作者单位:Proton Therapy Division, Shizuoka Cancer Center Research Institute, 1007, Shimonagakubo, Nagaizumi[1]Heavy Ion Medical Research Center, Gunma University, 3-39-22, Showa, Maebashi, Gunma 371-8511, Japan[2]Department of Electrical and Electronic Engineering, College of Industrial Technology, Nihon[3]