An improved ant colony optimization algorithm for the vehicle routing problems with time windows

This paper presents an improved scheme for the vehicle routing problems with time windows based on ant colony optimization algorithm. The new scheme makes the change of heuristic message fast and speeds the convergence process by improving updating method of global pheromone and visibility strategy. Simulation results from eight groups of vehicle transportation case show that the new scheme performs better in vehicle routing problems. It can reduce the iteration times and make optimization solution in a short time.