1. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Case Western Reserve Univ., Cleveland, OH 44106 (corresponding author).
2. Postdoctoral Researcher, Dept. of Civil, Environmental and Architectural Engineering, Univ. of Kansas, Lawrence, KS 66045.
3. Leonard Case Professor in Engineering, Dept. of Civil and Environmental Engineering, Case Western Reserve Univ., Cleveland, OH 44106.