Traffic Environmental Capacity and MFD Based TrafficEmission Dynamic Control Model

In recent years, the transportation system has become a major source of air pollution. Consequently, it is vital to improve traffic efficiency to preserve urban air quality. Based on the environmental traffic capacity and the macroscopic fundamental diagram theory, the multi-objective programming model is adopted to describe the relationship between traffic emissions and traffic capacity. Then a dynamic traffic volume control method is developed for regional traffic management, which is the feedback gating control method based on the traffic conditions in controlled urban areas. As a case study, the proposed methodology is applied to a road network located in central area of Nanjing. The traffic flow going in and out the study area is controlled by gates via signals to make sure the vehicle amounts and emissions in study area are under the threshold obtained by multi-objective model. The results show that traffic efficiency has improved significantly and that the urban air quality is ensured. This paper can offer some recommendations regarding urban traffic management and air pollution control.