the traditional economic production quantity (epq) model assumes that during the production process no imperfect item is produced. but in the real production system, due to imperfect production process or other factors, imperfect quality items may be produced. furthermore, it is well-known that the total production-inventory costs can be reduced by reworking the imperfect quality items produced...

In the traditional economic order quantity/economic production quantity model, most of the items considered are of perfect type. But this situation rarely takes place in practice. Thus, in this paper, an economic order quantity model with imperfectquality items is developed. 100% screening process is performed, and the items of imperfect quality are sold as a single batch. A proportionate ra...

In this paper, two economic production quantity (EPQ) models are proposed for deteriorating/imperfect items with rework process. The production process is imperfect, and imperfect quality items are reworked to become serviceable. At the same time, the remaining good quality items may deteriorate. The inspection of deteriorated items is also imperfect, so that deteriorated items may be sold to c...

This paper deals with an economic order quantity model where demand is stock dependent. Items received are not of perfect quality and each lot received contains percentage defective imperfect quality items, which follow a probability distribution. Two cases are considered. 1) Imperfect quality items are held in stock and sold in a single batch after a 100 percent screening process. 2) A hundred...

The basic assumption in the traditional inventory model is that all outputs are perfect items. However, this assumption is too simplistic in the most real-life situations due to a natural phenomenon in a production process. From this it is deduced that the system produces non-perfects items which can be classified into four groups of perfect, imperfect, reworkable defective and non-reworkable d...

This paper extends an imperfect production inventory model to machine breakdown at a random time and rework of defective items. Any manufacturing system wants to produce perfect quality items. But in long run production process, there may arise different types of difficulties like labor problem, rawmaterial problems, operator problems, etc., due to that the machinery systems shift from in-contr...

 The paper considers an integrated production, inspection, preventive maintenance, and inventory problem and determines the optimal inspection interval, inspection frequency, and production quantity yielding the maximum unit expected profit in an imperfect production process with inspection time and reworking. When the process in an out-of-control state produces a certain percentage of non-con...