Terminal Constraints for Single-stage Multi-product Scheduling Problems

In scheduling, it is important to maintain the terminal inventory levels above threshold values to prevent stockout. However, simply enforcing the terminal inventory level above a lead-time-based threshold for each product, as it is common practice, does not exploit the relationships of inventory levels among products. To overcome this drawback, we propose a new type of terminal constraints for single-stage problems, considering singleand multi-unit facilities. Replacing the traditional lead-time-based constraints with the proposed linear terminal constraints leads to better closed-loop solutions. Using different examples, we show how to obtain the terminal constraints, and we verify their effectiveness using instances with and without uncertainty.