1. a Faculty of Human Sciences, University of East Asia , Shimonoseki, 751-8503, Japan
2. b Human Technology Research Institute, National Institute of Advanced Industrial Science and Technology , Tsukuba, 305-8504, Japan
3. c Seating Division, NHK Spring Co., Ltd. , Yokohama, 236-0004, Japan
4. d Component Engineering Development Division, Nissan Motor Co., Ltd. , Atsugi, 243-0123, Japan