TWO-STORAGE FUZZY INVENTORY MODEL WITH TIME DEPENDENT DEMAND AND HOLDING COST UNDER ACCEPTABLE DELAY IN PAYMENT

If we observe a real business market, the demand for items in each cycle is not in the same pattern, that is, for specific business cycle it may increase, stable or decrease (for instance, cool drinks from end stage of the summer to winter; the demand goes on decreasing, and from the end of winter to peak time of summer; the demand goes on increasing). Also, if the supplier permits for delay in payment, retailer wishes to buy more goods, and for which the retailer may need extra storage (in terms of a rented warehouse). Moreover, the retailer has always wished to sell the items before they expire and accordingly order is placed. Mostly the parameters in a real world inventory model are imprecise. Thus, in the proposed study an inventory model having decreasing time dependent demand pattern with variable holding cost for TwoStorage facility under acceptable delay in payment has been developed. Mathematical model of the problem and its solution procedure is discussed for both crisp and fuzzy environment in order to obtain the optimal replenishment time and cost. Also, numerical examples are discussed to validate the study. Finally, sensitivity analysis is also studied to describe the fluctuating scenario of associated parameters.

Effect of Inflation and Variable Holding Cost on Life Time Inventory Model with Multi Variable Demand and Lost Sales

This paper analyses an inventory model for life time declining item with variable carrying rate and multi variable demand rate. In this model, the consumption rate depending on selling price as well as displayed stock and when the shortage occurs only on selling price of the manufactured article. Moreover, in this model the deterioration is taken time dependent, which is non-instantaneous in nature. In this study we also consider a very realistic concept of variable carrying rate in which the carrying rate per unit per period to be a function of the time used up in storage. This model is firm for minimizing the average total rate per unit period under the effect of inflation and time value of money. Numerical examples are used to illustrate the wished-for model and a sensitivity analysis is passed out to study the effect of different constraints