Traffic Operations and Management

An Exploration Of The Market For Traffic Information

Chan, Shirley
Malchow, Matthew
Kanafani, Adib
1997

This report attempts to derive a more accurate economic model to describe the supply and cost mechanisms that influence the market for traffic information. It first gives a history of the traffic information market, its economies-of-scale, and its potential for future development.e history of current The report discusses recent developments of value-added-resellers, the differences that exist in the marketing of their products, and factors influencing their success . Suggestions are presented for commercial broadcast stations and public agencies in terms of maximizing the total benefits of...

Optimal Use of Changeable Message Signs for Displaying Travel Times

Ban, Xuegang (Jeff)
Li, Yuwei
Margulici, Jean-Davi
2009

The report describes the research performed and the findings of the PATH Task Order 6303 “Optimal Use of Changeable Message Signs for Displaying Travel Times”. First, travel time estimation methods from various sources are evaluated against probe vehicle data. Next, a survey of San Francisco Bay Area commuters was undertaken regarding the perception and preference for displaying travel times on CMS. Finally, a model that evaluates the CMS impacts on network traffic and determines optimal CMS configurations was developed and tested. Deployment guidelines for CMS are presented based on these...

Expedited Crash Investigation - With Use of Technologies for Documentation and Processing

Chan, Ching-Yao
Lian, Thang
Ko, Jeff
2007

The mobility and efficiency of California highways are impeded by the recurrent and non-recurrent congestion on a daily basis. Roadway incidents, especially collisions, often result in traffic congestion and travel delays. This project is initiated to explore the use of technologies that will potentially bring direct and immediate benefits to the law enforcement officers and other personnel who are involved in the handling of collision sites and subsequent investigations. The work carried out in this project includes three major components: (1) The experimentation of integrated vehicular...

Freeway Safety as a Function of Traffic Flow: The FITS Tool for Evaluating ATMS Operations

Golob, Thomas F.
Recker, Wilfred W.
Alvarez, Veronica
2002

Understanding the benefits of improved traffic flow (reduced congestion) is critical to the assessment of investments in infrastructure or traffic management and control. Improved flow should lead to reductions in travel time, vehicle emissions, fuel usage, psychological stress on drivers, and improved safety. However, the manner in which safety is improved by smoothing traffic flow is not well understood. The documented research is aimed at shedding light on the complex relationships between traffic flow and traffic accidents (crashes).

Determining the Effectiveness of HOV Lanes

May, Adolf D.
Leiman, Lannon
Billheimer, John
2007

This document is the final report for the two-year PATH Project “Determining the Effectiveness of HOV Lanes”. It has been supported by the California Department of Transportation (Caltrans). The primary objectives of this project have been to evaluate freeways having on-freeway HOV lanes in terms of vehicle-travel, person-travel, occupancy distribution, shape and duration of the peak period, congestion patterns, and air quality both in the HOV lane and the adjacent mixed-flow lanes.Based on a comprehensive literature review an extensive list of reference was developed, along with summaries...

Real-time Density Estimation on Freeway with Loop Detector and Probe Data

Qiu, Tony Z.
Lu, Xiao-Yun
Chow, Andy H. F.
Shladover, Steven
2009

Density, speed and flow are the three critical parameters for traffic analysis. Traffic management and control with high performance require accurate estimation/prediction of distance mean speed and density for large spatial and temporal coverage. Speed, including time mean speed and distance mean speed, and flow estimation are relatively easy to be measured and estimated in the practical site, but accurate density estimation is very difficult. Inductive loop detector systems have been widely deployed, it makes better sense to fully adopt available infrastructure to achieve required...

Improving Operations Using Advanced Surveillance Metrics and Existing Traffic Detectors

Coifman, Benjamin
Varaiya, Pravin
2002

1 OVERVIEW Because travel time provides information over an extended freeway link, rather than at a single point, it is a key parameter for ATIS applications and it is a powerful tool for ATMS. Under PATH sponsorship, we have already developed a prototype travel time measurement system that utilizes existing dual loop speed traps and "model 170" controllers. This research has advanced the work by improving the vehicle reidentification algorithms (Sections 2 and 3) and applying the travel time measurement system over seven freeway links in real-time (Section 4). This latter work was...

SPRINTER Rail: Grade Crossing/Traffic Signal Optimization Study

Wu, Guoyuan
Li, Irene
Zhang, Wei-Bin
Johnston, Scott
Li, Meng
Zhou, Kun
2009

This report investigates impacts to local traffic operations at intersections adjacent to signal preemption by SPRINTER commuter trains and countermeasures that would minimize these impacts. Optimization models have been developed to estimate the waiting queue at the end of the preemption operation and to quickly clear the queue while minimizing overall traffic delay. Based on the optimization models, optimized signal timing plans for a total of 10 intersections were proposed, which are designed to facilitate the clearance of the queue accumulated during the preemption, as well as to...

Improving Performance of Coordinated Signal Control Systems Using Signal and Loop Data

Li, Meng
Zhang, Liping
Song, Myoung Kyun
Wu, Guoyuan
Zhang, Wei-Bin
Zhang, Lihui
Yin, Yafeng
2010

In this project, a traffic data collection system based-on the iDEN wireless network has been developed, lab tested and preliminarily tested in the field. The objective of the system is to provide a cost-effective and easy-to-maintain system that could still reliably provide traffic data over the wireless link.The project team developed an arterial performance measurement method that is based on the signal infrastructure data collected at PT2 Lab, U.C. Berkeley. The performance of the proposed model is illustrated by using a simulation study. The six-signal simulation network covers both...

Field Investigation of Advanced Vehicle Reidentification Techniques and Detector Technologies - Phase 1

Ritchie, Stephen G.
Park, Seri
Oh, Cheol
Sun, Carlos
2002

This report presents the results of Phase I of a multi-year research effort on "Field Investigation of Advanced Vehicle Reidentification Techniques and Detector Technologies," and extends previous PATH research by the authors on MOU 336 "Section-Related Measures of Traffic System Performance: Prototype Field Implementation." The focus of this research included the following: significant expansion and enhancement of the ILD-based vehicle reidentification system at a major signalized intersection in Irvine, California to address reidentification of turning vehicles in addition to through...