1. Ph.D. candidate, College of Water Conservancy & Hydropower Engineering, Hohai Univ., 1 Xikang Rd., Nanjing, China 210098 (corresponding author).
2. Professor, College of Water Conservancy & Hydropower Engineering, Hohai Univ., 1 Xikang Rd., Nanjing, China 210098.
3. Professor, Dept. of Civil Engineering, Univ. of Toronto, 35 St. George St., Toronto, ON, Canada M5S 1A4.
4. R&D Associate, Oak Ridge National Laboratory, 1 Bethel Valley Rd., P.O. Box 2008, Oak Ridge, TN 37831-6038.