Prior to joining UMass Lowell in August 2011, he worked at South Carolina State University as an assistant professor for 3.5 years. Xie’s research covers traffic flow modeling, traffic control and simulation, traffic safety (injury severity and crash frequency modeling), GIS-T applications, intelligent transportation systems, network and facility location modeling for emergency response logistics and hazardous materials transportation, and transit operations. Xie is a member of the Transportation Research Board’s (TRB) Transportation Safety Management Committee (ANB10) and Transportation of Hazardous Materials Committee (AT040).