This paper studies the competitive and cooperative selection of inventory policies in a two-echelon supply chain with one supplier and N retailers. Stochastic demand is monitored continuously. Retailers incur inventory holding and backorder penalty costs. The supplier incurs holding costs for its inventory and backorder penalty costs for backorders at the retailers. The latter cost reflects the...

In recent years, various researchers have discussed a two warehouse inventory system. This kind of system was first discussed by Hartely (1976) [10]. Hartely presented a basic two-warehouse model, in which the cost of transporting a unit from rented warehouse (RW) to own warehouse (OW) was not considered. Sarma (1983)[20] developed a deterministic inventory model with infinite replenishment rat...

This paper aims to investigate the integrated production/distribution and inventory planning for perishable products with fixed life time in the constant condition of storage throughout a two-echelon supply chain by integrating producers and distributors. This problem arises from real environment in which multi-plant with multi-function lines produce multi-perishable products with fixed life ti...

In this paper we present a model and solution procedures of the Inventory Routing Problem (IRP) encountered in vending machine supply chains working under vendor-managed inventory (VMI) scheme. The new IRP model is built based on the existing Periodic Vehicle Routing Problem with Time-windows (PVRPTW). The model will be referred to as the Integrated Inventory and Periodic Vehicle Routing Proble...

In this paper, we consider a dynamic stochastic inventory model with fixed inventory holding and shortage costs in addition to a fixed ordering cost. WE discuss a sufficient and necessary condition for an (s,S) policy to be optimal in the class of such stochastic inventory models. Furthermore, we explore how such a sufficient and necessary condition can be rewritten when the demand distribution...

This paper proposes the strategy of optimizing constrained multi-item inventory problems under fuzzy environment using a Genetic Algorithm (GA). The GA is used in the sense that it is computationally simple yet powerful in its search for improvement. The typical inventory analysis is sensitive to reasonable errors in the measurement of relevant inventory costs. Therefore the inventory costs are...

In many inventory control contexts, inventory levels are only partially (i.e., not fully) observed. This may be due to non-observation of demand, spoilage, misplacement, or theft of inventory. We study a partially observed inventory system where the demand is not observed, inventory level is noticed when it reaches zero, the unmet demand is lost, and replenishment orders must be decided so as t...

Inventory allocation decisions in a distribution system concern issues such as how much and where stock should be assigned to orders in a supply chain. When the inventory level of an inventory point is lower than the total number of items ordered by lower echelons in the chain, the decision of how many items to allocate to each “competing” order must take into consideration the trade-off betwee...

T his paper studies echelon stock (R, nQ) policies in serial production/inventory systems with stochastic demand. We provide a recursive procedure to compute the steady state echelon inventory levels of the systems, which can be used to evaluate the long-run average holding and backorder costs as well as other performance measures. The procedure is based upon an observation of a relationship be...

When the online stores and the logistics service providers make decision alone, as trade off phenomenon exists, inventory costs achieve the minimum while transportation costs are not the minimum or the opposite situation occurs. When implementing inventory and transportation integrated optimization, the profit of the whole supply chain and the stores increases, while the profit of the logistics...