1. Asst. Prof. of Civ. Engrg., Univ. of Southern California, Los Angeles, Calif.; formerly, Research Fellow in Civ. Engrg., California Institute of Technology, Pasadena, Calif.
2. Prof. of Civ. Engrg., W. M. Keck Lab. of Hydraulics and Water Resources, California Inst. of Technology, Pasadena, Calif.