Hitachi Research Laboratory, Hitachi, Ltd., 832-1 Horiguchi, Hitachinaka, Ibaraki, Japan
Hitachi Research Laboratory, Hitachi, Ltd., 832-1 Horiguchi, Hitachinaka, Ibaraki, Japan
Copyright © 2013 Hiroyuki Toyoda, Yoshihiro Kondo et al. This is
an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any
medium, provided the original work is properly cited.