1. Professor, Dept. of Civil Engineering and Hydrotech Research Institute, National Taiwan Univ., Taipei 10617, Taiwan (corresponding author). E-mail: kuoj@ntu.edu.tw
2. Late Professor, Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, Urbana, IL 61801.
3. Ph.D. Candidate, Dept. of Civil Engineering, National Taiwan Univ., Taipei 10617, Taiwan E-mail: ychsu1978@gmail.com
4. Engineer, Water Resources Agency, Ministry of Economic Affairs, formerly, Graduate Student, Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, Urbana, IL 61801.