Haralabos Christos Papadopoulos.Includes bibliographical references (p. 163-165).Also issued as a Ph.D. thesis, Dept. of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 1998.Sponsored by the Advanced Research Projects Agency monitored by the Office of Naval Research. N00014-93-1-0686 Sponsored by the Air Force Office of Scientific Research. F49620-96-1-0072 Sponsored in part by the U.S. Army Research Laboratory under the Federated Laboratory Program. Cooperative Agreement No. DAAL01-96-2-0002