Optimal cycle time for production-inventory systems considering shelf life and backordering

摘要

Recently shelf life during which the items remain safe within the production plants is considered in production optimisation models. This paper addresses manufacturing system with multiple items produced on a single facility having shelf life restrictions and backorders. Backorders incur shelf life constraint alteration, affecting the corresponding inventory models. Accordingly, appropriate modifications are applied to the related mathematical models. The purpose is to determine the optimal cycle time and minimise the long-run average costs. While the cost-minimisation cycle time causes the spoilage of a product due to the shelf life restrictions, proper decisions are made based on one of the three options: production rate reduction, cycle time reduction, and a combination of both. For each option, optimal cycle time and production rate are estimated to satisfy shelf life constraint. Numerical examples are presented to illustrate the influence of production cost, backorders, and shelf life on total cost.