New results are presented from continuing research dealing with development of a decision support system to assist the Maryland State Highway Administration Office of Maintenance staff in designing snow emergency routes for Calvert County, Maryland. By taking into account some of the more realistic constraints, an attempt is made to solve two problems. One involves minimizing the total number of trucks, and the second one involves minimizing the total deadhead distance given the number of trucks. The two problems do not result in identical solutions in general. The first problem is formulated as the well-known capacitated minimum spanning tree (CMST) problem. The second problem is also formulated as a CMST problem but with an approximate function for total deadhead distance. Some application results are also reported, which indicate that using such a system can achieve improvements in service and savings in operational costs.
Samenvatting