1. Associate Professor, Dept. of Hydraulic and Ocean Engineering, National Cheng Kung Univ., Tainan 701, Taiwan (corresponding author).
2. Ph.D. Candidate, Dept. of Hydraulic and Ocean Engineering, National Cheng Kung Univ., Tainan 701, Taiwan.
3. Professor, Dept. of Hydraulic and Ocean Engineering, National Cheng Kung Univ., Tainan 701, Taiwan.