1. Grad. student, Dept. of Civ. Engrg., Mass. Inst. of Tech., Cambridge, Mass.; presently, Engr., Hydronautics, Inc., Laurel, Md
2. Grad. student, Dept. of Civ. Engrg., Mass. Inst. of Tech., Cambridge, Mass
3. Asst. Prof., Dept. of Civ. Engrg., Massachusetts Institute of Technology Cambridge, Mass.; presently, Assoc. Prof. of Clv. Engrg., State Unlv. of N.Y. at Buffalo
4. Assoc. Prof. of Civ. Engrg., Mass. Inst. of Tech., Cambridge, Mass.; presently Dir., Inst. of Hydr. Research, The Univ. of Iowa, Iowa City, Iowa