1. Structural Engineer, Kayson Company, Tehran, Iran; formerly, Graduate Student, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst, MA 01003.
2. Associate Professor, Dept. of Natural Resources Conservation, Univ. of Massachusetts, Amherst, MA 01003 (corresponding author).
3. Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, 223 Marston Hall, Amherst, MA 01003.