1. Dept. of Civil Engineering, Kure College of Technology, 2-2-11, Aga-minami, Kure, Hiroshima, Japan, (E-mail: yamaguti@kure-nct.ac.jp)
2. Hiroshima Prefectural Institute of Industrial Science of Technology, 3-10-32, Kagamiyama, Higashi-hiroshima, Hiroshima, Japan, (E-mail: masanobu@sankaken.gr.jp)
3. Dept. of Civil Engineering, Gifu College of Technology, 2236-2, Kami-makuwa, Motosu, Gifu, Japan, (E-mail: sumino@gifu-nct.ac.jp)
4. Environment System Division, Sanki Engineering Co. Ltd., 1-4-1, Yurakucho, Chiyoda, Tokyo, Japan, (E-mail: akihiro_nagano@eng.sanki.co.jp)
5. Dept. of Civil Engineering, Nagaoka College of Technology, 888, Nishi-katagai, Nagaoka, Niigata, Japan, (E-mail: araki@nagaoka-ct.ac.jp)
6. Dept. of Civil Engineering, Kochi College of Technology, 200-1, Monobe-otsu, Nangoku, Kochi, Japan, (E-mail: syama@ce.kochi-ct.ac.jp)
7. Dept. of Environmental System Engineering, Nagaoka University of Technology, 1603-1, Kami-tomioka, Nagaoka, Niigata, Japan, (E-mail: ecohara@vos.nagaokaut.ac.jp)