1. Postdoctoral Scholar, Dept. of Civil and Environmental Engineering, Stanford Univ., Stanford, CA 94305.
2. Ph.D. Candidate, Dept. of Hydraulic and Environmental Engineering, Norwegian Univ. of Science and Technology, NO-7491 Trondheim, Norway.
3. Postdoctoral Associate, Saint Anthony Falls Laboratory and Dept. of Civil, Environmental, and Geo-Engineering, Univ. of Minnesota, Minneapolis, MN 55455.
4. Professor, Saint Anthony Falls Laboratory and Dept. of Civil, Environmental, and Geo-Engineering, Univ. of Minnesota, Minneapolis, MN 55455.
5. Professor, Dept. of Civil, Environmental, and Geo-Engineering, Univ. of Minnesota, Minneapolis, MN 55455.
6. Professor, Dept. of Civil, Environmental, and Geo-Engineering, Univ. of Minnesota, Minneapolis, MN 55455 (corresponding author).