[1] Hitachi Automot Syst Ltd, ECU Design Dept, Elect Device Prod Unit, Ice Business Unit, 2520 Takaba, Hitachinaka, Ibaraki 3128503, Japan
[2] Hitachi Ltd, Ctr Tech Innovat Prod Engn, R&D Grp, Totsuka Ku, 292 Yoshida, Yokohama, Kanagawa 1528550, Japan
[3] Tokyo Inst Technol, Dept Mech Engn, Meguro Ku, 2-12-1 Ookayama, Tokyo 1528550, Japan