1. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, Univ. of Michigan, 2350 Hayward St., Ann Arbor, MI 48109.
2. Principal Research Engineer, SC Solutions, Inc., 1261 Oakmead Parkway, Sunnyvale, CA 94085.
3. Professor, Computer Science and Engineering, Univ. of Michigan, 2260 Hayward St., Ann Arbor, MI 48109.
4. Professor, Dept. of Civil and Environmental Engineering, Univ. of Michigan, 2350 Hayward St., Ann Arbor, MI 48109 (corresponding author).