Study Of OD Estimation For Regional Road Network Based On Multi-source Data

Origin-Destination Matrix(OD matrix)is of great significance in presenting traffic characteristic,analyzing trip regularities of residents and forecasting developing trend for the future of road network.Since the presence of estimating OD matrix from traffic counts in 1970 s,there has been a number of studies conducted by scholars.The development of advanced traffic information collection system make it easier to collect accurate link flows,and it is high time to study the OD estimation for regional road network based on multi-source data.Firstly,framework is built for OD estimation of regional road network based on multi-source data,and detailed statements are made for the related theory.Traffic counting location,data fusion and the selection of related theory are as key content for OD estimation.Secondly,with the aim of determining the optimum numbers of location stations and their locations on road network,a method for traffic counting location is proposed based on important degree of links.The microscopic evaluation indicators for links and the macroscopic evaluation indicators for road network are adopted together to calculate link importance based on factor analysis,entropy weighting method and clustering analysis.Thirdly,in order to achieve accurate and effective OD estimation,traffic counts are collected with the information from highway tolling system,electronic police system and continuous traffic count station.Back-Propagation neural network is employed to obtain accurate link observations.Finally,the proposed traffic counting location and link observations collected method are applied to Xiaoshan District.With the purpose of analyzing the effects of the original OD matrix,traffic assignment method,OD estimation procedure and link importance on OD matrix,16 models are set in TransCAD,and the results are analyzed in terms of link flows.Finally,based on entropy weighting,Root Mean Square Error(RMSE%)and relative error(ARE%)of link flows are used as indicators to establish the evaluation criteria Z.The results show that the model which uses Impedance-Gravity Method to obtain original OD matrix,the Stochastic User Equilibrium Assignment as traffic assignment method,the Multi paths matrix estimation as OD estimation procedure and with the consideration of link importance can arrive at the best accuracy.The purpose of this thesis is to provide a reasonable OD estimation method of road network.