Research On Location Of Variable Message Sign

Urban traffic conditions are increasingly severe.Intelligent transportation systems are an important direction for solving urban traffic problems.With the development of science technology and the tendency of national policy dividends for intelligent transportation,intelligent transportation has picked up the banner of leading the modernization of transportation.it's the one of the major trends to future development of transportation in the future.As a branch of the intelligent traffic system,the variable message sign is an important tool for traffic induction.The location selection of variable message sign has a positive effect on traffic induction and mitigation of traffic congestion.Unreasonable selection of variable message sign will result in duplication of sign information content.The inductive effect is not good,and the reasonable selection of variable message signs can effectively allocate road traffic flow and relieve urban road congestion.Therefore,it is very meaningful to study the problem of variable message sign location.For the issue of variable message sign location,the following aspects were studied:(1)Researched the traffic guidance system,elaborated the meaning of the trafficinduced system,described the development of the traffic guidance system and the release mode of the traffic guidance system,and cleared that changeable information signs are one of the most important information-release methods of the traffic guidance systems.A general overview of the variable message signs was conducted.The contents,types,and distribution methods of the general variable message signs were studied.The function of the variable message signs in the road network was clarified.Based on the variable information-inducing function,the location principle,influencing factors and objectives of the variable message signs are analyzed.(2)Starting from the complex network theory,we will focus on the evaluation of key nodes in complex networks and express the road network in a complex network.The node degrees,node inequalities,and node weights are used as the evaluation criteria of the key nodes under the influence of VMS site selection.The key points of the road network are identified with the Grey Relational Analysis,and the initial location of the VMS network is selected with the surrounding road sections of the key nodes.(3)Study on Location Selection of VMS Road Network from the Perspective of Traffic Assignment.The Probit model was established based on perceived travel time as the basis for traffic allocation,and the installation location of VMS was the constraint condition,and make use of the Monte carlo simulation algorithm(Monte carlo)for traffic allocation to obtain traffic distribution of road network corresponding to VMS installed at different locations.(4)The location of VMS in the road section and the influencing factors of VMS installation in the road section were analyzed.What's more,the driver's response to the VMS logo was established.Combined with the VMS's own structure,the value range of the VMS installed on the road section was obtained.(5)Taking a regional road network in Chongqing as the research object to calculate the location of the road network and road sections for VMS.