In this paper, an inventory model for two-stage supply chain is investigated. A supply chain with single vendor and single buyer is considered. We assume that shortage as a backorder is allowed for the buyer and the vendor makes the production set up every time the buyer places an order and supplies on a lot for lot basis. With these assumptions, the joint economic lot size model is introduced ...

This paper considers the basic economic order quantity (EOQ) model when all parameters, such as the demand rate, the ordering cost, and the inventory holding cost, are uncertain, and furthermore, their probability information is also unknown. To address the uncertainty, we adopt a robustness-based approach. In this approach, each unknown parameter is described as a continuous value restricted t...

Deciding shipment size is important in freight transport: it depends on the logistical imperatives of shippers and the technical possibilities of carriers. Shipment size choice is also closely related to transportation mode; it is therefore important from a public policy perspective. The theory of optimal shipment size and mode choice is robust. There are many inventory-theoretical models of op...

We review historical patterns of "economic geography" for the United States from the colonial period to the present day. The analysis is framed in terms of two geographic scales: regions and cities. The compelling reason for studying geographic areas of different scales is that models that explain the location of economic activities at one scale many not apply to other scales. We consider the p...

The main purpose of this paper wants to investigate the optimal retailer’s lot-sizing policy with two warehouses under partially permissible delay in payments within the economic order quantity (EOQ) framework. In this paper, we want to extend that fully permissible delay in payments to the supplier would offer the retailer partially permissible delay in payments. That is, the retailer must mak...

An order level inventory system for deteriorating items has been developed with demand rate as a ramp type function of time. The finite production rate is proportional to the demand rate and deterioration rate is time proportional. The unit production cost is inversely proportional to the demand rate. The model with no shortage case in inventory is first solved. The inventory shortage is discus...

While deterioration models consider the gradual reduction in quality and quantity of products over time, amelioration models assume the opposite. This paper is based on an earlier work by Hwang for finding an optimal economic order quantity solution for items subject to amelioration in a Weibull distribution. Hwang solved the problem with a graphical procedure. In this paper, a rigorous analyti...

Several authors have developed models for the EOQ when only a percentage of stockouts will be backordered. Most of these models are complicated, with equations unlike those for the EOQ with full backordering. In this paper we extend work by Pentico and Drake [The deterministic EOQ with partial backordering: a new approach. European Journal of Operational Research 2008; in press] that developed ...

The economic order quantity (EOQ) model is the simplest and earliest inventory model in the literature. Its simple mathematics is attributed to its assumptions, which are rarely met. Salameh and Jaber [2000. Economic production quantity model for items with imperfect quality. Int. J. Prod. Econ. 64, 59–64] addressed one of these assumptions that items received or produced are not of perfect qua...