Traffic Signal Control Of Urban Intersection Case Of Emergency

Signal control of urban traffic has been a widely concerned problem for a long timebetween big to urban planning and small to citizens to travel, in particular, under emergencycases, the traffic control was quite important. In recent years, the number of sudden events incit was constantly increased, such as "5.12wenchuan earthquake" and similar specialcircumstances occur. During the emergency evacuation and emergency relief, there’s nodoubt that to reduce the depth of damage and even death due to without timely rescue makesure the personnel safe places or the medical facilities as soon as possible. In general, thevehicle evacuation and rescue vehicles were collectively referred to as emergency vehicles.Besides, due to the urgent emergency vehicles, the patients usually need to be sent to rescuesites or medical facilities as soon as possible. However, it was a common phenomenon thattraffic congestion might make it harder for emergency vehicles to reach their destinationsafely. What’s more, the operation of the emergency vehicle could further aggravate trafficjams, and even cause new accidents. Therefore, to guarantee the steady of the emergencyvehicle run, two levels were obeyed, the first was the network level, the quickest routebetween its task was to determine the end point, which could make emergency vehicles arriveas soon as possible along the route. The second was the intersection of its requirement was toassure the safety of vehicles across the intersection quickly. Although network level was tofind the shortest route in relatively easy way, the current study was focused on the intersectionsignal control. So this study made some analysis about the emergency cases city intersectionsignal control.First of all, in view of the research at home and abroad, draw lessons from experience tofind out the ways to solve this topic model by analysis of intersection control models andmethods and to find out the reasonable traffic model, considering the current traffic situationof emergency situations. And by combining with the analysis of traditional signal control andmodern control technology, the concept of hybrid Petri net model control is given. Secondly,the emergency situation, emergency vehicles and emergency traffic made some theoreticalresearch ignoring emergency situation analysis of the intersection delay. Theoretical analysisof the definition of the problem was more targeted, at the same time, it was clear foremergency vehicles limited by the condition of signal intersection, and the general urbantraffic system intersection signal delay was investigated through the analysis of the vehicle.Besides, the emergency cases city hybrid Petri nets model of signal intersection wereestablished. Petri net model, the establishment of urban intersection signal hybrid Petri netmodel and the emergency cases intersection signal control Petri model made a detail analysis.Finally, the genetic model for calculus and computer software Matlab simulation (R2009a) were applied. Priority control strategy was put forward and the intersection of emergencycases signal with Petri net model without considering the emergency situation of signalcontrol delay for comparative analysis.