Applying Multi-objective Ant Colony Optimization Algorithm For Solving Facility Layout Problems

The facility layout problem belongs to the NP hard problem,and is also a complex combinatorial optimization problem.The study of the facility layout problem has important economic and theoretical significance.In this paper,on the background of the facility layout problem in enterprise production,different constraints handing methods are proposed to optimize the layout according to the different forms of facility layout.The multi-objective ant colony algorithm is used as a global optimization algorithm,and a hybrid algorithm that combines local search and multiple heuristic strategies.The concrete studing contents and results are as follows:(1)Multi-objective ant colony algorithm for static facility layout problem(SFLP)is studied.Based on the quasi-physical strategy,the problem is converted into an unconstrained optimization problem,and a mathematical optimization model is established,and then an improved multi-objective ant colony optimization(MOACO)algorithm is proposed to solve the facility layout problem.In the MOACO algorithm,we propose a novel pheromone update method,and combine the Pareto optimization based on the local pheromone communication and the global search based on the niche technology to obtain Pareto-optimal solutions of the problem.In addition,the heuristic layout updating strategy is proposed to update the layouts in order to add the diversity of solutions,and the combination of the local search based on the adaptive gradient method and the heuristic department deformation strategy is applied to deal with the interface between any two different departments in order to obtain feasible solutions.Ten representative instances from the literature are tested.The experimental results show that the proposed MOACO algorithm is an effective method for solving the SFLP.(2)A multi-objective ant colony algorithm for dynamic facility layout problems(DFLP)is studied.According to the characteristics of the dynamic facility layout problem,a multi-objective ant colony algorithm based on flexible bay structure(MOACO-FBS)is proposed.The definition of the solution in the MOACO-FBS algorithm has been redefined.At the same time,a paired exchange strategy is proposed to increase the quality of the initial solution and the optimization ability of the algorithm.In order to improve the diversity of the solution,the layout updating strategy based on local search is also proposed.Four typical dynamic instances are used to test the algorithm.The experimental results show that the proposed algorithm is an effective method for solving the DFLP.