Focusing on the PHS positioning service used in physical distribution of logistics, a positioning error offset method for improving positioning accuracy is proposed. The PHS system has a defect that the measurement errors are large ranging from several ten meters to several hundred meters caused by the fluctuation of radio waves by buildings around the terminal. In this research, an error offset method is developed which learns patterns of positioning results (latitude and longitude) containing errors and the highest signal strength at major logistic points in advance, and matches them with the new data measured at actual distribution processes according to Mahalanobis distance. Then the matching resolution is reduced to 1/40 of the conventional error offset method.

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A Spring Drive is a highly accurate mainspring driven watch that uses the mainspring as a power source and an electronic regulator to control hand speed. The output torque of the mainspring is highest when the mainspring is fully wound and gradually decreases as the mainspring unwinds. A torque-return system that extends the power reserve by winding the mainspring using energy spent on an electromagnetic brake when torque is high has been developed and provided on the Cal. 7R08. This system extends the power reserve by seven hours, without changing the mainspring.

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We developed a manufacturing process utilizing UV-LIGA process to fabricate high-precision metal components for mechanical watches. Surface roughness of the components was reduced to one-half to one-fifth of that of the components fabricated by traditional machining process. Weight reduction was also attained. These improvements in dimensional accuracy and weight contributed to improvement of timing accuracy and durability.

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To recognize human behavior, foot pressure sensing shoes were developed, and an analysis for discriminating the user's actions from the foot pressure distribution was examined, considering the movements, walking, running, standing, sitting, going upstairs and downstairs, and cycling. These seven actions were discriminated with a high accuracy using feature quantities such as the average, standard deviation, maximum, and difference deviation extracted from the data of only three sensors by discriminant analysis. In addition, by canonical discriminant analysis, discriminant functions which classify the seven actions with an accuracy of 100% were derived by using feature quantities extracted from the data of five sensors or less.

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Seiko Epson has developed the Direct Drive Cal. 5D as a new model of Kinetic series; its uniqueness is to enhance an interrelated communication with a user and a watch. Its characteristics are as follows: 1) A switching wheel accelerating rotating speed which synchronizes both automatic power generation and the manual power generation, which is newly developed. 2) A permanent power reserve system that has a power generation display function and then displays the amount of generated electronic power by manual power generation means. 3) An electronic charging load system that enables this model to display more accurate duration of operating compared to conventional rough calculation means.

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A diver watch with "Radio-Controlled" and "Eco-Drive" technologies implemented has been developed by Citizen Watch Co., Ltd. on a commercial basis. We report on an antenna, a receiver system and a structure of the movement which provide sufficient water-tightness and sensitivity of the radio-wave, thereby meeting stringent JIS and ISO requirements.

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