1. Professor, Dept. of Power Mechanical Engineering, National Tsing Hua Univ., 101 SEC 2 Kuang Fu Road, Hsinchu, Taiwan 30013, R.O.C. (corresponding author). E-mail: hwchiang@pme.nthu.edu.tw
2. Graduate Student, Dept. of Power Mechanical Engineering, National Tsing Hua Univ., Hsinchu, Taiwan 30013, R.O.C. E-mail: ericwang5207@yahoo.com.tw
3. Professor, Dept. of Mechanical Engineering, Chung Hua Univ., Hsinchu, Taiwan 300, R.O.C. E-mail: bjtsai@chu.edu.tw