Linking On-Road Emissions with Traffic Flow Variations

Principal Investigator(s):

Henry Liu, Former Professor, Civil, Environmental and Geo-Engineering


  • Julian Marshall, Former Assistant Professor, Civil, Environmental and Geo-Engineering

Project summary:

This research proposes to develop a real-time shortest path algorithm that will link traffic flow characteristics and on-road emissions. The shortest path problem is quite important in the transportation field, but limited research has taken into consideration intersection delays and increased vehicle emissions caused by traffic signals. When considered, the traffic signal was mostly modeled as fixed timing. Delays and vehicle emission increases caused by queuing vehicles were rarely considered. Consequently, the shortest path problem considering traffic signals is usually deterministic. In the case of actuated traffic signal control, however, the intersection delays are stochastic in nature. In addition, the delays experienced by a vehicle at a downstream intersection may depend on the delays it experiences at upstream intersections. For this project, the researchers will develop a shortest path algorithm that will consider intersection traffic dynamics. The objective of the shortest path search is to reduce fuel consumption and vehicle emissions by considering en-route traffic flow characteristics. The output of the algorithm will be an optimal policy rather than a single optimal path. The researchers will show that the required input information for the model can be estimated from high-resolution traffic data obtained from the field, and numerical tests will be carried out.

Project details:

  • Project number: 2013043
  • Start date: 07/2012
  • Project status: Completed
  • Research area: Transportation Safety and Traffic Flow
  • Topics: Data and modeling