An Integrative Approach To Inventory Control

Abstract

Inventory control systems consist of three types of methods: forecasting, safety stock sizing and order timing and sizing. These are all part of the interpretation of a planning environment to generate replenishment orders, and may consequently affect the performance of a system. It is therefore essential to integrate these aspects into a complete inventory control process, to be able to evaluate different methods for certain environments as well as for predicting the overall performance of a system. In this research a framework of an integrated inventory control process has been developed, covering all relations from planning environment to performance measures. Based on this framework a simulation model has been constructed; the objective is to show how integrated inventory control systems perform in comparison to theoretical predictions as well as to show the benefits of using an integrated inventory control process when evaluating the appropriateness of inventory control solutions. Results indicate that only simple applications (for instance without forecasts or seasonality) correspond to theoretical cost and service level calculations, while more complex models (forecasts and changing demand patterns) show the need for tight synchronization between forecasts and reordering methods. As the framework describes all relations that affect performance, it simplifies the construction of simulation models and makes them accurate. Another benefit of the framework is that it may be used to transfer simulation models to real-world applications, or vice versa, without loss of functionality.