Queuing problems with fuzzy environment

Abstract

Modelling is sieved through uncertainty. The modern concept of newlineuncertainty was introduced by Prof. Lotfi. A. Zadeh in 1965. Zadeh introduced newlinea theory whose objects fuzzy sets are the sets with boundaries that are not newlineprecise. The membership in a fuzzy set is not a matter of affirmation or denial newlinebut rather a matter of a degree . H.M. Prade discussed an outline of fuzzy or possibilistic models for newlinequeuing system in 1980. In 1989 R.J. Lie and E.S. Lee made a general newlineapproach for queuing system in a fuzzy environment based on Zadeh s newlineextension principle. In 1992, D.S. Negi and E.S. Lee combined the ability of newlinefuzzy sets to represent the queuing system. Buckley investigated multiple newlinechannel queuing system with finite or infinite waiting capacity and calling newlinepopulation. Negi and Lee formulated the á-cut and two variable simulation newlineapproach for analyzing fuzzy queues on the basis of Zadeh s extension newlineprinciple. Kao et al applied (1999) parametric programming to construct the newlinemembership functions of the performance measures for simple fuzzy queues newlinewith one or two fuzzy variable. Schmucker (1984) presented a method for newlinefuzzy risk analysis based on fuzzy number arithmetic operations. Hsieh and newlineChen (1999) presented a similarity measure between fuzzy numbers using newlineGraded Mean Integration Representation method. In 1985 Chen S.H had newlinegiven operations on fuzzy numbers with function principle. newline