The Multiple Traveling Salesman Problem with Time Windows: Bounds for the Minimum Number of Vehicles
نویسندگان
چکیده
This paper deals with finding a lower and an upper bound for the minimum number of vehicles needed to serve all locations of the multiple traveling salesman problem with time windows. The two types of precedence graphs are introduced – the start-time precedence graph and the end-time precedence graph. The bounds are generated by covering the precedence graph with minimum number of paths. Instances for which bounds are tight are presented, as well as instances for which bounds can be arbitrary bad. The closeness of such instances is discussed.
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