We examine a single-item, periodic-review inventory system with stochastic leadtimes, in which a replenishment order is delivered immediately or one period later, depending probabilistically on costly effort. The objective is to determine an inventory policy and an effort-choice strategy that minimize the expected total costs. Our analytical and computational analysis suggests that (i) a state-...

This paper presents an economic production quantity (EPQ) model with a periodic order quantity (POQ) policy, product reliability and periodic demand. The machine reliability has decreased over time; therefore, the rates of perfect and defective products reduce and increase over time, respectively. A fixed percentage of these products are reworked while the rest is wasted. Some equipment in thei...

In this paper we consider a periodic review, reorder point, order-up-to-level system, a type commonly used in practice. Motivated by a specific practical context, we present a novel approach to determining the reorder point and order-up-to-level (for a given review interval) so as to target desired values of i) customer fill rate and ii) average time between consecutive replenishments. Specific...

The cash management of an automated teller machine (ATM) often combines a periodic review inventory policy with emergency orders, the latter according to a continuous review inventory policy. We present a simulation-based decision support system (DSS) that considers both regular (periodic) and emergency (continuous review) orders. This DSS was developed to assist an ATM’s manager in the selecti...

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...

Besides service level and mean physical stock, customer waiting time is an important performance characteristic for an inventory system. In this paper we discuss the calculation of this waiting time in case a periodic review control policy with order-up-to-level S is used and customers arrive according to a Poisson process. For the case of Gamma distributed demand per customer, we obtain (appro...

It is commonly observed that the demand rates of many consumer goods are auto correlated and are dependent on the price and inventory amount. It is believed that the distribution of demand is independent from time to time. But in real life the demand of goods is auto-correlated. The effects of dependency and autocorrelated demand are studied under a periodic review model. An adaptive order-up-t...

R etailers must constantly strive for excellence in operations; extremely narrow profit margins leave little room for waste and inefficiency. This article reports a retailer’s challenge to balance transportation, shelf space, and inventory costs. A retailer sells multiple products with stochastic demand. Trucks are dispatched from a warehouse and arrive at a store with a constant lead time. Eac...