Affiliation: | 1. Department of Industrial Engineering, CAESIT Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701, Republic of Korea;2. College of Advanced Engineering, Kyung Hee University, 1 Seocheon-ri, Kihung-eup, Yongin-si, Kyunggi-do 449-701, Republic of Korea;3. Department of Industrial and Information Systems Engineering, Seoul National University of Technology, 172 Kongneung 2-dong, Nowon-gu, Seoul 139-743, Republic of Korea |