1. Research Unit 1, Research and Development Directorate, Japan Aerospace Exploration Agency (JAXA), Sengen 2-1-1, Tsukuba, Ibaraki 305-8505, Japan
2. Nuclear Engineering and Management, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
3. Nuclear Professional School, School of Engineering, The University of Tokyo, 2-22 Shirakata-shirane, Tokai-mura, Naka-gun, Ibaraki 319-1188, Japan
4. Graduate School of Engineering, Kobe University, Rokko-dai 1-1,
Nada, Kobe, Hyogo 657-8501, Japan