Yuh-Jiun Chen, Chin-Chen Chang*and Wei-Pang Yang#
Institute of Computer Science and Information Engineering
National Chiao Tung University
Hsinchu, Taiwan, R.O.C.
*Institute of Computer Science and Information Engineering
National Chung Cheng University
Chiayi, Taiwan, 621, R.O.C.
#Institute of Computer and Information Science
National Chiao Tung University
Hsinchu, 300, Taiwan, R.O.C.