1. Assoc., School of Civ. and Environmental Engrg., Cornell Univ., Ithaca, N.Y.
2. Prof., School of Civ. and Environmental Engrg., Cornell Univ., Ithaca, N.Y.
3. Assoc. Prof., School of Civ. and Environmental Engrg., Cornell Univ., Ithaca, N.Y.; currently Visiting Assoc., W. M.ASCE Keck Lab., California Instit. of Tech., Pasadena, Calif.