1. Center for Energy Convergence, Green City Technology Institute, Korea Institute of Science and Technology, Hwarangno 14 gil 5, Seongbuk-gu, Seoul 136-791, Republic of Korea
2. Department of Energy and Environmental
Engineering, Korea University of Science and Technology, 176 Gajungro,
Yuseong-gu, Daejeon 305-350, Republic of Korea