Bottlenecks are key features of any freeway system. Their impacts are of increasing importance as congestion worsens in major urban areas. In the U.S., the FHWA has been working to identify and monitor key bottlenecks in each state. In Oregon, a freeway data archive known as PORTAL records count, occupancy, and speed measurements from over 600 freeway locations. This archive has enabled develop...

15. Supplementary Notes Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration. 16. Abstract Traffic congestion is an increasing problem in the nation’s urban areas, leading to personal inconvenience, increased pollution, hampered economic productivity, and reduced quality of life. While traffic congestion tends to continuously increa...

Real-data testing results of a real-time nonlinear freeway traffic state estimator are presented with a particular focus on its adaptive features. The pursued general approach to the real-time adaptive estimation of complete traffic state in freeway stretches or networks is based on stochastic nonlinear macroscopic traffic flow modeling and extended Kalman filtering. One major innovative aspect...

This study presents a surrogate safety measure for evaluating the rear-end collision risk related to kinematic waves near freeway recurrent bottlenecks using aggregated traffic data from ordinary loop detectors. The attributes of kinematic waves that accompany rear-end collisions and the traffic conditions at detector stations spanning the collision locations were examined to develop the rear-e...

Title of Document: UNDERSTANDING THE IMPACT OF INCIDENTS AND INCIDENT MANAGEMENT PROGRAMS ON FREEWAY MOBILITY AND SAFETY Chih-Sheng Chou, Doctor of Philosophy, 2010 Directed By: Associate Professor, Elise Miller-Hooks, Department of Civil and Environmental Engineering Despite significant technological achievements over past decades, and institutional support for Intelligent Transportation Syste...

The paper begins with a brief discussion of issues that must be resolved in building a freeway data management system. Following this is a description of the design choices that dealt with these issues in a functioning system for California freeways. The system is called PeMS. Some concrete uses of PeMS are presented next. These uses imposed the functional requirements that led to the design ch...

The primary objectives of this study were to use variable speed limits (VSL) upstream freeway lane drop maintain capacity and reduce congestion. As driving behaviours are the main reasons leading microscopic simulation can reflect precisely, simulations first used test scenarios. objective function constraints determined according traffic engineering practice optimised using a modified genetic ...

............................................................................................................................. iii Acknowledgments............................................................................................................... v Dedication .......................................................................................................................... vi T...

Recently, there has been a significant amount of research related to heavy trucks operating as connected and autonomous vehicles (CAVs). As argued in this paper, understand the potential impact on freeway system CAV technologies, analyses should be conducted using standard US methodological framework. Consequently, paper uses exact Highway Capacity Manual, Sixth Edition (HCM-6) equal capacity p...