Wei-Hua He, Tzong-Chen Wu* and Chih-Yin Lin**
Department of Information Management
Chaoyang University of Technology
Taichung, 413 Taiwan
E-mail: whhe@mail.cyut.edu.tw
*Department of Information Management
National Taiwan University of Science and Technology
Taipei, 106 Taiwan
E-mail: tcwu@cs.ntust.edu.tw
**Institute of Information Management
National Chiao Tung University
Hsinchu, 300 Taiwan
E-mail: u8534502@cc.ncu.edu.tw