VEHICLE ROUTING AND SCHEDULING STRATEGIES FOR DEMAND RESPONSIVE TRANSPORTATION SYSTEMS.

摘要

The demand responsive transportation system provides mobility to persons who cannot be served by the traditional fixed-route and fixed-schedule public transportation service. One of the most important ingredients for the success of the demand responsive transportation system is the development of vehicle routes and schedules to handle the individualized travel needs of the users with the limited number of vehicles and drivers. Thus, scheduling of vehicles requires careful consideration to the balance between the operating efficiency and the level of service. This dissertation develops different vehicle routing and scheduling for various sets of objectives and constraints, and applies a model to an actual operation. The models developed are grouped into two types.;The second group of models develops vehicle routes and schedules which minimize the empty vehicle travel, once the individual trips are grouped by geographical zone and time period. Constraints of the models include vehicle capacity, driver shift hours, and the maximum number of trips to be combined in one time period.;One of the models in the second group has been applied for scheduling vehicles for the transportation of the elderly and handicapped persons in the State of Delaware. The features of the system and its performance are discussed including its effects on increasing operating efficiency. Finally, issues related to operation, management, and service for the implementation of a computerized vehicle dispatching system are addressed.;The first group of models develops vehicle routes and schedules which minimize the number of vehicles, given the maximum disutilities of individual users, vehicle capacity, and driver shift hours. Two models of this group use a problem solving method in artificial intelligence for searching the optimum set of trips to be assigned to the drivers.