Abstract: An apparatus is used for determining at least one parameter relating to an elongate member disposed within a vessel. The apparatus includes at least one measurement unit having a light emitting component and a corresponding light receiving component. The light receiving component is positioned apart from the light emitting component such that the elongate member is positionable between the light emitting component and the light receiving component. Additionally, the light emitting component is adapted to emit light towards the light receiving component, and the light receiving component is adapted to generate a signal corresponding to the light received from the light emitting component. A method for determining at least one parameter relating to the elongate member disposed within the vessel is also provided.

Abstract: An electronic learning device for receiving a book having a plurality of successive page spreads, at least one page spread having selectable content and an optically readable page identifier. The device includes a housing configured to receive the book, a position sensor in the housing configured to determine the location of the selectable content on the at least one page spread, an optical sensor in the housing configured to irradiate and detect the page identifier on the at least one page spread and control electronics in the housing operatively coupled to the optical sensor and to the position sensor and configured to synchronize sequential operation of the position sensor and the optical sensor.

Abstract: A computer peripheral toy device is provided that connects to a personal computer and enables a child user to create drawings, animated figures, cards, posters, and other projects and items. The device includes a housing having a drawing tablet and a stylus that connects to the housing for use on the drawing tablet. There a plurality of buttons on the top surface of the housing that a user depresses when engaging in a drawing activity. Computer software is provided for installation on the personal computer in order to display data associated with a drawing activity. When executed by the computer, the computer software causes the computer to respond to the messages received from the controller to engage in a drawing activity using drawing style parameters based on which of the drawing style buttons, color palette buttons and design tool buttons are selected by a user.

Abstract: A thermal time date stamp including a printing apparatus, system and method for recording the date and time on a flat paper sheet includes a paper guide for transporting the paper beneath a thermal print head and thermal transfer ribbon, a display for confirming the time and date that is synchronized to the print, and a microprocessor for inputting a graphic image of the time and date displayed to the print head.

Abstract: An electronic learning device for receiving a book having a plurality of successive page spreads, at least one page spread having selectable content and an optically readable page identifier. The device includes a housing configured to receive the book, a position sensor in the housing configured to determine the location of the selectable content on the at least one page spread, an optical sensor in the housing configured to irradiate and detect the page identifier on the at least one page spread and control electronics in the housing operatively coupled to the optical sensor and to the position sensor and configured to synchronize operation of the position sensor and the optical sensor.

Abstract: An electronic learning/teaching device operates with and without a printed sheet element having an arrangement of selectable content by means of a user responsive sensor array beneath a surface configured to receive the element. The sensor array is formed by cross-points of two sets of crossing conductive lines, one set being driven sequentially with a radio frequency square wave and the other set being sampled sequentially though a high impedance amplifier connection with an asynchronous detection circuit. Where more than one cross-point location is user activated, algorithms are used to identify one cross-point sensor location as the user activated selection.

Abstract: An electronic interactive system including an electronic device and a book for use with the electronic device. The electronic device includes an optical page identification system capable of autonomously identifying page identifier codes uniquely associated with each of a plurality of page spreads of the book.

Abstract: An electronic learning/teaching device operates with and without a printed sheet element having an arrangement of selectable content by means of a user responsive sensor array beneath a surface configured to receive the element. The sensor array is formed by cross-points of two sets of crossing conductive lines, one set being driven sequentially with a radio frequency square wave and the other set being sampled sequentially though a high impedance amplifier connection with an asynchronous detection circuit. Where more than one cross-point location is user activated, algorithms are used to identify one cross-point sensor location as the user activated selection.

Abstract: There is disclosed a web of record members of the composite label web, tag and linerless types with cracks or fissures through the webs so that the position of the web can be detected by an optical detector. Apparatus can be used to convert the web into more usable form which includes for provision of optically detectable cracks or fissures in the web. These cracks are made by crushing the web locally between one or more crushing cutters and a back-up roll which cooperates with zero clearance. The method and apparatus can produce a reliably detectable web at low cost. The optical detector includes a source of light and a bicell detector between which the web with the cracks or fissures passes. The bicell detector produces a first output signal representing the amount of light impinging on a first portion of the detector and a second output signal representing the amount of light impinging on a second portion of the detector.

Abstract: An electronic article surveillance system responsive to the distance to a target within an interrogation zone is provided. The interrogation zone is defined by an electromagnetic field generated with a known level and transmitted by at least one antenna. A target within the interrogation zone can be any object, such as a person or shopping cart, within the interrogation zone. The target may include an EAS marker securable to an article for passage through the interrogation zone. The EAS marker is detectable at a frequency when in the electromagnetic field, and is detected by EAS detection equipment, as known in the art. The target within the interrogation zone is detected, and the distance from the antenna to the target is measured. The level of the electromagnetic field is controlled according to the distance to the target within the interrogation zone. The output level is adjusted to according to the distance to the target.

Abstract: There is disclosed a web of record members of the composite label web, tag and linerless types with cracks or fissures through the webs so that the position of the web can be detected by an optical detector. Apparatus can be used to convert the web into more usable form which includes for provision of optically detectable cracks or fissures in the web. These cracks are made by crushing the web locally between one or more crushing cutters and a back-up roll which cooperates with zero clearance. The method and apparatus can produce a reliably detectable web at low cost. The optical detector includes a source of light and a bicell detector between which the web with the cracks or fissures passes. The bicell detector produces a first output signal representing the amount of light impinging on a first portion of the detector and a second output signal representing the amount of light impinging on a second portion of the detector.

Abstract: A method and apparatus for hybrid analog-digital pulse compression, as well as, a method of use and manufacture includes an analog intermediate frequency filter, a converter, and a digital correlator. The analog intermediate frequency filter filters and weights returned echo signals, and the digital correlator compresses the filtered and weighted echo signals. The frequency or impulse response of the digital correlator is set based on the frequency or impulse response of the analog intermediate frequency filter to obtain a pulse compressor with minimal mismatch loss and improved sidelobe suppression. The invention provides for the lowest possible sampling rate of analog-to-digital convertors used with the apparatus; thus, minimizing the cost of this device and all subsequent digital processing.

Abstract: Sea clutter can be removed from radar signals by accurately determining sea velocity in a coverage area of a radar scan, updating a median value for the coverage area, and selecting a clutter rejection filter for the coverage area biased on the median value for the coverage area. Preferably, a median sea velocity is stored for each coverage area, as the median value. When processing begins for a coverage area, a previously stored median sea velocity is retrieved and updated. The median sea velocity is updated by converting the median sea velocity into a median phase difference between two echo signals, based upon carrier frequency and the time between receipt of two echo signals, which is preferably more than one interpulse period. The difference in phase between the two echo signals is compared with the median phase difference and the median sea velocity is increased if the median phase difference is smaller and decreased if the median phase difference is larger.

Abstract: A method and apparatus are disclosed for providing optimum radar beam patterns to provide complete radar coverage at both short ranges and long ranges in a radar system using solid state transmitters. Long pulses for covering long ranges are generated and split into a pair of signals with a specific amplitude and phase relationship. These signals are provided to a transmit beam forming matrix of an array antenna to generate an optimum pattern for long range coverage. Short pulses are generated for providing short range coverage and are split into a pair of signals which are phase shifted differently from the long pulses. These signals are then provided to the transmit beam forming matrix to generate a different beam pattern for providing short range detection. The short range beam pattern has a sufficient amount of energy to provide coverage to maximum desired altitude over a range extending to where echoes from the long pulses may be received undistorted.

Abstract: A unitary surface acoustic wave device for continuous quadraphase coding of a high amplitude video impulse with provisions for controlling the rise and fall times of such impulse.

Abstract: A phase detector receives two input digital signals representing Cartesian coordinates of a vector and outputs a digital signal indicative of the phase angle of the vector. The input digital signals are logarithms of the square of, for example, in-phase and quadrature components of a radar signal and are subtracted in the phase detector to produce a difference signal having a magnitude and a polarity. The polarities of the difference signal and the two information signals are used to determine the octant of the phase angle by addressing a read only memory. The magnitude of the difference signal is used as an address of a read only memory storing digital values corresponding to angles within an octant. The octant output by the first read only memory and the angle output by the second read only memory together indicate the phase angle of the vector.

Abstract: A high-power high-isolation switch for high-power devices which switch power to one of several alternative output ports. Unwanted leakage is attenuated and high-isolation between the output ports is obtained. In addition, protection against burn-out during abnormally high leakage conditions is provided where the devices employed are not self protecting.

Abstract: A single-scan editor of bird echoes uses range rate to aid in identifying bird echoes. The range rate is preferably calculated from change in phase between one interpulse period to the next interpulse period and both unfiltered and MTI filtered signals are used for the calculation of change in phase. The unfiltered phase difference is used if the logarithm of the total power of the phase difference exceeds a predetermined threshold during at least one of the interpulse periods and if not, the MTI filtered phase difference is used if the total power of the MTI filtered signal exceeds a corresponding predetermined threshold. If neither threshold exceeds the corresponding threshold, no calculation is made. Due to the relationship between phase difference and range rate, several possible range rates correspond to most phase differences. Therefore, an occurrence of each of the possible range rates is counted over the course of a cycle.

Abstract: A dual stacked beam radar in which, after listening to low stack beams, and waiting for their echoes to return, a transmitter signal is transmitted on high, the high stack beams being listened to during the longer dead times during variable interpulse periods of the low stack beams.