Research On The Construction Of Inventory Model With Partial-backlogging And Optimization Of Inventory Control Policy

In the new economic era, variance of products, diversity of information and convenience of channels, increase the likelihood of customer lost. Improving customer satisfaction, fostering customer loyalty and reducing the customer loss rate, are one of the most important ways that the retailers develops steadily in the intensely competitive market environment. The native retailers should pay much attention to the influence of partial backlogging on the inventory decisions in order to avoid customer lost in the stock out period. Accordingly, the impact factors and forms of partial backlogging were in depth discussed firstly. Then how to make full use of partial backlogging phenomenon to reduce the rate of customer lost and optimize the retailers'profitability was discussed from the aspects of inventory policy, lead time reduction and price discount.First,based on the hypothesis of time-dependent partial backlogging, the effect of waiting time between the next replenishment and the satisfaction of the backlogging demand on the rate of partial backlogging was investigated in this paper. Then the backlogging rate influenced by the replenishment capacity and the total of backlogging demand was proposed. Based on this new standpoint, an EOQ model of replenishment with the replenishment capacity affecting the partial backlogging was build up. At last, an emulator was performed and the results showed: improving the replenishment capacity could reduce the replenishment times to a lower constant level; this effect may increase the waiting time before the next replenishment, but it could decrease the waiting time after the start of replenishment; so the trend of the lost-sales varying with the replenishment capacity was not very distinct at the medium level of the replenishment capacity; However, the more adequate replenishment capacity could reduce the number of lost-sales and improve the rate of partial backlogging during shortage period than the less one.Secondly, from the aspects of inventory policy, based on the cost structure and customers'sensitivity to the waiting time and the quantity of backlogged items under the stock-out period, the application situation of different replenishment polities was researched according to the cost factors and customers'sensitivity in order to effectively control the quantity of backlogged items under the condition with optimum income. It shows: (s, S) replenishment policy is more suitable to the inventory system with the high unit cost for backlogged items and lost sales; (t, S) replenishment policy and (t, s, S) replenishment policy is more suitable to the inventory system with the high unit cost for backlogged items and lost sales; In the inventory system with the high unit cost for backlogged items and lost sales, (t, S) replenishment policy is more suitable to the inventory system when the customers'sensitivity to the quantity of the backlogged items is lower, or else (t, s, S) replenishment policy is more suitable; and the customers'sensitivity to the waiting time doesn't have a significant effect on the application situation of the replenishment policies.At last, from the aspects of lead time reduction and price discount, based on the hypothesis of time-dependent and price discount-dependent partial backlogging, the backlogging rate influenced by waiting time and price discount was proposed. Extend (r, Q) inventory mode under controllable lead time and time-varying backlogging rate with waiting time and back-order discount was developed and the integrated optimization of the inventory policy, lead time reduction and price discount was discussed in order to effectively control the quantity of backlogged items under the condition with optimum income. Then the impact of lead time decision on total cost, lot-size decision and discount decision was discussed. It shows: lead time reduction decreases total cost conditionally and affects lot-size decision through the fluctuation of lost-sale cost and backlogging cost; if the decreasing of lost-sale cost and backlogging cost is more than the increase of lead time reduction cost, lot-size is decreasing as the reduction of lead time, conversely, it is opposite; lead time decision doesn't influence discount decision directly and the trend of optimal back-order discount varying with the reduction of lead time is consistent with that of lot size.