A Two-Echelon (R, Q) Inventory Model: A Genetic Algorithm and Imperialist Competitive Algorithm Approach

In this paper, a two-echelon inventory system is presented that implements (R, Q) policies at each inventory holding point (IHP) for each non-repairable spare part at each echelon that contains assumptions that limit the real world applications. This paper in order to expand this model and increase its application, assumes that orders are discretely and warehouse space is limited. In the new condition, modeling is carried out and then for solving the model, genetic algorithm (GA) and imperialist competitive algorithm are expanded and calibrated. Also, efficiency of algorithms is evaluated with comparing their operations.