Low Distortion Linear Voltage-to-Current Convertor Consisting of Twin MOSFET's Current Sources and Current Sinks Pair. - Hajime Takakubo; Ryo Watabe; Kawori Takakubo (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2003)

A Method for Estimating the Force Applied on the Forearm Using PPG Sensors. - Ryo Watabe; Kazuya Murao (MoMM, 2024)