1. Research Fellow, Nottingham Transportation Engineering Centre, Univ. of Nottingham, Nottingham NG7 2RD, UK; formerly, Research Scientist, Virginia Center for Transportation Innovation and Research, Charlottesville, VA (corresponding author).
2. Director of Engineering, Virginia Asphalt Association, 6900 Patterson Ave., Richmond, VA 23226.
3. Assistant Asphalt Program Manager, Virginia Dept. of Transportation, 1401E Broad St., Richmond, VA 23219.