A tunable infrared laser differential absorption spectrometer (TILDAS) was used to remotely sense the nitric oxide (NO) emissions from 1,473 on-road vehicles. The real-world measurement precision of this instrument in the limit of low NO concentration is 5 ppm of the vehicle exhaust, which corresponds to a 3o detection limit of 15 ppm. Our analysis of the distribution of negative concentration ...

The Arizona inspection and maintenance (I/M) program provides one of the first opportunities to examine the costs and effectiveness of vehicle emission repair. This paper examines various aspects of emission reductions, fuel economy improvements, and repair costs, drawing data from over 80,000 vehicles that failed the I/M test in Arizona between 1995 and the first half of 1996. We summarize the...

Capacity, demand, and vehicle based emissions reduction strategies are compared for several pollutants employing aggregate US congestion and vehicle fleet condition data. We find that congestion mitigation does not inevitably lead to reduced emissions; the net effect of mitigation depends on the balance of induced travel demand and increased vehicle efficiency that in turn depend on the polluta...

In addition to air pollution emissions, the transportation sector in the US is responsible for more than 25% of greenhouse gas emissions. Due to the negative impacts of these emissions, primarily on health and the environment, literature of vehicle emissions models is rich. Yet, attempts to synthesize and contrast models of this rich literature are scarce. Contrasting models of gasoline and ele...

This study is the first in a series of papers that aim to develop high-resolution emission databases for different anthropogenic sources in China. Here we focus on on-road transportation. Because of the increasing impact of on-road transportation on regional air quality, developing an accurate and high-resolution vehicle emission inventory is important for both the research community and air qu...

On-road vehicle emissions are one of the major sources of transport emissions. As a key design factor, road grades (or road slopes) have significant effects on on-road vehicle emissions, particularly on Heavy-Duty Vehicles (HDVs). However, the research into the relationship between road grades and on-road vehicle emissions is very rare in China. Taking a road network in Taiyuan, China, as a stu...

In the recent years, China's auto industry develops rapidly, thus bringing a series of burdens to society and environment. This paper uses Logistic model to simulate the future trend of China's vehicle population and finds that China's auto industry would come into high speed development time during 2020-2050. Moreover, this paper predicts vehicles' fuel consumption and exhaust emissions (CO, H...

In recent years, great efforts have been made to reduce greenhouse gas emissions by vehicles. Petroleum products produces greenhouse gas emissions, therefore reducing the use of these products can make a major contribution to reducing pollution. The Fleet Size and Mix Vehicle Routing Problem is one of the most widely used routing branches. In this problem, there are vehicle with different capac...

This paper aims to find the efficient state of hybrid electric vehicle (HEV) by simultaneous optimization of the control strategy and the power train. The power transmission employed in this vehicle is a power-split continuously variable transmission (CVT) which uses several fixed ratio mechanisms. After describing this transmission, the rules of electric assist control strategy are introduced....

A mobile laboratory was used to measure onroad vehicle emission ratios during the MCMA-2003 field campaign held during the spring of 2003 in the Mexico City Metropolitan Area (MCMA). The measured emission ratios represent a sample of emissions of in-use vehicles under real world driving conditions for the MCMA. From the relative amounts of NOx and selected VOC’s sampled, the results indicate th...