1. Department of Mechanical Systems Engineering, Kanagawa Institute of Technology, 1030 Shimoogino, Atsugi, Kanagawa 243-02, Japan
2. Department of High Temperature Engineering, Japan Atomic Research Institute, Tokaimura, Naka-gun, Ibaraki 319-11, Japan
3. Department of ITER Project, Japan Atomic Research Institute, Nakamachi, Naka-gun, Ibaraki 311-02, Japan