A model and imperialist competitive algorithm for the two-stage assembly flow shop problem with setup times

The two-stage assembly flow shop with setup times is one of the new production scheduling problems. In this problem, the parts are produced in the first stage and then they are assembled in the second stage. The objective is to sequence parts in the first stage to minimize the makespan. First, a mathematical model in form of a mixed integer linear programming model is developed. Then, to solve the problem, two metaheuristics, imperialist competitive and genetic algorithms, are proposed. The performance of the model and the two algorithms are evaluated by numerical experiments. The result show that the imperialist algorithm works more effectively.