A GENETIC ALGORITHM FOR SOLVING THE ECONOMIC LOT SCHEDULING PROBLEM WITH REWORKS

In this study, we are interested in the economic lot scheduling problem (ELSP) with reworks in which the production system deals with two sources of products: manufacturing of the serviceable products and remanufacturing of the rework products. We may consider that these two categories of products compete for the same facility and they must be scheduled simultaneously. In this paper, we formulate a mathematical model for the ELSP with reworks using the common cycle (CC) approach in which only one manufacturing lot and only one rework lot for each product exist during a common cycle, and all the products share the same replenishment cycle. In order to solve this problem, we propose a hybrid genetic algorithm (GA) approach that obtains an optimal production sequence of all manufacturing and rework lots with the lowest average total cost. Our numerical examples demonstrate the effectiveness of the proposed hybrid GA.