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The EPA is developing a new generation emissions inventory model, MOVES (Motor Vehicle Emissions Simulator). The first version of the model outputs fuel consumption based on available modal data. However, due to the limited heavy-duty vehicle data, MOVES pollutant (CO, HC, NOx) emission rates will need to be supplemented with rates determined with the Physical Emission Rate Estimator (PERE). PERE combines vehicle tractive power together with vehicle powertrain parameters specific to the class of vehicle; the vehicle weight, shape, engine type, and transmission. Analysis of in-use data for heavy-duty diesel tractor-trailer vehicles, city transit diesel buses, and dynamometer non-road diesel engines has enabled a determination of diesel engine friction and indicated efficiency and transmission shift schedules for these engines and vehicles. These model parameters and a comparison of the model results to measured fuel consumption and CO2 emissions are presented.

Highway on-ramp merging is considered as one of the main factors that causes traffic congestion on highways. The drivers along the on-ramp need to adjust vehicle speeds and positions to enter the highway, while the drivers on the highway should also carefully accommodate vehicle speeds and positions to avoid collision with the merging vehicles from the on-ramp, which heavily affects upstream traffic flows. In congested traffic conditions, such maneuvers if inefficiently performed will lead to high risks of accidents and excessive energy consumption and pollutant emissions. In this work, we present an innovative approach to this scenario, where distributed consensus protocol is developed for Connected and Automated Vehicles (CAV) to cooperate with each other by using Vehicle-to-X (V2X) communications.