OPTIMIZATION IN FUZZY ECONOMIC ORDER QUANTITY (FEOQ) MODEL WITH PROMOTIONAL EFFORT COST AND UNITS LOST DUE TO DETERIORATION

Background: This model presents a significant model for analyzing the effect of deteriorating items and promotional effort in fuzzy optimal instantaneous replenishment model for finite planning horizon. Accounting for holding cost per unit per unit time and ordering cost per order have traditionally been the case of modeling inventory systems in fuzzy environment. These imprecise parameters defined on a bounded interval on the axis of real numbers and the physical characteristics of stocked items dictate the nature of inventory policies implemented to manage and control in the production system.
Methods: This model postulates the promotional effort cost to frame total inventory cost. Thus a modified fuzzy EOQ (FEOQ) model with promotional effort factor is introduced, it assumes that a percentage of the on-hand inventory is wasted due to deterioration and considered as an enhancement to EOQ model to determine the optimal promotional effort and the replenishment quantity so that the net profit is maximized. In theoretical analysis, the necessary and sufficient conditions of the existence and uniqueness of the optimal solutions are proved and further the concavity of the fuzzy net profit function is established. Computational algorithm using the software LINGO 13.0 version is developed to find the optimal solution.
Results and conclusions: The results of the numerical analysis enable decision-makers to quantify the effect of promotion policy on optimizing the net profit for the retailer and wasting the percentage of on-hand inventory due to deterioration respectively. Finally, sensitivity analyses of the optimal solution with respect the major parameters are also carried out. Furthermore fuzzy decision making is shown to be superior then crisp decision making without promotional effort in terms of profit maximization.