Inventory without backorder with fuzzy total cost and fuzzy storing cost defuzzified by centroid and signed distance

In the total cost of inventory without backorders, we fuzzify the total demand r and the cost of storing one unit per day a to the triangular fuzzy numbers (r) over tilde and (a) over tilde in a plan period, respectively. For any order quantity q > 0, we get the fuzzy total cost H-q((r) over tilde, (a) over tilde) in terms of and (a) over tilde. Then we defuzzify by the centroid and the signed distance methods. We can find the minimun total cost and the optimal order quantity by defuzzifying the total cost through the centroid method. We can do the same thing by the signed distance method. Then we compare the results obtained by these two methods. (C) 2003 Elsevier Science B.V. All rights reserved.