1. Ph.D. Candidate, Dept. of Civil Engineering, Univ. of Toronto, 35 St. George St., Toronto, ON M5S 1A4, Canada (corresponding author).
2. Professor, Dept. of Computer Science, Univ. of Toronto, 6 King’s College Rd., Toronto, ON M5S 3G4, Canada.
3. Associate Professor, Dept. of Civil Engineering, Univ. of Toronto, 35 St. George St., Toronto, ON M5S 1A4, Canada.