Creating of detrimental scenarios for a robust rescue system

The rescue system is represented by few service centers (fire and rescue stations) and many customers (probable locations of first aid or fire), which are some nodes of a transportation network. Service centers were located so that each customer was served from his associated center with respect to the time limit. The unlikely events (excessive snow, black ice, accidents, traffic jams and so on) are increasing the traveling time between the customers and associated centers. In this article we study structure of transport network. We want to find some critical ways (arcs in directed graph) which makes the current (specified) location of centers unusable. Several failures will be modeled by increasing the traveling time simultaneously on multiple ways. This will result not only to an increase of the traveling time between customer and his center, but also to change the route or even change the associated center. An algorithm to find critical ways in transport network for specified service centers locations, based on Paluchs K-shortest path algorithm, will be presented.