The computer for scuba diving is necessary equipment for safety dive. And it computes inhalation or discharge of the nitrogen by the experence learning which causes decompression sickness.Usual dive computer is big, so people we ars it only when people dive. However, weachieved "wearable computer" which provides the safety function, by using saving technology of watch. The deveropment makes it small, makes it possible to carry always and takes in the information of individual. I describe about outline of watch size computer for scuba diving, which we developed for the first time in the world, in this paper.

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A reliable quadric formula for frequency turn-over temperatures versus electrode film thicknesses in quarts crystal tuning forks was proposed and the coefficients were determined by the least squares method using the experimental results of 32-kHz and 76-kHz tuning forks. And a new analysis for the Young's modulus of the electrode film was also proposed using a bar flexural vibration frequency equation. It was found that the mass loading theory could not explain the frequency turn-over temperature characteristics versus electrode film thicknesses for quartz crystal tuning forks, while this theory could well explain the experimental results of tuning forks.

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Relative vertical motions between two planes produce load carrying capacity, called squeeze effect. Compressive squeeze air films generated by oscillation of piezoelectric actuators suspend the rotating shaft. Because it requires no air supply, squeeze bearings are applicable to special situation where any air flows in/out have to be avoided. In this study, the active squeeze bearing is proposed, which corrects the motion errors of rotating shaft application of controllable piezo-driving patterns allows the shaft manipulation. In this paper, the air film characteristics are investigated experimentally for a prototype model with two circular plates of 15mm in radius as oscillating pads. The squeeze air film was able to support the object against the external load of 4.9N with a mean film thickness of 5.5μm. It had the capability to support an external load up to 9.8N with a stiffness of 1.8N/μm. By constructing a simple feedback system, the object was manipulated accurately without contact.

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In order to realize a high-speed, accurate and compact positioning system by a parallel mechanism, it is necessary to use ball joints each having three degrees of freedom. Such a ball joint is requested to have highly precise spherical surface inside the housing, in which a shank-connected "sun ball" in center and "satellite balls" around it are all put away. In the present study, we focused our attention to obtain a genuine spherical surface inside the housing and to control the position of center of the sphere precisely. We examined various processes by using a self-made polishing machine for the exclusive use. Through those examinations we got good results, and here we report them besides with a measuring method of a spherical surface.

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The conventional concept of computing and network, that computers are operated by human, can change into the new concept of sensor-based pervasive computing and network, that computers and networks operated automatically without human operation. In this paper, we researched application fields of such new computer-network system, such as health care, environment monitoring, disaster privation and home amenity control, and values of new systems in future society.

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