Economic production quantity (EPQ) inventory model for trended demand has been analyzed with rework facility and stochastic preventive machine time. Due to the complexity of the model, search method is proposed to determine the best optimal solution. A numerical example and sensitivity analysis are carried out to validate the proposed model. From the sensitivity analysis, it is observed that th...

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...

EPQ model; Replenishment lot size; Multiple deliveries; Random defective items; Production; Rework; Scrap items. Abstract This paper derives the optimal replenishment lot size and shipment policy for an Economic Production Quantity (EPQ) model with multiple deliveries and rework of random defective items. The classic EPQmodel assumes a continuous inventory issuing policy for satisfying demand a...

Huang [ Journal of Statistics and Management Systems, Vol. 6 (2003), No. 2, pp. 171-180 ] studied the EOQ (Economic Order Quantity) and EPQ (Economic Production Quantity) models with backlogging and defective items using the algebraic approach. He assumed 100% inspection policy and the known proportion of defective items was removed prior to storage or use after the screening process. In this p...

The classical economic production quantity (EPQ) model is a well-known and commonly used inventory control technique. Common assumptions in this model are that all units produced are of perfect quality and shortage is not allowed, since in practice shortage, non-conforming product or scrap items are possible, these assumptions will underestimate the actual required quantity. The objective of th...

Recently, the enterprises, from a financial perspective, have been seeing that need of the integrating with others with trade credit policies as a promising issue for savings in the supply chain. In this direction, this paper establishes a new economic production quantity (EPQ) inventory model for deteriorating items under two levels of trade credit, in which the supplier offers to the retailer...

Huang [Mathematical Problems in Engineering, 2006, ID 79028, 1-5] studied the effect of service level constraint on the economic production quantity (EPQ) model with random defective rate. He offered an algebraic approach to replace his differential calculus skill to find the optimal solution under the expected annual cost minimized. In this article, we want to use an easy and simple arithmetic...

Imperfect quality items are unavoidable in an inventory system due to imperfect production process, natural disasters, damages, or many other reasons. The setup cost and production cycle time can be related in terms of process deterioration and learning and forgetting effects. Learning reduces production run length and setup cost, whereas deterioration and forgetting increases both. Keeping the...

In this paper, economic production quantity (EPQ) models for breakable or deteriorating item are developed with variable demands, being dependent on time or on-hand stock. Here rate of production and holding cost are time dependent, unit production cost is a function of both production reliability indicator and production rate. Set-up cost is also partially production rate dependent. The produc...