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A capacitive pressure sensor for measuring a pressure applied to an elastic member includes a capacitive plate disposed adjacent to the elastic member so as to define a gap between a planar conductive surface of the elastic member and a corresponding planar surface of the capacitive plate. The gap,

A capacitive pressure sensor for measuring a pressure applied to an elastic member includes a capacitive plate disposed adjacent to the elastic member so as to define a gap between a planar conductive surface of the elastic member and a corresponding planar surface of the capacitive plate. The gap, capacitive plate and elastic member together define a capacitor having a characteristic capacitance. The sensor further includes an elongated electrical conductor characterized by an associated inductance value. The conductor is fixedly attached to and electrically coupled with the capacitive plate. The gap between the capacitive plate and the elastic member varies as a predetermined function of the pressure applied to the elastic member so as to vary the characteristic capacitance. The capacitor and the electrical conductor together form an electrical resonator having a characteristic resonant frequency. Varying the capacitance of this tank circuit varies the resonant frequency of the tank circuit. Thus, the resonant frequency of the tank circuit is indicative of the pressure applied to the elastic member. The close physical proximity of the capacitor and the electrical conductor equalizes the effects of environmental influences such as temperature variations, vibration and shock, thus making such effects more predictable.

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A capacitive pressure sensor for measuring a pressure applied to an elastic member includes a capacitive plate disposed adjacent to the elastic member so as to define a gap between a planar conductive surface of the elastic member and a corresponding planar surface of the capacitive plate. The gap,

A capacitive pressure sensor for measuring a pressure applied to an elastic member includes a capacitive plate disposed adjacent to the elastic member so as to define a gap between a planar conductive surface of the elastic member and a corresponding planar surface of the capacitive plate. The gap, capacitive plate and elastic member together define a capacitor having a characteristic capacitance. The sensor further includes an elongated electrical conductor characterized by an associated inductance value. The conductor is fixedly attached to and electrically coupled with the capacitive plate. The gap between the capacitive plate and the elastic member varies as a predetermined function of the pressure applied to the elastic member so as to vary the characteristic capacitance. The capacitor and the electrical conductor together form an electrical resonator having a characteristic resonant frequency. Varying the capacitance of this tank circuit varies the resonant frequency of the tank circuit. Thus, the resonant frequency of the tank circuit is indicative of the pressure applied to the elastic member. The close physical proximity of the capacitor and the electrical conductor equalizes the effects of environmental influences such as temperature variations, vibration and shock, thus making such effects more predictable. g multiphase flow within said flow pipe; means for measuring actual phase fractions of said multiphase flow within said flow pipe, said means for measuring actual phase fractions being located down stream of an adjacent to said means for conditioning multiphase flow; and data acquisition and processing means in communication with said cross correlation type flow meter and said means for measuring actual phase fractions for collecting data therefrom and carrying out calculations for flow rates of individual phases of said gas/liquid multiphase flow. 2. The apparatus of claim 1 further comprising a throttle type flow meter located downstream of said means for conditioning multiphase flow and adjacent to said means for measuring actual phase fractions. 3. The apparatus of claim 1 further comprising a device for measuring temperature and a device for measuring pressure separately mounted on said flow pipe. 4. The apparatus of claim 3 wherein said means for conditioning multiphase flow is a static multiphase flow diverter. 5. The apparatus of claim 4 wherein said static multiphase flow diverter comprises a buffer and a bypass; said buffer having an inlet, an outlet, and bypass-outlet, said outlet being located at a lower position than said inlet and said bypass-outlet; said inlet and said outlet of said buffer being connected to said flow pipe; one end of said bypass being connected to said bypass-outlet of said buffer while the other end of said bypass is connected to said flow pipe at a position downstream of said means for measuring actual of phase fractions. 6. The apparatus of claim 5 wherein a diameter of said buffer of said static multiphase flow diverter is larger than either that of said flow pipe or that of said bypass of said static multiphase flow diverter. 7. The apparatus of claim 1 wherein said static means for generating slug flow comprises at least one blind tee. 8. The apparatus of claim 7 wherein said at least one blind tee consists of a tee tube and a blind flange; said tee tube having a inlet, a outlet, and a blind-let; said blind flange being fixed on said blind-let. 9. The apparatus of claim 1 wherein said static means for generating slug flow comprises at least one inverted U pipe. 10. The apparatus of claim 1 wherein said static means for generating slug flow comprises an at least one folding pipe section. 11. The apparatus of claim 1 said means for conditioning multiphase flow is a static mixing device. 12. The apparatus of claim 1 wherein said means for conditioning multiphase flow is a static multiphase flow diverter. 13. The apparatus of claim 12 wherein said static multiphase flow diverter comprises a buffer and a bypass; said buffer having an inlet an outlet, and a bypass-outlet, said outlet being located at a lower position than said inlet and said bypass-outlet; said inlet and said outlet of said buffer being connected to said flow pipe; one end of said bypass being connected to said bypass-outlet of said buffer while the other end of said bypass is connected to said flow pipe at a position downstream of said means for measuring phase fractions. 14. The apparatus of claim 13 wherein a diameter of said buffer of said static multiphase flow diverter is larger than either that of said flow pipe or that of said bypass of said static multiphase flow diverter. 15. The apparatus of claim 1 wherein said apparatus does not include a moving component. 16. The apparatus of claim 1 wherein said means for measuring actual phase fractions and said means for conditioning multiphase flow are located downstream of said cross correlation type flow meter in said flow direction. 17. The apparatus of claim 1 wherein said means for measuring actual phase fractions and said means for conditioning multiphase flow are located upstream of said cross correlation type flow meter in said flow direction. of a ultrasonic propagating element in the form of wedge having a bottom surface and a slanting surface extending from one edge of the bottom surface at an acute angle, and a ultrasonic transducer attached on the slanting surface. The ultrasonic propagating element is composed of a plurality of sheet units in which each sheet unit is composed of plural high modulus fibers aligned in parallel in resinous material, whereby propagating ultrasonic wave emitted by the ultrasonic transducer onto the bottom surface at an angle perpendicular to the slanting surface.