An EOQ model for imperfect quality items with multiple quality characteristic screening and shortage backordering

In this paper, we propose an inventory model where items are inspected through multiple screening processes on varies quality characteristics before delivery to customers. Each screening process on a single quality characteristic has independent screening rate and defective percentage. Defective items screened out are stored and then returned to supplier. Shortage backordering are also allowed in the model. Two approaches are used to obtain the closed-form optimal order size and the maximum backordering quantity. Numerical examples are also provided to demonstrate the use of the model.