铁路通道牵引定数不一致下的货物始发直达列车优化

he freight load trains which originate at the loading stations are required to carry the bulk cargoes as long as possible, so as to reduce the reclassification operations at marshalling stations during their itineraries, decrease the delivery time and logistics cost, promote the circulation of rolling stock. With the development of low carbon transportation, more and more freights are shifted from roads to railways, causing the freight load train formation plan at the loading stations more complicated. In addition, for a large railway network such as China, not all the railway links have the same hauling capacity because the geographical conditions (for example, certain lines are built in mountains while some are in plains) and investment levels (for example, class I and class II, etc.) of links are different. Therefore, whether to provide the load trains in the lines with individual hauling capacity has become a problem to be solved urgently at the theoretical and application levels. The core problem to be solved in this paper is which traffic flow can be carried by the entire train running through the link with individual hauling capacity, which traffic flows needs to be combined to form a load train disassembled at the yard which is not the first classification station in their itinerary, and which traffic flow sent to the first classification station for assembly. The objective function is to minimize the total cost of operating all shipments at the loading and the unloading stations, and the cost during itineraries under different train formation patterns. Among them, the waste of transportation capacity of certain lines caused by running the load trains with the lowest train weight is considered in the itinerary cost. Considering that each traffic flow can only be included in one type of train, the mathematical form of the model is a 0-1 programming model.