1. Associate Research Fellow, National Center for Research on Earthquake Engineering, 200, Sec. 3, Hsinhai Road, Taipei, Taiwan, R.O.C.
2. Professor, Dept. of Civil and Environmental Engineering, Univ. of Houston, Houston, TX 77204-4791.
3. Research Assistant, National Center for Research on Earthquake Engineering, 200, Sec. 3, Hsinhai Road, Taipei, Taiwan, R.O.C.