The purpose of this study was to investigate the optimum farming conditions for mushrooms from the view point of engineering field. As the bio-electric potential of mushrooms is considered to be closely related to the activation of mushroom cells, this relationship has been used to analyze the dependence of the morphogenetic characteristics of Grifola frondosa on farming temperatures (from 16 to 22 degree C). The experimental results indicated that a maximum response was exhibited, with correspondingly favorable morphogenesis obtained at 18 degree C. Based on the experimental results, including those in a previous study, it was assumed that the larger the bio-electric potential becomes, the higher the growth yield reaches. In order to support this assumption, growth promotion was conducted by intentionally activating the bio-electric potential within the mushrooms by stimulating them with short bursts of illumination. The resulting observation of growth promotion permitted the conclusion that the bio-electric potential can, indeed, be regarded as an index of growth.

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This paper presents to sense the functional information of a bone with the visualization of wave propagation in the bone tabescular structure. Firstly, a cross sectional image of a bone was acquired with a X-ray CT (computed tomography). Secondly, image processing techniques were applied the image to reveal the tabescular structure; binarization procedure for tabescular detecting, labelling procedure for noise reduction and skeltonized procedure for tabescular structure. Thirdly, the wave propagation was visualized in the tabescular structure. The experimental results demonstrate the impulse response of an acoustic wave through the tabescular structure.

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Magnetic field measuring equipment provides us the way to examine the active position of a peripheral nerve without contact or invasion. To develop a process to estimate the position precisely, simulation study of the magnetic field induced by a myelinated nerve fiber was executed. The electric current sources around the active position of a nerve fiber can be approximated as a pair of electric current dipoles, which represent depolarization and repolarization respectively. Therefore the current sources to estimate from the detected pattern of the magnetic field were modeled as a pair of electric current dipoles. A repetitive adjustment process was proposed as an effective method to find the appropriate positions of the dipoles as the sources of the magnetic fields.

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This research focuses on developing visual assistance for ultrasound echographic measurement. Proposed system performs a direct projection of the intersectional imagery onto the patient's body by an optical projector. The surface shape of the patient is taken into consideration for image projection. Optical shape measurement and graphical synthesis techniques are combined for producing distortion-free images so that the physician can intuitively manipulate the ultrasonic probe and observe the echography in the identical physical space.

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A tantalum-nitride thin-film resistor with a low-variability resistance was formed by optimizing the conditions for depositing a tantalum-nitride thin film. The thin film was deposited by RF-magnetron-reactive sputtering, and nitrogen-pressure ratio, substrate temperature, and deposition rate in the conditions were optimized by measuring electrical properties of the deposited film. Based on the measured resistivity and temperature coefficient of resistance, a nitrogen-pressure ratio of 6.0%, a substrate temperature of 350°C, and a deposition rate of 50 nm/min were chosen as the optimum conditions suitable for mass production of the film. The resistor using the thin film deposited under the optimum conditions was fabricated on a silicon optical bench, and showed that its change in resistance is less than 1.4% after conducting reliability tests, which consist of a high-temperature test, a damp-heat test, and a heat-cycle test. Furthermore, the reliability tests estimated that the change in resistance of the resistor would reach only 2.0% even if the 10⁴-hour high-temperature test, which is the severest in three tests, is carried out. It is thus concluded from these results that fabrication under the optimized conditions can produce a thin-film resistor with a low-variability resistance.

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Bucket Brigade Device (BBD) adding-delay architecture was proposed as the analog beamformer for piezoelectric micromachined ultrasonic sensor phased array. BBD adding-delay architecture were used both as delay and adding elements, and the input signals were distributed adding in the process of delay. This architecture was useful to reduce chip area, simplify system design, and realize on-chip integration. Combining piezoelectric micromachined ultrasonic array sensors and the analog delay-sum circuits successfully performed two-dimensional object detection.

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A Microfocus X-ray inspection apparatus requires a grid mask as a scale which gives an indication of distortion correction and magnification. In addition, a grid mask must be an X-ray absorber. A thick micro structure is available to an X-ray absorber. Ni which is a typical electroforming material has a vocation for a thick micro structure. In this study, we make use of Ni micro structure 40μm thick as X-ray absorber. We fabricated the Ni grid mask using LIGA-like process. When the X-ray tube voltage was 70kV, we could observe the plain gird through an IC chip. Additionally, the center distance of the grid was to within an average of ±1μm in both the lengthwise direction and crosswise direction. These results suggest a Ni micro-structure is available as the position indicator for a Microfocus X - ray Inspection Systems.

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In this paper, we propose the new method for concentration discrimination of alcohol using the ultrasonic sensor. The detection method adopts the difference in each temperature characteristic of propagation time of an ultrasonic wave for various kinds of concentration in ethanol solution. First we checked the temperature characteristic of the propagation time in each concentration of ethanol solution and obtained interested experimental results. Secondly we applied for the alcohol concentration discrimination in several liquors and found good experimental results. From the experiment results, we could point out the possibility of the alcoholic concentration discrimination by the proposed method.

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