The Inventory Problems For Deteriorating Items In Supply Chain Management

As a result of the intensified competiton in the market, supply chain man-agement has attracted many enterprise managers. As an indispensable part, the inventory management plays an important role in supply chain management, so how to develop the optimal inventory policy is particularly important. A classic inventory problem is formulated to obtain the optimal order quantity, the order time and the optimal ordering frequency, with the objective function is to min-imum the total cost or maximum the total profit. Three chapters are included in this thesis.In the first chapter, we describe the research situations of the supply chain management, basic background of the inventory management, some useful infor-mation and the main results obtained in this thesis.In the second chapter, we consider the economic order quantity problem with many deteriorating items taking account of fixed demand. On the condition that demand times and quantities are known already, we analyze the inventory problem with many deteriorating items. The aim is to determine the order times and the order quantities for every deteriorating items, in order to minimize the sum of the all items'ordering costs, holding costs and modification costs. Based on the characters of the optimal solution, dynamic programming algorithm was used to find the optimal ordering policy. At last we show the model and solution procedure by two examples.In the third chapter, we consider the economic order quantity problem for substituting items under loss rate and deteriorating, in which shortages of one deteriorating item may be replenished by the other deteriorating item with the fixed substituting rate in planned horizon. Different items have different deteri- orating rates, and shortages are backlogged partially. In order to maximize the total profit, a purchase-store-sale processes of supply chain model is established to obtain the optimal ordering policy. We prove the existence and uniqueness of the optimal policy and present an algorithm to find the optimal ordering policy, at last we show the model and solution procedure by two examples.