An Integrated Partial Backlogging Inventory Model having Weibull Demand and Variable Deterioration rate with the Effect of Trade Credit

Demand considered in most of the classical inventory models is constant, while in most of the practical cases the demand changes with time. In this article, an inventory model is developed with time dependent two parameter weibull demand rate whose deterioration rate increases with time. Each cycle has shortages, which have been partially backlogged to suit present day competition in the market. Also the effect of permissible delay is also incorporated in this study. The total cost consists of ordering cost, inventory holding cost, shortage / backordering cost, lost sale cost and deterioration cost are formulated as an optimal control problem using trade credit policy. Optimal solution for the model is derived and the trade credit on the optimal replenishment policy are studied with the help of numerical examples.