A Fuzzy Inventory System with Deteriorating Items under Supplier Credits Linked to Ordering Quantity

The inventory problem associated with trade credit is a popular topic in which interest income and interest payments are important issues Most Studies related to trade credit assume that the interest rate is both fixed and predetermined However, in the real market, many factors such as financial policy. monetary policy and inflation, may affect the interest rate Moreover, within the environment of merchandise storage, some distinctive factors arise which ultimately affect the quality of products such as temperature, humidity. and storage equipment Thus, the rate of interest charges, the rate of interest carried, and the deterioration rate in a real inventory problem may be fuzzy In this paper, we deal with these three imprecise parameters in inventory modeling by utilizing the fuzzy set theory We develop the fuzzy inventory model based on Chang et al's [1] model by fuzzifying the rate of interest charges, the rate of interest carried, and the deterioration rate into the triangular fuzzy number Subsequently, we discuss how to determine the optimal ordering policy so that the total relevant inventory cost, in the fuzzy sense, is minimal Furthermore, we show that Chang et al's [1] model (the crisp model) is a special case of our model (the fuzzy model) Finally, numerical examples are provided to illustrate these results