For the past twenty years, energy and environmental analysts in the U.S. have been searching for ways to improve urban air quality and make the country less vulnerable to supply and price volatility in the world oil market. To improve urban air quality, the U.S. Environmental Protection Agency...

This paper describes an exercise in estimating the costs and benefits of technology-based fuel economy improvements for automobiles and light trucks. Benefits quantified include vehicle costs, fuel savings, consumers' surplus effects, the effect of reduced weight on vehicle safety, impacts on...

The fundamental diagram, as the graphical representation of the relationships among traffic flow, speed, and density, has been the foundation of traffic flow theory and transportation engineering. Seventy-five years after the seminal Greenshields model, a variety of models have been proposed to...