August 2002 - present Associate Professor, Department of Computer Science and Information Engineering, National Chung Cheng University, Chiayi, Taiwan, ROC. February 2001 - July 2002 Assistant Professor, Department of Computer Science and Information Engineering, National Chung Cheng University, Chiayi, Taiwan, ROC. October 1996 - January 2001 Postdoctoral Fellow, Institute of Information Science, Academia Sinica, Taipei, TAIWAN. August 1993 - July 1996 Teaching Assistant and System Manager, Department of Mathematics, National Taiwan University, Taipei, TAIWAN.