We are especially thankful to Dr. Carlos J. Lozano for his continuous interest and helpful collaboration. We thank Mr. Todd Alcock, Mr. Michael Landes, and Mrs. Renate D’Arcangelo for preparing some of the figures and portions of this manuscript. We are grateful to two anonymous referees for their excellent reviews. PFJL is very indebted to Professors Donald G. Anderson, Andrew F. Bennett, Roger W. Brockett, and Brian F. Farrell, members of his dissertation committee, for their challenging guidance and encouragements. PFJL also benefited greatly from several members of the Harvard Oceanography Group, past and present. This study was supported in part by the Office of Naval Research under Grants N00014-95-1-0371 and N00014-97-1-0239 to Harvard University.
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