1. Senior Research Scientist, Dept. of Human Centered Design and Engineering, Univ. of Washington, Campus Box 352315, Seattle, WA 98195 (corresponding author).
2. Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of California Los Angeles, 5732E Boelter Hall, Los Angeles, CA 90095.
3. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Univ. of California Los Angeles, 2541 Boelter Hall, Los Angeles, CA 90095.