1. Department of Structural Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92037, USA
2. Department of Modern Mechanical Engineering, Waseda University, 1-6-1 Nishi-Waseda, Shinjuku-ku, Tokyo 169-8050, Japan
3. Mechanical Engineering, Rice University — MS 321, 6100 Main Street, Houston, TX 77005, USA