1. Visiting Scholar, Dept. of Civil and Environmental Engineering, Univ. of Michigan, 2350 Hayward St., Room 1350, G. G. Brown Bldg., Ann Arbor, MI 48109.
2. Professor, Dept. of Civil and Environmental Engineering, Univ. of Michigan, 2350 Hayward St., Room 2340 G. G. Brown Bldg., Ann Arbor, MI 48109.
3. Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of Michigan, 2350 Hayward St., Room 2322 G. G. Brown Bldg., Ann Arbor, MI 48109.