In this paper, we conduct a simulation study to evaluate the impact of using imperfect advance demand information (ADI) in a single stage production/inventory system. We mean by ADI the fact that the production system receives customer orders in advance of their due-dates. We consider four types of ADI: 1) Perfect ADI, 2) ADI with imperfect due-dates, 3) ADI with imperfect demand quantities and...

We consider two reverse logistics systems where returned products are as good as new. For the first system, the product return flow is independent of the demand flow.We prove that the optimal policy is of base-stock type and we establish monotonicity results for the optimal base-stock levels, with respect to the system parameters (arrival rate, production rate, return rate, production cost, los...

We study single and multistage inventory systems with stochastic lead times. We study a class of stochastic lead time processes, which we refer to as exogenous lead times. This class of lead time processes includes as special cases all lead time models from existing literature (such as Kaplan’s lead times with no order crossing or independent and identically distributed lead times with order cr...

We consider a serial production system controlled by the base-stock policy, in which customer demands must be satisfied immediately or it will be considered lost. Since the exact analysis is impossible for the general system,we present a phase-type approximation for a base-stock controlled serial production system. The numerical results indicate that this approximation provides good estimates f...

In this paper, we consider a serial two-echelon periodic review inventory system with two supply modes at the most upstream stock point. As control policy for this system, we propose a natural extension of the dual-index policy, which has three base-stock levels. We consider the minimization of long run average inventory holding, backlogging, and both per unit and fixed emergency ordering costs...

We make a novel connection between an energy-efficient wireless transmission scheduling problem and a multi-period, multi-item inventory control problem with stochastic convex ordering costs, deterministic demands, and a joint budget constraint. In the special case of a single item, we show that a state-dependent modified base-stock policy is optimal when the stochastic ordering costs are linea...

We consider a two-echelon inventory system where the exogenous demands occur only at the retailer locations, and the demand rates are functions of an underlying continuoustime Markov chain. This underlying process may represent, for example, general economic conditions, the number of active users in the system, etcetera. Each retailer location follows a base-stock policy that is independent of ...

We consider a periodic-review inventory system with one warehouse and N non-identical retailers. Each location replenishes inventory according to a base-stock policy in a fixed time interval. A fixed cost is incurred for each inventory reorder. The warehouse fills the retailers’ orders in the same sequence as the original demand. The objective is to minimize the long-run average system cost per...

The problem is to determine a review period and stocking policy that are mutually bene®cial to a producer and a retailer. In our model, the retailer uses a periodic review, base stock policy for ordering the item from the producer's Distribution Center (DC). Excess customer demand is assumed to be lost. A make-to-order production system supplies to the DC. We show that given a review period, un...

Variability, in general, has a deteriorating effect on the performance of stochastic inventory systems. In particular, previous results indicate that demand variability causes a performance degradation in terms of inventory related costs when production capacity is unlimited. In order to investigate the effects of demand variability in capacitated production settings, we analyse a make-to-stock...