Environment

Traffic congestion has become an increasingly critical issue across the United States, disrupting transportation networks and impacting society in ways that extend beyond mobility. Congestion contributes to declining public health, reduced quality of life, and environmental concerns such as pollution, noise, and stress (Meyer, 1997). Nationally, travel delays rose from 5.1 billion hours in 2000 to 8.7 billion hours in 2019, while fuel waste increased from 2.4 billion gallons to 3.5 billion gallons over the same period. Similarly, excess greenhouse gas emissions escalated from 25 million...

This report documents the findings of research sponsored by the Los Angeles World Airports to examine the influence of airport capacity constraints on airline fleet mix and to explore the potential effects of policy options to influence airlines to use larger aircraft types and thereby accommodate growth in passenger or cargo demand without a corresponding increase in the number of aircraft operations. This issue is of growing importance at many major airports in the United States and indeed around the world, as a steadily increasing demand for air transportation has resulted in volumes of...

Fire spread models (FSMs) are used to reproduce fire behavior and can simulate fire propagation over landscapes. As wildfires have emerged into a global phenomenon with far-reaching impacts on the natural and built environments, FSM simulations provide crucial information to better understand and predict fire behavior in various landscapes. In this study, we tested Cell2Fire, a recently developed cellular automata-based FSM, against benchmarking models used in the U.S., Canada, and Chile. We experimented on synthetically generated landscapes (homogeneous and heterogeneous mix of fuels),...

Cooperative Adaptive Cruise Control (CACC) is a term that has been used rather loosely in recent years, such that different people visualize different functions and capabilities when discussing CACC systems. Thus, there are now multiple system concepts that have been described under the CACC label, and the functionalities included in these varied concepts can be quite different from each other. At the heart of each CACC concept is the merging of Adaptive Cruise Control (ACC), a subset of the broader class of automated speed control systems, with acooperative element, such a Vehicle-to-...