Gaseous indoor air-pollutants are detected by a tin oxide gas-sensor using the OPS5 system. The system is one of several production systems. The grade of pollution can be indicated more correctly by recognizing types of human behaviors, awaking and sleeping etc. The standard level for gaseous indoor air-pollution is computed by sensor outout data in last 3 weeks. The current input data is compared with the level and the grade of pollution displayed. There are 15 rules to help recognizing indooor air-pollution. Rete algorithm is adopted to match working memory elements and condition parts of rules in production memory quickly.

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In this paper, a new multi-functional sensing technique for discrimination of surface roughness and temperature on material surface model using a pressure-conductive rubber sheet tactile sensor is described. This technique is aiming to realize an artificial device with sensing ability of the human skin as a final goal.
We recognized that the resistance of pressure-conductive rubber sheet generally used as two-dimensional pressure sensing device was influenced not only by pressure but also by temperature. For discriminating both the material surface model and the temperature, the trial tactile sensor consisted of eight latticed small patch elements with two kinds of pressure-conductive ruber sheet is developed. This tactile sensor has two outputs because two output signals of sensor are needed to obtain the information about two unknown quantities, a kind of material surface model and temperature.
The experimental results which were the surface characteristics in accordance with surface model with constant touch force (2kgf) and constant temperature (25°C), and the temperature characteristics on three kinds of surface models in constant touch force (2kgf), showed the possibility of proposed multi-functional sensing technique for the surface model and the temperature of material.

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A quartz resonator with its electrode coated with sensing film is used as gas sensor and its output is resonance frequency shift due to mass loading effect. It is possible to measure frequency shift by impedance analyzer. However, the method to measure the shift using oscillation circuit is more often used for simplicity. The oscillation frequency shift deviates from that of resonance frequency due to dependency of active impedance upon its load change when viscoelastic effect accompanied with film coating of vapor sorption occurs. Then we established analysis method of oscillation frequency shift, taking dependency of active impedance upon change of load into account. Furthermore, we determined the condition of load parameters within which oscillation frequency shift agrees with resonance frequency one.

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The metal oxide devices such as a thermistor and a varistor in the form of bulk or thick film which are applied for instruments, control and electronic circuits, have been developed. However, preparation of metal oxide thin film is difficult because of a high melting point of oxide material and irregular components including impurities. To solve this problem, the authors perceived that a low melting point metal becomes a metal oxide with a high melting point by oxidation, then devised the new method which after deposited according to order of Mn and Fe powder with high melting point from Zn with low melting point in vacuum, its multilayered metal can be converted into a metal oxide via profile of high temperature annealing in air. Through this process, the metal film with low melting point than annealing temperature does not disperse, so that a composite metal oxide semiconductor thin-film (COT) with thickness of 0.7-1.5μm is prepared. A markedly temperature dependent COT is suitable for a high sensitive microsensor responding to minute temperature change. The paper describes preparation of COT and construction of an enzyme sensor system based on chemical reaction heat for detecting nitrogen metabolite such as urea.

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This paper presents a novel multi-functional tactile sensor. It has a mono-structure, but has three kinds of sensing functions for discriminating material properties and a touch force sensing function which is a basic function in a tactile sensor. The proposed sensor is used to discriminate typical materials such as iron, aluminium, copper, brass, rubber, acrylic resin, styrene foam and so on.
The sensor consists of two comb shaped metallic lines on both faces of a thin insulated substrate with eight terminals. From different combinations of these terminals, the four sensing functions discribed above can be realized.
The experiments show good results to discriminate each sample of materials. The proposed sensor is expected to serve as a step toward the development of an artificial skin tactile sensing system in the future.

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We have developed an infrared light source made of a heavily doped single crystal silicon microbridge. This microbridge was formed by boron ion implantation and ammonia anisotropic etching. This infrared light source comprises a microheater. Accordingly infrared light is radiated from the heated microbridge. Because the ion implantation is possible to form a very thin layer of heavily doped single crystal silicon, the microheater has very small heat capacity. The size of the microheater is about 650×200×1.5μm³. It had a peak of radiant intensity at 4μm wavelength. Only 150mW drive power was consumed to raise the temperature of the microheater to 780°C. It had a small thermal time constant less than lmsec, and wide modulated temperature more than 700°C at 100Hz. Therefore, the infrared light source can radiate intermittent infrared light with direct electrical power drive. There is possibility that handy infrared sensing systems are realized.

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