Model And Algorithm For Vehicle Routing Problem Based On Strategy Of Replenishment Along Route

A huge difference has taken part in logistics distribution due to the dynamic environment: from the part of distraction, the scale of logistics business is increasing and the areas of logistics service are integrating; from the part of time, the lower needs are becoming more and more and requirement cycles and the lead time reduced; from the part of service level of logistics enterprises, quick response to market demands and flexibility of logistics system have become the primary performance indicators to the logistics ability. As the distribution networks of logistics system is becoming multi-warehouse, multi-demand in a large scale, a flexible structure is badly needed which can quickly respond to market and adapt to stochastic demands.In terms of the changes of logistics environment, the traditional zonal allocation distribution model is discarded and a new cross-area joint distribution network which is a many to many network is built on the whole. besides, a strategy of replenishment along route(SRR) is adopted during the vehicle routing planning, which can not only be used to balance the logistics load of different areas , have the logistics resources got shared in a large scale and also improve the flexibility and quick response ability. in the paper, five mathematical model and five heuristic algorithms have been proposed as discussed below:(1).Closed-ring vehicle routing problem model and algorithm based on the routing planning strategy of replenishment along route, in which the batch-inserted heuristic algorithm based on the geometrical analysis construct a single-chain vehicle route and improved gradual saving heuristic algorithm is a solution that has many chains. Simulation test showed those algorithms can get the results improved respectively by 14% and 18% compared to the traditional ones.(2). The model and algorithm of open vehicle routing problem(OVRP) based on the routing planning strategy of replenishment along routes, consists of tow models and algorithms: gradual saving heuristic algorithm and time-constrained OVRP model based on SRR ,which can solve the curved routes and the optimization is more than 10%; diverse random OVRP model based on SRR, which is to be transferred to a certain problem so as to get the solution through software or the certain problem algorithm.(3). The model and algorithm of hybrid vehicle routing problem based on the routing planning strategy of replenishment along routes, consists of two models and algorithms: hybrid vehicle routing problem model based on SRR and ant-colony algorithm with replenishment factors; hybrid vehicle routing problem model with soft time window based on SRR and its colony algorithm. Simulation test showed high optimization and stability of this algorithm.