1. Department of Resources and Environmental Engineering; Faculty of Science and Engineering; Waseda University; Ohkubo 3-4-1, Shinjuku-ku Tokyo 169-8555 Japan
2. National Research Institute for Cultural Properties; Tokyo, Ueno Park 13-43, Taito-ku Tokyo 110-8713 Japan
3. Research Center in Architecture and Engineering; C.R.A.I.-F.R.E. 3315 MAP CNRS/MCC France