1. Research Associate, Dept. of Civil and Environmental Engineering, Univ. of Alberta, 9211 - 116 St. NW, Edmonton, AB, Canada T6G 1H9.
2. Associate Professor, Dept. of Structural Engineering, Univ. of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0085.
3. Associate Professor, State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, Hubei 430071, P.R. China.
4. Professor, Dept. of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401.