Improved discrete particle swarm optimization based on edge coding and multilevel reduction strategy for larger scale TSP

In order to improve particle swarm optimization (PSO) to solve complex and large scale discrete optimization problems, the paper introduces an improved discrete particle swarm optimization (IDPSO) based on edge coding and multilevel reduction strategy. First, redefine the velocity and position of the particle based on edge-coding, and adopted converted insertion of the edge to update the information of the particle. Next, introduce multilevel reduction strategy to improve the global convergence ability of the algorithm. The improved algorithm is applied to solve representative cases of traveling salesman problem (TSP), The results show that the improved DPSO is efficient and valid on the complex TSP, and the multilevel reduction strategy can contribute to develop the ability of PSO when facing up to the complex and large scale problems greatly.