1. Department of Industrial Engineering, Seoul National University, Seoul 151-744, Republic of Korea
2. Samsung Electronics, Suwon, Gyeonggi-do 443-742, Republic of Korea
3. Agency for Defense Development, Daejeon 305-152, Republic of Korea
4. Department of Industrial and Management Engineering, Hanyang University, Ansan, Gyeonggi-do 425-791, Republic of Korea