1. Hitachi
Research Laboratory, Hitachi, Ltd., 7-1-1 Omika-cho, Hitachi 319-1292, Japan
2. Fracture and Reliability
Research Institute, Graduate School of Engineering, Tohoku University, 6-6-11 Aoba, Aramaki,
Aoba-ku, Sendai 980-8579, Japan
3. WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1
Katahira, Aoba-ku, Sendai 980-8577, Japan
4. Institute of Multidisciplinary Research
for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan