1. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, Urbana, IL 61801 (corresponding author).
2. Professor, Dept. of Civil and Environmental Engineering, The Hong Kong Univ. of Science and Technology, Room 3569, Clear Water Bay, Kowloon, Hong Kong.
3. Research Assistant Professor, V.T. Chow Hydrosystems Lab., Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, Urbana, IL 61801.
4. Chester and Helen Siess Professor and Director, V.T. Chow Hydrosystems Lab., Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, Urbana, IL 61801.