1. Department of Control and Instrumentation Engineering, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea
2. Department of Information and Communication Engineering, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea
3. Department of Computer and Information Science, Korea University, Jochiwon-eup, Yeongi-gun, Chungnam 339-700, Republic of Korea
4. Department of Control, Instrumentation and Robot Engineering, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea