Vehicle Routing Problem With Simultaneous Pickup And Delivery Based On Niching Particle Swarm Optimization

In this paper,the author make a research about the vehicle routing problem with simultaneous pick-up and delivery(VRPSPD). First, the authorintroduce the basic theory of VRP and the common methods to resolve it.And then,the author make the model of the VRPSPD with the aim of minizing the total cost.In order to solve and optimize the VRPSPD, the author introduce the niche technique into the stand particle swarm optimization(PSO),based on its wide use in thegenetic algorithm.And then,make the scheme of the niche generating and eliminating in order to avoid the matter of too early weaken.The author also improved the status formula on two sides.First,the author improved inertia factor in the PSO update formula to make it more adjustable, thus make a balance between the PSO's local and global search ability.Second,the author added local best place in the niche's sub swarm,and make it more convergence.In this paper,the author develop a program of the Stand PSO and Niche PSO under the Matlab IDE.In order to verify the NPSO's efficiency,the author make a compare between the PSO and NPSO via the testing of VRP benchmark,and then prove that NPSO has better ability to get the good solution.then,the author apply the NPSO to seveal VRP benchmarks.In order to verify the effectiveness and efficiency of the NPSO, the author make a large number of simulation experiments above the Christophides instances Solomon instances. By comparing with the best known solution of the literature,it proves that the NPSO has quite well the feasibility and validity of the proposed method which can obtain the efficient solution within short time. Therefore,it can be used to solve the real-life large-scale vehicle routing problem.At last,the thesis predicts the application prospect of the improved particle swarm optimization and gives some directions of future research.