Abstract: A system and method for detecting ground fault currents in multi-phase power systems. The system and method utilize a gapped core having a central opening. The central opening allows the multiple conductors, e.g. three conductors, to pass therethrough as a group. A sensor, such as a Hall generator, is disposed in the gap of the core and provides an output signal when the current flowing through the multi-phase conductor is unbalanced. The signal output is designed to be proportional to the detected ground fault current.

Abstract: An arbitrary waveform generator (AWG) generates an output signal that linearly ramps between discrete levels to approximate a smoothly varying waveform. The AWG includes a digital-to-analog converter (DAC) formed by a set of N ramp generators, with each ramp generator producing output currents that ramp at adjustable rates between discrete levels in response to a change in state of an input waveform data bit. The output currents of all N ramp generators of the DAC, which have separately weighted magnitude levels, are summed and converted to a proportional voltage to produce the AWG's output signal.

Abstract: The invention relates to a device for detecting the position of a magnet which is positioned so that it is moveable (3, 23, 24) to produce a magnetic field (6) through a ferromagnetic wall (1, 29), a magnetic field sensor (10, 21, 21′) being situated in front of said wall. When said magnet (3, 23, 24) is moved in relation to said wall (1), the lines (6) of the field build up a useful flux (6) which progresses in said wall (1, 29). Said useful flux has magnetic remanence (7) which is retained after the magnet (3, 23, 24) has passed by, is aligned along the movement axis of the magnet (3, 23, 24) in accordance with the polarity, and builds up a fringing flux (12) to the front side of the wall (1, 29) where the magnetic field sensor (10, 21, 21′) is positioned. Outside of said wall, the fringing flux (12) is opposed and is aligned with the useful flux (6).

Abstract: Resistivity data acquired at two different epochs using different types of tools are jointly inverted. For example, a multiple propagation resistivity (MPR) tool is run first, preferably at several frequencies and several transmitter-receiver spacings. At a later epoch, an induction tool may be run, preferably on a wireline. The joint inversion process identifies bed boundaries based on inflection points in the propagation resistivity and induction logging raw data. An initial guess for an uninvaded earth model is generated using the selected bed boundaries and the apparent raw resistivity values. An inversion run using shallow measurements of propagation resistivity logging data is performed to estimate a resistivity structure representative of the near borehole zone resistivity (invaded zone). The bed boundary positions of the layers are also updated as part of the inversion process. Synthetic data for both the shallow and deep measurements are generated to delineate the invasion zones.

Abstract: An interface apparatus having a plurality of self-aligning coaxial connectors for substantially simultaneous interconnection with a plurality of connectors on a unit under test includes a base member, a first interface and a second interface. The first and second interfaces are spaced apart to receive the unit under test. At least one of the first and second interfaces is slidably movable on the base member for movement into engagement with the unit under test that is positioned between the interfaces. At least one of the first and second interfaces has a plurality of self-aligning coaxial connectors that are positioned to interconnect with the plurality of connectors on the unit under test. An urging means is provided for moving the interfaces so that the self-aligning coaxial connectors are moved into mating engagement with the plurality of connectors on the unit under test that is positioned between the interfaces.

Abstract: The present invention provides a wide band IQ splitting apparatus suitable for using in a spectrum analyzer. A quadrature oscillator 30 generates a pair of quadrature signals. An amplitude and phase adjuster 32 receives the quadrature signals and adjusts the balances of the amplitude and the phase between them. An analog splitter 20 mixes an analog IF signal with the pair of quadrature signals for splitting the analog IF signal into analog I and Q signals. First and second analog to digital converters 22 and 24 convert the analog I and Q signals into digital I and Q signals, respectively. A control and processing circuit detects the imbalances of the amplitude and phase between the digital I and Q signals for controlling the amplitude and phase adjuster 32. The amplitude and phase adjuster 32 is previously calibrated. For this first calibration, the analog splitter 20 receives a first calibration signal instead of the analog IF signal.

Abstract: A cartridge (10) includes a chuck plate (12) for receiving a wafer (74) and a probe plate (14) for establishing electrical contact with the wafer. In use, a mechanical connecting device (90) locks the chuck plate and the probe plate fixed relative to one another to maintain alignment of the wafer and the probe plate. Preferably, electrical contact with the wafer is established using a probe card (50) that is movably mounted to the probe plate by means of a plurality of leaf springs (52.) The mechanical connecting device is preferably a kinematic coupling including a male connector (94) and first and second opposed jaws (122, 124.) Each of the jaws is pivotable from a retracted position in which the male connector can be inserted between the jaws and an engaging position in which the jaws prevent withdrawal of the male connector from between the jaws. The male connector is movable between an extended and a retracted position, and is biased towards the retracted position.

Abstract: The diagnosis method of deterioration of electric power cable is that which diagnoses the deterioration accurately without a especial effort to reduce the harmonics in an electric power source equipment for test. Loss current component, which is obtained by rejecting the capacitive component of frequency f1 contained in the total current flowing in the insulation of the electric power cable, when superimposing a first voltage V1 of frequency f1 and a second voltage V2 of frequency f2 (V1≧V2) to an electric power cable, is measured. Further the current components and the frequency components contained in the current is investigated. The deterioration diagnosis is implemented by frequency components excepting the frequency f1, f2 and the their harmonic.

Abstract: An apparatus and a method of detecting the capacity of the standby power. First, the components that are supplied with working voltage from the standby power are switched to the main power by a switch circuit. Then a control unit activates a dummy-loading circuit, thereby a coupling a loading device to the standby power. A voltage monitoring circuit monitors variations of the standby power to judge the capacity of the standby power, by which the switch circuit decides whether the standby power is activated or not. When detecting the capacity of the standby power, a switch circuit is needed to prevent variations of the standby power from affecting the normal operation of the essential circuit, and the standby power is supplied as operating power.

Abstract: For determining the quantity of an electrically conductive product contained in a reservoir made of electrically insulating material, having at least one storage cavity: a resonant circuit is formed, including a capacitive arrangement comprising at least part of this reservoir; a processing procedure is defined, consisting of identifying, from a plurality of signals corresponding to different frequencies, the value of a characteristic of this resonant circuit, deriving from this value of the characteristic a measurement of the resistance constituted by the product contained in the reservoir in the said capacitive arrangement and deriving therefrom the instantaneous value of an item of information representing the quantity of product contained in the reservoir from a pre-established correlation law; and a least one determination cycle is effected, consisting of triggering the measurement procedure and the processing procedure, and capturing the instantaneous value of the said item of information.

Abstract: In a method of evaluating the reliability of a thin film transistor (TFT), time coefficient &bgr;, voltage coefficient d and temperature coefficient &phgr;0 are experimentally produced from −BT stress tests, and the life of a TFT under −BT stress conditions is evaluated using the following expression: τ = t 0 ⁡ ( Δ ⁢   ⁢ V th ⁢   ⁢ τ

Abstract: The 4 mA-20 mA type or 0-20 mA type current loop connects an analog sensor (1) to an acquisition system (3), respectively carrying a sensor current (Ic) and an acquisition current (Ia). A test circuit is connected in parallel with the current loop to inject a superposition current (Is) into said loop, which current is superposed on the sensor current (Ic) or on the acquisition current (Ia). In a first embodiment, a variable voltage generator (7) injects the superposition current (Is) by adding it to the acquisition current (Ia), thereby making it possible to check a low-current threshold of the acquisition system (3). In a second embodiment, a variable current regulator injects the superposition current (Is) by adding it to the sensor current (Ic), thereby making it possible to check a high-current threshold of the acquisition system. The high- and low-current thresholds of the acquisition system are tested without opening the current loop.

Abstract: A preferred embodiment of the present invention includes a system for detecting a presence of a macromolecule having one or more resonant frequencies. The system includes a pulse generator (a T-wave generator in the most preferred embodiment) for generating a detection profile having a detection set of T-waves and applying the detection profile to a sample including the macromolecule, at least one T-wave having a center frequency substantially centered on one of the resonant frequencies of the macromolecule, a detector for receiving the detection profile after the application of the detection profile to the sample, an analyzer, coupled to the detector, for determining a T-wave absorption profile by identifying which T-waves of the set of T-waves have been wholly or partially absorbed by the sample and to subsequently identify the macromolecule by use of the absorption profile.

Abstract: A mode selection method for signal analyzers having alternative swept and Fast Fourier Transform (FFT) modes of operation enables tradeoffs between measurement speed and dynamic range to be optimized in selecting between the alternative operating modes. The method includes setting the signal analyzer to either a manual state or an automatic state according to a first input to a user interface. When the manual state is set, the analyzer is operated in either the swept operating mode or the FFT operating mode according to a second input to the user interface. When the automatic measurement state is set, a third input to the user interface determines whether measurement speed or dynamic range is optimized. Measurement speed is optimized according to a first optimization scheme and dynamic range is optimized according to a second optimization scheme.

Abstract: A circuit generating a test mode instructing signal includes a test mode register circuit which is set to a state disabling instruction of a test mode in a standby state. An intended test mode can be accurately selected even when the test mode is instructed in accordance with a plurality of external signals varied in timing from each other. A semiconductor device allows accurate and efficient execution of the test without requiring increase in area occupied by an array.

Abstract: Apparatus and method is provided for performing detailed mine detection over variable terrain. An articulated robotic scanner comprises an articulated arm mounted to any vehicle such as a robot. One or more mine detectors mounted at the end of the arm. The arm operates autonomously to repetitively sweep the mine detector in ever forward advancing side-to-side arcs over the terrain. The vehicle can operate autonomously or be tele-operated. The position of the mine detector is monitored and known with respect to a known coordinate system. Sensors measure their position relative to the ground and relative to known co-ordinates of the mine detector. A controller determines the relative position of the ground and the mine detector and dynamically adjusts the mine detector's position to maintain a constant separation over variable terrain without ever contacting the ground or objects thereon.

Abstract: Methods are provided for detecting and locating leaks in liners used as barriers in the construction of landfills, surface impoundments, water reservoirs, tanks, and the like. Electrodes are placed in the ground around the periphery of the facility, in the leak detection zone located between two liners if present, and/or within the containment facility. Electrical resistivity data is collected using these electrodes. This data is used to map the electrical resistivity distribution beneath the containment liner or between two liners in a double-lined facility. In an alternative embodiment, an electrode placed within the lined facility is driven to an electrical potential with respect to another electrode placed at a distance from the lined facility (mise-a-la-masse). Voltage differences are then measured between various combinations of additional electrodes placed in the soil on the periphery of the facility, the leak detection zone, or within the facility.

Abstract: A load board is attached to the test head of a semiconductor tester and has a receptacle surface oriented substantially perpendicular to a Z-axis and presented toward a handler location. An adaptor plate is attached to a Z axis abutment structure and has a surface at a predetermined Z axis position relative to the receptacle surface of the load board, the surface of the adaptor plate being presented toward the handler location. At least three spacers are attached to the adaptor plate and project from the surface of the adaptor plate.

Abstract: An electrochemical field probe for measuring solute concentrations of elements dissolved in a liquid, such as a molten metal bath, generally including a base having a first end, a second end, an external surface, and extending about a longitudinal axis, a reference electrode positioned between the first and second ends of the base, and a glassy electrolyte positioned adjacent the reference electrode, wherein the reference electrode is a Mo substrate coated with a electrode reference material selected from a group including NiAl, graphite, Cr, a compound of Mo and Mo3Si, a compound of Cr and Cr2O3, a compound of Ti and TiN, a compound of Ti and TiS, and a compound of Th and ThP and the glassy electrolyte is selected from a group including a compound of 38% CaO, 42% SiO2, and 20% Al2O3, soda glass, pyrex powder, and a pre-fused mixture of cryolite (Na3AlF6) admixed with approximately 5% to 10% CaF2 (fluorspar) and approximately 4% to 7% Al2O3.

Abstract: A measurement system is provided for measuring Vil and Vih of integrated circuits (ICs). The measurement system includes a computer that transmits a control signal to a power supply, which in turn transmits a corresponding applied voltage to the input terminal of an IC. The output terminal of the IC is connected to a parallel port of the computer, thereby forming a feedback loop that allows automatic measurement of Vil and Vih.