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In this study, I examined a two-level supply chain with two-way information exchange in which both the manufacturer and the retailer will be informed of each other’s stock.In order to make use of this type of information exchange, the manufacturer and the retaile modify their single-level base-stock policy to a two-level, state-dependent base-stock policy.Later, I exerted the lost sale policy. And finally, I investigated the impact of this type of information exchange on the general chain criteria. Then, I point out the advantages of this method.
Applying the mentioned method reduces the total cost of system as well as decreasing the average amount of manufacturer’s inventory along with... 

In this paper, we studied a two-echelon inventory system which consists of one central warehouse and one retailer. All installations follow base stock inventory management policy. The customers arrive at retailer according to Poisson distribution. The demand is satisfied when both central warehouse and retailer have positive on-hand inventory. Otherwise, the demand is lost. The lead time of central warehouse and the time needed to replenish orders of retailer are assumed to be exponentially distributed. The purpose of this study is to minimize the expected long-run total cost of the system per unit time. Total cost of the system includes holding costs of central warehouse and retailer, cost... 

This dissertation attempts to develop four inventory control models for two-echelon supply chains. For the all models, the retailers face Poisson demand and lost sales during a stockout. There is also a time-dependent holding cost and a cost per unit of lost sales. However, there is no (or negligible) cost associated with placing an order.
For the first model, we consider a two-echelon inventory system with one central warehouse and a number of retailers. The central warehouse applies (R, Q) policy and retailers apply base stock policy. In this model, we approximate the arrival process of the central warehouse and obtain the total cost of the system, as well as the optimal solution.... 

When demand for a product is price sensitive, pricing and lot sizing decisions are interdependent. Similarly, when a product is highly perishable, the demand may need to be backlogged to avoid costs due to deterioration, i.e., perishability and backlogging are complementary conditions.In this thesis we stablish two economic production quantity models for deteriorating items under conditions of finite production, exponential decay and partial backordering and lost sale. Two joint pricing inventory control models are developed for the problem by employing different modeling approaches over an infinite planning horizon. In two models, customer is viewed to be impatient and the fraction of the... 

This thesis introduces a inventory-routing problem under a vendor managed inventory strategy in a two-echelon supply chain. The VMI Routing problem in this study consists of multiple suppliers, multiple retailers and a single item. The suppliers plan inventory replenishments for retailers based on deterministic demand over multiple planning period. Also they allow stock-outs at retailers, which are considered lostsales. Transshipments are allowed, neither between suppliers nor between customers. Retailers can be supplied just by one assigned supplier. Model also considers some constraints on time and capacity. A mixed integer programming formulation is presented to describe the model. We... 

The thesis has considered a two-echelon supply chain which consists of one central warehouse and multiple retailers. Assume all retailers and the warehouse follow a continuous review inventory model. The costumer’s demand comes to retailers in a Poisson process. The retailers replenish their stocks from the warehouse in an (S-1, S) inventory control policy and the warehouse replenishes its stocks in an (r, Q) inventory control policy from an external supplier with an infinite capacity. It may be more representative to model stockouts as lost sales when the retailers are in a competitive market or in monopoly markets all demand will be backorder. Therefore, if the market situation goes...