The Traffic State Identification And Visualizaton Study Of City Road Network

Currently, the urban traffic congestion has become increasingly serious, evolving from a single section or intersection congestion into regional road network congestion. Getting the information of network traffic in time, mastering the network traffic state, selecting the important intersections which has important influence on the operational efficiency of road network and taking priority measures for these intersections can control the impact of congestion in a certain range.As for the traffic state discrimination of road network, this thesis puts forward a prediction model based on Markov process and algorithm of determining intersection importance based on PageRank. At last, it uses the ArcGIS Engine to visualize the traffic information of road network. The main work are as follows:1. Predict the network traffic state using Markov process. By using Markov process and the trait that its state has only something to do with the current state and nothing to do with the past, this thesis takes forecasting analysis towards the traffic state of road network intersections. With reference to the fuzzy comprehensive evaluation method, combining the history state, prediction state and type information of intersection, this thesis makes judgments on road network traffic status and gets the indicators which characterize the overall state of road network.2. The importance ranking of intersection based on PageRank algorithm. PageRank algorithm is applied to web page in the earliest time, and uses the interaction relationship of web pages to judge the importance degree. This thesis puts forward an algorithm of intersection importance ranking based on the traffic flow of road network intersections. The algorithm can select the key intersections in the road network, so that it can control them and relieve the traffic congestion.3. Traffic information visualization system of city road network. Using c# as development language, and ArcGIS Engine as development tool, this thesis designs a set of traffic information visualization system of city road network. The system can visualize the road network traffic information on the map through teechart chart. The system can determine the traffic information of road network in real-time, which is convenient for user to understand the traffic information. At the same time, it has functions of generating map picture and thematic map.