Atomic scale mechanical processing of a layered crystal structure material, muscovite mica, was performed using an atomic force microscope (AFM). To realize high-density memory, the possibility of using tribo memory which is consistent with nanometer scale mechanical processing of multilayered crystal structure material was suggested, and the processing properties of muscovite mica were studied using the cubic boron nitride (cBN) coated tip of the AFM. (1)More precise processing can be performed using a cBN coated tip than Si tip. On the formation line and space, the interval pitch was minimized to 50nm using the cBN coated tip. (2)For a digital information memory, to realize multi valued memory at the same place, the dependence of processing properties on contact load and scanning cycles was evaluated. The depth of the processed grooves increased discretely with the load. The interface between K-SiO₄ and SiO₄-K was weakly bonded, therefore, removed depths of 0.7 and 1.0nm were predominant. (3)For an analog information memory, the dependence of processing properties on the sliding direction was evaluated, and then Chinese characters [_??__??__??_] and a famous comic actor feature were processed within areas of 300×750 and 500×500nm², respectively.

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A new type of detector pixel circuit operated in a dielectric bolometer mode for infrared image sensor has been developed. The circuit features that change in dielectric constant against temperature is detected through that in capacitance of ferroelectric thin film capacitor such as BST (Ba_1-xSr_xTiO₃). Our proposed circuit is a capacitor-capacitor serially connected circuit, where at least one capacitor is composed from a BST ferroelectric thin film. In PSPICE circuit simulations, it is found that when a relative capacitance change in the BST ferroelectric capacitor, which beginning value is 0.10nF, of the detector circuit is 1%, the output level is about 25mV. After evaluating the assembled above circuit on board with a BST thin film capacitor fabricated on a Si membrane structure, we confirmed that the relationship between the output voltage level and capacitance change in the BST thin film in the assembled circuit agrees well with that in the corresponded simulation results.

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Taste can be measured using a taste sensor, which shows different electrical potential patterns for each food. The sensor has eight kinds of lipid membranes. The present study is concerned with the long-term measurements of milk and sensory analysis of milk. Each membrane was preserved in standard milk, and the tastes of five kinds of commercial milk were measured using the sensor preserved for a period of one month to six months in the same manner. It was found that calibrated data was comparable with data obtained other days, and that the membranes were used reliably fbr six months. On the other hand, richness of sensory test showed a high correlation with the ratio of milk fat using chemical analysis, as seen from the correlation coefficient 0.829. It was also found that there is significant difference among the four samples by performing a Kramer test (α<0.01) and F test (α<0.05). We used multiple regression analysis on sensor responses by use of the ratio of milk fat and the heat treatment of milk, and consequently found a high correlation between channel 4 and them. The correlation coefficient was-0.986 between the sensory test and ch. 4. Therefore, it was concluded that richness, which is the main taste of milk, can be quantified using the taste sensor.

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It is known that a plant and microorganisms inhabiting in the rhizosphere purifies an indoor air-pollutant. The empirical model, however, involves some problems such as the long interval time needed for the measuring of purification process, and the process is modeled by simple straight line approximation. In this study, we find the purification process of the plant in detail for the basic study of a design that suitably arranges plants in a room. As an example of typical foliage plant, purification process of Epipremnum aureum for formaldehyde is measured continuously using a gas sensor. As a result, it is found that the purification rate is fixed. Therefore, the purification process could be approximated using an exponential function.

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