1. Department of Mechanical Systems EngineeringFaculty of EngineeringKogakuin University2665‐1 Nakano‐machi, HachiojishiTokyo192‐0015Japan
2. Addictive Substance ProjectTokyo Metropolitan Institute of Medical Science2‐1‐6 Kamikitazawa, Setagaya‐kuTokyo156‐8506Japan