1. C. H. Davis, Department of Electrical Engineering, University of Missouri, 5605 Troost Avenue, Kansas City, MO 64110, USA.
2. C. A. Kluever, Department of Mechanical and Aerospace Engineering, University of Missouri, 5605 Troost Avenue, Kansas City, MO 64110, USA.
3. B. J. Haines, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA.