1. School of Energy and Chemical Engineering; Department of Energy Engineering; Ulsan National Institute of Science and Technology (UNIST); Ulsan 689-798 South Korea
2. School of Chemical and Biological Engineering; Seoul National University; 599 Gwanangno Gwanak-gu Seoul 151-742 South Korea
3. Power Control Device Research Team; Electronics and Telecommunications Research; Institute (ETRI); 218, Gajeongno Yuseong-gu Daejeon 305-700 South Korea