This report describes a novel technique for the calibration of accelerometers. The theory is based on acceleration as a vector quantity and the fact that the mathematical function of accelerometers is the projection of a real motion vector space to a signal vector space. The sensitivity should be therefore be defined as a matrix. The definition of the calibration shall be to derive all of the components in the sensitivity matrix. The transverse sensitivity value in the conventional definition can be derived using sensitivities in the sensitivity matrix. Cross sensitivity makes a large influence on the measurement error.

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Plant has the capability to remediate the earth environment. Especially, it has high purification capability for air-pollution. In this paper, the capabilities of golden pothos and peace lily were examined. The subjects were planted in a plant pot. In the experiment, these subjects were installed in an experimental chamber of 300 liters respectively and the purification characteristics were monitored by a tin oxide gas sensor. The responding characteristic of the sensor, which means a plant purification capability, keeps the first order system which is used in the automatic control. Therefore, the time constant is employed to evaluate the plant capability. The capabilities of golden pothos and peace lily for formaldehyde, toluene and xylene were nearly constant even if the concentrations were changed. The capability of golden pothos for formaldehyde was 1.5 times higher than the one of peace lily. The capability of peace lily for toluene was 1.2 times as high as the one of golden pothos. The capabilities of golden pothos and peace lily for xylene were almost equal. It was also understood that the purification capability became lower as the molecular weight of the pollutant was larger. Plants were also set in a real environment. Total Volatile Organic Compounds (TVOC) and odors were measured to examine purification effect of plants. As for the results, removal rate for TVOC was 74% and the one for odor was 68%. It was confirmed that plants also had high purification capability in the real environment.

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We have developed a thermal anemometer with novel structures of micro-air-bridge heater and micro wind tunnel to regulate flow direction, which is fabricated by silicon micromachining technique. The features of sensor are low electrical power consumption and quick response. By using the sensor head with inclined package to flow direction, we have significantly improved the characteristics of the anemometer with a wind velocity up to 30m/s and a directionality of ±15 degree within an accuracy of 0.7%.

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The objective of this study is qualitative and quantitative analysis of chemical species reacting to surface of semiconductor sensors. In ordinal studies on detection of gas species by semiconductor sensors, researchers attach importance to the chemical sensitivity of sensors and notice the output value of sensors in the stationary state of the response characteristics. However, the response in the transient state, i.e., the region between the beginning of reaction and the equilibrium of reaction, has much information of chemical processes of gases reacting to surface of sensor. Hence, in this study, we adopt an autoregressive (AR) model in which the parameters describing exponential curves are looked for. As a procedure, we construct a model of reaction on the surface of sensor and assume it as the first order reaction in gas molecule. We simulate the chemical processes mathematically, and apply the AR model on the signal. Then, we reproduce the reaction rate constants and the initial amplitudes and identify the species of gases.

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This paper presents an acoustic amplifier working in an equivalent way to field effect transistors (FETs). The acoustic amplifier allows compensation in sound gain loss. The sound is generally transferred electrically and amplified by electrical circuits. Our key idea is to apply the pressure-controlled fluidic device for the acoustic amplifier. MEMS technology can provide a compact acoustic amplifier so as to be integrated in functional acoustic systems with other acoustic components. This paper reports working principle and characteristics of the developed acoustic amplifier.

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In this paper, sensor response by metal electrode and electrode surface condition was described. Single detecting film and multi metal electrodes were also examined. Metal electrode was changed from the conventional Ag and Au plate to Au, Ti and Cr evaporated metal films. To detect five basic taste substances, sensor parameters were defined by maximum voltage change and response time. Using these parameters five basic substances were clearly discriminated.

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