• Instructor, Huazhong University of Science & Technology, PRC, 1985 - 1986
• Teaching Assistant, Iowa State University, 1986 - 1987
• Research Assistant, Iowa State University, 1987 - 1989
• Teaching Assistant, Iowa State University, 1989 - 1990
• Assistant Professor, University of Louisiana at Lafayette, 1990 - 1995
• Associate Professor, University of Louisiana at Lafayette, 1995 - 2001
• Professor, University of Louisiana at Lafayette, 2001-present
• Graduate Coordinator, Department of Mathematics, 2005-2010
• Head, Department of Mathematics, 2013-2017