An Optimizing Strategy Of Traffic Signal Controlling Based On The Route Of Key Flow

The increasing transportation needs have led to severer urban traffic jams.In many large and medium-sized cities,their transportation infrastructure has relatively matured,and the traffic jam can be relieved through appropriate traffic controls.Traffic signal control enables vehicles to gain access to way-leave in a reasonable time length.Moreover,optimization of signal timing is a main way to improve traffic signal control effects.The article researches optimizing strategy of key-flow-based traffic signal controlling.First of all,the article puts forward to the definition of key flows: key flows are the flows that inflicting the greatest impact on the traffic both in the spatial and time senses.Appropriate management of key flows can effectively relieve traffic jams.Besides,three types of key flows will be given weight for the analysis,namely key flows at the road-crossing,key flows on certain road sections,and key flows along certain routes.After analyzing the saturation and growth features of vehicle flows,the article puts forward concrete identification methods of different key flows and corresponding signal controlling strategies.RFID is adopted as the major data collecting technique in the article.A traffic signal controlling system is designed based on RFID technology after studying its composition,features,application in transportation,as well as relevant theories and technologies making it work.As a verification on the optimizing method,the author selects several representative study samples in Nanjing.The collected data is further processed as simulation and verification by using transportation simulation software VISSIM.The simulation result shows that the method of key-flow-based traffic signal controlling can effectively reduce the delay of road traffic flow and the number of stops,thus essentially improving the passing efficiency of traffic flows.