Abstract: A MEMS microphone includes a diaphragm having conductivity, first and second variable capacitors respectively including first and second fixed electrodes, a first voltage output section that outputs a first voltage changed according to a change in a capacitance of the first variable capacitor, and a second voltage output section that outputs a second voltage changed according to a change in a capacitance of the second variable capacitor. The first and second fixed electrodes face the diaphragm. The capacitances of the first and second variable capacitors are changed in accordance with a vibration of the diaphragm. A first bias voltage is applied to the first fixed electrode. A reference voltage is applied to the second fixed electrode. A second bias voltage is applied to the diaphragm. A difference between the second bias voltage and the reference voltage is half of a difference between the first bias voltage and the reference voltage.

Abstract: A first heat generator heats a mixture of fluids to a first temperature. A predetermined thermal property value of the mixture set to the first temperature is obtained, the first heat generator heats the mixture to a second temperature, the thermal property value of the mixture set to the second temperature is obtained. First relationship information between the thermal property value of the mixture set to the first temperature and a mixture ratio of a first fluid is obtained. Second relationship information between the thermal property value of the mixture set to the second temperature and the mixture ratio of the first fluid is obtained. Mixture ratios are calculated based on the thermal property value of the mixture set to the first temperature, the thermal property value of the mixture of fluids set to the second temperature, the first relationship information, and the second relationship information.

Abstract: It is possible to reduce a decrease in accuracy of measuring the concentration of a measurement target gas even in a case where, in a mixture of gases, there is a gas greatly different from another gas in a rate of change in thermal conductivity with respect to temperature. The concentration measurement device includes a sensor configured to measure the concentration of a measurement target gas in a mixture of gases on the basis of thermal conductivity of the measurement target gas, the mixture of gases including two or more components, and a heating unit configured to heat the mixture of gases so that the concentration of the measurement target gas can be uniquely determined with respect to the thermal conductivity.

Abstract: A first heat generator heats a mixture of fluids to a first temperature. A predetermined thermal property value of the mixture set to the first temperature is obtained, the first heat generator heats the mixture to a second temperature, the thermal property value of the mixture set to the second temperature is obtained. First relationship information between the thermal property value of the mixture set to the first temperature and a mixture ratio of a first fluid is obtained. Second relationship information between the thermal property value of the mixture set to the second temperature and the mixture ratio of the first fluid is obtained. Mixture ratios are calculated based on the thermal property value of the mixture set to the first temperature, the thermal property value of the mixture of fluids set to the second temperature, the first relationship information, and the second relationship information.

Abstract: A cavity is provided in a substrate so as to penetrate from a front surface to a back surface of the substrate. A thin-film diaphragm for sensing acoustic vibrations above the substrate is provided over the cavity. At least one wall surface of the cavity is configured of a first inclined surface between the front surface of the substrate and a middle portion in the thickness direction, the first inclined surface gradually widening toward the outside of the substrate as the first inclined surface goes from the front surface of the substrate toward the middle portion, and a second inclined surface between the middle portion and the back surface of the substrate, the second inclined surface gradually narrowing toward the inside of the substrate as the second inclined surface goes from the middle portion toward the back surface of the substrate.

Abstract: A method and an apparatus for measuring an impurity concentration of a liquid comprises atomizing step for atomizing the objective liquid, e.g. pure water, having a predetermined droplet size distribution, and an evaporating step for evaporating to dryness the droplets so as to generate fine particles. Those particles are fed to a condensation nuclei counter, hereinafter referred to as CNC, which counts the number of fine particles and has a specified sensitivity characteristic curve. Then impurity concentration of the objective liquid can be measured, since the concentration is related to the counted number of the CNC, the distribution of droplet size of the atomizer, and the sensitivity characteristic of the CNC including the particle deposition loss.