Spatio-temporal Distribution And Environmental Factors Of Urban Traffic Accidents

Nowadays,urban traffic collisions are increasing with rapid urbanization,which brings serious threats to people's lives.The way in which traffic collisions can be effectively prevented has become an urgent problem.In order to improve the level of traffic safety and to ensure sustainable urban development,it is necessary to analyze influencing factors of urban traffic collisions.In view of the problem of urban traffic collisions in China,this study analyzed the occurrence of traffic collisions from the aspects of roads,urban spatial structure and traffic environment.Based on the traffic collision data for the years from 2012 to 2015 in Changning District of Shanghai,this dissertation quantified relationships between environmental factors and traffic collisions.The main contents of this research are as follows:1)Integrating multi-source data to determine environmental factorsBy using GIS to integrate multi-source data,environmental factors of traffic collisions at the micro level,including road structure,urban structure and traffic environment,are determined.In order to obtain large-scale and long-term traffic environmental information,this paper uses a large number of floating car data(FCD)to calculate average speed of vehicles at different time periods,which reflect traffic environment characteristics.2)Identifying hot spots of traffic collisionsIn this study,the entire road network in the study area is divided into several road segments.Spatiotemporal analysis on traffic collisions are performed by segment and intersection.In particular,the network Kernel Density Estimation is adopted to identify traffic hotspots along the road network.3)Quantifying relationships between traffic collisions and potential factorsFollowing spatial and temporal characteristics of urban traffic collisions,this study uses the Negative Binomial Regression(NBR)and Geographically Weighted Poisson Regression(GWPR)models to build quantitative relationship between environmental factors and traffic collisions in four periods.Model results indicated that there are spatio-temporal heterogeneity between environmental factors and traffic collisions.The results of this paper can provide additional information for traffic safety management and smart city planning,which has both economic and social significance.