Comprehensive Evaluation Of Signalized Intersections Based On Vehicle Emissions

In recent years, as the urban transport system develops, the air pollution caused byvehicle emission has serious effect on people’s life. In order to solve this problem, theemission factor is usually used as an index in traffic evaluation, especially at theintersection.Comprehensive evaluation of a signalized intersection is studied in this paper basedon previous researches. An emission calculation model based on vehicle operationstatus is established which is only used for intersections. Principal component analysisis used to quantify the weights of each index and get the comprehensive evaluationvalue of the intersection. This paper focus on the following aspects:First of all, the existing study about emissions and evaluation of intersection has beensummarized including emission model which is widely used and the influencebetween intersection management control technology and emissions. The mainresearch is comprehensive evaluation method and evaluation index of intersectionswhich can provide the theoretical basis for the further study.Then VSP is used to describe the relationship between vehicle travel condition andemission factors of each pollutant and also the emission factor in each VSP interval isgiven. The emission calculation model based on vehicle operation status is established.It makes traffic micro-simulation model and emissions model working together to getthe emissions of the intersection.Moreover, according to the features of urban signalized intersections and the principleof evaluation indexes, comprehensive evaluation system of a signalized intersection isestablished. PCA is used to reduce the dimensions of the complicated evaluations andmake the remaining principal components uncorrelated, then also to quantify theweight of each of principal component and to comprehensive evaluation value ofintersection.At last, an example is given to show the function of the evaluation model, both of theevaluation value and the sequence results in several intersections. The calculation ofemissions of the intersection through the emission model based on vehicle operationstatus validates the good feasibility and applicability of the model proposed in thispaper. Simultaneous using simulation data of multiple intersections to validate thecomprehensive evaluation model can not only calculate the comprehensive value, but also achieve quantitative comparison among multiple intersections. The modelproposed in this paper has important significance for the evaluation and optimizationof the intersections.