Research On Optimization Algorithm For Vehicle Routing Problem With Simultaneous Pickup And Delivery

With the rapid development of China’s economy and the prevalence of online economy,the logistics industry has developed rapidly.More and more logistics orders make the transportation and distribution activities gradually routine.Reasonable planning of distribution routes to reduce costs and increase efficiency has become the focus of current research.Based on the actual demand for timely replenishment and delivery in the real production field,this thesis studies the optimization algorithm for solving the vehicle routing problem with simultaneous pickup and delivery(VRPSPD)with the goal of minimizing the logistics and transportation costs.This thesis mainly focuses on the improved seagull algorithm for solving VRPSPD model.The specific research contents are as follows:1.A Discrete Seagull Optimization Algorithm(DSOA)is proposed.Searching the neighborhood of the best location in the seagull group reduces the dependence on the best individual;Redefining the migration behavior and attack behavior of seagulls not only expands the search space of the algorithm,but also improves the optimization ability of the algorithm;Simulated annealing algorithm is used to enhance the ability of the algorithm to escape the local optimum.2.An improved discrete seagull algorithm based on operator tuning(OT-DSOA)is proposed.Using the method of analyzing the fitness landscape,the distance and entropy between the initial solution of the population and the corresponding optimal solution are calculated,which can be used as guidance information to adjust the inappropriate customer point position in the route,thus improving the solution quality of the algorithm.DSOA,OT-DSOA and other algorithms are compared and verified on the Solomon standard dataset,and the results show that the improved strategy is feasible and effective.In addition,the improved seagull algorithm was successfully used to plan the driving path of the oil tanker in an oil production plant,which fully shows that the solution of VRPSPD using the improved seagull algorithm has certain guiding significance for the actual logistics activities.