This article presents a perishable (s; S) inventory system under continuous review at a service facility in which a waiting hall for customers is of nite size M. The arrival instants of customers to the service station constitutes a Poisson process. The life time of each items is assumed to be exponential. All arriving customers demand the rst "essential" service, whereas only some of them dema...

Consider an inventory system with multiple supply sources and Poisson demand. The replenishment leadtimes from each source are stochastic, representing congestion and disruption. We develop performance evaluation and optimization tools for a family of reasonable order policies. These policies take into account real-time supply information, which can be obtained through tracking technologies suc...

Consider a two-level inventory system consisting of one supplier and one retailer. The retailer faces a Poisson demand with a known rate and applies base stock (one-for-one ordering) policy. That is, his inventory position is set to a pre-determined level, so the demand pattern is transferred exactly to the supplier. The supplier has an inventory system and a service unit with exponentially dis...

This paper presents a three-level supply chain model which includes single supplier, several distribution centers and sets of retailers. For this purpose, by adopting the queuing approach, a mixed nonlinear integer programming model is formulated. The proposed model follows minimizing the total cost of the system by determining: 1) the number and location of distribution centers between candida...

In this paper, we consider stock rationing problem of a single-item make-to-stock production/inventory system with multiple demand classes. Demand arrives as a Poisson process with a randomly distributed batch size. It is assumed that the batch demand can be partially satisfied. The facility can produce a batch up to a certain capacity at the same time. Production time follows an exponential di...

This paper considers a single-echelon, continuous review, inventory system with a warehouse facing compound Poisson customer demand. The replenishment lead-time is constant. Demand that cannot be met directly is backordered. There are standard linear holding and backorder costs but no set-up or ordering cost. It is assumed that the demand process starts at a certain given time. Consequently, be...

Abstract In this paper we consider a system consisting of a retailer, a supplier with a single processing unit, and a repair center. We assume that the retailer faces a Poisson demand, his ordering cost is zero or negligible, and for his inventory control he applies one-for-one ordering policy, that is, as soon as a demand arrives he orders one unit to the supplier. We also assume that when a d...

this paper deals with an i * corresponding author email address:   nventory system with one central warehouse and a number of identical retailers. we consider perishable-on-the-shelf items; that is, all items have a fixed shelf life and start to age on their arrival at the retailers. each retailer faces poisson demand and employs (1, t) inventory policy. although demand n...