Application of Fuzzy Ranking Method to Determine the Replacement Time for Fuzzy Replacement Problem

In every field of our real life situations, we deal with a replacement problem, when some items such as machines, medical equipment, military tank, electric bulb etc. or workers need to replace due to their decreased efficiency, failure or break down. To get a more realistic view of a replacement problem, here, we consider that the capital cost ( C ~ ), scrap value or resale value ( S ~ ), maintenance cost or running cost ( t f ~ ) are all of fuzzy numbers. These fuzzy numbers are considered as a trapezoidal fuzzy numbers or triangular fuzzy numbers. Yager’s Ranking method (1981) has been used to determine the best alternative of fuzzy numbers. It has been also used to transform a replacement model with fuzzy cost to a replacement model with crisp cost. Then we solved it by any conventional method. Two numerical examples have been solved to show the effectiveness of the proposed method. General Terms Fuzzy Replacement Problem.