Michael D. Richard.Includes bibliographical references (p. 209-214).Supported by the U.S. Air Force Office of Scientific Research under the Augmentation Awards for Science and Engineering Research Training Program Grant. F49620-92-J-0255 Supported by the U.S. Air Force Office of Scientific Research. AFOSR-91-0034-C Supported by the U.S. Navy Office of Naval Research. N00014-93-1-0686 Supported by Lockheed Sanders, Inc. under a U.S. Navy Office of Naval Research contract. N00014-91-C-0125