1. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Univ. of Delaware, 301 DuPont Hall, Newark, DE 19716 (corresponding author).
2. Graduate Research Assistant, Dept. of Geodesy and Geomatic Engineering, Univ. of New Brunswick, Fredericton, NB, Canada E3B 5A3.
3. Professor, Dept. of Civil and Environmental Engineering, Univ. of Delaware, 354 DuPont Hall, Newark, DE 19716.
4. Professor, Dept. of Computer and Information Sciences, Univ. of Delaware, Newark, DE 19716-2712.