Abstract: A nonvolatile magnetic memory device having a nonvolatile magnetic memory array comprising write-in word line(s), bit lines and tunnel magnetoresistance devices, wherein when data is written into the tunnel magnetoresistance device, a current I(m)RWL is passed through the m-th-place write-in word line, a current g(0)·I(n)BL is passed through the n-th-place bit line, and at the same time, a current g(k)·I(n)BL is passed through the q-th-place bit line (q=n+k, k is ±1, ±2, . . . , and the total number of the lines is K), and a spatial FIR filter assuming magnetic fields, which are supposed to be formed in the n-th-place bit line and the bit lines that are K in number by the current I(n)BL, to be discrete pulse response and assuming the coefficients g(0) and g(k) to be tap-gains is constituted of the n-th-place bit line and the bit lines that are K in number.

Abstract: In a concept search, the user cannot easily create an effective seed document own his/her own. Further, the concept search trainer automatically changes the weights assigned to characteristic terms; however, such changes may not always increase the retrieval accuracy. The document retrieval method of the present invention uses thesaurus data to support the user's seed document creation in a first search cycle and presents newly extracted characteristic terms to the user in second and subsequent search cycles. The retrieval accuracy increases because the present invention provides a user interface that permits seed document adjustment.

Abstract: A braking member having a friction surface includes a matrix and a nickel-tungsten alloy layer disposed between the matrix and the friction surface. The nickel-tungsten alloy layer may form the friction surface. The braking member may include an additional nickel or copper layer, and such a layer may be disposed between the nickel-tungsten alloy layer and the matrix. A further metal layer may be disposed between the nickel-tungsten alloy layer and the friction surface, and the further metal layer may form the friction surface.

Abstract: Where data are recorded onto a phase-change disk according to the MCAV (modified constant angular velocity) scheme to enable high-density recording and high-speed random access, marks and spaces are formed by using recording pulses having a front end pulse and a rear end pulse that are delayed so as to be suited to each of a low linear velocity zone and a high linear velocity zone. This is done by changing the pulse widths of the front end pulse and the rear end pulse by varying the positions of the rising edge and the falling edge of the front end pulse and the rear end pulse, respectively, that constitute the recording pulses. Thus, recording compensation suitable for each linear velocity is effected.

Abstract: A digital signal reproducing apparatus comprising a magnetic head for reading a video signal from a magnetic tape, a rotary transformer, a reproduction amplifier, a reproduction equalizer, a phase-locked loop, a threshold discriminator, and an amplitude detector. The amplitude detector detects a dropout by threshold-discriminating the nonequalized reproduced signal, and the frequency characteristic of the equalizer is changed in response to detection of any dropout so as to compensate for the dropout. The threshold discriminator detects the reproduced digital signal from the equalized reproduced signal in accordance with a clock signal extracted by the phase-locked loop. The apparatus is capable of reproducing an errorless video signal by compensating for any dropout on the magnetic tape.

Abstract: It is intended to converge parameters stably in a short time upon automatic adjustment of parameters of a bit identifier by which a signal reproduced from a magnetic recording medium and equalized by the Nyquist standard is compared with a threshold value and converted into a binary signal. An estimation value H(j) of an equalization error is cleared in step 1. Such estimation values H(j) are added in step 2 without being limited in the number of occurrences of addition. A result of the addition is compared with a converging coefficient M in step 3. As long as the result of the addition does not exceed the converging coefficient M, addition is repeated. When the result of the addition reaches the predetermined value, a fixed step .DELTA. is added to or subtracted from a parameter in response to the estimation value H(j). Therefore, parameter renewal interval is variable in response to the amount of equalization errors.

Abstract: A reproduction equalizer including a linear equalizer for linearly equalizing a source signal read from a recording medium, a nonlinear cancellation means for cancelling intersymbol-interference (ISI) contained in the reproduction signal, a decoder for decoding the ISI free signal to reproduce a digital signal prior to storing into the recording medium and means for automatically calculating and/or updating the ISI data held in the nonlinear cancellation means on the basis for the equalized source signal for each address defined by the reproduced digital signal. The nonlinear cancellation means includes a lookup table storing the ISI data, a circuit for generating an address for reading out the ISI data from the lookup table, and a circuit for subtracting the ISI data read out from the lookup table from the equalized source signal. At an initial stage, the calculation means calculates the ISI data, and in a normal operation mode, the calculated ISI data is used.

Abstract: A bit detecting process for identifying binary bit values of digitized signals whose bit amplitudes may be distorted. A digital signal which represents the amplitude of a bit at discrete clock intervals is generated and the difference between a threshold value and the value of the digital signal is determined. A first integral method algorithm or a second second-order difference method algorithm, each of which identifies the binary value of the bit, is selected as a function of the determined difference.

Abstract: Burring by way of a grind stone using a robot has been rarely practiced because the correction of abrasion of the grind stone involves a problem. There has been hitherto proposed a method for correction of abrasion by making use of a force sensor or a special tool holder apparatus. However, since the apparatus is expensive and low in reliability, it has not been practical. In the present invention, a coordinate system is set to a wearing tool mounted to a wrist of a robot separately from the rectangular coordinates of the robot, and the worn amount of the tool detected by use of a sensor is subjected to parallel shifting on the coordinate system of the tool set to the tool to effect correction of abrasion, which is characterized in that a special hard is not required, and operation is simple.