Taste can be quantified using a multichannel taste sensor with lipid/polymer membranes. Its sensitivity and stability are superior to those of humans. A present study is concerned with the first step of miniaturization and integration of the taste sensor with lipid/polymer membranes using FET. As a result, it was found that gate-source voltage of the taste sensing FET showed the same behaviours as the conventional taste sensor utilizing the membrane-potential change due to five kinds of taste substances. Discrimination of foodstuffs was very easy. A thin lipid membrane formed using LB technique was also tried. These results will open doors to fabrication of a miniaturized, integrated taste sensing system.

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A motion of an electrostatic micromechanism with a cantilever movable electrode and a counter fixed electrode was studied theoretically by using the Rayleigh-Ritz method. As trial functions which express deformation states of the movable electrode approximately, deflection lines under applications of various uniform loads to the movable electrode were selected. In non-contact states of the movable electrode with the counter electrode, a hysteresis was confirmed in displacement (of the movable electrode)-applied voltage (between the both electrodes) curves of a voltage increasing and a voltage decreasing process. In contact states of the both electrodes, a hysteresis didn't appear in contact area-voltage curves and a threshold voltage above which a contact area increases rapidly with an increase of the applied voltage was derived. The threshold voltage, which determines an operation voltage of the mechanism, was almost proportional to L^-2, T^3/2 and d₀ (L, T: the length and the thickness of the movable electrode, respectedly, d₀: the gap width between the movable and the counter electrode).

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Methods of designing a radial-basis-function-network-based (RBFN) controller and implementing it for controlling a piezopolymer bimorph flexible micro-actuator are presented. By focusing on the sigmoid function, which is generally used as the neuron activation function of neural networks and whose derivative shape is similar to that of a Gaussian function, we derive an RBFN controller by applying a differential operator to an NN controller. Applications in which a flexible micro-actuator is controlled by the RBFN controller are also described. Simulations show that the proposed controller is effective at controlling a flexible micro-actuator.

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A tooth-movement transducer using bender-type piezoelectric ceramics was developed for the measurement probe of the Tooth Mobility tester. It is small, light and suitable for oral examination and it is possible to evaluate the tooth mobility of a molar in the direction of the tooth axis. The transducer utilizes a set of long and rectangular ceramic beam. It includes two supporting points and it is possible to adjust the resonance frequency by moving two points. This frequency is applied as the measuring frequency. The basic characteristics of the transducer and clinical applicability of the measurement probe are confirmed using an artificial tooth model and human tooth.

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Vibration-sensor made of an optical fiber with bulb-end (this also acts as a seismic mass) in V-groove on an Si substrate is proposed, and fundamental characteristics of this sensor are demonstrated. Nearly flat frequency dependence of the optical output was obtained in the frequency range between observed 40 and 1200Hz under the constant acceleration. Resolution (or equivalent noise level) of 0.3m/s² is attained in this prototype device. Vibrations with many modes in a vibrator are analyzed by FFT analysis of optical signals output from this vibration-sensor. Setting displacement of optical axes, about 30μm, between optical fiber with bulb-end (input fiber) and output fiber, and small amplitude of about 1μm of the input fiber lead to linear relationship between acceleration and optical output.

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The characteristics of (110) silicon anisotropic bulk etching are studied with varied temperature and concentration of aqueous KOH solution. The etch rates of (110) and (111) planes increase with increasing temperature but decrease with increasing concentration. The maximum etch rate ratio is above 150 at 45 exact wt.% and 60°C of aqueous KOH solution. Surface roughness varies greatly with concentration, and the minimum roughness is observed in an aqueous KOH solution of 41 exact wt.%. In 41 exact wt.% aqueous KOH solution at 65°C, comb structure have been fabricated which are 8μm wide, 150μm high and separated by 7μm gaps, using a comb mask pattern 10μm wide with 5μm gaps.

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We have used the integrated SQUID gradiometer in an unshielded environment to make eddy current nondestructive testing measurement on a multi-layer aluminum structure. The sensor consists of a niobium dc superconducting quantum interference device (SQUID) and a first-order gradiometer pick up coil on the same substrate. As a demonstration of their capabilities, subsurface defects in a multilayer aluminum structure have been located and mapped using eddy current with no magnetic shielding around the specimen or cryostat.

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The new application of piezoelectric quartz-crystal microbalance (QCM) sensors to fire detection is described. The QCM sensors are coated with plasma organic films which are sensitive to vapors emitted from burning polyvinyl chloride (PVC) cables and epoxy resin circuit boards. These vapors must be distinguished because these sensors also respond to humidity. Principal component analysis reveals that this system can discriminate between vapors emitted from burning materials and humidity. Vapor discrimination is also described using the Kohonen's Learning Vector Quantization (LVQ).

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This paper presents an eddy-current sensor with a novel contactless structure to determine the very low concentration of electrolytic solution. By detecting the change in inductance of the sensing coil due to formation of eddy-current inside the conducting solution it is possible to determine the very low concentration of electrolyte solution. Concentration as low as 1 ppm for strong electrolyte is possible to measure. It was tested for various concentrations of NaCl. It shows distinct response for each concentration.

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