Abstract: Disclosed is a method and apparatus for processing two analog composite video signals to be displayed to a human observer. The system includes at least a first and a second video source for generating first and second analog composite video signals respectively, and a selector coupled to the first and second video sources. The selector is operative to supply either the first or second analog composite video signal to one input of a video processor and independently and simultaneously supply either the first or second analog composite video signal to a second input of the video processor. The video processor is operative under control of a CPU to generate an output analog composite video signal comprised of a portion of the analog composite video signal supplied to the video processor's first input and a portion of the analog composite video signal supplied to the video processor's second input.

Abstract: A video display, which may be a television receiver with associated set top device, an intelligent television receiver, or a personal computer system enabled for television display, has associated therewith a remote control of the three axis type which controls modification of the visual images displayed.

Abstract: Disclosed are apparatus and method for measuring a characteristic of a film comprised of a material that is a superconductor below a critical temperature. The apparatus includes a magnetic circuit for inducing an alternating magnetic flux at a localized region of a surface of the film. The circuit includes a magnetic core (42) having a gap (44) made therein and a drive winding (46) coupled thereto. A current source (50) is coupled to the drive winding for passing an alternating current therethrough for inducing an alternating magnetic flux within the gap. Measurement circuitry (54, 56) is responsive to a current induced within the film by an entry of the magnetic flux into the film. A processor (60) is coupled to the measurement circuitry and determines a critical current density of the superconducting film within the localized region.

Abstract: A superconductive transmission line is formed of mixed metallic oxide ceramic material, particularly Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x drawn epitaxially upon a substrate. The superconductive material has basal crystallographic planes in alignment with copper oxide of the ceramic material. The planes are parallel to the substrate. The transmission line is constructed of a plurality of electrically conductive elements, each of which is formed of the superconductive material. The conductive elements are arranged with the crystalline planes parallel to an axis of the transmission line, along which axis power is to flow. Thereby, magnetic fields induced by currents flowing in the conductive elements intersect the conductive elements perpendicularly to the basal crystallographic planes to maximize the current which can flow while retaining linearity between magnetization and applied magnetic field.

Abstract: An improved signature verification method using dynamic signature characteristics in the frequency domain. Analysis of a signature in the frequency domain is employed when time domain analysis does not adequately distinguish between true signatures and forgeries. The preferred signature characteristics that are measured are two acceleration components of the pen, and the rate of change of axial pressure on the pen. More specifically, correlation functions operating on a sample and reference signature produce a correlation score. If the total correlation score is in a selected interval, then the above measured characteristics are analyzed in the frequency domain with the magnitude squared coherence function.

Abstract: A linear disk actuator is disclosed incorporating a magnetic circuit for reducing stray magnetic fields in the region of the disks and recording heads of a magnetic recording disk system. The moving part of the actuator is provided with a plurality of coils mounted thereon, at least two of which are energized simultaneously and in magnetically opposing relationship to reduce the amplitude of the stray magnetic fields. Movement of the actuator is achieved by both energized coils interacting with a set of alternating poles positioned on the stationary part of the actuator.

Abstract: A signature verification system includes means for obtaining acceleration data and pressure data related to a given signature and means for comparing that data with reference data previously obtained from an identified signer. The correlations between segments of a reference pressure signal and a sample pressure signal are computed. This process involves successively measuring the correlation as the two segments are shifted with respect to each other. The amount of the shifts that produce the maximum correlations between the pressure signal segments is stored in memory, and these shift values are utilized to determine the correlations of respective pairs of segments of the acceleration data. Since the acceleration data is not independently shifted in computing the correlations, substantial processing time is saved. In addition, the overall performance of the signature verification system is improved both in terms of processing time and in error rate as compared to the prior system.

Abstract: A signature verification system includes means for obtaining acceleration data and pressure data related to a given signature and means for comparing that data with reference data previously obtained from an identified signer. The correlations between segments of a reference pressure signal and a sample pressure signal are computed. This process involves successively measuring the correlation as the two segments are shifted with respect to each other. The amount of the shifts that produce the maximum correlations between the pressure signal segments is stored in memory. The corresponding segments of acceleration data are shifted with respect to one another by an amount which is .+-.1 time units of the stored shift values during subsequent correlations of the acceleration data.

Abstract: A signature verification method is based on a comparison of the dynamics of a reference and a sample signature. Acceleration and pressure signals produced by a known person when writing his or her signature are stored and used as a reference signals. Then, at a later time, a person whose signature is to be verified writes his or her signature to produce acceleration and pressure signals that are compared to the reference signals. The process of comparison involves segmenting the two sets of signals to facilitate identifying regions of high probable correlation and then correlating corresponding segment pairs. Segmentation is based on pen lifts which represent reproducible timing marks in the signatures. According to the disclosed method, a pen or other writing instrument is used which produces a signal representative of the first time derivative of the pressure forces exerted on the stylus of the pen. The second time derivative of the pressure forces is computed from the measured signal.

Abstract: A writing implement having special applicability for use as a pressure and acceleration sensitive element for use in a Signature Verification System. The pen structure includes both a writing implement for making a visible record and also includes unique transducer structures for providing both acceleration and pressure data to a remotely located verification system. The pressure sensing element is axially mounted within the pen and produces pressure signals due to axial pressure on the pen tip as an individual writes. The accelerometer structure comprises a hollow tubular piezoelectric member supported at one end and having four circumferentially disposed electrodes on the outer surface thereof, which are appropriately interconnected to produce two orthogonal acceleration component signals A.sub.x and A.sub.y.

Abstract: A linear motor adapted for driving a magnetic recording head reciprocably across the surface of a magnetic recording disk in a disk file has its stator located between the disks. The stator includes parallel magnetic yokes composed of plates extending parallel to the disks. At least one of the plates carries an array of regularly spaced and alternating magnetic pole elements, rigidly secured to one yoke with a gap extending between the yokes including the alternating poles providing a space within which the armature reciprocates, from one magnetic polarity to the opposite a plurality of times per reciprocation of the armature. End poles are provided at each end of the array, which are matched to collect the return flux from the adjacent distal pole to reduce fringing flux which emanates towards the disks and the recording heads.

Abstract: A magnetoacoustic system adapted to use as a keyboard can employ a serpentine acoustic delay line passing under a number of transducers which are activated simultaneously with a current pulse through the wire. Magnets adjacent to the wire generate magnetoacoustic pulses along the wire which arrive sequentially at a sensor at one end of the line. For each key on a keyboard at least two magnets are associated with each key position with one magnet affixed in position and one reciprocably movable towards and away from the wire in a response to actuation of the key. The magnet which remains close to the wire is used to provide a "location" signal indicating the location along the delay line provided by the wire by producing an acoustic pulse for that point on the wire for each clock pulse of current which passes through the wire.

Abstract: Using a sonic delay line approach, the distance of a point from the ends of a wire is measured by the time required for an acoustic pulse to move along a wire. A magnetostrictive wire extends between its endpoints with several magnetic pickup coils connected in series located at each end of the wire which are adapted to pick up an encoded train of magnetoacoustic signals. A position signalling electromagnetic drive head can be moved along the coil to any desired position. The head can be pulsed electrically to produce an appropriate sequence of acoustic pulses in the magnetostrictive wire. When those pulses are received by an appropriate sequence of coils connected in series which are properly connected (plus and minus), a large pulse is produced at one time position of the waves as they pass through the sequence of coils. Otherwise, a small signal is produced while the pulses pass by.