Identifying the Parameters Affecting the Transportation Network in Crisis

Transportation network, under the effect of some external or internal factors, can encounter drop in performance and traffic flow instability. To provide effective parameters and a solution to improve status of the network and to upgrade the qualitative and quantitative situation of network arcs, in the mentioned modes, is a remedial act. In this paper, a hypothetical transportation network is analyzed in terms of the crisis. This hypothetical network includes 52 nodes and 40 arcs. For this network an index will provide in the crisis conditions that specifies averagely how many injured people can be relieved. The index is analyzed by Using Monte Carlo simulation and Daykastra algorithm. In each stage some of the network arcs are assumed to be randomly disconnected; if all path arcs that are connected, the path will be connected and disconnected otherwise. There is an effort to calculate two types of significance coefficient for each arc, which will show its significance over other arcs. Finally, given each one of significance coefficient of arcs, the best paths for connecting relief centers to injured areas are specified, so that after the crisis, it would be clear which paths need more attention and, for example, if it is necessary to have police forces to keep the paths open, these pathsa take priority over other paths. After selecting paths, given each one of significance coefficients, the rate of change in the proposed access index has been calculated, and finally, of two types of significance coefficient, one of them will be applied in specifying relief paths as the more important significance coefficient.