instrument capable of detecting multi-directional forces with improved imaging speed. More particularly, an AFM capable of imaging shear forces and shear force gradients with components exhibiting fast response dynamics was desired.

Torsional resonance mode probe-based instrument and method


An image collation device such as a fingerprint collation device for specifying a plurality of frames for an inspection object, cutting a plurality of linear images from each frame, determining whether images coincide with each other in each frame with reference to a plurality of cut linear images, determining the determination results on a overall basis, and finally determining the coincidence, enabling consistent collation results with a simple structure.

1. Field of the Invention
This invention relates to an image collation device, which is applied, for example, as a fingerprint collation device. The device of the present invention involves the operation that a plurality of frames are specified for an inspection object, a plurality of linear images are cut from each frame, the coincidence between images in each frame is determined with reference to a plurality of cut linear images, this determination results are determined on an overall basis to finally determine the coincidence between the images, and thereby the image collation device can obtain the result of collation between images such as fingerprint image consistently.
2. Description of the Related Art
Heretofore, in the conventional fingerprint collation device using an image collation device of this sort, featured points such as a branch, point, and cut (referred to as featured point hereinafter) are extracted from a fingerprint image obtained by means of an image pick-up device, and fingerprint collation is performed with reference to these featured points.
In other words, in the conventional fingerprint collation device, a fingerprint to be collated is previously converted to database with reference to, for example, featured points and coordinate values. A fingerprint image to be subjected to fingerprint collation is subjected to image processing in order to extract featured points. Then, a database has an access to the extracted featured points and the fingerprint is collated based on the existence of corresponding featured points.
The conventional fingerprint collation is disadvantageous in that fingerprint collation takes a long time. If fingerprint collation is carried out consistently within a short time, the fingerprint collation device provides improved convenience for use, and such improvement is desirable.
To solve this problem, there may be one method that linear images are cut from a fingerprint image to be inspected, and the cut linear images are moved successively on a image to be determined, thereby comparison results are obtained. In this method, the degree of similarity can easily be detected, but there is a problem that no consistent collation result can easily be obtained.


A semiconductor device comprises: a semiconductor layer of a first conductivity type; a pair of base regions of a second conductivity type selectively provided on a surface of the semiconductor layer; and source regions of a first conductivity type, each of the source regions being selectively provided on a surface of each of the base regions. The semiconductor device further comprises an electrical field reducing region of a second conductivity type selectively provided on the surface of the semiconductor layer between the pair of the base regions; a gate insulating film provided on the surface of the base regions; a pair of gate electrodes provided on the gate insulating film, each of the gate electrodes being provided on the surface of the base regions between the source region and the electrical field reducing region; and a source electrode connected to the source regions. The electrical field reducing region is isolated from both of the gate electrode and the source electrode.

The present invention relates to a semiconductor device, and more particularly, it relates to a semiconductor device which has a lateral type or vertical type field effect transistor structure, and is suitably applied as a device for high-speed switching or a device for power control.
As the supply voltage for CPUs decreased, the power supply with the synchronous rectification system using a field effect transistor is being greater used.
FIG. 19 is a schematic diagram showing the cross-sectional structure of MOSFET (Metal-oxide-Semiconductor Field Effect Transistor) used for such a power supply. Hereafter, a n channel type will be explained. It is also possible to acquire the similar structure about p channel type by reversing p type and n type for each semiconductor part.
This MOSFET has the so-called "vertical type" structure, where n type semiconductor region 104 is provided on n+ type substrate 102, and p type base regions 106 are selectively formed on the surface of the n type semiconductor region 104. Moreover, n+ type source region 108 is selectively formed on the surface of the p type base region 106, and a gate oxide film 110 and a gate electrode 112 are formed on the p type base region 106 and n− type semiconductor region 104 between the n+ type source region 108 and the neighboring n+ source region 108.
The source electrode 114 is connected to n+ type source region 108, and the drain electrode 116 is connected to the back side of n+ type substrate 102. By applying a bias voltage to the gate electrode 112, a channel can be formed on the surface of p+ type base region 106, and a current can be passed between the source and the drain.
However, in the semiconductor device illustrated in FIG. 19, since the facing area between the gate and the drain is large, and since the gate and the drain have countered through gate oxide 110, the feedback capacitance between the gate and the drain is large. This feedback capacitance is one of the parameters which impede high-speed operation of the semiconductor device and increase switching loss. Therefore, it is desirable to reduce the feedback capacitance between the gate and the drain.
On the other hand, narrowing the interval between p type base regions 106 and 106 may also be considered so that the facing area between a gate and a drain may be reduced. However, in this case, since the current path between drain and source is constricted, the JFET resistance Rj corresponding to resistance of this current path becomes high, and electrical connection loss increases.
As mentioned above, in the conventional MOSFET, there was a relation of a trade-off between ON resistance and the feedback capacitance, and there was a problem that there was a limit in reducing high-speed operation, electrical connection loss, and switching loss.


A child-resistant/senior friendly dispensing package comprising a dispensing member having a dispensing cavity and a product storage cavity, the dispensing member being mounted within a sleeve movable from a first stored position to a second position wherein the dispensing cavity is exterior of the housing to permit dispensing of the product, a device having first and second locks which must be operated either sequentially or simultaneously in order to move the dispensing cavity exteriorly of the housing. The device preferably permits the dispensing of only a single tablet or product.

The use of child-resistant packaging is well known in the art and is utilized for many different types of goods. Primarily, this type of packaging is used for those products which represent a potential hazard in the hands of children—i.e. medicants and the like. The approach adopted for the child resistant packaging usually depends upon the product per se—i.e. its size, format, etc. Thus, for example, in the field of medicines many different types of pill containers have locking tops. These locking tops can only be released by performing a manocuver while turning the top. Generally, one may be required to either depress or lift the top while turning in order to disengage various locking mechanisms. Similarly, it is known in the art to package tablets in different types of blister packages which are designed to prevent easy access by children.
In designing child-resistant packages, it is also important that the package can be opened without undue difficulty by the average consumer for whom the product is intended. This is frequently a problem in that one of the primary groups of medicant users are the elderly, and packaging which relies on the user having a certain amount of strength to open the packages is often self-defeating in that the elderly find it difficult or impossible to open such packaging. This has led to the use of the term "senior friendly" packaging.


An apparatus and method for maximizing the radiation shielding for spent nuclear fuel during cask transfer procedures. In one aspect, the method comprises submersing an apparatus having a jacket and a cavity for receiving spent nuclear fuel into a pool, wherein the jacket is empty and hermetically sealed; placing spent nuclear fuel into the cavity of the apparatus; lifting the apparatus from the pool; placing the apparatus in a staging area; filling the jacket with neutron absorbing liquid; draining the pool water from the cavity; and lifting the apparatus from the staging area. In another aspect, the invention is an apparatus comprising a cylindrical inner shell forming a cavity within which spent nuclear fuel can be placed; a cylindrical outer shell concentric with and surrounding the inner shell to form an annulus with the inner shell, the annulus adapted for receiving gamma absorbing material; a jacket shell concentric with and surrounding the second shell to form a jacket for holding a neutron absorbing liquid; and the jacket shell having a filling means and a drainage means.

This invention relates to the field of transporting spent nuclear fuel and specifically to maximizing radiation shielding during spent nuclear fuel transfer procedures.
In the operation of nuclear reactors, it is customary to remove fuel assemblies after their energy has been depleted down to a predetermined level. In the commercial nuclear industry, fuel assemblies are typically an assemblage of long, hollow, zircaloy tubes filled with enriched uranium. Upon depletion and subsequent removal, spent nuclear fuel is still highly radioactive and produces considerable heat, requiring that great care be taken in its packaging, transporting, and storing. Specifically, spent nuclear fuel emits extremely dangerous neutrons and gamma photons. It is imperative that these neutrons and gamma photons be contained at all times.
Upon defueling a nuclear reactor, spent nuclear fuel is placed in a canister that is submerged in a storage pool. The storage pool facilitates cooling of the spent nuclear fuel and provides radiation shielding that helps contain the emitted neutrons and gamma photons. Generally, canisters are cylindrical steel containers with flat bottoms. A typical canister can hold approximately 24 PWR fuel assemblies or 60 BWR fuel assemblies. When fully loaded with spent nulclear fuel, a canister weighs approximately 45 tons. However, a canister alone does not provide adequate containment of the neutrons and gamma photons emitted by the spent nuclear fuel contained therein. As Such, a loaded canister cannot be further transported from the storage pool without some additional radiation shielding. Because it is preferable to store spent nuclear fuel in a xe2x80x9cdry state,xe2x80x9d the canister must eventually be removed from the storage pool. As such, apparatus that provide additional radiation shielding during transport and long-term dry storage of the spent nuclear fuel are necessary.
In state of the art facilities, additional radiation shielding is achieved by placing the loaded canisters in large cylindrical containers called casks. There are two types of casks used in the industry today, storage casks and transfer casks. A transfer cask is used to transport canisters of spent nuclear fuel from location to location while a storage cask is used to store spent nuclear fuel in the xe2x80x9cdry statexe2x80x9d for long periods of time. Both transfer casks and storage casks are designed to shield the environment from the neutron and gamma radiation emitted by the spent nuclear fuel through the use of two principles.
First, the gamma radiation emitted by spent nuclear fuel is blocked by placing mass in its way, the greater the density and thickness of the blocking mass, the more effective the attenuation of the gamma radiation. Examples of effective gamma absorbing materials are concrete, lead, and steel. Second, the neutrons emitted by spent nuclear fuel are blocked by placing a material containing hydrogen atoms in their path. As such, any material rich in hydrogen is an effective neutron shield. One example of an effective neutron absorbing material is water.
Guided by the above principles, storage casks are designed to be large, heavy structures made of steel, lead, concrete and an environmentally suitable hydrogenous material. However, because the focus in designing a storage cask is to provide adequate radiation shielding for the long-term storage of spent nuclear fuel, size and weight are often secondary considerations (if considered at all). As a result of maximizing the thickness of the gamma and neutron absorbing materials, the weight and size of storage casks often cause problems associated with lifting and handling. Typically, storage casks weigh approximately 150 tons and have a height greater than 15 ft. A common problem is that storage casks are often too heavy for the capacity of most nuclear power plant cranes and as such cannot be lifted. Another common problem is that storage casks are too large to be placed in storage pools. Thus, in order to store spent nuclear fuel in a storage cask, a loaded canister must be removed from the storage pool, prepared in a staging area, and transported to the storage cask. Additional radiation shielding is needed throughout all stages of this procedure.
Removal from the storage pool and transport of the loaded canister to the storage cask is facilitated by a transfer cask. In facilities utilizing transfer casks to transport loaded canisters, an empty canister is placed into an open transfer cask. The canister and transfer cask are then submerged in the storage pool. As each assembly of spent nuclear fuel is depleted, it is removed from the reactor and lowered into the storage pool and placed in the submerged canister (which is within the transfer cask). The loaded canister is then fitted with its lid, enclosing the spent nuclear fuel and water from the pool within. The enclosed water provides neutron radiation shielding for the spent nuclear fuel once the transfer cask is removed from the pool. The canister and transfer cask are then removed from the pool by a crane and set down in a staging area to prepare the spent nuclear fuel for storage in the xe2x80x9cdry state.xe2x80x9d Once in the staging area, the water contained in the canister is pumped out of the canister. This is called dewatering. Once dewatered, the spent nuclear fuel is allowed to dry. Once dry, the canister is back-filled with an inert gas such as helium. The canister is then sealed and the canister and the transfer cask are once again lifted by the plant""s crane and transported to the storage cask. The transfer cask is placed atop the storage cask and the canister is lowered through a bottom opening in the transfer cask into the storage cask.
Because a transfer cask must be lifted and handled by a plant""s crane (or other equipment), transfer casks are designed to be a smaller and lighter than storage casks. A transfer cask must be small enough to fit in a storage pool and light enough so that, when it is loaded with a canister of spent nuclear fuel, its weight does not exceed the crane""s rated weight limit. Additionally, a transfer cask must still perform the important function of providing adequate radiation shielding for both the neutron and gamma radiation emitted by the enclosed spent nuclear fuel. As such, transfer casks are made of a gamma absorbing material such as lead and contain a neutron absorbing material. While the pool water sealed in the canister does provide some neutron shielding, this water is eventually drained at the staging area. As such, many transfer casks have either a separate layer of neutron absorbing material or have an annulus filled with water that surrounds the cavity of the transfer cask in which the loaded canister is located.
As stated earlier, the greater the thickness and density of the neutron and gamma absorbing materials, the greater the radiation shielding provided thereby. However, increasing the density and/or thickness of the materials used to make the transfer cask also results in the weight of the cask being increased. Thus, the extent of radiation shielding provided by a transfer cask is directly related to the transfer cask""s weight. The greater the radiation shielding the greater the weight of the cask.
However, the allowable weight of a transfer cask is limited by the lifting capacity of the plant""s crane (or other lifting equipment). The load handled by the crane includes not only the weight of the transfer cask itself, but also the weight of the transfer cask""s payload (i.e., the canister and its contents). A transfer cask must be designed so that the total load handled by the crane during all handling evolutions does not exceed the crane""s rated weight limit, which is typically in the range of 100-125 tons. As such, the permissible weight of a transfer cask is equal to the rated capacity of the plant crane less the weight of its payload. Moreover, it is important to note that when the combined weight of a transfer cask and its payload is equal to the rated lifting capacity of the plant crane, the possible radiation shielding that can be provided by a transfer cask is at a maximum for that particular payload. This is because the thickness of the gamma and neutron absorbing materials are at a maximum for that crane and that payload.
Because the weight of the transfer cask""s payload varies during the different stages of the transport procedure, the permissible weight of the transfer cask is equal to the rated capacity of the plant crane less the weight of the transfer cask""s maximum payload at any lifting step. The weight of the transfer cask""s payload is at a maximum when the transfer cask and canister are lifted out of the storage pool, at which time the canister is full of spent nuclear fuel and water. Thus, according to prior art methods, it is at this stage that the permissible weight of a transfer cask is calculated. The transfer cask is then constructed using this permissible weight as a design limitation.
However, when the transfer cask is set down in the staging area, the pool water is removed from the canister. Upon completion of dewatering the canister, the weight of the transfer cask""s payload is reduced below the rated capacity of the crane, and remains so throughout the rest of the transport procedure. As such, the radiation shielding capacity provided by the transfer cask is sub-par throughout the rest of the procedure when compared to a heavier transfer cask, the weight of which would subsume the available crane capacity. However, a heavier transfer cask can not be used throughout the entire transport procedure because of the fact that the combined weight of the heavier transfer cask and its payload would exceed the rated lifting capacity of the crane during the step of initially lifting the transfer cask from the storage pool. Thus, the maximum amount of radiation shielding is not provided throughout every step of the transfer and dry storage procedure.
While it is possible to transfer the canister of spent nuclear fuel to a heavier transfer cask once the payload is lightened from dewatering, this would take added time, money, effort, space, and equipment. An additional transfer would also increase the amount of radiation exposure to personnel and the chances of a handling mishap. Thus a need exists for a transfer cask that can provide the maximum amount of radiation shielding during all stages of transferring spent nuclear fuel from a storage pool to a storage cask for long-term dry storage, even when the weight of the transfer cask""s payload is varied. A need also exists for a method of transferring a canister of spent nuclear fuel from a storage pool to a storage cask for long-term dry storage that provides the maximum amount of radiation shielding during all stages of the transfer procedure, even when the weight of the transfer cask""s payload is varied.
It is an object of the present invention to provide an apparatus that can provide the maximum amount of radiation shielding during all stages of a spent nuclear fuel transfer procedure, even when the weight of the apparatus""s payload is varied.
Another object of the present invention is to provide an apparatus for transferring spent nuclear fuel, the weight of which can be easily and quickly varied in order to maximize the amount of radiation shielding for a varied payload without substantially increasing the transfer procedure cycle time.
Yet another object of the present invention is to provide an apparatus for transferring spent nuclear fuel that can be lifted and transported by a low-capacity crane and still provide adequate radiation shielding during all stages of the transfer procedure.
Still another object of the present invention is provide a method of transferring a canister of spent nuclear fuel that provides the maximum amount of radiation shielding during all stages of the transfer procedure, even when the weight of the apparatus""s payload is varied.
Yet another object of the present invention is to provide a method of transferring a canister of spent nuclear fuel in nuclear power plants having a low capacity crane that provides adequate radiation shielding during all stages of the process.
These objects and others are met by the present invention which in one aspect is an apparatus for transferring spent, radioactive nuclear fuel comprising a cylindrical inner shell forming a cavity within which spent nuclear fuel can be placed; a cylindrical outer shell concentric with and surrounding the inner shell to form an annulus with the inner shell, the annulus adapted for receiving gamma absorbing material; a jacket shell concentric with and surrounding the second shell to form a jacket for holding a neutron absorbing liquid; and the jacket having a filling means and a drainage means.
It is preferable that the drainage means and filling means be adapted so that the jacket can be filled and drained with neutron absorbing liquid during a spent nuclear fuel transfer process. Preferably, the jacket shell of the apparatus has a top and a bottom, the filling means being located at or near the top of the jacket shell and the drainage means being located at or near the bottom of the jacket shell.
The filling means are preferably one or more holes capable of being hermetically sealed. Also preferably, the drainage means is one or more drain valves capable of being opened and hermetically sealed.
The gamma absorbing material is preferably lead and the neutron absorbing liquid is preferably water. The inner shell and outer shell are preferably constructed of carbon steel. It is also preferable that the apparatus further comprise a plurality of radial plates located within the jacket, wherein the radial plates connect the outer shell and the jacket shell. Preferably, the jacket shell is constructed of carbon steel. Also preferably, the annulus is filled with gamma absorbing material.
In another aspect, the invention is a method of transferring spent nuclear fuel from a pool comprising submersing an apparatus having a jacket, a cavity, and a canister within the cavity, for receiving spent nuclear fuel into a pool so that the canister fills with pool water, wherein the jacket is empty and hermetically sealed; placing spent nuclear fuel into the canister; lifting the transfer cask from the pool; placing the transfer cask in a staging area; filling the jacket with neutron absorbing liquid; draining the pool water from the canister, thereby reducing the weight of the transfer cask; and lifting the apparatus from the staging area.
Preferably, the method further comprises draining the neutron absorbing liquid from the jacket; hermetically sealing the jacket; and submersing the transfer cask in the pool for another load of spent nuclear fuel.
It is preferable that the jacket is drained by activating drainage means being located at or near the bottom of the jacket. Preferably, the drainage means is one or more drain valves which are hermetically sealed when the transfer cask is in the pool and after the jacket is filled.
Also preferably, the jacket is filled by introducing neutron absorbing liquid through the filling means being located near the top of the jacket. The filling means can be one or more holes which are hermetically sealed when the transfer cask is in the pool and after the jacket is filled.
The method preferably further comprises backfilling the canister with an inert gas once the pool water is drained. It is also preferable for the method to further comprise positioning the transfer cask above a storage cask; and transferring the canister from the transfer cask to the storage cask. Alternatively, the method can further comprise positioning the transfer cask above a transport cask; and transferring the canister from the transfer cask to the transport cask.

Method and apparatus for maximizing radiation shielding during cask transfer procedures


A multispectral imaging device comprises a first photoelectric conversion module and a second photoelectric conversion module. The first photoelectric conversion module further includes a first photoelectric conversion layer located between a first conducting layer and a second conducting layer. The first conducting layer, coupled to a first constant potential, is configured to allow visible light and infrared light to pass through. The first photoelectric conversion layer is configured to convert the visible light into a first electrical signal. The second photoelectric conversion module, formed on a silicon substrate, is configured to receive the infrared light coming from the first photoelectric conversion module. The second photoelectric conversion layer located between a third conducting layer and a fourth conducting layer, wherein the third conducting layer is configured to allow the infrared light passing through, the second photoelectric conversion layer is configured to convert the infrared light into a second electrical signal.

Infrared cameras are widely used in medical image diagnosis, biometrics, night vision, auto-driving, and machine vision. In many applications, live images of an object in both visible light and infrared light, are required and referred each other or aligned each other pixel to pixel to better understand the space structure and various characteristics of the object. For this purpose, multispectral imaging systems with dual-camera, capable of capturing visible light image and infrared light image separately have been developed. However, the dual-camera system has drawbacks such as bulky, high cost, and complexity in aligning two images acquired in separated optical axis.
It is therefore the primary object of this disclosure to realize a multispectral imaging device capable of capturing visible light (color or black-white) and infrared light in a compact format.


A sound effect-creating device for imparting a sound effect to a musical tone produced by performance delays a musical tone signal of an analog or digital type by a predetermined delay time to repeatedly generate the musical tone. The predetermined delay time is set based on a basic delay time determined from the period of a timing clock of a MIDI signal received from an external electronic musical instrument. Alternatively, the period of a timing clock of a MIDI signal is determined from a basic delay time set for determining the predetermined delay time.

1. Field of the Invention
This invention relates to a sound effect-creating device used in electronic musical instruments and the like, and more particularly to a sound effect-creating device which is adapted to determine a predetermined delay time based on a repetition period of a timing clock of a MIDI signal, or vice versa, in imparting a repeat effect to a musical tone.
2. Prior Art
It is a known excellent technique in playing musical instruments or singing in chorus, to delay musical tones produced by the instruments or voices of singers by the use of a delay device to impart a repeal effect thereto, and thereby make particular potions of the performance or the chorus emphatic or impressive. To make use of this technique, a sound effect-creating device comprising such a delay device is generally used today, i.e., at the age of rapid progress in the art related to electronic musical instruments, to impart a repeat effect to the performance.
In imparting a repeat effect to the performance and/or song (hereinafter simply referred to as "the performance") by the use of such a sound effect-creating device, it is a conventional method that an operator of the sound effect-creating device calculates a delay time based on the tempo of the performance, whenever it is required, or determines the delay time by the use of a converting table set therefor, and then the thus obtained delay time is set to the delay device of the sound effect-creating device.
However, this method has the following inconveniences: First, it is naturally required to make the tempo of performance of a musical instrument playing an accompaniment completely synchronous with the delay time for delaying the musical tone of the performance. Otherwise, the repeated tone or the delayed musical tone does not agree with the accompaniment, and impedes the performance to the contrary. According to the conventional method, the delay time of the sound effect-creating device for delaying the musical tone is set by the operator separately from the electronic musical instrument for the accompaniment, which prevents the tempo of the accompaniment of the electronic musical instrument from being completely synchronous with the delay time for delaying the musical tone. Furthermore, if the tempo of the performance or the accompaniment is changed during the performance, it is impossible to change setting of the delay time, since this will impede progress of the performance.
Secondly, such calculation or use of a converting table in determining a delay time is not preferred, since it is not only troublesome but also unbecoming to the performance of music which should be based on sensitivity by nature.


An improved electrolytic loudspeaker assembly (10) designed to reproduce a broad band of audio signals and that consists of a thin, non-magnetic capacitive transducer (12) and a transducer driver unit (60). The transducer (12) consists of a compound diaphragm (14) further consisting of a vibratory center section (16) having attached to each of its surfaces a respective front section (26) and back section (32). All three sections of the compound diaphragm are held captive by a frame assembly (40). The transducer (12) is driven and controlled by the transducer driver unit (60). The unit couples the audio signal to the transducer's front and back sections (26) (32) and supplies an unregulated, d-c bias voltage to the transducer's center section (16). The unit (60) maintains the proper ratio between the bias voltage and audio signal to achieve optimum performance.

Since the advent of "high fidelity" audio systems, engineers have strived to develop loudspeakers that were relatively free from distortion and with a frequency response that would allow concert hall music to be closely reproduced. Loudspeakers are broadly categorized as being either magnetic, moving coil speakers or non-magnetic, electrostatic speakers/transducers. The instant invention discloses an electrolytic speaker which is more closely related to the electrostatic types. Therefore, the reminder of the discussion pertains to only electrostatic speakers.
Most prior art electrostatic speakers generally consist of a center flexible membrane or diaphragm having on each side a fixed electrode in the form of a grid of wires. The wires are spaced apart so as to enable sound waves generated by the movement of the flexible membrane to be emitted. The wires are sheathed in a dielectric insulation material and the flexible membrane has a coating of a highly resistive material. The membrane is further suspended within an open latticed frame between the electrode wires so that when operated, relatively small segments of the diaphragm are enabled to vibrate under the influence of the electrostatic fields acting upon the diaphragm.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention however, the following U.S. patents were considered related:
______________________________________ U.S. Pat. No. INVENTOR ISSUED ______________________________________ 4,160,882 Driver 10 July 1979 3,942,029 Kawakami et al 2 March 1976 3,705,312 Sessler et al 5 December 1972 3,345,469 Rod 3 October 1967 ______________________________________
The Driver patent discloses an electrostatic transducer that has applicability as a loudspeaker. The transducer consists of two parallel diaphragms each consisting of two plastic sheets, having different charge carrying characteristics, that are sandwiched between an electrically conductive layer. The two diaphragms are separated by a centrally located perforated electrically conductive sheet and a dielectric material sandwiched between the conductive sheet and each diaphragm. The diaphragm's two electrically conductive layers are connected across the secondary winding of an audio transformer and the centered electrically conductive sheet is connected to the center tap of the transformer. Thus, when the transformer is applied an audio signal the two diaphragms are driven in a push-pull relation to reproduce the audio.
The inventor of the U.S. Pat. No. 4,160,882 is also the inventor of the instant application and pending application Ser. No. 07/949,801. The instant application differs from both the patent and the pending application in that the transducer driver unit has been redesigned and the improved electrolytic loadspeaker assembly no longer requires polarization or a bias regulator/dielectric drain circuit.
The Kawakami et al patent discloses an electrostatic transducer that can be utilized in either a speaker or microphone. The transducer consists of a vibrating plate or electret diaphragm having a monocharge of positive or negative potential on its surface. The electret diaphragm is made of a thin polymer film that is bonded to a support so that uniform tension exists. A pair of electrically conductive electrodes are brought in contact with opposite sides of the polymer films, and an electrostatic shield, such as a mesh, covers the surface of the two electrodes. A d-c voltage is time-applied across the electrodes to allow the electret to heat to its curie temperature of 120.degree. C. The electret is subsequently cooled to produce a quasi permanent state of electric polarization.
The Sessler patent discloses a method for preparing a thin-film electret. The method includes placing a thin polymer film between two electrodes together with a dielectric plate. A voltage of about 30 keV is then applied across the resulting sandwich of elements for about one minute at room temperature and at atmospheric pressure. The method produces charge-densities which are greater by a factor of three than those previously reported.
The Rod patent discloses a loudspeaker that operates on electrostatic principles. The speaker consists of a centrally located movable diaphragm which is coated on both sides with a thin, flexible electrically conductive layer. On each side of the diaphragm is located at least one hermetically sealed plastic dielectric sheet. When air or other gas is trapped between the sheets and the diaphragm, a buffer zone is created. To each outermost dielectric sheet is attached an electrode and to the centered conductive diaphragm is likewise attached an electrode. The two buffer electrodes are connected across the secondary winding of a step-up transformer and the diaphragm electrode is connected through a d-c voltage source to the centertap of the transformer. The transformer's primary winding is connected to the diaphragm driving signal that is derived from the signal input from a conventional low-impedance amplifier.
The above described electrostatic transducers, although being superior in many respects over the moving-coil type, have received poor industry/consumer acceptance. This poor acceptance is due in part to the undue mechanical complexity of some designs, low acoustic output, the requirement for a comparatively large radiating area and a dependence upon the application of a relatively high d-c polarizing bias voltage between the flexible diaphragm and the wire grid electrodes. For example, a typical full range push-pull electrostatic speaker requires a bias voltage of 3500 volts d-c and a driving amplifier with a power capacity of from 60 to 100 watts. Additionally, the prior art electrostatic speakers are only able to reproduce adequately from the mid-range and higher audible frequencies. Therefore, a bass speaker is commonly connected to reproduce the bass frequencies.
To overcome some of the above defects, transducers utilizing electrets as the diaphragm have been employed. The electret diaphragm was thought to be permanently polarized or charged and therefore not requiring a separate polarizing d-c voltage. However, these electrets have been found to be unsatisfactory for application as loudspeakers because they decay, at least to a first approximation, according to an equation of the form dp/dt=oc P because the misalignment of the partially oriented dipoles is a random process.
For background purposes and as indicative of the art to which the invention relates, reference may be made to the following remaining patents found in the
______________________________________ PATENT NO. INVENTOR ISSUED ______________________________________ 4,726,443 Ugaji, et al 23 February 1988 3,941,946 Kawakami et al 2 March 1976 2,037,537 (GB) Kawasaki 9 July 1980 ______________________________________


Electrical connection is established between the lead electrodes and the pacemaker terminals whereby a straight length of coil spring is placed within a hole transverse to the lead hole. A portion of the transverse hole intersects the lead hole so that a portion of coil spring extends transversely into the lead hole. The ends of the coil spring section are welded on opposite sides of the terminal. Electrical connection is made as the spring contacts the ring electrode on the lead.

The present invention relates to an electrical connector for a cardiac pacemaker for connecting an electrode lead to a terminal on the pacemaker.
Implantable pacemakers suitable for sensing and/or pacing cardiac functions are well known in the art. Such devices operate in conjunction with electrode leads which have a distal end that is implanted in the tissue that is to be sensed or paced, and a proximal end that is connected to the pacemaker. Specifically, the proximal end is typically coupled to a terminal provided on the pacemaker so that electrical connection may be made between the electrode lead and circuitry within the pacemaker.
A number of concerns arise regarding the coupling between the pacemaker terminal and the electrode lead. In addition to desiring electrical connection between the two structures, it is important to ensure secure mechanical connection so that the lead does not become dislodged or disconnected from the terminal. Other concerns relate to providing a connector arrangement which is convenient to use so that the physician performing implantation of the pacemaker does not have difficulties in successfully connecting the electrode lead to the pacemaker terminal.
Various arrangements for connecting the electrode lead to the pacemaker terminal have been proposed and used in the art. U.S. Pat. No. 4,540,236 to Peers-Trevarton has a comprehensive review of the different types of lead electrode to pacemaker terminal connections that have been used, and deals not only with electrical connection but also mechanical connection and sealing arrangements. Another Peers-Trevarton patent, U.S. Pat. No. 4,469,104, discloses a connector assembly incorporated into the electrodes of a multi-conductor lead which utilizes resiliant conductive rings.
Other known connection methods utilize a grub screw provided perpendicularly to the electrode lead in order to secure the lead in place in a pacemaker terminal. An example of such an arrangement is disclosed in U.S. Pat. No. 4,445,511 to Cowdery et al.
Many of these different connection arrangements do not fully satisfy the various concerns outlined above, however. Some of the arrangements are complicated to manufacture or are inconvenient to use. Others require more space than is available in modern pacemakers, particularly pacers having relatively thin dimensions. Accordingly, a need still exists for a connection arrangement that is responsive to the various concerns associated with impantation or explantation of pacemakers.

Electrical connector between electrode leads and pacemaker terminal


A method for manufacturing a touch screen panel includes forming first and second conductive layers on a substrate, forming a photosensitive layer on the second conductive layer, exposing the photosensitive layer using a first mask having a first light shielding pattern that corresponds to sensing electrodes and lines to be formed, removing the photosensitive layer at the first exposed portion, sequentially removing the second and first conductive layers at the first exposed portion using the first remaining photosensitive layer as a mask, exposing the photosensitive layer using a second mask having a second light shielding pattern that corresponds to the lines to be formed, removing the photosensitive layer at the second exposed portion, removing the second conductive layer at the second exposed portion using the second remaining photosensitive layer as a mask, thereby forming the sensing electrodes and the lines, and removing the second remaining photosensitive layer.

1. Field
Embodiments relate to a method for manufacturing a touch screen panel.
2. Description of the Related Art
In recent years, touch screen panels have been applied to liquid crystal display devices (LCDs) and organic light emitting display devices (OLEDs). A touch screen panel is a device which allows a user to input a command by contacting the touch screen panel with an object such as a user's hand or pen. The touch screen panel recognizes a contact position by sensing a change in capacitance or voltage between two electrodes, and provides a user's command according to the contact position to a display device.

Method for manufacturing touch screen panel


Provided are a method of testing semiconductor device and a system for testing semiconductor device. The method includes measuring a minimum operating voltage of each of a plurality of sample semiconductor devices and an operating frequency of corresponding ring oscillators included in each of the plurality of sample semiconductor devices, generating a model between the operating frequencies of the ring oscillators and the minimum operating voltages of the sample semiconductor devices, measuring an operating frequency of ring oscillators included in a target semiconductor device, and determining a target minimum operating voltage of the target semiconductor device based on the operating frequency of the ring oscillators of the target semiconductor device and the model.

1. Field of the Disclosure
The present disclosure relates to a method of testing a semiconductor device and a system for testing a semiconductor device. More specifically, the present disclosure relates to a method of testing a semiconductor device using a model generated between the minimum operating voltages of semiconductor chips and the operating frequencies of corresponding ring oscillators included in the semiconductor chips, and a system for testing a semiconductor device using the method.
2. Description of the Related Art
After semiconductor devices have been fabricated, the semiconductor devices undergo various tests in order to ensure operational reliability. A number of operating parameters are set based on results of such tests. The type and number of such tests tends to increase to cope with various environmental variables that are expected in the operation of semiconductor devices. Therefore, in testing a semiconductor device, it is essential to increase test speed and throughput by using an efficient test method.
The above-mentioned operating parameters may have certain correlations among them. By utilizing such correlations, it may be possible to predict the tendency of an operating parameter by measuring another operating parameter. This may be used to improve the test speed and throughput of semiconductor devices.

Method of testing semiconductor devices and system for testing semiconductor devices


A method of emulating a circuit design using an emulator is presented. The method includes allocating one or more spare routing resources to one or more field programmable gate array (FPGA) routing sockets when compiling a plurality of FPGAs disposed in the emulator in preparation for emulating the circuit design, and using the one or more spare routing resources to provide one or more routings among the FPGAs in response to one or more changes made to the circuit design.

The present invention relates generally to a computer implemented method and system for emulating a design and in particular to emulating a design using a multitude of FPGAs with faster emulation implementation when the design is changed.
A field programmable gate array provides a multitude of programmable logic circuits that may be configured to emulate a circuit design, hereinafter also referred to as "design under test (DUT)", at higher speed than computer based simulation. Emulation thus provides a way to validate the interface of a circuit design with hardware peripherals such as through a universal serial bus (USB) emulated on the FPGA that may be difficult to test using slower running computer simulation. A compiler software program translates a DUT's representation, such as hardware description language (HDL), netlist, or other description into one or more bitstreams, which may then be loaded into one or more FPGAs to configure the FPGAs to emulate the circuit. The FPGAs may then emulate the logic functions of the DUT in logic circuits on the FPGAs.
For complex circuit designs, the compiler software typically partitions the DUT into a multitude of FPGAs on a printed circuit board, which includes wiring or nets that provide the interconnect between the FPGAs. The compiler program accesses data representing the DUT's circuits, the DUT's speed constraints, and the available FPGA resources in order to partition the design transparently from the perspective of the DUT designer. Compiling an FPGA may thus be quite time consuming, for example, taking many hours, which may create schedule delays for making even minor changes during design.


Hot air, flowing from the register of a hot air heating system, is conducted through a piping system having vertical conduits communicating with the interior of wet or damp footwear to be dried. The tops of the vertical conduits are provided with 45.degree. elbows to direct the hot air into the toe regions of the footwear.

1. Field of the Invention
This invention relates, broadly speaking, to apparatus for drying wet or damp footwear.
More particularly, this invention relates to apparatus for drying wet or damp footwear from the inside, utilizing hot air flowing from conventional registers of hot air heating systems
2. Description of the Prior Art
Many arrangements are known for drying wet or damp foot-wear. None are known to the inventors for drying wet or damp footwear from the inside, particularly in the toe area, utilizing hot air flowing from conventional registers of hot air heating systems.