1. Department
of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
2. Department
of Mechanical and Automation Engineering, Chinese University of Hong Kong, Shatin, Hong Kong
3. Department
of Mechanical Engineering, Sejong University, Seoul 143-747, Republic of Korea
4. Department
of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States