1. Department of Vehicle Engineering, National Taipei University of Technology No. 1, Section 3, Chung-Hsiao East Rd, Taipei, Taiwan 106, Department of Mechanical Engineering, National Taiwan Univ. of Science and Technology, No. 43, Keelung Road, Section 4, Taipei, Taiwan 106,
2. Department of Mechanical Engineering, National Taiwan Univ. of Science and Technology, No. 43, Keelung Road, Section 4, Taipei, Taiwan 106