In order to realize a low-cost and power-saving positioning system using PHS, an algorithm to judge moving and stopping status of distribution equipment from continuous vibration measurement is developed. The key for this algorithm is a decision of threshold level, which differs according to the distribution equipments. For this, we developed the studying algorithm, which uses the result of PHS location measurement as a training data. It gets position data measured by PHS one or two times a day, measures acceleration-level continuously, updates maximum and minimum acceleration-level in a day when the equipment is moving or stops, and sets the threshold of acceleration level. This algorithm is implemented onto the device and attached it to the safety package for valuables. The fundamental availability of this algorithm is confirmed through the experiments.

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In this paper, we investigated transmission characteristics of intra-body transmission system in frequency range from 300kHz to 1GHz. The transmission efficiency through the human body was 20dB or more than that through the air at all frequency less than 55MHz. We adopted Orthogonal Frequency-Division Multiplexing modulation for speeding up of the intra-body transmission throughput and investigated the effects of speeding up by wider bandwidth. When a human was holding electrodes of transmitter and receiver with left and right hand, the throughput was 21.3Mbps, and 40.3Mbps between hand and wrist. Stable transmission of high-definition video and audio signal using OFDM through the human body has been demonstrated without transmission delay.

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In this study, a diamond end effector used to grasp minute objects is manufactured. The end effector has an elastic hinge mechanism and is driven using a shape memory alloy (SMA) sheet. However, the end effector is approximately square with side 2-3mm, which is inappropriate for stress measurement. Also, diamond is a brittle material; thus, it is difficult to predict the behavior of the end effector. Therefore, we carried out a simulation of stress concentration with respect to the displacement of the end effector by finite element analysis using linear programming to optimize the design of the end effector. As a result, we succeeded in reducing the use of diamond by approximately 21.4% (volume) without significantly changing the maximum stress. It was confirmed that our design method is effective for the design of end effectors made of diamond.

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The Citizen group has succeeded in developing a catalytic-combustion-type hydrogen sensor leveraging on microfabrication and new material technologies, both developed in the production of timepieces. The new product is the world's first carbon monoxide sensor having a coiled coil (double helix) structure. In the heat coils of conventional gas sensors, a single spring structure is used. Citizen has adopted a coiled coil construction in which a double-helix spring structure is employed for the heat coil.

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