1. Department of Engineering Science and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Va. 24061
2. System Product Division, D2G6/050-1, IBM Corporation, Rochester, Minn. 55901
3. Equipment Engineering Department, Bldg. 322-M, E. I. DuPont-Savannah River Plant, Aiken, S.C. 29801
4. Dynamics Technology Branch, Boeing Vertol, Philadelphia, Pa.