1. Graduate School of Engineering, Tohoku University, Aoba 6-6-11-1209, Aramaki, Aoba, Sendai, Miyagi 980-8579, Japan.
2. College of Engineering and Design, Shibaura Institute of Technology, 3-9-14 Shibaura, Minato-ku, Tokyo 108-8548, Japan.
3. School of Engineering, Cardiff University, Cardiff CF24 3AA, UK.