The Shortage Study of EOQ Model with Defective and Reworked Items

The main purpose of this paper is to determine the value of economic order quantity (EOQ) with two types of imperfect items, defective and reworked ones, under 100% inspection. Where defective items are treated as scraps and reworked ones will be sent back to supplier to get repaired. A mathematical model is built on the jo in t d ist ribut ion o f defective and reworked un its which fo llow a multivariate hypergeometric distribution given that above two items come from some uniform distribution separately. We extend the study to shortage cases that may occur due to the lack of good items to fulfill demand rate during an order cycle, therefore, it is assumed that manufacturer has to pay additional penalty when the shortage occurs. The expected total cost per unit time is then calculated over its corresponding probabilit ies as well as the expected total cost. Finally, a numerical computation is provided to illustrate the conclusive outcome of proposed model.