Abstract: Series arcs in an ac circuit are discriminated from other phenomenon by analyzing the timing between pulses in a second derivative of the current signal. A first timer starts timing upon detection of a first pulse in the second derivative of current signal. Time out of the first timer starts a second timer which times a second interval or window during which a series arcing fault will generate a second pulse of opposite polarity to the first pulse. Detection of the first pulse followed by a second pulse of opposite polarity during the window sets a flip-flop to record the event. When a predetermined number of events are counted by a counter within a given time-period set by a third timer, an output signal indicating an arcing fault is generated. If the second pulse is generated before the window opens, or a third pulse occurs during the window, the flip-flop cannot be set so that other events such as the switching of a dimmer do not generate a false output signal.

Abstract: A sensor for use with time domain reflectometry systems to allow measurement of relative proportions of intermixed constituents having differing electrical permittivities contained in a fluid mixture. The sensor comprises a central primary electrode and a pair of adjacent outer secondary outer electrodes. The fluid mixture is located between the electrodes during sensing. A dielectric layer covers exposed sensing surfaces of the electrodes to electrically isolate the electrodes from the fluid mixture and to prevent dissipation of a time domain reflectometry signal propagated through the sensor.

Abstract: Pulse propagation analysis to ascertain whether an anomaly such as surface corrosion exists on a section of conductive member such as pipe. Anomalies such as surface corrosion result in localized velocity changes of pulses, due to inherent nonlinearities, propagating along a conductive member. These localized velocity changes exhibit themselves in changes in waveform, rise and fall time, amplitude, and time delay of a pulse with respect to a fixed time reference. To allow such anomalies to be located, two pulses are generated such that they intersect at intersecting locations along the conductive member. The resulting modified pulses are analyzed for perturbations indicative of localized velocity changes.

Abstract: An improved electric bulb short detection apparatus for a traffic signal controller capable of preventing an erroneous detection of an electric bulb short which is caused due to a voltage variation and the like, which includes an electric power control unit for driving a traffic signal light in response to an alternating current voltage supplied thereto; a voltage comparison circuit for comparing the the outputted voltage from an AC voltage source voltage with a reference voltage; a current detection unit for detecting a current of the electric power control unit in response to a comparison output signal from the voltage comparison circuit and for digitally-converting the current; and a central processing unit for judging whether an electric bulb is short by comparing a detection current value outputted from the current detection unit at every control step with a reference value and for controlling an electric power control circuit.

Abstract: A method for determining whether an electrochemical cell is substantially fully charged. The determination is made by ascertaining the rate of change of the impedance of the cell with changing frequency, at low frequency. A method for determining the state of charge of an electrochemical cell by comparing the impedance of the cell at two or more frequencies or by comparing the impedance of the cell, at a medium frequency, with the impedance at high frequency. Apparatus for generating output signals representative of the magnitude of resistive and reactive components of an impedance (30). The apparatus has a signal generator (70) for passing AC current through the impedance, and a synchronous demodulator circuit (88) for demodulating AC signal appearing across the impedance pursuant to passing the current through it. A phase shift circuit (130, 132, 136, 138, 140) selectively generates control signals in phase or 90.degree.

Abstract: Apparatus for detecting faults in buried conductors, a transmitter adapted to transmit electro-magnetic signals down the buried conductor; this signal is provided to increase an electro-magnetic path or corridor existing at the surface above the buried conductor. The invention also relates to a detecting means adapted to detect the electro-magnetic path or corridor, and to detect electro-magnetic patches formed in the path or corridor. These patches are located over the faults, and they are characterized by presence of an increased level of electro-magnetic energy caused by the faults. The transmitter means are adapted to transmit a composite signal comprising a carrier signal transmitted by a carrier signal means and a low frequency signal transmitted by a low frequency means. The carrier signal means comprise an RF carrier signal means and an audio tone signal means; the audio tone signal means are adapted to modulate signals transmitted by the RF carrier signal means.

Abstract: A probe card tester for detecting defects occurring as a result of integrated circuit processing of a substrate having a plurality of space to conductors with a contact at each end of each conductor, includes: a probe card tester including a set of parallel resistors for connecting at least one in parallel with each conductor and a set of series resistors for connecting together the ends of the conductors to form a series resistance and a number of probe elements, one corresponding to each end of each conductor, for interconnecting the parallel and series resistors with the conductors for detecting defects bridging the conductors.

Abstract: A piston position sensing system in which tabulated resonance width related information is stored in a form correlated with piston travel so that measured resonance width information can be compared with the stored information in determining piston position and compensation for the velocity of the piston is provided by correction for a time difference in serial sensing between the initial and the following extremes of a resonance signal as the piston moves. the compensation is developed from velocity information identified through previous and current processing cycles which assures reliability in detection of the subsequently sensed portion of the resonance signal envelope and enhanced sensitivity and accuracy through automatic application incrementally in a dynamic gain adjustment of the sensing system.

Abstract: A detector for detecting a secondary voltage supplied to a spark plug of an engine comprises a rubber tube mounted on a high tension cord and equipped with a detecting electrode, and a shield case or shield layer enclosing the rubber tube. The rubber tube is made up of first and second semicylindrical rubber members joined together into a tubular shape. The detecting electrode is U-shaped and has a middle portion embedded in the first rubber member and left and right ends which project, respectively, from left and right joint surfaces of the first rubber member, and are sheathed in grooves in left and right joint surfaces of the second rubber member. A lead wire is connected to one of the left and right projecting ends of the detecting electrode. This structure of the secondary voltage detector can facilitate the production process.

Abstract: A capacitive measuring device with a measuring electrode (3) arranged some distance from a counter-electrode (8), a dielectric material for analysis is arranged between the electrodes (3, 8), and a measuring current (IC) is supplied to the measuring electrode (3) and the capacitance-dependent capacitor voltage (UC) is measured and evaluated.

Abstract: A liquid conductivity measurement system is disclosed that accurately measures a liquid's conductivity over a range spanning at least several orders of magnitude using just a single sensor, but minimizing the adverse effects of capacitive and other non-linear factors on the conductivity measurement. The system includes a sensor having two spaced-apart electrodes immersed in the liquid and a drive signal source that applies to the sensor an ac electrical signal having a selected frequency and predetermined magnitude. A voltage detector monitors a sensor voltage signal across the sensor's two electrodes and produces a measurement of the liquid's conductivity. The drive signal source is configured to iteratively adjust the frequency of the ac electrical signal based on the sensor voltage signal, to optimize the liquid's conductivity measurement.

Abstract: A process is disclosed for ascertaining the microdefect levels of an electrophotographic imaging member comprising the steps of measuring either the differential increase in charge over and above the capacitive value or measuring reduction in voltage below the capacitive value of a known imaging member and of a virgin imaging member and comparing differential increase in charge over and above the capacitive value or the reduction in voltage below the capacitive value of the known imaging member and of the virgin imaging member.

Abstract: The method determines the phase difference in phase locked loops using clock signals (ts) generated in clock generators of communication equipment are synchronized to incoming reference clock signals (rts). The phase difference is determined by a rough phase difference and by a fine phase difference. The fine phase difference is represented by the plurality of delay elements (VE) of a delay line (VZL) that an incoming reference clock signal (rts) traverses up to the following clock signal (ts). A precise determination of the absolute delay time of a delay element (VE) is possible using the method, whereby components' tolerances cause considerable delay time differences of a delay element (VE) or, respectively, of the delay line (VZL). A considerable enhancement of the precision in determining the phase difference of cloak signals (ts) and reference clock signals (rts) and, thus, of the phase locked loops is achieved by the more precise determination of the absolute delay time of a delay element (VE).

Abstract: A voltage sensor detects a terminal voltage of a battery connected to a load and a current sensor detects a current flowing through the load. A voltage-current changing tendency calculation unit reads a detected voltage and a detected current detected by the voltage sensor and the current sensor and outputs, every predetermined period of time, plural data of the detected voltage and the corresponding detected current as dispersed data. A voltage-current approximating line calculation unit inputs the dispersed data and determines, based on the dispersed data, a voltage-current approximating linear function each time the predetermined period of time. A battery remaining capacity calculation unit determines, each time the voltage-current approximating linear function is determined, a remaining capacity of the battery based on the voltage-current approximating linear function.

Abstract: The present invention relates to a method of measuring residual capacity of a Ni/MH (nickel/metal hydride) cell by measuring the change in the electrical resistivity of a Ni/MH cell according to the change of the concentration of hydrogen in metal hydride. According to the present invention, a method for measuring residual capacity of a Ni/MH cell comprises the steps of measuring electrical resistivity of a first Ni/MH cell, and determining the residual capacity of the first Ni/MH cell (i) from a predetermined data of n-pairs of electrical resistivity values and residual capacity values of a second Ni/MH cell which has substantially the same composition as the composition of the first Ni/MH cell, or (ii) based on a predetermined functional relationship between the electrical resistivity and residual capacity of the second Ni/MH cell.

Abstract: A connector terminal checking device of the present invention comprises a base plate, a checking body movably mounted on the base plate, and a connector holder fixed onto the base plate, wherein the checking body further comprises a plurality of check pins aligned facing toward the connector holder, and the connector holder is provided with a terminal holding wall formed with a plurality of terminal position regulating sections, each for receiving a corresponding one of a plurality of terminal accommodating chambers of a connector to be checked, and also provided with a pair of connector sustainers shiftably urged by way of a resilient stuff, wherein by shifting the checking body toward the connector installed in the connector holder to bring the terminals in the connector into contact with the check pins, the terminals improperly inserted in the accommodating chamber are abutted against the terminal position regulating section and shifted to the properly inserted position.

Abstract: A method and device of readily detecting deterioration of a sample at low cost, which do not require any maintenance and monitoring of the sensor properties, and accordingly can decrease a load assigned to a system side. A conductive sensor having a pair of electrodes and a conductive film which is disposed between the pair of electrodes and is composed of a conductive material formed in a continuous region so as to connect the pair of electrodes at least electrically in its initial state is placed in an atmosphere where the sample is placed. The percolation transition of the conductive material of the conductive film occurs due to the grain growth thereof, accompanied by the deterioration of the inorganic material composing the sample due to the grain growth thereof. By monitoring the variation in electric resistance of the conductive sensor due to the percolation transition of the conductive material, the deterioration of the sample can be detected.

Abstract: A portable measuring device for measuring electromagnetic radiation reflection. The device has a holder, a transceiver, and a display. The transceiver is movably mounted to the holder. The holder can be moved to several locations on a member being tested. The transceiver is moved up and down on the holder through the peaks and valleys of the reflected electromagnetic wave, in and out of phase, passing through and detecting the maximum reflected energy point. A system can be provided that uses the measurement at a predetermined frequency in comparing the measured property to a characteristic curve of the property for the material of the member being tested. The system can be used to plot a three-dimensional graph of surface reflection of the electromagnetic energy.

Abstract: A standard resistor having a known resistance value is connected to one transistor in a drive IC. The drive IC has a plurality of transistors each controlling the on/off of a heating element. The saturation voltage of each transistor is generally the same. One of a plurality of transistors is turned on, and a discharge time required for a capacitor to discharge via a standard resistor or via each heating element and lower its voltage to a predetermined voltage is measured. The resistance value of each heating element is determined from a ratio of a discharge time via each heating element to a discharge time via the standard resistor and the resistance value of the standard resistor. A difference between the standard resistance value and a resistance value of each heating element generates a bias heat energy error during bias heating and an image heat energy error during image heating. In accordance with these heat energy errors, bias data for generating a heat energy immediately before coloring is corrected.

Abstract: The connector checking device of the present invention comprises: a connector holding member 6, and a checking device main body 3 detachably mounted from the connector holding member, wherein the main body is further provided with a plurality of check pins 11 connected with an electric circuit and urged toward the connector holding member by a coil spring 12, and a spacer removing piece 14 formed with a hook 14c which is also urged toward the connector holding member by another coil spring 15.