A sustainable production-inventory model joint with preventive maintenance and multiple shipments for imperfect quality items

The quality of products, maintenance activities, and transportation policies are primary concerns of managers in inventory and production planning problems. Environmental issues and regulations are growing increasingly and they have attracted much attention to achieve sustainable production. Previous authors have conducted a wide range of studies on these problems separately. Regarding the gap of an integrated framework, a sustainable economic production quantity model is formulated by considering preventive maintenance and multiple shipments policy where a portion of produced items is defective. Two particular cases are studied. In Case I, the production period's demand has been satisfied by the items produced in the previous cycle. In Case II, simultaneous production and consumption during the production period are considered and mathematically formulated. An analytical method is presented for solving the models, and a numerical example is discussed for both cases. The comparison of two cases proves that Case II is more beneficial and the overall cost of the inventory system is reduced. Sensitivity analysis of the models is performed, and some insights are derived by changing some of the parameters. (c) 2023 Sharif University of Technology. All rights reserved.