University of Washington, Microsoft, and Stanford
University (U.S.A), Simon Fraser University (Canada), IASBS
(Zanjan, Iran), 2006.
University of Queensland (Australia) 1999, 2000, and 2001.
University of Calgary, University of Manitoba, University of Toronto (Canada), 1996.
University of Queensland (Australia), 1991.
Research Council, Sharif University of Technology, 1985-present.
Research Center, Institute for Theoretical Physics and Mathematics, Iran, 1991-1999.
Raybould Fellow, University of Queensland, 1991 and 1998.
Research Center (Mathematics and Theoretical Physics), AEOI, 1986-1988.
National Science Foundation Fellowship, U. S. A., 1971.
Teaching Assistantship, University of Pennsylvania, 1969 -1975.