Article ID: | iaor20122465 |
Volume: | 63 |
Issue: | 4 |
Start Page Number: | 497 |
End Page Number: | 510 |
Publication Date: | Apr 2012 |
Journal: | Journal of the Operational Research Society |
Authors: | Bijvank M, Vis I F A |
Keywords: | inventory, simulation: applications, combinatorial optimization |
Most inventory management systems at hospital departments are characterised by lost sales, periodic reviews with short lead times, and limited storage capacity. We develop two types of exact models that deal with all these characteristics. In a capacity model, the service level is maximised subject to a capacity restriction, and in a service model the required capacity is minimised subject to a service level restriction. We also formulate approximation models applicable for any lost‐sales inventory system (cost objective, no lead time restrictions etc). For the capacity model, we develop a simple inventory rule to set the reorder levels and order quantities. Numerical results for this inventory rule show an average deviation of 1% from the optimal service levels. We also embed the single‐item models in a multi‐item system. Furthermore, we compare the performance of fixed order size replenishment policies and (R,s,S) policies.