1. Department of Advanced Nuclear Engineering, Pohang University of Science and Technology, Pohang, South Korea
2. Department of Electrical and Computer Engineering, Seoul National University, Seoul, South Korea
3. Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang, South Korea
4. Department of Electrical Engineering, Kangwon National University, Chuncheon, South Korea
5. Department of Electrical Engineering, Korea National University of Transportation, Chungju, South Korea
6. Department of Advanced Nuclear Engineering and Department of Physics, Pohang University of Science and Technology, Pohang, South Korea