ali salmasnia - Department of Industrial Engineering, Faculty of Engineering and Technology, University of Qom
hossein fallah ghadi - Department of Industrial Engineering, Faculty of Engineering and Technology, University of Qom
hadi mokhtari - Department of Industrial Engineering, Faculty of Engineering, University of Kashan, Kashan

Achieving optimal production cycle time for improving manufacturing processes is one of the common problems in production planning. During recent years, different approaches have been developed for solving this problem, but most of them assume that mean quality characteristic is constant over production run length and sets it on customer’s target value. However, the process mean may drift from an in-control to an outof-control at a random point in time. This study aims to select the production cycle time and the initial setting of mean quality characteristic, so that the expected total cost, consisting of quality loss and maintenance costs as well as ordering and holding costs, already considered in the classic models is minimized. To investigate the effect of mean process setting, a computational analysis on a real world example is performed. Results show the superiority of the proposed approach compared to the classical economic production quantity model

Production planning,deterioration process, production run length, mean quality characteristic, drift, Loss function