by
Scott Rob ert Tilley
B.Comp.Sci., Concordia University, 1986 M.Sc., University of Victoria, 1989 A dissertation submitted in partial fulllment
of the requirements for the degree of DOCTOR OF PHILOSOPHY in the Department of Computer Science We accept this dissertation as conforming
to the required standard
Dr. H. A. Muller, Supervisor (Department of Computer Science)
Dr. M. R. Levy, Departmental Member (Department of Computer Science) Dr. W. W. Wadge, Departmental Member (Department of Computer Science)
Dr. V. K. Bhargava, Outside Member (Department of Electrical & Computer Engineering) Dr. P. G. Sorenson, External Examiner (University of Alberta)
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