Affiliation: | a Hitachi Engineering Co., Ltd., Saiwai-cho, Hitachi-shi, Ibaraki-ken 317-0073, Japan b Hitachi Ltd., Saiwai-cho, Hitachi-shi, Ibaraki-ken 317-8511, Japan c Nuclear Power Engineering Corporation (NUPEC), Toranomon, Minato-ku, Tokyo 105-0001, Japan d Nippon Nuclear Fuel Development Co Ltd. (NFD), Oarai-machi, Ibaraki-ken 311-1313, Japan |