1. Professor, Geosphere Research Institute, Saitama University, 255 Shimo-ohkubo, Sakura-ku, Saitama 338-8570, Japan, Telephone: +81 48 858 9239; Telefax: +81 48 855 1378; E-mail: jkuwano@mail.saitama-u.ac.jp
2. Professor, Department of Civil and Environmental Engineering, National Defense Academy, 1-10-20 Hashirimizu, Yokosuka 239-8686, Japan, Telephone: +81 468 41 3810; Telefax: +81 468 44 5913; E-mail: miyamiya@nda.ac.jp
3. Professor, Institute of Industrial Science, University of Tokyo, Ce201, IIS, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan, Telephone: +81 (3 5452 6421; Telefax: +81 3 5452 6423; E-mail: koseki@iis.u-tokyo.ac.jp