Notice of Retraction Improved particle swarm optimization and its application in solving logistics deliver region partition model

Logistics distribution region partition problem is a nondeterministic polynomial problem. It is significant to solve distribution region partition of multi-distribution centers and multi-transfer stations. Logistics distribution region is divided up into different distribution units by cluster methods, multi-distribution centers and multi-transfer stations under the mathematical models of regional division are established based on distribution costs, and an improved particle swarm optimization algorithms are proposed. Because the constraints are implicit added in the evaluation function, and designed dual coding styles about general distribution units choose distribution centers and transfer stations and transfer stations choose distribution centers, therefore, there's a higher global search capability. The simulation results show that the algorithms can more effective solve distribution region partition problems which include large-scale distribution points than PSO and GA algorithms.