1. Researcher, Center for Technology and Systems Management (CTSM), Univ. of Maryland, College Park, MD 20742; formerly, Researcher, Dept. of Nuclear Engineering, Seoul National Univ., Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea (corresponding author).
2. Manager, SK Engineering & Construction Co., Ltd., SK G. Plant, 100 Euljiro, Jung-gu, Seoul 100-847, Republic of Korea.