Abstract: In this paper, we introduce the fuzzy concept for reverse reneging which helps to find the expected system size (LS) in terms of crisp value for a finite capacity single server queuing system. By considering the arrival rate, service rate and the reneging rate as trapezoidal fuzzy numbers, we convert all these fuzzy numbers into crisp values by using Robust Ranking Technique. Further we use this technique to find the expected system size. Finally, the analytical results are numerically verified by changing the values for different parameters under crisp environment for LS.

Keywords: Reverse Reneging, Queuing Systems, Robust Ranking Technique, Fuzzy numbers and Crisp values.