1. Visiting Associate Professor, Univ. of Wisconsin–Madison; Associate Professor, Marquette Univ., Milwaukee, WI 53233. E-mail: chris.foley@marquette.edu
2. Emison Professor of Civil Engineering, Dept. of Civil Engineering, Univ. of Memphis, Memphis, TN 38152. E-mail: spezeshk@memphis.edu
3. Senior Seismic Research Engineer, John A. Martin and Associates, Inc., Los Angeles, CA 90015. E-mail: arzhang@johnmartin.com