1. Department of Intelligent Automation Engineering, Chung Chou University of Science and Technology, Yuanlin City 510, Changhua, Taiwan, R.O.C.
2. Department of Mechanical Engineering, Tatung University, Taipei City 104, Taiwan, R.O.C.
3. Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu City 300, Taiwan, R.O.C.