Deterministic Lot-size Models For Deteriorating Items With Piecewise Type Demand Rate

Global market provides more sales opportunities for the growing department store retailers,but also poses new challenges to inventory management.With the rapid development of science and technology and the rapidly changing demand conditions of customers,the life cycle of most commodities has been shortened,which also makes deteriorating items hold an increasing proportion in today's consumer market.Deteriorating items have the characteristics of perishable,obsolescence,short sales cycle and large demand uncertainty.This also means that the perishability of deteriorating goods will make inventory management more difficult for retailers downstream of the supply chain,and bring challenges to the daily operation of retailers.Therefore,it is of great significance to study the inventory of perishable commodities for regulating the supply and demand of deteriorating items in the consumer market.From the existing research review in the field of inventory management,the research on non-deteriorating items is far more than the related research on deteriorating items in terms of breadth and depth,and the effect of inventory optimization research on deteriorating items in practical application is not ideal.Taking deteriorating items as the research object,this paper discusses the inventory optimization of perishable goods in retailers.At the same time,based on reading a lot of literature on perishable goods and learning the theoretical knowledge of inventory optimization in retail,this paper puts forward the problem of retailer's lot-size inventory management on deteriorating items.With five chapters,firstly,the main literature in the field of deteriorating items research is reviewed and summarized.Then,the significance and importance of the research on the lot-size inventory of deteriorating items are understood.Then,the optimization of retailer's total inventory cost is determined as the research objective of this paper,and the inventory optimization of deteriorating items is realized by using retailer's cost control.From the summary and analysis of the literature,we know that the life cycle of deteriorating items is limited,so they are more sensitive to time.In order to better reflect the characteristics of deteriorating items in the construction model and make the research more practical,this paper introduces a piecewise type demand function,that is,demand rate is a piecewise type function: demand for deteriorating items rises linearly first,then tends to be stable.At the same time,stock shortage is allowed,and the stock shortage part is overstocked at a rate of non-linear change with waiting time.Then,according to the single inventory cycle,two inventory cycles and multiple inventory cycles,three batch inventory models of deteriorating items are constructed,and it is proved that the total inventory cost of retailers is a convex function of the time of shortage and replenishment.Then a numerical example is given to provide suggestions on inventory management for retailers,and the parameters of the model are analyzed numerically to find out the variables that have a greater impact on the optimization of the total inventory cost of deteriorating items for retailers.The last section is about the summary of this paper and the future research direction.This paper focuses on the problem of lot-size inventory management of deteriorating items,and studies the optimal inventory strategy under the condition of allowable inventory shortage.