THE FUZZY SHORTEST-PATH PROBLEM AND ITS MOST VITAL ARCS

The shortest path problem is to find the shortest distance between two specified nodes in a network. An arc is called a single most vital arc in the network, if its removal from the network results in the greatest increase in the shortest distance. The availability of arcs plays a key role in network problems. The most vital arcs problems provide a means by which the importance of arc's availability can be measured. In the traditional shortest path problem, the arc lengths are assumed to be crisp numbers. In this paper, we consider the case that the arc lengths are fuzzy numbers. In particular, we derive the membership function of the shortest distance by using a fuzzy linear programming approach. Based on this result, we then propose an algorithm for finding the single most vital arc in a network.