Hiroaki Ushirosako's research while affiliated with The University of Tokyo and other places

This paper describes a power supply tap which can acquire power consumption history and control the power supply of home appliances plugged into it. Besides it has shape and apperance that user can put on accessible place (e.g. a television rack). It can be utilized for a power monitoring and controlling system. The system realizes comfortable, safety and energy saving condition by on-off contorlling of ready-made home appliances. In this paper, development of a prototype of the tap (iTap) is introduced, and as some typical application examples of the iTap, following three services are described to automatic on-off control of ready-made home appliance. (1) Classification of home appliances whether on-off control is acceptable, (2) automatic on-off control by association analysis and (3) automatic off control by detection of abnormal power consumption via clustering.

This paper describes a novel wireless sensor network system that provides both functions of sensor value transmission and sensor localization. ZigBee technology is utilized as wireless network protocol in our system because of its advantages in terms of power consumption and easiness of self-organizing mesh network. For location estimation, Received Signal Strength Indicator (RSSI) is leveraged and a robust grid based sensor localization algorithm is proposed. A testbed location aware ZigBee-based system is successfully evaluated in terms of its performance of sensor value transmission and sensor localization functions.