An error detector at a receiver comprises a feedback shift register. A shift direction in the feedback shift register is opposite to a shift direction at a transmitter in generating a transmission bit string by using a specified generator polynomial. A reception bit string is inputted to the feedback shift register in reverse order to the transmission bit string generated at the transmitter so that errors in the reception bit string are detected by obtaining the remainder. Another error detector at a receiver comprises first and second feedback shift registers. Respective shift directions in the first and second feedback shift registers are the same as and opposite to a shift direction at a transmitter in generating a transmission bit string. The reception bit string is inputted to the first feedback shift register in the same order in which the transmission bit string was generated, while the reception bit string is inputted to the second feedback shift register in reverse order to one which the transmission bit string was generated. Errors in the reception bit string are detected by comparing respective remainders obtained by the first and second feedback shift registers. This reduces the processing time required for the error detection and increases efficiency in detecting errors in transmitted data.

1. Field of the Invention
The present invention relates to a detection of errors in data and, more particularly, to an error detector for detecting errors that occur in data under transmission.
The present invention relates to a semiconductor device comprising the error detector.
The present invention relates to an error detection method for detecting errors that occur in data under transmission.
2. Description of the Related Art
There are various factors which may cause errors in data being transmitted via transmission lines. For the detecting the errors, a transmitter in a communication system adds check data, under a given rule, to target data to be transmitted. A receiver in the communication system examines whether or not the transmitted data is in accordance with the rule and judges whether or not there are the presence of errors based on the result of the detection.
Out of error detection methods, the most prevalent one is a CRC (Cyclic Redundancy Check) method using a cyclic code. In the CRC error detection, the transmitter splits the target data to be transmitted into information bit strings of a specified length, represents each of the information bit strings in a polynomial, and divides it by a generator polynomial. The transmitter then generates the cyclic code by adding, as check bits, a remainder from the division to the information bit string and transmits the cyclic code to the receiver.
The receiver divides the received cyclic code by the same generator polynomial used at the transmitter to judge whether or not the presence of errors depending on whether or not the cyclic code is divisible.
FIG. 1 shows an exemplary communication system that performs the error detection by using the cyclic code. In the communication system, a transmitter 1, and a receiver 2 are connected to each other via a radio transmission line 3. The transmitter 1 and the receiver 2 correspond to, e.g., a base station and a mobile terminal for mobile communication such as a mobile phone, respectively.
The transmitter 1 has a coder 4 for coding data to be transmitted and a data modulating/transmitting unit 5 for modulating the coded data and outputting the modulated data to the radio transmission line 3. The coder 4 is composed of a feedback shift register 6.
The receiver 2 has a data receiving/demodulating unit 7 for receiving the data transmitted via the radio transmission line 3 and demodulating the received data, and an error detector 8 for detecting errors in the demodulated data. The error detector 8 is composed of a feedback shift register 9 and an right/wrong output unit 10 for outputting an error detecting signal FLAG. The error detector 8 has been formed in a semiconductor device SEM with other communication functional elements.
As shown in FIG. 2, the feedback shift register 6 and the feedback shift register 9 are composed of identical circuits such as dividers conforming to a sixteenth-degree generator polynomial X16+X12+X5+1.
Each of the feedback shift registers 6 and 9 has a register unit 11 consisting of flip-flop circuits X15 to X0 (hereinafter referred to as F/F circuits X15 to X0) connected in cascade, three EOR (Exclusive OR) circuits 12a, 12b, and 12c, and switches S1 and S2. In the register unit 11, a shift direction has been set such that data is shifted from the F/F circuit X0 to the F/F circuit X15. A clock signal CLK is connected to the clock terminal of each of the F/F circuits X15 to X0 such that shift operations are performed in synchronization.
The EOR circuit 12a receives an output of the F/F circuit X15 and an input signal DIN1 (or DIN2) and outputs the result of the operation to the F/F circuit X0. The EOR circuit 12b receives the output of the EOR circuit 12a and an output of the F/F circuit X11 and outputs the result of the operation to the F/F circuit X12. The EOR circuit 12c receives the output of the EOR circuit 12a and an output of the F/F circuit X4 and outputs the result of the operation to the F/F circuit X5.
The switch S1 is for selectively connecting the output of the F/F circuit X15 or the input signals DIN1 and DIN2 to the output signals DOUT1 and DOUT2 of the feedback shift registers 6 and 9. The switch 2 is for feeding back the output of the EOR circuit 12a to the EOR circuits 12b and 12c and to the F/F circuit X0.
In the communication system shown in FIG. 1, the transmitter 1 performs coding and the receiver 2 performs the error detection as follows. By way of example, the following description will be given to the case where a 6-bit information bit string xe2x80x9c01 0101xe2x80x9d is transmitted.
FIG. 3 shows the respective states of the F/F circuits X15 to X0 when the feedback shift register 6 at the transmitter 1 is operated. Upon each receipt of the clock signal CLK, the feedback shift register 6 shifts the values held by the F/F circuits X15 to X0 to the left in the drawing, so that xe2x80x9cSTATExe2x80x9d is incremented by 1 upon each receipt of the clock signal CLK. That is, the individual F/F circuits X15 to X0 undergo transitions from xe2x80x9cSTATE 0xe2x80x9d to xe2x80x9cSTATE 6xe2x80x9d when viewed in the columnar direction.
In xe2x80x9cSTATE 0xe2x80x9d, each of the F/F circuits X15 to X0 is reset to xe2x80x9c0xe2x80x9d.
In xe2x80x9cSTATE 1xe2x80x9d through xe2x80x9cSTATE 6xe2x80x9d shown in FIG. 2, the switch S1 is switched to connect the input signal DIN1 to the output signal DOUT, and the switch 2 is closed. Consequently, the information bit string xe2x80x9c01 0101xe2x80x9d inputted from the input signal DIN1 is inputted to the feedback shift register 6 and outputted simultaneously to the output signal DOUT1.
The information bit string outputted to the output signal DOUT1 is modulated by the data modulating/transmitting unit 5 and then transmitted to the receiver 2 via the radio transmission line 3.
When the feedback shift register 6 has operated to reach xe2x80x9cSTATE 6xe2x80x9d, the values xe2x80x9c0100 0010 0001 0100xe2x80x9d held by the respective F/F circuits X15 to X0 form a check bit string and the cyclic code xe2x80x9c01 0101 0100 0010 0001 0100xe2x80x9d enclosed in the bold rectangle of FIG. 3 are generated from the information bit string and the check bit string.
An output of the check bit string is performed by operating the feedback shift register 6 and sequentially outputting the values held by the F/F circuits X15 to X0 in xe2x80x9cSTATE 6xe2x80x9d to the output signal DOUT1. At this time, the switch S1 is switched to connect the output of the F/F circuit X15 to the output signal DOUT1, and the switch S2 is open. By opening the switch S2, a xe2x80x9c0xe2x80x9d is inputted to each of the F/F circuit X0 and the EOR circuits 12b and 12c.
The check bit string outputted to the output signal DOUT1 is modulated by the data modulating/transmitting unit 5 and then transmitted to the receiver 2 via the radio transmission line 3.
The data receiving/demodulating unit 7 at the receiver 2 receives the modulated cyclic code (information bit string+check bit string) and sequentially demodulates it to the original cyclic code. The data receiving/demodulating unit 7 inputs the individual bits of the cyclic code to the feedback shift register 9 of the error detector 8 in the order in which they were demodulated.
FIG. 4 shows the respective states of the individual F/F circuits X15 to X0 when the feedback shift register 9 of the error detector 8 is operated. It is to be noted that FIG. 4 shows the operation when the received cyclic code has no error.
In xe2x80x9cSTATE 0xe2x80x9d, each of the F/F circuits X15 to X0 is reset to xe2x80x9c0xe2x80x9d. In xe2x80x9cSTATE 1xe2x80x9d through xe2x80x9cSTATE 22xe2x80x9d, the switch S2 of FIG. 2 is closed. The switch S1 may be switched to either side.
The feedback shift register 9 sequentially receives the cyclic code xe2x80x9c01 0101 0100 0010 0001 0100xe2x80x9d from the input signal DIN2. In xe2x80x9cSTATE 22xe2x80x9d in which the cyclic code has been received up to the least significant bit (hereinafter referred to as LSB) thereof, the values held by the F/F circuits X15 to X0, i.e., the value of the remainder obtained by dividing the received cyclic code by the generator polynomial, is xe2x80x9c0xe2x80x9d when the received data is error-free.
Whether or not the remainder is xe2x80x9c0xe2x80x9d is verified by the right/wrong output unit 10 of FIG. 1. Therefore, the feedback shift register 9 sequentially outputs the values held by the F/F circuits X15 to X0 in xe2x80x9cSTATE 22xe2x80x9d to the output signal DOUT2. At this time, the switch S1 is switched to connect the output of the F/F circuit X15 to the output signal DOUT2, while the switch S2 is open.
The right/wrong output unit 10 sequentially receives from the output signal DOUT2 a 16-bit value, which is the remainder from the division, performs a logical NOR operation with respect to each bit of the received value, and outputs the result of the operation to the error detecting signal FLAG. Accordingly, a xe2x80x9c1xe2x80x9d is outputted to the error detecting signal FLAG if the received cyclic code is correct. If the received cyclic code is erroneous, on the other hand, some of the values held by the F/F circuits X15 to X0 in xe2x80x9cSTATE 22xe2x80x9d shown in FIG. 4 are nonzero. Therefore, a xe2x80x9c0xe2x80x9d is outputted to the error detecting signal FLAG as a result of the NOR operation performed with respect to each of the values held by the F/F circuits X15 to X0. If the error detecting signal FLAG is xe2x80x9c0xe2x80x9d, the receiver 2 discards the received data or gives a retransmission instruction to the transmitter 1.
By thus using the cyclic code, the communication system described above detects errors that have occurred on the data on the radio transmission line 3.
In general, communication systems perform not only the error detection but also the error correction for transmitted data. As an error correcting code for use in the error correction, a block code such as the cyclic code and a convolutional code are known. Since the radio transmission line used in mobile communication or the like has highly variable characteristics depending on geographical features and weather conditions and a burst error due to fading is likely to occur, the convolutional code effective in correcting the burst error is used frequently.
FIG. 5 shows an exemplary communication system that performs the error correction by using the convolutional code. In the communication system, the transmitter 1 has the coder 4, a convolutional coder 13, and the data modulating/transmitting unit 5 which are connected in series, and the receiver 2 has the data receiving/demodulating unit 7, a Viterbi decoder 14, a data processing unit 15, and the error detector 8 which are connected in series. In FIG. 5, the same components as used in FIG. 1 are designated by similar reference numerals.
In the communication system shown in FIG. 5, the detection and correction of errors in data transmitted from the transmitter 1 are performed at the receiver 2.
First, the coder 4 at the transmitter 1 obtains a check bit string from an information bit string to generate a cyclic code and sequentially outputs the cyclic code to the output signal DOUT1 having the information bit string side as the most significant bit (hereinafter referred to as MSB).
The convolutional coder 13 sequentially receives the cyclic code from the MSB side, generates the convolutional code, and outputs the code to the data modulating/transmitting unit 5. The data modulating/transmitting unit 5 modulates the convolutional code and outputs the modulated convolutional code onto the radio transmission line 3.
The data transmitting/demodulating unit 7 at the receiver 2 sequentially receives the modulated convolutional code, demodulates the code to the original convolutional code, and outputs it to the Viterbi decoder 14.
The Viterbi decoder 14 decodes the received convolutional code to the original cyclic code. During decoding, the Viterbi decoder corrects the burst error or the like that has occurred on the radio transmission line 3 to recover the original correct bit string. In the Viterbi decoder 14, the cyclic code is sequentially decoded from the LSB side and outputted.
Next, the cyclic code outputted from the LSB side is sequentially loaded into the data processing unit 15 and, after the reception is completed, the loaded cyclic code is outputted from the MSB side to the input signal DIN2 of the feedback shift register 9. Thereafter, the error detection is performed similarly to that performed by the communication system of FIG. 1 described above and the result of the detection is outputted as the error detecting signal FLAG.
To perform the error detection at the receiver 2 in the communication system shown in FIG. 1, all the bits of the cyclic code should be inputted bit by bit to the error detector 8. If the information bit string has considerable bit length, an increased processing time is required for the error detection, leading to the problem that the error detection process cannot be performed efficiently.
In the communication system shown in FIG. 5, the Viterbi decoder 1 at the receiver 2 decodes the cyclic code from the LSB side. The feedback shift register 9 receives the cyclic code from the MSB side to perform the error detection. Consequently, the receiver 2 cannot output the cyclic code sequentially decoded by the Viterbi decoder 14 directly to the feedback shift register 9.
As a result, the entire cyclic code should preliminarily be inputted from the LSB side to the data processing unit 15 and, after the decoding process by the Viterbi decoder 14 is completed, the cyclic code is finally outputted from the MSB side to the feedback shift register 9.
This causes the problems of the processing time extending from the decoding process to the error detection increasing and the circuit scale increasing.
The increased circuit scale further causes the problem that the chip size of the semiconductor device SEM increases when the error detector 8 has been formed into the semiconductor device SEM.
Since the error detection cannot be performed efficiently, there is the possibility that data transmission efficiency in the communication system is lowered.
It is an object of the present invention, having been made in order to solve the problems described above, to provide an error detector and an error detection method wherein the processing time for error detection can be reduced and errors in transmitted data can be detected efficiently.
Another object of the present invention is to provide a semiconductor device comprising the error detector wherein the error detection can be performed efficiently without increasing the chip size.
Still another object of the present invention is to provide a communication system wherein the error detection can be performed without lowering the efficiency of data transmission on a transmission line.
In the error detector according to the present invention, a feedback shift register for dividing a reception bit string by a generator polynomial is so constructed that a shift direction and a feedback direction in obtaining a remainder thereby are opposite to a shift direction and a feedback direction at a transmitter in generating a transmission bit string by using a specified generator polynomial. Accordingly, the reception bit string is sequentially divided to generate the remainder by inputting the reception bit string to the feedback shift register in reverse order to the transmission bit string was generated at the transmitter. Errors in the reception bit string are detected based on the remainder. This reduces processing time required for the error detection and provides efficient error detection process in the case where the reception bit string is inputted in reverse order to the order the transmission bit string was generated at the transmitter.
In one of the aspects of the present invention, in the error detector, the feedback shift register also comprises: a register unit having stages equal in number to the highest degree of the specified generator polynomial; the first operation unit for performing an operation between an input value to the register unit and an output value from the final stage and outputting a result of the operation to the first stage; and the second operation unit for performing an operation between the output value from the final stage and an output value from the stage equal in number to the degree of each of the terms of the specified generator polynomial other than the highest-degree and lowest-degree terms and outputting a result of the operation to the next stage. Accordingly, the value of the register unit of the feedback shift register in each state is changed to the direction that returns the check bit string generated by the feedback shift register at the transmitter to an initial value, by causing the feedback shift register to perform shift operations and inputting the reception bit string thereto in reverse order of the transmission bit string generated. As a result, the reception bit string can be judged to be erroneous if the value of the register unit when the feedback shift register has performed a specified number of shift operations does not coincide with the initial value of the feedback shift register at the transmitter.
In another aspect of the present invention, the error detector comprises comparing unit for comparing the remainder obtained by the feedback shift register with a predetermined expected value and outputting error data indicative of the dissimilarity as a result of the comparison. This result of the comparison performed by the comparing unit allows easy the error detection. The remainder may be compared bit by bit with the expected value, while causing the feedback shift register performs shift operations, or alternatively, all the bits of the remainder may be compared at a time with the expected value by constructing the feedback shift register such that the generated remainder is outputted in parallel.
In yet another aspect of the present invention, the error detector comprises an initializing unit for initializing the register unit of the feedback shift register. This allows initialization of the register unit without causing the feedback shift register to perform shift operations. As a result, the register unit is loaded with the remainder (check bit string) of the reception bit string, which was generated at the transmitter, by merely causing the feedback shift register to perform shift operations after the initialization. The reason why the reception of the check bit string by the register unit is possible by mere shift operations is that each of the first and second operation units has an input connected to the final stage of the register unit. When the register unit is initialized, therefore, data inputted to the feedback shift register is sequentially loaded therein till it makes a complete circulation around the register unit.
In still another aspect of the present invention, the error detector comprises a specified value setting unit for setting a specified value to the register unit of the feedback shift register. The arrangement allows the remainder (check bit string) obtained at the transmitter to be loaded simultaneously into the register unit without causing the feedback shift register to perform shift operations.
In another aspect of the present invention, the error detector comprises the first and second feedback shift registers. The shift direction and the feedback direction in the first feedback shift register are the same as the shift direction and the feedback direction at a transmitter in generating a transmission bit string by using a specified generator polynomial. A shift direction and a feedback direction in the second feedback shift register are opposite to the shift direction and feedback direction at the transmitter in generating the transmission bit string by using the specified generator polynomial. The first feedback shift register generates a remainder by receiving a reception bit string in the same order in which the transmission bit string was generated at the transmitter and dividing the reception bit string. The second feedback shift register generates a remainder by receiving the reception bit string in reverse order to the transmission bit string was generated at the transmitter and dividing the reception bit string. The error detector detects errors in the reception bit string based on an agreement or a disagreement between the respective remainders obtained by the first and second shift registers.
In still another aspect of the present invention, in the error detector, the first feedback shift register comprises: a first register unit having stages equal in number to the highest degree of the specified generator polynomial; the first operation unit for performing an operation between an input value to the first register unit and an output value from the final stage and outputting a result of the operation to the first stage; and a second operation unit for performing an operation between the result of the operation performed by the first operation unit and an output value from the stage which is smaller by one ordinal number than the degree of each of the terms of the specified generator polynomial other than the highest-degree and lowest-degree terms. The second feedback shift register comprises: a second register unit having stages equal in number to the highest degree of the specified generator polynomial; a third operation unit for performing an operation between an input value to the second register unit and an output value from the final stage and outputting a result of the operation to the first stage; and a fourth operation unit for performing an operation between the output value from the final stage and an output value from the stage corresponding to the degree of each of the terms of the specified generator polynomial other than the highest-degree and lowest-degree terms and outputting a result of each operation to the subsequent stage.
As a result, the value of the first register unit of the first feedback shift register in each state is changed in the same direction as when the feedback shift register at the transmitter performed shift operations by causing the first feedback shift register to perform shift operations and inputting the reception bit string thereto in the same order in which the transmission bit string was generated at the transmitter. The value of the second register unit of the second feedback shift register in each state is changed in the direction that returns the check bit string generated by the feedback shift register at the transmitter to the initial value, by causing the second feedback shift register to perform shift operations and inputting the reception bit string thereto in reverse order to the transmission bit string was generated at the transmitter. If the reception bit string has no errors, the value of the first register unit and the value of the second register unit coincide with each other when each of the first and second feedback shift registers performs shift operations. Whether errors in the reception bit string is present or not is detected based on an disagreement or agreement between the respective remainders obtained by the first and second feedback shift registers.
In still another aspect of the present invention, the error detector comprises comparing unit for comparing the respective remainders obtained by the first and second feedback shift registers and outputting error data indicative of a dissimilarity as a result of the comparison. The arrangement allows the error detection based on the result of the comparison performed by the comparing unit.
In still another aspect of the present invention, the error detector comprises specified value setting unit for setting a specified value to each of the first and second feedback shift registers. The arrangement allows the setting of a specified value to each of the first and second registers without causing the first and second feedback shift registers to perform shift operations.
In one of the aspects of the present invention, in the semiconductor device, each of the foregoing error detectors can be composed of an error detector formed in the semiconductor device with other communication functional elements without increasing the manufacturing cost. Since the feedback shift register composing the error detector has been constructed by merely reversing the shift direction and the feedback direction of the feedback shift register at the transmitter, if the conventional semiconductor device has a feedback shift register of the same construction as that of the feedback shift register at the transmitter, the semiconductor device comprising a feedback shift register which is opposite in shift direction and in feedback direction can be formed easily by merely changing a mask for the wiring layer of the semiconductor device and changing the wiring of the feedback shift register. In this case, there is no need to change the chip size and pad position of the semiconductor device and any changes do not influence on exterior of the semiconductor device.
In one of the aspects of the present invention, in the error detection method, the inputting of a reception bit string to a division procedure using a specified generator polynomial as a divisor is performed in an order reverse to the order in which the transmission bit string was generated at the transmitter by using the generator polynomial. Errors in the reception bit string are detected based on the obtained remainder, which reduces the processing time required for the error detection.
In another aspect of the present invention, in the error detection method, the remainder from the division procedure is compared with a predetermined expected value, the reception bit string is judged to be erroneous when the result of the comparison indicates a dissimilarity therebetween, so that the processing time required for the error detection is reduced.
In yet another aspect of the present invention, in the error detection method, a buffer unit for receiving the remainder from the division procedure is initialized before the division procedure is executed, which reduces the processing time required for the error detection.
In still another aspect of the present invention, in the error detection method, a buffer unit for receiving the remainder from the division procedure is set to a specified value before the division procedure is executed, which reduces the processing time required for the error detection.
In still another aspect of the present invention, in the error detection method, the first and second division procedures each for dividing a reception bit string by a specified generator polynomial are provided. The inputting of the reception bit string to the first division procedure is performed in the same order in which a transmission bit string is generated by using the generator polynomial at the transmitter. On the other hand, the inputting of the reception bit string to the second division procedure is performed in an order reverse to the order in which the transmission bit string is generated by using the generator polynomial at the transmitter. The respective remainders from the first and second division procedures are compared and the reception bit string is judged to be erroneous when the result of the comparison indicates a dissimilarity therebetween.
In another aspect of the present invention, in the error detection method, each of the first buffer unit for receiving the remainder from the first division procedure and the second buffer unit for receiving the remainder from the second division procedure is set to a specified value before the first and second division procedures are executed, so that the processing time required for the error detection is reduced.

Error detector, semiconductor device, and error detection method


Examples are disclosed that relate to the use of an always-depleted photodiode in a ToF depth image sensor. One example provides a method of operating a pixel of a depth image sensor, the method comprising receiving photons in a photocharge generation region of the pixel, the photocharge generation region of the pixel comprising an always-depleted photodiode formed by a doped first region comprising one of p-doping or n-doping and a more lightly-doped second region comprising the other of p-doping or n-doping. The method further comprises, during an integration phase, energizing a clock gate for a pixel tap, thereby directing photocharge generated in the photocharge generation region to an in-pixel storage comprising a capacitor, and in a readout phase, reading charge out from the in-pixel storage.

Time-of-flight (ToF) cameras determine depth by measuring the round-trip travel time for light between the camera and an object. In some ToF cameras, a temporally-modulated illumination light signal illuminates a scene, and image sensor pixels capture phase information for the reflected illumination light, from which a distance value is calculated for each pixel.

Depth image sensor with always-depleted photodiodes


Provided are a system and method of clustering documents. The system includes a document DB, a document feature writing unit storing documents, a document retrieving unit, a clustering unit, and a cluster DB. The document DB stores documents. The document feature writing unit extracts attribute information of documents stored in the document database, and writes indexes with respect to the respective documents on the basis of the attribute information. The document retrieving unit retrieves documents including a query input by a user, using the indexes. The clustering unit includes a representative vector calculator calculating feature vectors and a representative vector of the retrieved documents, and a similarity calculator calculating similarities between the documents using the feature vectors and the representative vector. The cluster database stores documents clustered by the clustering unit.

1. Field of the Invention
The present invention relates to a system and method of clustering documents capable of determining a similarity between documents, and clustering similar documents on the basis of the determined similarity.
2. Description of the Related Art
Recently, a document retrieval system has been widely used, which processes countless document information, extracts information corresponding to user demand, and provides the extracted information to a user.
That is, document retrieval or information retrieval refers to searching for documents or information desired by a user from bulk documents or information. To retrieve documents or information, keyword processing is performed with respect to natural language texts, a weight is assigned to each keyword, and then retrieval and ordering are conducted.
The related art document retrieval system receives a query of a user, and outputs a common result extracted by a common system to the user. Here, a general retrieval system searches documents only on the basis of an area of the query received from the user, and thus it is difficult to provide the user with information characterized according to user's tastes and characters.
Also, since the related art retrieval system searches for information regarding just the query input by the user, a wrong retrieval range may be established. For this reason, information desired by the user and retrieval results show much difference, causing accuracy and reliability of retrieval results to degrade.
In addition, when receiving a query from a user, the related art document retrieval system performs an operation depending on a retrieval system used by sites providing information. Hence, accuracy of retrieved information is lowered, and it becomes difficult to provide information in real-time. However, in the case of documents that must be retrieved right after its generation or before a long time is elapsed after its generation, such as patent documents, a document accessing method and a search method characterized for a user are being required.

System and method for clustering documents


The present invention concerns a transmitting device adapted to send content in bursts in a channel, the channel comprising a plurality of bursts, wherein a burst comprises at least one time slot. The transmitting device comprises first communicating means for receiving content from a first network, second communicating means for sending the content to a second network, the content being successively sent over at least one time slot of the bursts of the channel, time slot means for assigning a channel, and at least one unfilled time slot in the bursts of the channel to at least one second transmitting device located on the second network and signaling means for indicating the channel and the unfilled time slots to the at least one second transmitting device.

This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
The Digital Video Broadcasting-Terrestrial, noted DVB-T, is a standard for the transmission of digital terrestrial television. It is specified in the standard document ETSI EN 300 744: "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for digital terrestrial television (DVB-T)".
Within the digital terrestrial TV context, DVB-H is a DVB-T extension for broadcast services distribution to mobile terminals, also called handheld terminals. DVB-H mainly defines means for reducing power consumption and increasing reliability. It is specified in the standard document ETSI EN 302 304 V1.1.1 (2004 November) "Digital Video Broadcasting (DVB); Transmission System for Handheld Terminals (DVB-H)". A difference brought by DVB-H over DVB-T is the fact that video and audio are transported in Internet Protocol packets, IP packets. The payload of DVB-H is constituted of IP datagram or other network layer datagram encapsulated into MultiProtocol Encapsulation sections. DVB-H introduces time-slicing in order to reduce the average power consumption of the terminal and to enable smooth and seamless frequency handover.
The time slicing technique is further described in ETSI standard, EN 301 192 V1.4.1 (2004 November) "Digital Video Broadcasting (DVB); DVB specification for data broadcasting". With the time-slicing mechanism the sender sends a burst using the highest possible bit rate to multiple receivers. Time-slicing consists in sending data in bursts using higher instantaneous bit rate compared to the bit rate required if the data were transmitted using traditional streaming mechanisms. A burst comprises multiple sections. To indicate to the receiver when to expect the next burst, the time to the beginning of the next burst, which is the delta-t, is indicated in each section of the burst.
Time-slicing enables a receiver to stay active only a fraction of the time, while receiving bursts of a requested service. Between bursts belonging to the same service/stream, a DVB-H receiver may switch off its reception unit in order to save power. Once tuned to a TV service for instance, a terminal saves up to eighty percent of power as compared to a DVB-T tuner where the reception unit is continuously on. The set of time-sliced bursts is referred to a DVB-H channel hereinafter. Time slicing then enables a receiver to select a DVB-H channel for receiving a service, and not to listen to the other DVB-H channels.
Increasing reliability is done using a Forward Error Correction (FEC) mechanism. Each service, such as video service, is associated to one section whereas the service guide information, metadata, may be sent through a dedicated section. The device that transmits content using the time slicing and FEC techniques is called an IP Encapsulator (IPE).
The FIG. 1 represents a DVB-H distribution system, compliant with the ETSI TR 102 469 V1.1.1 (2006 May), "Digital Video Broadcasting (DVB); IP Datacast over DVB-H: Architecture". It comprises a video content server 1 and a DVB-H IP Encapsulator (IPE) 2. The video content server is connected to the IPE in a manner well known to the skilled in the art of the DVB-H distribution system. The IPE sends the DVB-H content to the regional DVB-H transmission system 4 through the DVB-H distribution network 3. Only one IPE serves the entire network. The IPE is generally located in a national head-end office. Every DVB-H service is generated from this IPE including regional or local services.
An alternative DVB-H distribution system, not represented and described in the white paper "DVB-H Mobile TV flexible satellite distribution, UDcast, January 2007", is based on several IPEs distributed over a set of regional areas. The same content, under the form of IP streams, is sent to all IPEs that generate DVB-H stream locally. This requires a unique management system to synchronize all IPEs together. All the IPEs distribute the same content locally.
These two architectures are not optimized. Either it requires sending all the content and services to the centralized IPE before being distributed. Or, with a regional distribution, it is very difficult to have a synchronized national network. In any case, it is not possible to modify the DVB-H stream once it has been generated at the IPE.

System and devices for distributing content in a hierarchical manner


A fixing structure for a vertical tap includes a vertical tap, a mounting member, a fitting member, a fixing ring, and a decorative loop. The mounting member secured in the ground includes a receiving chamber arranged on the top thereof and has two retaining tabs aft ached on the upper end thereof. The upper end of the fitting member screws with the lower end of the vertical tap. The fitting member includes two opposite fastening projections disposed on the outer periphery at the lower end thereof and extending outwardly therefrom. The fixing ring is fitted onto the external rim of the vertical tap, is then secured in a wooden floor by using a number of wood screws, and is further engaged with the internal rim of the vertical tap by way of a bolt. The decorative loop covers the fixing ring, thereby supporting and securing the vertical tap easily.

1. Field of the Invention
The present invention relates to a fixing structure and, more particularly, to a fixing structure for a vertical tap that may effectively and easily secure the vertical tap.
2. Description of the Prior Arts
As shown in FIGS. 1 and 2, a conventional fixing structure for a vertical tap includes a vertical tap 10, the bottom of which is directly affixed to a wooden floor A by using a screwing seat 20. In assembly, external threads 201 of the screwing seat 20 are screwed with internal threads 101 of the bottom of the vertical tap 10, and a plurality of wood screws 30 are inserted through a number of predetermined through holes 202 of the screwing seat 20. Thus, the vertical tap 10 may be locked in the wooden floor A.
Nevertheless, such a conventional fixing structure may have a disengagement of the vertical tap 10 from the wooden floor A, because the vertical tap 10 is simply screwed with the screwing seat 20 together. Furthermore, in order to align an outlet pipe of the vertical tap 10 with the bathtub, the vertical tap 10 has to be further fixed by virtue of the wood screws 30 after being positioned, causing an inconvenient assembly.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.


A process of the production of a product of interest in an F1 seed obtained by a hybridization of a first and a second transgenic parental plant, said hybridization generating a genetic endowment in said F1 seed for said production by combining in said F1 seed first and second partial genetic endowments of said first and second transgenic parental plants, followed by isolating said product of interest from said F1 seed or a seedling thereof.

The major problems of current genetic engineering processes of plants can be summarized as follows:    1. Generally low yield of the product of interest. Examples are pharmaceutical proteins, enzymes, other proteins, polymers, sugars, polysaccharides, etc. Low yield means high purification/downstream processing costs.    2. Genetic contamination due to free crossing of genetically modified plants with non-transgenic varieties or wild relatives as well as presence of "volunteer" plants in the fields following the harvest. Such events easily occur spontaneously because plants are self-replicating organisms or because of human mistakes or deliberate actions.
Both problems are to a great degree flip sides of the same problem: low yield is usually a result of our desire to construct a plant that is a producer which at the same time retains an ability of going through a full development and reproduction cycle. Combining the process of development and reproduction with the process of transgene expression does not give a solution. Inducible (U.S. Pat. Nos. 5,187,287; 5,847,102; Mett et al., 1993, Proc. Natl. Acad. Sci., 90, 4567-4571; Aoyama & Chua, 1997, Plant J., 11, 605-612; McNellis et al., 1998, Plant J., 14, 247-257; U.S. Pat. No. 6,063,985; Caddick et al., 1997, Nature Biotech., 16, 177-180; WO09321334; Weinmann et al., 1994, Plant J., 5, 559-569) or organ-specific transgene expression systems (U.S. Pat. No. 5,955,361; WO09828431; De Jaeger et al., 2002, Nature Biotech., 20, 1265-1268) do also not provide a solution to the problem of genetic contamination and do not provide for high yield of the product of interest. All inducible and tissue-specific promoters used in the systems mentioned above have basal activity, e.g. they are "leaky", which in the course of generations causes transgene silencing, thus inevitably decreasing the yield of the product of interest. Moreover, the yield is not the only problem, as transgenic plants carrying recombinant genes under control of such inducible systems do not fulfill stringent biosafety criteria, for example in the case of production of recombinant biopharmaceuticals.
The use of amplification vectors based on plant viral elements can potentially provide a partial solution to the mentioned problems, especially when such vectors are used for transient expression (U.S. Pat. Nos. 5,491,076; 5,977,438; 5,316,931; 5,589,367; 5,866,785; WO0229068). However, most of the vectors for transient expression experiments were developed for selected plant species, predominatly of the Nicotiana family (U.S. Pat. Nos. 5,466,788; 5,670,353; 5,866,785; WO02088369). The efficiency of viral vectors for the production of recombinant protein/RNA of interest is also determined by their ability for efficient cell-to cell and systemic movement. The latter parameters are species- and variety dependent, thus severely restricting the freedom to choose hosts for transient expression. A potential solution to this problem is the design of transgenic plants carrying the viral vector stably integrated into the chromosomal DNA. The use of viral vectors designed for the expression of foreign sequences in plants via transfection or stable incorporation into the plant chromosomal DNA was described in numerous reviews (Stanley, J., 1993, Curr Opin Genet Dev., 3, 91-96; Schlesinger, S. 1995, Mol Biotechnol., 3, 155-165; Porta, C. & Lomonossoff, G. 2002, Biotechnol. & Genel. Eng. Rev., 19, 245-291; Awram et al., 2002 Adv Virus Res., 58, 81-124). However, attempts to design transgenic plants with an amplicon vector stably integrated into the chromosomal DNA usually faces the problem of transgene silencing, thus turning this approach useless. In the best case, it provides a yield that is slightly higher than that provided by a strong constitutive promoter, as was shown in late 80s by Hayes and colleagues for GUS and NPT genes (Hayes et al., 1989, Nucl. Acids Res., 17, 2391-2403). Since that time there was no significant breakthrough in achieving high yield, biologically safe recombinant protein production in transgenic plants based on viral replicons.
The work of Mallory and colleagues (2002, Nature Biotechnol., 20, 622-625) on amplicons in hybrid plants, whereby said hybrid plants provide for a suppressor of post-transcriptional gene silencing (PTGS), offers a partial solution to the problem. However, this approach did not give a high yield of the product of interest, that is incompatible with normal plant development. Further, biosafety issues were not addressed. Gooding and colleagues (1999, Nucleic Acids Res., 27, 1709-1718) reported replication of geminiviral vectors in isolated wheat embryos in a scientific study. Possible technical applications were not addressed. Further, this method cannot be scaled up and is therefore of no use for technical applications.
It is therefore an object of the invention to provide a novel process of producing a product of interest like a protein of interest in a plant production system, notably in high yield. It is another object of the invention to provide a biologically safe process of producing a product of interest, notably a protein of interest, in a plant production system, whereby distribution in the environment of transgenic genetic material involved in said process is tightly controlled and occurs with low probability. It is a further object of the invenion to provide a process of producing a product of interest like a protein of interest in a plant production system, whereby plant growth and isolation of the product of interest can be decoupled in space and time without loosing yield or quality of said product of interest.

Safe production of a product of interest in hybrid seeds


A concealed joint construction system for installing and securing sheet material such as laminated plastic wall boards, plywood and the like for finishing off bathtub and/or shower walls, counter-tops and back-splashes, and the like. The joint construction system includes an extending channel attached to one wallboard via multiple teeth sunk into matching grooves cut out of the wallboards edge. An adjacent wallboard can be easily and quickly inserted into the extending channel and is secured by pressure flanges perforated from the wall of the channel. The joint construction system is easily installed, secure, and compact, and is completely invisible after installation.

A list of prior patents which may be of interest is provided below:
______________________________________ U.S. Pat. No. Inventor Issue Date ______________________________________ 1,165,413 Jester DEC 28 1915 3,528,559 Miller SEP 15 1970 3,688,459 Mattix SEP 05 1972 3,789,568 Mattix FEB 05 1974 3,811,241 Mattix MAY 21 1974 3,966,705 Gutierrez DEC 14 1976 4,865,066 Brooks SEP 12 1989 5,228,249 Campbell JUL 20 1993 ______________________________________
The use of plastic laminated wallboards and the like for finishing of counter-tops and back-splashes and shower and bathtub installations in place of ceramic tiles has been common.
Various means of installing the wallboards and fixing them in place have been taught. However, until the joint construction and installation system of the Mattix patent (U.S. Pat. No. 3,688,459), all such prior art systems have various distinct disadvantages such as clumsiness, bulk, unattractiveness, visibility, a lack of security, expense, have leakage problems, are unduly time consuming, or require some degree of skill to obtain exact alignment. Nor have they been easily adaptable to both the counter-top/back-splash and shower/bathtub applications.
Examples of such prior art systems are the U.S. patents to Anglinetti, U.S. Pat. No. 3,420,021; Wilhoyte, U.S. Pat. No. 2,218,273; McBride, U.S. Pat. No. 3,277,617; Hobbs, U.S. Pat. No. 2,677,268; Sperry, U.S. Pat. No. 2,219,714; Gregoire, U.S. Pat. No. 3,376,679; and Schmitt, U.S. Pat. No. 1,672,914.
In the Mattix Pat. No. 3,688,459, although its disclosure provided quite a substantial advance in the art at its time, its approach also needed improvement. In particular, a rabbet or rectangular cut-out is required in the method of attaching the corner lock clip to a wallboard is rather unsophisticated and allows room for error in the exact alignment of the wallboards. In addition, in order to insert a second panel into the clip secured to a first panel, a rectangular cut-out must be made to prevent the clip from adding bulk to the comer. Nor are the lengths of the clip when installed precisely determined due to their angled orientation prior to the insertion of the second panel. This makes measuring the exact width of the panels and cut-out more difficult thereby making a tight and secure comer more difficult to achieve.

Joint construction and panel installation system


Gas separation membranes are provided and more particularly, a series of addition-type and ROMP type polynorbornenes with substituents derived from Mizoroki-Heck reactions are provided and have particular utility as gas separation membranes for natural gas upgrading.

Natural gas (methane) is often found with substantial amounts of impurities that must be removed before pipeline distribution. Heavy hydrocarbon components, such as propane and butane, are valuable for energy production or chemicals manufacturing. Currently, hydrocarbons such as propane and butane are removed from natural gas by refrigeration technologies that condense these products out as liquids, where they are separated from natural gas. While effective, refrigeration technologies are relatively expensive and energetically intensive. An alternative technology to separate propane and butane from natural gas uses semipermeable polymeric membranes, which do not require costly cooling mechanisms and have a "free" energetic driving force—the high pressure/concentration gas feed.
Many gas separation membranes have been developed and commercialized to separate nitrogen from air, carbon dioxide from methane, and several other gas pairs. These membranes operate on the basis of diffusion selectivity, where smaller molecules permeate at a faster rate through the polymeric membrane. If these processes were applied towards the separation of propane and butane from methane, methane would permeate at a faster rate than propane or butane, which would necessitate costly recompression of the methane permeate before pipeline distribution. Therefore, a much more attractive separation involves a gas separation membrane that permeates the larger propane and butane at a more rapid rate compared to methane. Membranes that perform this separation have been studied and include the commercialized rubbery polydimethylsiloxane (PDMS) and its derivatives, highly glassy materials such as poly[1-(trimethylsilyl)-1-propyne] (PTMSP), polymers of intrinsic microporosity (PIMs), and certain polynorbornene derivatives (PNB). Polynorbornenes have generated high interest lately because they can demonstrate higher separation efficiencies compared to rubbery PDMS, though they don't suffer as much from the aging and collapse of free volume that are endemic in PTMSP and PIMs. Polynorbornenes have been regarded as intermediate materials between the rubbery and glassy polymers and may offer advantages compared to either, though they do present challenges that need to be overcome.
Polynorbornenes encompass a large family of polymers with several structural motifs that are often categorized based on the polymerization mechanism. Ring-opening metathesis polymerization (ROMP) is the most widely used and versatile technique to produce polynorbornenes, though these polymers have not exhibited exceptional performance as membranes for heavy hydrocarbon separations. Cationic polymerizations of polynorbornenes are also known, but often produce low molecular weight materials with poor mechanical properties and unknown gas separation characteristics. The most promising polynorbornenes have resulted from addition-type polymerizations that keep intact the bicyclic nature of the polynorbornene backbone, have high chain rigidity and glass transition temperatures, and have demonstrated superior heavy hydrocarbons separations compared to PDMS. The addition-type polynorbornenes face several important challenges: a general lack of diversity in substituent availability off the polynorbornene backbone, relatively low polymerization yields compared to the ROMP polynorbornenes, and a need to further improve hydrocarbon selectivities in natural gas upgrading. The work described in the present disclosure addresses and solves these challenges.
Further embodiments and the full scope of applicability of the present disclosure will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Enhanced yield, structural control, and transport properties of polynorbornenes for natural gas upgrading through Mizoroki-Heck cross-couplings


A thermal overload and resonant motion control circuit is provided for an audio speaker, the circuit generating a feedback signal to control the input applied to the speaker, which feedback signal is dependent on both the drive current to the speaker and the speaker impedance. More specifically, the feedback signal has a voltage which is substantially equally to the absolute value of K(bv−ai)H(s); where,    K=a gain for the circuit,    i=current of drive signal applied to the speaker,    v=voltages of drive signal,    a=percentage of drive current (i) sensed by the control circuit;    b=percentage of drive voltage (v) sensed by the control circuit,    H(s)=a lowpass filter transfer function for a lowpass filter of the control circuit, and    s=a complex frequency variable.

Audio speakers, particularly when being driven at the upper end of their operating range, are subject to failure in at least two ways. First, an excessive drive current applied to the voice coil of the speaker or a high current applied for an excessive time can overheat and burn out the voice coil and/or cause other damage in the speaker. Heating of the voice coil is also a function of the exclosure used for the speaker, ambient temperature, and other factors. Second, speaker cones have a resonant frequency and, for a given drive signal, cone movement will be significantly greater at or near the cone's resonant frequency than for drive signals at other frequencies. Particularly when a speaker is being driven in its upper operating ranges, additional cone movement caused by resonance can overdrive the cone, causing tearing or other damage thereto and/or to components of the speaker attached to or otherwise moving with the cone.
Heretofore, the problem of protecting a woofer or other speaker from overload damage has been dealt with by providing an electrical circuit to monitor current drive to the speaker and generate a feedback control in response thereto and a separate device, generally a low impedance mechanical device such as an accelerometer or secondary sensing coil, to detect cone movement, including movement as a result of resonance, and to generate a separate feedback signal in response to such movement. No mechanism has been provided for directly (or indirectly) measuring/detecting coil temperature and compensating for increases in such temperature. While such overload control/protection circuits for speakers utilizing two separate detection schemes, including the mechanical detection scheme for cone movement, are generally effective for protecting the speakers, this arrangement is relatively complicated and expensive, particularly the mechanical detectors for cone movement, and it would be preferable if a single, all electronic circuit could be provided to detect and provide control/protection for both drive-current-induced thermal overload and excessive cone movement resulting from resonance or other causes. It would also be desirable if such circuit could detect heating of the voice coil and compensate for such heating, regardless of cause.

Thermal overload and resonant motion control for an audio speaker


Provided is a current-voltage conversion amplifier circuit including: a plurality of light receiving devices generating a current signal proportional to an amount of light by receiving the light; multipliers amplifying the current signal, converting the amplified current signal into a first voltage signal, outputting the amplified current signal, or outputting the converted first voltage signal; multi input amplifiers outputting first and second output voltage pairs through a process for receiving output values of multipliers and an offset voltage and amplifying the received output values and offset voltage; a multiplexing unit selecting and outputting one first and second output voltage pair among the first and second output voltage pairs outputted from multi input amplifiers; and a signal conversion unit converting a difference value between first and second output voltages outputted from the multiplexing unit and outputting the converted digital signal.

The present invention disclosed herein relates to an amplifier circuit, and more particularly, to a current-voltage conversion amplifier circuit.
An amplifier circuit means an electronic circuit amplifying the voltage, current, and power of an input signal to generate an output signal. The amplifier circuit includes a voltage amplifier circuit, a current amplifier circuit, a power amplifier circuit, and a current-voltage amplifier circuit converting current signal into voltage signal and amplifying it.
A high-impedance preamplifier and a transimpedance amplifier are mainly used as the current-voltage conversion amplifier circuit. The high-impedance preamplifier improves the reception sensitivity by increasing a load resistance to increase an input voltage. The transimpedance amplifier uses a resistance in a feedback loop. The thermal noise of the transimpedance amplifier is reduced by the resistance. Additionally, the transimpedance amplifier has a more improved dynamic range compared to the high-impedance preamplifier.
However, the transimpedance amplifier requires a resistance of hundreds of ohms to process a small current signal. Therefore, when the transimpedance amplifier is used in the current-voltage conversion amplifier circuit, its power consumption is high and its circuit area is increased.

Current-voltage conversion amplifier circuit including multiplier with a current offset removal unit and multi input amplifier

ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE


A nanostructure having at least one nanotube and at least one chemical moiety non-covalently attached to the at least one nanotube. At least one dendrimer is bonded to the chemical moiety. The chemical moiety may include soluble polymers, soluble oligomers, and combinations thereof. A method of dispersing at least one nanotube is also described. The method includes providing at least one nanotube and at least one chemical moiety to a solvent; debundling the nanotube; and non-covalently attaching a chemical moiety to the nanotube, wherein the non-covalently attached chemical moiety disperses the nanotube. A method of separating at least one semi-conducting carbon nanotube is also described.

The present invention relates to nanotubes attached to a variety of chemical moieties in various solvents. More specifically, the invention relates to carbon single-walled nanotubes (SWNTs) attached to soluble polymers or soluble oligomers in a variety of solvents.
In their pristine state, carbon single-walled nanotubes (SWNTs) exist as randomly bundled tubes with varying chirality, diameter, and properties, such as metallic, semi-metallic, and semi-conducting electronic behaviors.
Although a variety of methods are known for dispersing SWNTs, existing methods suffer from various disadvantages. For example, although debundling nanotubes may increase solubility of SWNTs in common solvents, one disadvantage is that current methods attain only limited solubility. Another disadvantage is that covalent and ionic functionalization of SWNTs can be detrimental to-the SWNTs' unique and desirable properties, specifically, the SWNTs' electronic behavior. Furthermore, some existing methods limit the orientation in which a chemical moiety may attach to a nanotube
Another disadvantage of existing methods of dispersing SWNTs by attachment of a chemical moiety is the limited ability to selectively disperse semi-conducting (sc) SWNTs and, optionally, separate semi-conducting (sc) nanotubes from metallic (met) carbon nanotubes.
Consequently, what is needed is a method that permits a chemical moiety to attach to a carbon nanotube non-covalently. What is also needed is a method for dispersing carbon nanotubes in a range of suitable solvents. What is further needed is a method for dispersing and separating semi-conducting (sc) carbon nanotubes from metallic (met) SWNTs.

Nanotubes and methods of dispersing and separating nanotubes


The invention relates to a device for a coupling an agricultural implement to an agricultural tractor, in which the operation to release the coupling between the agricultural implement and the agricultural tractor can be easily implemented.

1. Field of the Invention
The present invention relates to a device for coupling an agricultural implement to an agricultural tractor.
2. Description of the Related Art
In general, a link is provided at the rear of an agricultural tractor. A device for coupling an agricultural implement (hereinafter referred to as "coupling device") is attached at the rear end of the link. When an agricultural implement is coupled to an agricultural tractor, first, a coupling ball provided in the front portion of the implement is accommodated in a hook portion provided in the coupling device of the agricultural tractor. Next, the coupling ball is locked with a stopper of the coupling device so as not to be escaped from the hook portion of the coupling device. When the coupling is to be released, first, the operator pulls a control lever of the coupling device so as to slide the stopper to the coupling-ball-releasing position, and the stopper is held in that position. Next, the coupling ball is removed from the hook portion of the coupling device to release the coupling.
European Patent No. 0937592 discloses a conventional coupling hook comprising a hook body, a blocking device, a control lever, resilient means and a pivoting lever. The hook body includes a hook-shaped portion housing a coupling ball. The blocking device is housed in a cavity of the main body. The blocking device can slide through a first opening (slit) so as to block and release the coupling ball. The control lever is housed in the cavity of the body. The upper portion of the control lever protrudes from a second opening. The control lever slides the blocking device so as to block and release the coupling ball. The resilient means are for holding the blocking device in the blocking position. The pivoting lever is rotatably coupled to the hook body, the blocking device and the control lever. In addition, the pivoting lever is coupled to the resilient means. The control lever includes a clamping tooth. The clamping tooth is provided in the middle in the vertical direction of the rear part of the control lever. The hook body includes a correspondingly shaped portion to the clamping tooth. The correspondingly shaped portion is provided on the outside of the hook body, in front of the first opening. When the coupling ball is released, the control lever is pulled upward so as to slide the blocking device into the cavity. Next, the control lever is turned backward so that the clamping tooth of the control lever engages with the correspondingly shaped portion provided on the body of the hook. Thus, the control lever is fixed to the body of the hook, and the coupling ball is released.
In addition, Japanese Patent No. 2601409 discloses a coupling hook comprising a hook body, a locking pawl and a closing spring. The hook body includes a bearing recess for accommodating a coupling ball. The locking pawl is provided in the hook body and blocks the coupling ball. The closing spring urges the locking pawl toward the locking position. When the coupling ball is released from the coupling hook, first, an opening lever is pulled so as to bring a supporting face into contact with a round bearing surface. The supporting face is a groove provided in the opening lever. The bearing face is provided in the boundary region of a through-aperture of the hook body. Next, the opening lever pivots around the round bearing surface so as to slide the blocking device to a releasing position where the locking pawl releases the bearing ball. Next, a second fixing stop is brought into contact with an arresting stop. The second fixing stop is provided on the opposite side of the opening lever from the supporting face. The arresting stop is provided on a region at the outside of the hook body across the opening from the bearing face. At the same time, the opening lever is slid toward the bearing recess. Following the supporting face of the opening lever, a first fixing stop is retracted so as to rest on the bearing face. The opening lever is thus fixed to the hook body.
The coupling hook of the above-mentioned European Patent includes a blocking device, a control lever, a lever element and resilient means on top of the hook body. Therefore, there are a large number of parts and the cost can be high. In addition, for the release of the engaged coupling ball, the control lever needs to be pulled, to be turned backward while retaining the pulling state, and to be engaged with the hook body. Thus, the operation from the driver's seat, which is located diagonally in front of the coupling hook, becomes complicated.
In the coupling hook of the above-mentioned Japanese Patent No. 2601409, for release of the coupling ball is released, a plurality of steps are necessary. That is to say, (1) pulling the opening lever upward so as to slide the blocking device to the releasing position where the locking pawl releases the bearing ball, (2) having the opening lever pivot around the bearing surface provided in the through-aperture of the hook body from the state that the opening lever is pulled, and (3) after having the opening lever pivot, sliding the opening lever toward the bearing recess so as to bring the first and second fixing stops of the opening lever into contact with the arresting stop and the bearing face provided in the through-aperture, respectively. Therefore, operation for releasing the coupling is complicated.

Device for coupling implement to agricultural tractor

Abstract: When the coupling of the agricultural tractor and the agricultural implement is released, first, a control lever of a coupling hook is slid upward against the urging force of a spring until a second guide pin reaches the lower end of a slit. Next, the control lever is turned forward around the second guide pin until a bent portion of the upper portion and the lower portion of the control lever comes into contact with a first guide pin. As a result, the rear end of a stopper is retracted into a cavity in the hook main body of the device through a second opening so as to slide to the coupling-ball-releasing position, and a groove of the stopper is hooked to a hooking pin so as to be fixed.


A detail enhancement system uses a detail filter bank including multiple detail filters covering different frequency ranges. An input video signal representing a digital image is processed in the detail filter, wherein detail signals are extracted by the detail filters at different frequency ranges. Shoot suppression blocks and coring blocks are provided for each detail filter to prevent overshoot/undershoot artifacts and small ringing artifacts, respectively. The overall detail signal is amplitude scaled, and added back to the input signal as an enhancement, to generate a detail enhanced output signal.

In digital video systems such as a digital TV system, different incoming video images may have very different characteristics depending on the video format and the original video source. Some images may contain many high frequency components, indicating large amount of fine details or sharp edges. Other images may contain fewer high frequency components, and appear relatively smooth. Some video images in a high definition format may be generated by conversion from a standard definition video source. While other digital video images may be generated from an analog video source. Therefore, different video images may be quite different in terms of their signal frequency range and frequency distribution.
Image detail enhancement has been a continuing research topic. However, providing a good detail enhancement system that is suitable for different types of digital video images mentioned above, remains to be addressed by conventional solutions.


A three-dimensional laser levelling and angle-calibrating instrument includes: a stand; a magnetically-attractive laser level having a horizontal bottom attractable on the stand, a vertical wall perpendicular to the horizontal bottom and a first laser illuminator mounted on the laser level for projecting a horizontal laser ray for levelling purpose; and a magnetically-attractive laser angle calibrator having a second laser illuminator and attracted on the vertical wall of the laser level for projecting a vertical laser light line for checking a verticality.

For levelling a horizontal plane in engineering construction, a level may be provided for calibrating such a horizontal level. For checking the verticality of a building site, a plumb may be provided for this purpose. It will be costly and inconvenient to purchase and prepare the horizontal level and the vertical plumb separately.
In the circumstances where the levelling and verticality as well as angle calibration must be done simultaneously, such as found in an interior uphostery engineering, to prepare and use the conventional level and plumb separately may defer the engineering work and decrease the job efficiency.
Therefore, the present inventor has invented the device having laser level and angle calibrator combinable on an integrated instrument.

Three-dimensional laser levelling and angle-calibrating instrument with multiple functions


Systems and media for awarding credits based on provided usage information are disclosed. More particularly, hardware and/or software for collecting and disseminating usage information related to electronic documents and for awarding usage credits to users in exchange for providing usage information are disclosed. Embodiments include receiving an indication of the usage of an electronic document by a user and aggregating the received usage indication for the document with usage indications relating to other users. Embodiments may also include creating document utilization information for the electronic document based on the aggregated usage indications and awarding usage credit to the user based on the user's providing statistics on the usage of the electronic document. Further embodiments may include transmitting an indication of the awarded usage credit to the user and receiving a request to use the usage credits.

Personal computer systems are well known in the art. They have attained widespread use for providing computer power to many segments of today's modern society. Personal computers (PCs) may be defined as a desktop, floor standing, or portable microcomputer that includes a system unit having a central processing unit (CPU) and associated volatile and non-volatile memory, including random access memory (RAM) and basic input/output system read only memory (BIOS ROM), a system monitor, a keyboard, one or more flexible diskette drives, a CD-ROM drive, a fixed disk, storage drive (also known as a "hard drive"), a pointing device such as a mouse, and an optional network interface adapter. Examples of such personal computer systems are International Business Machine Corp.'s (IBM's) ThinkCentre™, ThinkPad™, Aptiva™, and IntelliStation™ series of personal computers. The use of mobile computing devices, such as notebook PCs, personal digital, assistants (PDAs), tablet PCs, sophisticated wireless phones, etc., has also become widespread. Mobile computing devices typically exchange some functionality or performance when compared to traditional PCs in exchange for smaller size, portable power, and mobility.
The widespread use of PCs and mobile computing devices in various segments of society has resulted in a reliance on computer systems both at work and at home, such as for telecommuting, news, stock market information and tradings banking, shopping, shipping, communication in the form of hypertext transfer protocol (http) and e-mail, as well as other services. Many of these functions take advantage of the communication abilities offered by the Internet. Such connectivity has facilitated unprecedented amounts of collaboration and sharing of information between individuals, both within organizations and outside organizational structures. This collaboration has resulted in individuals having access to and sharing vast amounts of information, often in the form of electronic documents. Electronic documents are digitized documents that contain text, graphics, photographs, etc., and can be read by various computer systems. Electronic documents may be in any file format, such as Portable Network Graphics (PNG), Joint Photographic Experts Group (JPEG), Graphics Interchange Format (GIF), Tag Image File Format (TIFF), Microsoft Word (DOC), Hypertext Markup Language (HTML), Adobe Systems Inc.'s Portable Document Format (PDF), etc. For many applications, electronic documents, particularly PDF documents, have supplanted printed material for the dissemination of information, as many journals, newsletters, books, articles, etc., are now distributed either exclusively or non-exclusively in electronic form.
While electronic documents possess improved qualities in many ways over hardcopies, such as cost, easy of distribution, and time to prepare, disadvantages of electronic documents when compared to paper documents do exist. One deficiency of electronic documents is that it is often difficult to find the most interesting or useful part of an electronic book or other document. With a paper book, individuals may observe which pages are the most worn or the pages to which the hook naturally opens due to frequent reading of those pages. One can easily discern which book in, say, a library is the most useful based on its wear, and one can also often find the most useful part of the book by noting the wear caused by frequent reading. Because of the fixed nature of an electronic document, electronic documents fail to provide such indications of frequently-read or particularly useful sections of the document.
The vast, amount of content, including electronic documents, available on public networks such as the Internet often makes it difficult for users to find useful and relevant information. Accordingly, many people utilize search engines to assist them in their search. Search engines are programs that search documents on a network for specified keywords and return to the requester a list, of documents where the keywords were found. Typically, a search engine works by sending out a "spider" to fetch as many documents as possible, after which an "indexer" reads the documents and creates an index for the words contained in each document. Each search engine then typically creates indices using a proprietary algorithm so that meaningful results are returned for each query. Example publicly-available search engines include those provided by Microsoft Corporation, Google Inc., Yahoo! Inc., etc.
While search engines are quite powerful, they suffer from some flaws. First, search engines do not always identify the most relevant links early in the search results, forcing the user to spend time reviewing multiple results to find the information they are seeking. Additionally, search engines do not always identify the portion of a document most likely to satisfy the customer or requester, as they only identify, at best, the portion of the document in which the search words were found. This problem is exacerbated for larger documents, as a user may not know where to look in a very long document for the most relevant information. Additionally, search engines are often misled by the frequent appearance of keywords, such as when document developers attempt to mislead a search engine into giving a higher priority for a particular site or document by incorporating large numbers of keywords in the document in a process known as "keyword spamming". Keyword spamming often results in erroneous or misleading query results, making the search engine less desirable for the user. Improving the performance of search engines will likely increase the usage of that search engine and thus the revenue generated from it.
There is, therefore, a need for an effective system to improve the functionality of search engines, particularly when search engines are used to find information contained in portions of electronic documents. In particular, there is a need to find information relevant to a user contained in portions of electronic documents.

This patent is subject to a terminal disclaimer.


The present invention provides a fingerstall-cannulated guide device for accurate and efficient guide wire placement for antegrade femoral nailing systems. The said device comprises a fingerstall with a cannulated guide connected with or without a threaded guide wire. Using this device, surgeons can determine the entry point for the guide wire fast and accurately by tactile hand-eye coordination. After correct entry point is obtained, the guide wire is advanced and the fingerstall-cannulated guide can be easily detached. The device and method can accomplish the following: (1) reduction of the surgery time; (2) reduction of the radiation exposure times, and (3) reduction of the soft tissue damage during surgery. The device is also beneficial for use in fastening together any or all portions of bone surrounding a fracture site.

Find the entry point for the guide wire is one of the most crucial steps in antegrade intramedullary femoral nail placements. Guide wire positioning is usually done by trial and error method under C-arm image guidance. This method takes more time and does not give assurance of correct position of the entry point or trajection of the guide wire. It is always challenging to perform this guide wire positioning in minimum time with maximum accuracy.
Minimally invasive fracture fixation can be technically demanding, especially in body regions characterized by complex bony anatomy and the presence of a significant amount of soft tissue. Hence, this procedure is associated with a high risk of implant malposition. As a consequence, radiation exposure to the patient and the surgeon increases during surgery. Proximal femoral fractures are the second most common fracture in older patients and place a heavy demand on orthopedic departments worldwide. A short surgery time and use of less invasive approaches are the two key-parameters to reduce surgery related morbidity. In addition, an intramedullary nailing of proximal femoral fractures is often accompanied by increased radiation exposure time to control the implant placement [Chong K W, et al. Injury 2006; 37(8):755-762.]. The surgery should be least disruptive to the soft tissue envelope thus preserving blood supply and consequently better bone healing in poor quality osteoporotic bone. An added bonus will be to reduce the radiation exposure to the surgeon who is performing such operations on a regular basis.
A wide range of instruments could be subsumed from simple guiding drill sleeves to targeting tools adapted to the implant design [Krettek C, et al. Clinical Orthopedics and Related Research 1999; (364):267-275]. All of these devices are used to adjust an intended track and to hold a specific position of the guide wire until the implant is inserted. Such devices commonly require the surgeon to extrapolate the inner bony implant path using fluoroscopy in multiple planes that inevitably results in repetitive adjustment steps and drill trials. Hence, there is a need for simple and handy tools that allow a fast and accurate position of the guide wire entry point before intramedullary nail implantation.
The present invention provides the benefits on the reduction of radiation exposure, a decrease of procedure time, as well as a significant reduction of soft tissue envelope damage by a fast and accurate placement of guide wire through entry point.

Fingerstall-cannulated guide for fast and accurate guide wire positioning


A system and technique called magnetoresonant induction of an intrastromal implant that is adapted for corneal re-shaping. The technique is utilized to correct mild to high hyperopia and presbyopia by steepening the anterior corneal curvature in a single treatment, or in periodic treatments over the lifetime of the patient. The system comprises a combination of components including (i) at least one implantable magnetoresonant intrastromal segment, and (ii) an oscillating magnetic field generator together with a dosimetry control system including at least one emitter body adapted for positioning proximate to the patient's eye and intrastromal implant. The system can deliver thermal effects to appropriate stromal lamellae by non-contact inductive heating of the implant which in turn contracts or compresses stromal collagen fibrils into a circumferential cinch about an anterior layer of the cornea and steepens the anterior corneal curvature. A dosimetry control system controls the power level and duration of exposure of the oscillating magnetic field(s) and may be combined with intraoperative corneal topography.

1. Field of the Invention
The present invention relates to devices and techniques for non-contact thermal treatment of a patient's cornea for altering anterior corneal curvature to correct refractive disorders, and more particularly, to implantable intrastromal segments that may be elevated in temperature by magnetic induction to cause lesions in, or shrinkage of, the Bowman's layer and/or stromal lamellae to increase corneal steepness in hyperopic or presbyopic refractive treatments.
2. Description of the Related Art
Refractive disorders of the eye result from the inability of the eye's optic system, consisting of the dome-shaped cornea and the crystalline lens just behind it, to properly focus images on the retina, the nerve layer at the back of the eye. Approximately 80 percent of the refracting power of a human eye is within the cornea. When the cornea is mis-shaped, or the eye is too long or too short along its optical axis, or when the lens of the eye does not function normally, a refractive error occurs. Refractive errors generally include hyperopia, myopia, presbyopia and astigmatisms. Hyperopia is a refractive error that causes poor close-up vision, and is caused by a flattened cornea or by a shortened eye that focuses images beyond the retina (see FIG. 1A). Myopia is the opposite and causes poor distance vision, and is characterized by an elongate eye or steepened corneal shape. This condition causes distant images to focus in front of the retina rather than directly on it (see FIG. 1B). Presbyopia results from aging and is a form of farsightedness caused by diminished ability of the lens to elastically change to refract light. Astigmatism is a condition which causes blurred vision for both near and far objects. In an astigmatic patient, the cornea may be shaped like the back of a spoon rather than having a spherical shape. Such an asymmetric corneal shape creates different retinal focal points. Hence, instead of images focusing on the retina, the images focus on a number of points around the retina resulting in a blurred image.
The optimal shape for a cornea is that of a perfect sphere assuming that axis of the eye is normal relative to the other eye. Glasses and contact lenses correct refractive errors by refracting (bending) light before it reaches the cornea and is transmitted through the lens, in other words, changing the angle at which light enters the cornea.
Several types of surgical procedures have been developed to correct refractive disorders such as myopia, hyperopia and astigmatisms by changing the shape of the cornea. For example, laser procedures can reshape the patient's cornea to some extent to a corrected more spherical shape, the most common procedures being laser in-situ keratomileusis (LASIK) and laser photorefractive keratectomy (PRK). LASIK and PRK correct vision by recontouring the anterior layers of the cornea by means of surface ablation with a laser.
It is useful to provide a description of the anatomy of the patient's eye. FIG. 1C depicts patient's eye 5 which comprises a system of cornea 6 and lens 3 which focuses light on the retina indicated at 4 which is at the back of the substantially spherical body defined by sclera 7. The anterior chamber 8 (and aqueous 9a therein) is separated from the vitreous body 9b by lens 3. Thus, cornea 6 forms the anterior wall of chamber 8 and also acts as a lens element. The cornea 6 is a smoothly curved transparent structure which has a smaller radius of curvature than the opaque sclera 7 and bulges from the smooth outer spherical surface of the eye. Refractive errors occur when the cornea and lens do not focus incoming light on retina 4.
The cornea 6 is uniquely structured to transmit light into the eye. The primary structure of the cornea is the stroma, which comprises approximately 90 per cent of the cornea's thickness. The stroma is comprised of lamellae which lie in flat sheets and extend from limbus to limbus. Each lamella (ayer or sheet) consists of strong, parallel collagen fibrils which are maintained in a regularly spaced hexagonal separation by a ground substance or GAGs (for glycoaminoglucans, also called a glycoprotein and mucopolysaccharide matrix). Between the lamellae are keratocytes layers (the fibroblasts), the constitutive cells of the cornea which produce the GAGs and support synthesis of collagen. It is well known that the elongate stromal collagen fibrils may be longitudinally contracted by application of heat to temperatures above about 60.degree. to 65.degree. C. See, e.g., U.S. Pat. No. 4,461,294 issued to Baron; U.S. Pat. No. 4,976,709 issued to Sand; U.S. Pat. Nos. 4,326,529 and 4,381,007 issued to Doss; and U.S. Pat. No. 5,533,999 issued to Hood.

Non-contact magnetoresonant implant system and techniques for periodic corneal re-shaping


A drive device with electronic circuit, including floated wiring for electrically connecting the solid wirings of a circuit to each other and an electronic circuit mechanically connected to an engine, wherein the electronic circuit is formed so that the flat surface thereof including the floated wiring is substantially disposed vertically relative to the output axis of the engine, whereby the vibration of the engine in the major X- and Z-directions can be prevented from applying to the floated wiring in Y-axis direction to increase the seismic resistance of the electronic circuit, and the arrangement of the drive device having the electronic circuit mechanically installed thereon can be realized.

1. Field of the Invention
The invention relates to a vehicular drive apparatus and, more particularly, to a technology for providing the drive apparatus with an integrated electronic circuit for controlling the drive apparatus.
2. Description of Related Art
A drive apparatus installed in a vehicle needs an electronic control unit for controlling a fuel supply system for the engine and a speed shift mechanism of the automatic transmission if the drive apparatus is a combination of a combustion engine (referred to as "engine" in this specification) and an automatic transmission. In the case of a hybrid drive apparatus that incorporates an engine and an electric motor (a motor or a motor-generator) as drive power sources, and that employs a transfer apparatus combined with the drive power sources, the drive apparatus needs a power unit and an electronic control unit for controlling a fuel supply system for the engine and a power line for the electric motor.
Conventionally, it is normal to dispose an electronic control unit and a power unit as mentioned above at locations in a compartment of a vehicle which have good thermal and vibrational conditions because these circuits incorporate chips that are susceptible to heat and vibrations.
In normal cases, since the electronic circuits of the electronic control unit and the power unit are not disposed at locations exposed to sever vibrations as mentioned above, there is no need to consider such vibrational conditions in disposing and arranging the electronic circuits. However, modules are now being used for the purpose of size and cost reduction. Along with this trend, it is conceived to mount an electronic circuit in an engine room, directly on an engine or indirectly from the engine via an accessory or the like. In this case, the electronic circuit is placed under a harsh condition where the circuit directly receives vibrations from the engine. Therefore, there are many problems related to resistances against such conditions. With regard to the thermal resistances of circuit materials of a module and chips embedded therein, some improvements have been made based on contrivances in cooling means. However, improvement in vibration resistance of a module as a whole is difficult. Thus, this technical idea has not been developed to a level of practical use.


Method for maintaining active control of an autonomous vehicle can involve confirming the active presence of a human in a semi-autonomous vehicle. The human's active physical control and monitoring of the semi-autonomous vehicle can be verified by detecting that a throttle pedal on the semi-autonomous vehicle is depressed relative to a non-actuated position. The vehicle can then continue semi-autonomously as long as the active physical control and monitoring by the human is confirmed. Once the throttle pedal is found to no longer be depressed, the vehicle can be returned to normal human control.

Field
The application relates to systems and methods for use with autonomous vehicles, particularly to maintain active physical control and monitoring of an autonomous vehicle by a human driver.
Description of the Related Art
Numerous parties have raised safety concerns with respect to autonomous, self-driving vehicles. Traditionally, vehicles are driven by human drivers, and that arrangement has an established safety record. Although autonomous vehicles might currently or in the future be safer than a human-driven vehicle, it may still be beneficial to ensure that a human driver is present and ready to take control if the autonomous vehicle appears to be driving in a dangerous manner. Further, regulations in certain jurisdictions may require the presence of a human driver, and some way to ensure that the human driver remains in active physical control of the vehicle, and actively monitors the vehicle. Thus, systems and methods that facilitate or require participation by a human driver can potentially improve operation and safety of the vehicle, and comply with regulatory requirements for the use of vehicles that may otherwise be capable of driving without a human driver. Further, it can be desirable to make this interaction between the human driver and the vehicle less burdensome.
Vehicles described herein may have certain autonomous-driving capabilities. However, to the extent that the active physical control and monitoring of a human driver is required, they would not be fully autonomous. Thus, such vehicles will be referred to herein as "semi-autonomous" vehicles.