1. Assistant Professor, Dept. of Information Management, Toko Univ., Chai-Yi, 603, Taiwan, Republic of China.
2. Professor, Dept. of Harbor and River Engineering, National Taiwan Ocean Univ., Keelung 20224, Taiwan, Republic of China (corresponding author).
3. Graduate Student, Dept. of Harbor and River Engineering, National Taiwan Ocean Univ., Keelung 20224, Taiwan, Republic of China.