Traffic Operations and Management

California System Architecture For Intelligent Transportation: Models For Transportation Systems Management

Hall, Randolph
Thakker, Viral
1998

In 1996, the Federal Highway Administration completed a program to develop a national system architecture (NSA) for intelligent-transportation-systems. This report presents recommendations on methodologies by which system architecture can be used to improve the deployment of transportation management projects, with emphasis on multi-jurisdictional projects. The report is part of a larger project addressing the deployment of an ITS system architecture in California. The project as a whole is led by Claremont Graduate School, and is documented in a separate report.

Supply Side Evaluation of Radio Traffic Information

Yim, Youngbin
Pfeifle, Brian
Hellman, Paul
1997

The study investigated data collection and dissemination processes of radio traffic information in the San Francisco Bay Area. Program directors from thirty two radio stations were interviewed to understand the processes and radio traffic reports were analyzed to evaluate the contents. The study showed that morning traffic conditions were broadcast most frequently. During morning peak hours from 6AM-9AM, the majority of the stations broadcast traffic conditions every 15 minutes. The content of the radio information is limited to traffic flow, incident conditions and transit schedule. The...

Effects of Traffic Density on Communication Requirements for Cooperative Intersection Collision Avoidance Systems (CICAS)

Shladover, Steven E.
2005

Intersection collisions are difficult to mitigate or eliminate by use of ITS technologies for a variety of reasons. These include the complexity of the driving environment and of the driver decision making process at intersections, but also the difficulty of accurately detecting the movements of all potentially conflicting vehicles. Prior research by Calspan-Veridian Engineering (now part of General Dynamics) (1) showed the near impossibility of detecting the relevant information using vehicle-mounted sensor systems. Current research under the IDS program is revealing the challenges...

Some Aspects of the Market for Broadcast Traffic Information

Malchow, Matthew
Kanafani, Adib
1999

In recent years, planners have looked toward traffic information systems as an immediate solution to the congestion on U.S. highways. ITS systems are low-cost relative to many alternatives, and simple implementation allows for quick results. Alongside these investments has been research investigating the use of information systems by drivers and the results to be expected. Many studies have shown that the primary source of information for drivers has been broadcast systems such as the radio (e.g. Yim et al., 1997). Additional research has addressed other media which are used to transmit...

Advanced Simulation Tools for Freeway Corridor Management

Gardes, Yonnel;
Tang, Eric
Ma, Jingtao
May, Adolf D.
2003

As part of the California PATH program, the Paramics microscopic traffic simulation model was applied to the I-580 freeway-arterial corridor. The main purposes of the project were two-fold:- Develop the expertise and transfer the knowledge required in calibrating a large-scale freeway corridor with Paramics;- Prepare a calibrated model for the I-580 corridor that could be used to address operational questions, evaluate potential improvement alternatives and provide input to the decision-making process.In agreement with Caltrans District 4 and Headquarters, the study focused on the...

Estimation of Truck Traffic Volume from Single Loop Detectors Using Lane-to-Lane Speed Correlation

Kwon, Jaimyoung
Varaiya, Pravin
Skabardonis, Alexander
2003

An algorithm for real time estimation of truck traffic in multi-lane freeway is proposed. The algorithm uses data from single loop detectors-the most widely installed surveillance technology for urban freeways in the US. The algorithm works for those freeway locations that have a truck-free lane, and exhibit high lane-to-lane speed correlation. These conditions are met by most urban freeway locations. The algorithm produces real time estimates of the truck traffic volumes at the location. It can also be used to produce alternative estimate of the mean effective vehicle length, which can...

AHSCAP Dynamic Traffic Assignment Program User’s Manual and Design Description

Hongola, Bruce
1996

This research seeks to provide an understanding of the capacity and throughput require- ments of an automated highway system(AHS) via development of a computer model that represents system capacity and demand, operational characteristics, and defined infras- tructure. To do that, a variety of scenarios representing traffic input to the system must be represented. Also, a variety of infrastructures representing different system configurations must be represented. This includes the locations of entrances and exits.Detailed vehicle-based simulations have been used to investigate AHS capacity...

Operations at Regional Traveler Information Centers: The Case of the TravInfo Field Operational Test - Final Results

Miller, Mark A.
Loukakos, Dimitri
2000

TravInfo is a regional traveler information system in the San Francisco Bay Area. It was a Field Operational Test (FOT) over a two-year period from September 1996 to September 1998 with funding from the Federal Highway Administration and the California Department of Transportation (Caltrans). TravInfo's goal was to broadly disseminate accurate, comprehensive, timely, and reliable information on traffic conditions and multi-modal travel options to the public in the Bay Area. Organizationally, it was structured around a collaborative partnership between and among public and private...

A Methodology for Developing a Traffic Surveillance Investment Program: An Application to Caltrans District 4

Dahlgren, Joy
2000

A method for determining how to develop the most effective traffic surveillance investment program given available resources is developed. The complicated decision structure for deciding where and when to install traffic surveillance and what type of surveillance to install is broken down into a series of steps: identifying information needs, determining which can be met by traffic surveillance, setting criteria for and evaluating the benefits of surveillance in various locations, identifying alternative surveillance methods and estimating their capabilities and costs, comparing the ratios...

Short Term Freeway Traffic Flow Prediction Using Genetically-Optimized Time-Delay-Based Neural Networks

Abdulhai, Baher
Porwal, Himanshu
Recker, Will
1999

Proper prediction of traffic flow parameters is an essential component of any proactive traffic control system and one of the pillars of advanced management of dynamic traffic networks. In this paper, we present a new short term traffic flow prediction system based on an advanced Time Delay Neural Network (TDNN) model, the structure of which is optimized using a Genetic Algorithm (GA). After presentation of the model's development, its performance is validated using both simulated and real traffic flow data obtained from the California Testbed in Orange County, California. The model...