*Koumei Nagai1, Akira Kodaira1, Takashi Maruyama1, Satoshi Oku1, Hiroshi Kumagai2, Bokor Nándor3, Yoshinori Iketaki2,4
(1. NTT Advanced Technology Corporation, 2. Kitasato University, 3. Budapest University of Technology and Economics, 4. Olympus Corporation)