Study On Emergency Evacuation And Rescue Route Based On Dynamic Flow Theory

With the frequently occurred emergencies, emergency management problems have drawn more and more attentions all over the world. In emergency management, however, emergency evacuation and rescue problems in a key position, and which is the main content. Generally speaking, emergency evacuation and rescue can avoid great loss of life and assets effectively, and guarantee the safety of human life and fortune. Emergency evacuation and rescue process indeed involves movement of people by vehicles, which may generate large plenty of traffic trips during limited time. For arranging vehicles orderly rescue and improve the evacuation and rescue efficiency, and vehicles travel must foot set on the road network’s actual condition, and base on actual road network in order to work out an reasonable evacuation and rescue route, which is an important work in the whole process of emergency and rescue.The early study of the evacuation and rescue route adopts the classic network flow model to deal with optimization of the rescue route. This kind of models can offer us convenient, direct solution and reflect the traffic strategy’s influence at the same time. However, there is still some unreasonable points. For example, it can’t reflect the turn delay at intersections. Thus, many scholars have made some modifications of the classic model to reflect the intersection capacity and directional delay. Them reflects the intersection delay and capacity by extending the network, but it is not very reasonable because the network scale becomes lager at the same time. Former scholars’modified model still can’t reflect the real situation clearly when applied in optimizing emergency rescue route. Most of them ignore the variation of time cost and intersection delay when motors running on the road, which leads to the mismatch of the solution to the actual situation.This paper pays attention to these problems mentioned before, namely the variety of time costs in real road and crossing time delay, and takes a further study of optimizing the evacuation and rescue route. By making the actual road network into an abstract directional node-weight network and allocate capacity of intersection and with time-varying the turning delay at intersection with node-weight, then transform the evacuation and rescue route optimization into a directional weight-node network overall maxim flow problem dealt with the improved overall maxim weight-node network flow algorithm. Finally, I make a contrast between solutions including time variety of the turn delay at intersection, time costs on road and without those factors by specific data calculation.