Abstract: This learning device is provided with: a simulation execution unit that, by using electromagnetic field analysis simulation, determines a reflected wave spectrum obtained when electromagnetic waves are emitted from a reader to an identification target; and a machine learning unit that, by using training data in which the reflected wave spectrum calculated by the simulation execution unit and an attribute thereof are defined as a set, performs a training process on a learning model by machine learning. The simulation execution unit generates a plurality of the reflected wave spectra belonging to the same attribute by variously changing various parameters related to the identification target from reference parameters. The machine learning unit performs a training process on the learning model by machine learning by using, as training data, the plurality of reflected wave spectra obtained for each attribute.

Abstract: Disclosed a passive wireless sensor for detecting discrete droplets and bubbles. A first inductor channel and a second inductor channel are disposed opposite each other to form a capacitor channel, the first inductor channel is connected to the second inductor channel to form a resonant circuit. When a detection object passes through the detection channel, the permittivity between the first inductor channel and the second inductor channel changes and consequently a capacitance value of the capacitor channel changes, thus resulting in a change in resonant frequency of the resonant circuit. A readout device is used to read the resonant frequency of the resonant circuit and perform detection according to the resonant frequency to obtain information of a corresponding detection object.

Abstract: A diaphragm pump, in particular for use as a detergent dosage pump, comprises a pump head, a fluid chamber adjacent to the pump head, a diaphragm defining a wall of the fluid chamber and reciprocatingly movable, at least a suction check valve and a dosing check valve, a control unit, and a detector unit for detecting a fluid inside the fluid chamber. The diaphragm pump according to the invention offers increased process reliability.

Abstract: A wireless charging system and method are provided, that are capable of simultaneously charging multiple mobile devices, providing high power transfer efficiency for multiple mobile devices located at any position and orientation, and minimizing electromagnetic radiation from a transmitting (TX) coil and a receiving (RX) coil. The method and structure reduce electromagnetic interference (EMI) radiation by shunting in-phase currents flowing in a wireless power transmitting unit (TX unit) and a wireless power receiving unit (RX unit) of a wireless charging system.

Abstract: A wireless remote sensor (110) that is powered by an inductive transmitter (112) and is configured to produce an oscillating wave that varies based on one or more sensed parameters. The oscillating wave is communicated to the inductive transmitter (112) by reflected impedance, where it can be detected to determine the sensed value(s). In another aspect, the present invention provides a wireless remote sensor with a Wheatstone bridge arrangement having an internal resonant circuit to produce an electromagnetic field indicative of the sensed value. In a third aspect, the present invention provides a wireless remote sensor with optical feedback from a reference circuit and a sensor circuit. In a fourth aspect, the present invention provides a wireless remote temperature sensor having coils printed on a material with a high coefficient of thermal expansion so that the size and/or shape of the coils varies as the temperature increases or decreases.

Abstract: Provided is an apparatus capable of distinguishing a kind of a powder deposited on an inner surface of a pipe, and more precisely measuring a thickness of the powder deposited on the inner surface of the pipe. The apparatus for measuring a thickness of a powder deposited on an inner surface of a pipe, includes a pair of the first electrodes disposed adjacent to one portion of the inner surface of the pipe and used to measure a first capacitance and thus to distinguish a kind of the powder, and a pair of second electrodes disposed in the pipe to be spaced from each other and to be symmetrical with respect to a center portion of the pipe and used to measure a second and a third capacitance.

Abstract: Apparatus for determining and/or monitoring at least one limit value of a process variable of a medium in a container, comprising at least one sensor unit for registering a measured value dependent on the process variable and at least one electronics unit for producing a measurement signal dependent on the process variable. The invention is distinguished by features including that the apparatus is embodied to draw energy via a voltage output and a digital input of a recorder apparatus or a process control system.

Abstract: Processes and apparatuses are provided for contactless measuring or monitoring in-situ and in real time composition or other electromagnetic impedance correlated properties of liquid or gaseous substances or bulk materials. One or more apparatus may include a resonance type impedance sensor having at least two coils, at least one coil of the at least two coils being at least one excitation coil connectable to at least one alternating current source with frequency sweep, at least one other coil of the at least two coils being at least one sensing coil connectable to at least one data processing system. The one or more methods may include calculating changes in amplitude and resonant frequency induced by electromagnetic interaction between said sensor and object to determine impedance of said object under test; and matching said impedance with predetermined calibration data to determine said chemical or physical properties of said object under test.

Abstract: A method for in situ monitoring of a membrane of a membrane separation system comprises measuring a complex impedance of the membrane at a plurality of frequencies to provide an indication of the electrical conduction and electrical polarization properties of the membrane. The membrane based separation system for removing or reducing the concentration of materials carried in a fluid including a separation membrane has a first pair of electrodes separated by the membrane and arranged for measurement of the complex impedance of the membrane at a plurality of frequencies to provide the indication of the membrane properties. There may also be a second pair of electrodes separated by the membrane for injecting the stimulus current such that the injecting and monitoring functions are separated.

Abstract: The invention relates to a method and a monitoring system for automatically actuated, in particular power-driven closing covers, for example boot lids of motor vehicles. The invention also relates to a method and a detection system for detecting the presence of objects per se. The aim of the invention is to provide solutions for the implementation of a reliable safety system.

Abstract: Permittivity sensor and method comprising: an oscillator (L,40) having operating characteristics (F,V); permittivity sensing element (30) coupled to the oscillator and arranged to alter the operating characteristics of the oscillator in response to changes in permittivity presented to the permittivity sensing element; a reference element (110) switchably (220) coupled to both the oscillator and the permittivity sensing element and arranged to alter the operating characteristics of the oscillator. Method of measuring the composition of a fuel comprising the steps of: measuring a real permittivity of the fuel; measuring an imaginary permittivity of the fuel; determining a proportion of biodiesel in the fuel based on the measured real permittivity. Determining a proportion of unrefined oil in the fuel based on the measured imaginary permittivity.

Abstract: An occupant detection system that includes an electrode arranged proximate to an expected location of an occupant for generating an electric field between the electrode and the occupant proximate thereto. An electrical network coupled to the electrode forms a resonant circuit that includes the occupant as part of the resonant circuit. A controller coupled to the resonant circuit is configured to determine a resonant frequency of the resonant circuit indicative of an occupant presence, and a network signal magnitude at the resonant frequency indicative of a humidity value proximate to the electrode. 7. A method for detecting a vehicle applies an excitation signal to the resonant circuit, determine a resonant frequency of the resonant circuit and determines a humidity value based on a network signal magnitude at the resonant frequency.

Abstract: An analyte concentration, in a sample fluid, is determined by differential measurement. Two or more capacitive field effect sensors have an identical basic structure and are arranged in a shared measuring cell. One of the sensors forms a measuring sensor with an active transductor layer. Another sensor forms a reference sensor without an active transductor layer. The sensors are contacted with the sample fluid and the sensors, have an associated reference electrode, or have a shared reference electrode. A bias voltage composed of an electric DC voltage and a superimposed AC voltage is applied between each sensor and associated reference electrode(s) Capacitance changes due to the analyte are eliminated by controlling the bias voltage applied to the measuring sensor in a closed control loop. A measuring signal is obtained by calculating a difference between voltage values representative of DC voltage potentials applied to the measuring sensor and reference sensor, respectively.

Abstract: A patch-clamp system employs a high-frequency characterization of cell wall membranes. Changes in the frequency response of a tank circuit incorporating the cell wall membrane impedance provides highly sensitive and highly time-resolved measurements of ion channel activity.

Abstract: Methods and sensors for selective fluid sensing are provided. A sensor includes a resonant inductor-capacitor-resistor (LCR) circuit and a sensing material disposed over the LCR circuit. The sensing material includes a coordination compound of a ligand and a metal nanoparticle. The coordination compound has the formula: (X)n-M, where X includes an alkylamine group having the formula (R—NH2), an alkylphosphine having the formula (R3—P), an alkylphosphine oxide having the formula (R3P?O), an alkyldithiocarbamate having the formula (R2NCS2), an alkylxanthate having the formula (ROCS2), or any combination thereof, R includes an alkyl group, n is 1, 2, or 3, and M includes the metal nanoparticle of gold, silver, platinum, palladium, alloys thereof, highly conductive metal nanoparticles, or any combination thereof. The sensing material is configured to allow selective detection of at least six different analyte fluids from an analyzed fluid mixture.

Abstract: An oscillating signal of relatively precise frequency is generated by tuning an oscillator using an external stable oscillating source as a reference. Calibration logic is included to compare a signal from the local oscillator to the reference signal and vary the local signal to a desired frequency. In one embodiment, a binary search algorithm is used to tune the local oscillator. The local oscillating signal can be sent to one or more circuits including at least one sensor of a touch sensitive panel for detecting touch events.

Abstract: The invention relates to a method and a monitoring system for automatically actuated, in particular power-driven closing covers, for example boot lids of motor vehicles. The invention also relates to a method and a detection system for detecting the presence of objects per se. The aim of the invention is to provide solutions for the implementation of a reliable safety system.

Abstract: A system for selectively determining at least two analytes, comprising at least one resonant sensor circuit comprising a sensing material that predictably affects the resonant complex impedance response of a sensor electrode, wherein the sensing material having at least two material properties that change upon exposure to two or more analytes; and a processor that generates a multivariate sensor response pattern that is based at least in part on a change in the two material properties of the sensing material and a sensing device and methods adapted to detect an analyte using the same sensor system.

Abstract: A patch-clamp system employs a high-frequency characterization of cell wall membranes. Changes in the frequency response of a tank circuit incorporating the cell wall membrane impedance provides highly sensitive and highly time-resolved measurements of ion channel activity.

Abstract: According to some embodiments, motor-tuned nuclear magnetic resonance (NMR) probes may be tuned manually without overcoming the tuning motor holding force. An NMR probe includes a switchable manual-mode/motor-driven mode capacitance-adjustment assembly for adjusting the capacitance of a variable capacitor connected to an NMR RF coil. The capacitance-adjustment assembly includes a tuning shaft coupled to the variable capacitor through a gear assembly, and a mode-switching coupler coupled to the tuning shaft. The mode-switching coupler includes a first terminal coupled to a piezoelectric motor, and a second terminal coupled to the tuning shaft. In the manual mode, a user pushes up the tuning shaft, decoupling the two terminals of the mode-switching coupler and thus decoupling the motor from the tuning shaft. The user then manually rotates the tuning shaft. In the motor-driven mode, a spring tensioner presses the two terminals of the mode-switching coupler together, coupling the motor to the tuning shaft.

Abstract: A semiconductor device includes a semiconductor chip and a wiring substrate. The wiring substrate is configured to be electrically connected to the semiconductor chip, and have a plurality of terminals arranged on an surface opposite to a surface on which the semiconductor chip is mounted. The plurality of terminals includes a plurality of first terminals configured to be arranged closely to each other, and a plurality of second terminals configured to be arranged so as to surround the plurality of first terminals. The plurality of second terminals is provided such that terminals of the semiconductor chip are connected to outer terminals through the plurality of second terminals. Each of the plurality of first terminals is not provided with a metal ball, while each of the plurality of second terminals is provided with a metal ball.

Abstract: Inconsistencies in a resin-based part are detected using a capacitive coupling probe having a tuned circuit and an impedance matching element. An alternating electric field produced by the probe penetrates the part. Inconsistencies in the resin part result in changes in the resonance of the circuit which are detected by a network analyzer.

Abstract: Systems and methods for determining a total acid number associated with biodiesel in a mixture of biodiesel and petrodiesel are provided. The method includes receiving an oscillatory signal at an inductance-capacitance-resistance circuit. The circuit has a sensing element fluidly communicating with the mixture of biodiesel and petrodiese. The method further includes generating a resonant current at a resonant frequency utilizing the circuit in response to the oscillatory signal. The method further includes determining a dielectric constant value indicating a dielectric constant associated with the biodiesel in the mixture based on the resonant frequency of the resonant current, utilizing a microprocessor. The method further includes determining a concentration value indicating a concentration of the biodiesel in the mixture based on an amplitude of the resonant current and the dielectric constant value, utilizing the microprocessor.

Abstract: Inconsistencies in a resin-based part are detected using a capacitive coupling probe having a tuned circuit and an impedance matching element. An alternating electric field produced by the probe penetrates the part. Inconsistencies in the resin part result in changes in the resonance of the circuit which are detected by a network analyzer.

Abstract: When using solenoid coils in an explosion-hazard environment, in order that no sparks are produced in the event of a discontinuity in an electrical line leading to the solenoid coil, two or more identical zener diodes are connected in parallel with one another and to the solenoid coil. In order to verify the operability of all the zener diodes which are connected in parallel with one another and to the solenoid coil, the electrical values of the zener diodes and of the solenoid coil are measured before assembly. The total capacitance of the circuit arrangement is measured after assembly. The capacitance of the solenoid coil is subtracted from the total capacitance, and the remaining value is divided by the number of parallel-connected zener diodes. The result is compared with the capacitance of a single zener diode, with the magnitude of the difference between these values being used as a criterion for the operability of the zener diodes.

Abstract: A method for measuring a capacitance of a device under test is provided that includes selectively charging and discharging a first conductor with a first set of p and n element-pairs in response to a voltage potential applied to the first set of p and n element-pairs. The method further includes selectively charging and discharging a second conductor with a second set of p and n element-pairs in response to a voltage potential applied to the second set of p and n element-pairs. Currents are measured at drains associated with the first set of p element-pairs as the first and second conductors charge and discharge such that a capacitance associated with the first conductor may be determined that is based on the drain currents.

Abstract: A sensing system for a target includes a member with an embedded charge, at least one input electrode, at least one output electrode, at least one common electrode, one or more probes, an input system, and an output monitoring system. The input and output electrodes are spaced from and on substantially opposing sides of the member from the common electrode. At least one of the member and the input and output electrodes is movable with respect to the other. The probes which engage with the target hazardous substance are connected to the at least one of the member and the input and output electrodes which is movable with respect to the other. The input system is coupled between the at least one input electrode and the at least one output electrode and provides an input signal. The output monitoring system is coupled between the at least one output electrode and the at least one common electrode and detects a change in an output signal when the target engages with the movable member or electrode.

Abstract: Measurement of the permittivity of thin films is facilitated through the use of a short cylindrical metal cavity containing parallel plates between which a specimen to be measured is placed. The use of such parallel plates contained within such a cavity is particularly advantageous when swept frequency measurement methods utilizing frequency ranges from 0 to 20 GHz are employed. A test fixture which is preferred for use in providing such a cavity is disclosed as are methods of using the test fixture.

Abstract: A method for analyzing a dielectric medium comprises the step of measuring, at one or more frequencies, the capacitance between a pair of electrodes immersed in the dielectric medium. The proportion of the or each capacitance measurement due to electrode polarization capacitance and/or to the residual capacitance of the dielectric medium is then determined using capacitance measurements made between the electrodes at a first frequency and at a second frequency, the ratio of the respective polarization capacitances at these two frequencies being predetermined. An apparatus for performing the method is also disclosed.

Abstract: A projectile fuze detects transitions between target layers by an electronic antenna radiating laterally into the target material and coupled to a pullable oscillator whose frequency shifts as the target material changes while the projectile penetrates. A frequency shift threshold detector relates the observed frequency shifts to a stored target profile to detonate the projectile after the desired layer penetration.

Abstract: Measurement of the permittivity of thin films is facilitated through the use of a short cylindrical metal cavity containing parallel plates between which a specimen to be measured is placed. The use of such parallel plates contained within such a cavity is particularly advantageous when swept frequency measurement methods utilizing frequency ranges from 0 to 20 GHz are employed. A test fixture which is preferred for use in providing such a cavity is disclosed as are methods of using the test fixture.

Abstract: The present invention comprises a sensor apparatus used to measure surface mechanical loading such as a liquid loading that compensates for static capacitance in the sensor. The sensor includes a resonator and a variable capacitance device. The resonator and its concomitant circuitry has a static capacitance and is adapted to increase its motional impedance when exposed to surface mechanical loading. The variable capacitance device is connected to the resonator and is adapted to compensate for the static capacitance, whereby the range and linearity of the sensor apparatus are improved.

Abstract: A paving material analyzer system is disclosed that uses paving material impedance to determine paving material density. The invention also includes a method for analyzing paving material, in particular, determining paving material density. The paving material density can also be used to determine a percentage of maximum compaction. A paving material analyzer is also disclosed that determines paving material density regardless of moisture presence on the paving material.

Abstract: Between a reference voltage point and the emitter or the source of a transistor of which the collector or the drain is connected to a power source and to which an signal is input at its base or its gate, DC current passing means for causing a current to flow from the emitter or the source to the reference voltage point and a capacitor connected to the reference voltage point at one end and charged with a voltage generated in the DC current passing means are provided. A detection output for the signal is obtained from the emitter or the source of the transistor, or the other end of the capacitor.

Abstract: An apparatus for detecting seated condition for toilet seat which detects whether the change in input voltage of determining circuit, over predetermined time, in response to electrostatic capacity is existed or not. When the change is existed, the present apparatus computes and renews the set value 1 for detecting un-seated condition and the set value 2 for detecting seated condition based on the changed input potential.Accordingly, the present apparatus is the apparatus for detecting whether a human is seated or un-seated on a toilet seat using electrostatic capacity and the present invention can reduce the error in detection caused by the change in electrostatic capacity owing to a person, temperature and humidity.

Abstract: A tubular single-layer winding coil is installed on the outer periphery of a thin wall portion of a cylindrical container case and a columnar electrode is provided at the center of the inside of the cylindrical container case. A fuel channel is formed between the coil and the electrode so that the permittivity of fuel flowing through the fuel channel is detected from the electrostatic capacity therebetween. Further, variation of the electrostatic capacity due to the temperature characteristics of the fuel is compensated by the temperature characteristics of the permittivity of the thin wall portion of the sensor unit. Furthermore, variation of the electrostatic capacity due to the temperature characteristics of the fuel is compensated by the temperature compensation capacitor which is connected with the single layer winding coil in parallel.

Abstract: A tubular single-layer winding coil is installed on the outer periphery of a thin wall portion of a cylindrical container case and a columnar electrode is provided at the center of the inside of the cylindrical container case. A fuel channel is formed between the coil and the electrode so that the permittivity of fuel flowing through the fuel channel is detected from the electrostatic capacity therebetween. Further, variation of the electrostatic capacity due to the temperature characteristics of the fuel is compensated by the temperature characteristics of the permittivity of the thin wall portion of the sensor unit. Furthermore, variation of the electrostatic capacity due to the temperature characteristics of the fuel is compensated by the temperature compensation capacitor which is connected with the single layer winding coil in parallel.

Abstract: This invention concerns an apparatus for checking the thickness and uniformity of a coating made of conducting material deposited on an elongated insulating body, this apparatus comprising:a sensor sensitive to the presence of the elongated body and forming part of an electrical circuit powered by a power supply voltage (24),measurement instruments (25) to measure an electrical quantity that is a function of the thickness of the conducting coating, at the output of the circuitequipment for processing the electrical quantity to deduce the thickness of the conducting coating,wherein the sensor consists of a condenser (10) containing two plates separated from each other by an air gap containing a dielectric material, this condenser being adapted to enable the elongated body to pass through the air gap.

Abstract: A dielectric constant detecting apparatus comprises an LC circuit for shifting the phase of a high frequency voltage signal according to the dielectric constant of a liquid which passes between the coil and the electrode of the LC circuit. A resistor is connected between the LC circuit and at least one part of a phase comparator. The phase comparator detects the phase shift between high frequency signals provided at both ends of the resistor. The resistor and at least one part of the phase comparator are integrally included in an insulator. The output of the phase comparator is compared with a predetermined phase shift value. A voltage control device adjusts the high frequency voltage signal from the voltage applying device so that the phase shift detected by the phase comparator is further adjusted toward the predetermined phase shift value.

Abstract: A particulate moisture measurement gauge of the type using a resonant electric circuit connected to a diode detector and to an AC signal generator having a frequency near the resonant frequency of the resonant circuit and in which the resonant circuit is electrically coupled to the particulate by a capacitor having the particulate as its dielectric. A probe is formed as a transmission line having a length which is approximately an integral number of one quarter wave lengths long. One end of the transmission line is connected to the circuitry and its opposite, moisture sensing end is immersed in the particulate. Preferably the probe is a rigid, conductive tube with a central rod having a ceramic insulator sealing its moisture sensing end and the circuitry housed in its opposite end.

Abstract: It is an object of the present invention to prevent variations in sensitivity of the sensor circuits of the respective channels by equalizing the power of oscillation frequency signals to be distributed/supplied from one oscillation circuit to the sensor circuits of the respective channels. Multi-channel sensor circuits are arranged with a common oscillation circuit. A high-impedance conversion circuit is connected to the output terminal of the oscillation circuit. A first impedance matching circuit for performing impedance matching of resonance circuits of the respective channels with reference to the oscillation circuit is arranged on the output side of the high-impedance conversion circuit. Second impedance matching circuits for performing impedance matching of the oscillation circuit with reference to the resonance circuits are connected at the input terminals of the resonance circuits of the respective channels.

Abstract: A plurality of sensor circuits each including an oscillator circuit, a detection electrode, and a ceramic resonator for changing a resonance frequency in accordance with a change in small electrostatic capacitance detected by the detector electrode and outputting a detection signal corresponding to a change in resonance frequency are formed on a circuit board. Detector electrode surfaces A.sub.1 to A.sub.4, B.sub.1 to B.sub.4, and C.sub.1 to C.sub.4 of the first to third sensor circuits are formed on the upper surface of the circuit board in a divisional manner. The detection surfaces of the respective sensor circuits are arranged to have codes in the scanning direction of an object to be detected. The fixed capacitances of the detection surfaces are decreased, and a change of state of the object can thus be detected at a high resolution.

Abstract: A security tag for use with an electronic security system is used for attachment to an article having an inherent capacitance such as meat. The security system includes a transmitter for transmitting into a surveilled area electromagnetic energy having a center frequency within a predetermined detection frequency range and a receiver for detecting within the surveilled area the presence of a security tag resonating at a frequency within the detection frequency range in response to the electromagnetic energy. The tag includes a generally planar dielectric substrate having a first side and a second side. Circuitry on the substrate establishes a resonant circuit having a resonant frequency which is initially a predetermined frequency interval above the center frequency of the detection frequency range.

Abstract: The invention relates to a sensor with two electrodes and a non-conducting iaphragm arranged between them. The electrodes have an insulating coating, which preferably comprises a metal oxide, mixed metal oxide, metal nitride, inorganic insulating material or fluorocarbon and the non-conducting diaphragm a metal oxide, mixed metal oxide, inorganic or organic insulating materials. As a function of the intended use, the diaphragm and electrode coating are porous (for measurements in non-aqueous liquids) or non-porous (for measurements of aqueous liquids). It is also directed at a process for measuring the characteristics of a liquid with the sensor according to the invention, as well as to the use of the sensor for the continuous or discontinuous investigation of liquids.

Abstract: Disclosed is a method of detecting a variation in stray capacitance by use of a PLL circuit.

Abstract: A ceramic resonance type electrostatic sensor apparatus with an oscillator at a fixed frequency including a first ceramic resonator which has a fixed resonance frequency, a detecting unit for detecting a capacitance between the detecting unit and an object to be detected, a resonating circuit including a second ceramic resonator and having a resonance point which varies with the small change in capacitance detected by the detecting unit, a high impedance circuit connected between the oscillator and the resonating circuit, and a high impedance circuit connected between the resonating circuit and the detecting circuit.

Abstract: Apparatus for detecting thickness which includes an electrode detecting unit including a ground electrode and a detecting electrode. The electrodes oppose each other along a paper path. An oscillating circuit provides an oscillation frequency signal. A resonant circuit, having a resonator independent of the oscillating circuit, has a resonance point which changes in accordance with a change in electro-static capacitance corresponding to a change in paper thickness detected by the electrode detecting unit. A resonant circuit outputs a detection signal corresponding to the change in resonance point. By analyzing this detecting signal, a state of two sheets of paper passing through the path is detected as a change in paper thickness.

Abstract: A method and apparatus for the non-destructive testing of a protective baer material. In a preferred embodiment, the method comprises applying an alternating electrical current across the protective barrier material for establishing a conductivity, G, of the protective barrier material and/or a quality factor, Q, of the protective barrier material. The conductivity, G, and/or the quality factor, Q, are measured at more than one frequency. The quality factor and/or conductivity measurements so obtained at the more than one frequency are compared to predetermined quality factor and/or conductivity limits.

Abstract: A dielectric constant measurement probe assembly includes a coaxial cable ving a outer electrical conductor and a center electrical conductor extending within the outer conductor and terminating at an end portion which projects beyond an end portion of the outer conductor. An adapter member has a central passage receiving the coaxial cable with the outer conductor of the cable extending through the passage of the adapter member and projecting therefrom. An outer tube has a bore composed of first and second axial sections. The second bore section is smaller in diameter than the first bore section. The adapter member is inserted in the first bore section with the end portion of the coaxial cable outer conductor inserted into the second bore section and making electrical contact therewith such that the outer tube thus constitutes an extension of the outer conductor.

Abstract: The electrostatic capacitance sensing circuit comprises a resonance circuit composed of an electrode capacitance formed by a substance to be measured and sandwiched between two opposing electrode plates and an inductance at least part of which is connected in parallel to the electrode capacitance; an active element (e.g. transistor) for constituting an oscillator in cooperation with the resonance circuit; and in particular a capacitor connected between the resonance circuit and the active element. Since a dc bias voltage of the active element is substantially not applied to the electrode plates, it is possible to prevent electrolytic corrosion of the electrode plates due to electromotive force generated between the electrode plates when ions are resolved into the substance to be measured and therefore the substance changes to an electrolytic solution.