Study On Inventory Models Based On Random Replenishment Intervals

Inventory controlling is an important part of enterprise management. It is advantageous of keeping some inventory, such as keep independence of working procedure in production process, adapting the demand changing, promoting the flexibility of work plan, strengthening the ability to withstand fluctuation of raw market.On the basis of random replenishment intervals inventory model, Paper further presents an inventory model with correlation of demand and selling price and backlogging rate and price discount considerations. It is proved the optimization maybe exist and numerical example demonstrates it. Sensitive analysis indicates that the demand parameters, purchase cost per unit, replenishment intervals'distribution interval and the maximal backlogging rate have different effects on inventory management. In actual work, the retailer should make reasonable maximal inventory level, selling price and price discount decisions with idiographic conditions.A random replenishment intervals inventory model is presented with time-varying demand, stock demand selling rate and taking account of the time-value of costs. Numerical example and sensitive analysis under uniform and exponential distribution indicate the optimal exists and discount rate, deteriorating rate, and stock dependent demand rate have different effects on inventory controlling policy, the uniform one is more sensitive than exponential distribution. The retailer should integrate consider these factors, make scientific inventory control decision.Relaxing the assumption of classical EOQ model of infinite warehouse capability, suppose the inventory system is made up of two warehouse, a own on(OW) and a rented one(RW) with different holding cost and deteriorating rate, a two warehouse inventory model is set up with random replenishment intervals consideration. It is proved the optimal maybe exist and it is demonstrated under uniform distribution. Sensitive analysis indicates that the OW maximal inventory level, deteriorating rate of OW and RW, backlogging rate and replenishment intervals'distribution interval have different effect on inventory expected profits. The retailer should adjust the OW maximal inventory level according to the changes of these parameters to increase the profits level.