Hayato Yamaguchi Hiroshi Nakajima Kazuhiko Taniguchi Syoji Kobashi Katsuya Kondo Yutaka Hata Fuzzy Detection System of Behavior before Getting Out of Bed by Air Pressure and Ultrasonic Sensors. 114-119 2007 conf/grc/2007 GrC http://doi.ieeecomputersociety.org/10.1109/GRC.2007.66 db/conf/grc/grc2007.html#YamaguchiNTKKH07