Research And Development Of Vehicle Exhaust Emission Reduction Technology In Urban Road Under The Support Of GIS

In recent years,the urban air pollution has been commonplace and the motor vehicles have been the major source of air pollution in masses of giant cities.With the constant expansion of urban scale,the increasing improvement of economic standards,the number of vehicles in the city shows a soaring growth,in the meantime,the adverse effects of contaminants emitted by the vehicles on the air pollution have been increasingly serious.Under such circumstances,it's the basic premise to research the exhaust emission characteristics of vehicles and explore its time-space distribution characteristics for controlling vehicle emission contaminants in the city.Moreover,by doing so,a theoretic basis can be provided for urban traffic planning,environmental protection and environmental policy stipulation.The analysis of different emission reduction scenarios will provide the effective scientific basis for solving the problems of urban vehicle pollution.In the first place,it's the antecedent condition to construct the traffic emission model applied for quantitative calculation for further research,furthermore,it's the key for current traffic emission model construction to respond to the emission variations caused by microcosmic changes of traffic characteristics.The traffic emission quantitative model is built up based on the microcosmic changes of traffic characteristics,IVE model,based on the relationships between traffic characteristic data and vehicle emission constructed on the strength of VSP variables,based on the three databases,i.e.basic emission factors,VSP-Bin pollutant-emission rate and real-time traffic-flow data.In the meanwhile,on the basis of Gaussian Diffusion Theory,the Gaussian Line Source Diffusion Model is constructed to build up a model calculation method in line with the actual diffusion conditions of urban vehicle exhaust emission pollution.In the second place,in order to make full use of traffic flow information of other relevant sections in the regional road network,the regional road network short-term traffic flow prediction model(STARIMA)based on time-space dependency is created which is used for predicating the short-term traffic flow in the road network by referring to the road traffic flow historical data of Hangzhou city.Furthermore,the Relation Model of Hangzhou Traffic Flow Characteristics and Emissions constructed based on the contents of Chapter 2 will predict the future traffic pollution conditions of road network in the short term.According to the results,STARIMA model performs well in predication of short-time traffic flow,thus ensuring the accuracy and dynamic of simulation results of vehicle exhaust concentration that is of great scientific significance for mastering the short-term key traffic pollution sections and time in real time and early warning and responding to the traffic pollution countermeasures timely.Moreover,in this paper,I analyze the urban road traffic flow characteristics and spatiotemporal distribution of motor vehicle exhaust concentration,probe into the effects of urban road vehicle countermeasures on air quality improvement based on the research method for motor vehicle exhaust emissions and distribution and law and correlation of distributions among pollutant concentrations in different scenarios of major events and non-major events,which is of important scientific significance and practical to formulate the corresponding joint supporting measures during the major events of government departments in the future.Finally,Hangzhou Vehicle Emission Analysis System structured by C/S is designed and developed based on the road network of Hangzhou,the construction of traffic emission model,exhaust diffusion model and regional road network short-term traffic flow prediction model(STARIMA)based on time-space dependency.The systematic application processes and using effects of Hangzhou Vehicle Emission Analysis System is further demonstrated.In addition,several feasible recommendations for prevention and control of motor vehicle pollution based on the actual conditions of Hangzhou City are put forward.In conclusion,the research has made some breakthroughs in multi-level traffic and environmental data sharing technologies and urban road traffic emission monitoring and forecasting technologies;revealed the law of fast coupling between dynamic traffic operation and vehicle emission;constructed the Traffic Emission Dynamic Measurement Model System under different traffic environment and conditions in the city;developed a Regional Spatiotemporal Distribution Analysis System for Urban Traffic Pollutant Concentration with highly integrated vehicle-source estimation,urban-wide simulation of urban pollutants diffusion and aided decision-making functions;realized the monitoring,forecasting,visual display of daily traffic emissions of urban road network and the traffic emission forecast under different control strategies,thus strongly supporting the odd-and-even license plate rule implemented in Hangzhou and emission reduction joint tests,As well as follow-up major traffic control and other important period of work,etc..The research achievements have provided scientific "prediction table" for urban traffic emission regulation which is positively supporting for improving urban traffic operation and regulatory capacity for emissions as well as of vital significance for realizing the environmental protection and sustainable development of urban traffic system.