Inventory Transportation Integrated Optimization On Perishable Products

With the advancement of science and technology and the fast change of buyer requirements, the short-life products has been shortened at large, some formerly long-life products gradually turn to perishable products. The ratio of perishable products to modern products is getting higher and higher.The problem of perishable products inventory-transportation integrated optimization is one of the major research areas, which combines operational research and goods-transportation system optimization into a new research branch. This dissertation carries out transportation strategy and inventory-transportation integrated optimization problem, and achieved relevant models, algorithm and application, based on perishable products definition, characteristics and the core of its inventory-transportation integrated optimization, and through the method of quite induction, reasonable supposition, data processing and algorithm design.Because of the perishable products commonly have the obvious characteristics of long advance-produce-period, short sell-cycle, low end-period residual value of unsold products and large demand uncertainty, it` s more difficult to do the research of inventory control and transportation strategy integrated optimization of perishable products than doing the relevant research of durable products. Looking from the demand situation, its undulatory property of the perishable products is big, random. What's more, lacking of reliable historical data makes it more difficult to analysis and forecast its conclusion. Secondly, it's hard to calculate the perishable products deterioration rate and deterioration cost, because of their short-life cycle and complicated deterioration. So, chapter 3 of this dissertation show us the forecast two typical models Computer and Apple products. Finally, in order to lay a foundation for actualizing perishable products inventory-transportation integrated optimization further, the author carries out quantitative analysis and forecast aiming at demand situation of typical perishable products-cellphones and computers in Changsha and gained satisfied results with statistical forecast models.The perishable character of products is rarely considered among the traditional inventory control models, so the application of models is slightly limited as a result of not introducing the product deterioration rate and deterioration cost in the total cost calculation of inventory system. In chapter 4 of this dissertation, the author has improved the perishable products'inventory model of stockout-permission, no stockout-permission, production supplement rate-exsitance, through introducing deterioration rate and deterioration cost, under the condition of linear relationship between presuming demand rate and inventory level. Taking this as a foundation, two kinds of representative perishable products-inventory control models of "Mooncake" product and "Apple" product are established respectively in this dissertation based on the inventory control models which have exponent attenuation rate, inventory control strategy of invisible deteriorating products and physical deteriorating products are achieved, and validity and rationality of models and algorithm are proved with the help of example analysis and comparison. The model has shown the method is effective way of carrying out the perishable products inventory control.The major difference between the perishable products transportation problem and its classical transportation problem is that transportation time is more important in perishable products than in durable products. So, in chapter 5 of the dissertation, the author has studied the models and algorithm of traditional vehicle routing problem and introduced the vehicle route problem with time concept into the perishable products transportation strategy, through discussing transportation characteristics and classification of perishable products. In order to solve the transportation problem of the perishable products, the algorithm optimization of vehicle routing problem is designed through Hopfield neural network. Last, vehicle routing problem has been turned into VRP with time window, and has been settled satisfied by heredity algorithm.Simplex inventory control and transportation strategy are classical problems which are focused on for long time in operational research. There have been relevant models and suitable algorithm to most problems of durable products, but the research of in ventory-transportation integrated optimization problem has just begun. However, it's seldom involved concerning the inventory-transportation integrated optimization problem. In chapter 6, based on the research of traditional durable products inventory-transportation integrated optimization, the author proposes models and algorithm for perishable products inventory-transportation integrated optimization, and also achieved innovation in method with mathematic modeling and introducing deterioration rate and deterioration cost.