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BTS (version 1.0): Bottleneck Traffic Simulator User's Manual

Lin, Wei Hua
Hall, Ranolph W.
1991

Describes the computer program BTS which is a macroscopic tool for simulating the performance of freeway bottlenecks

Freeway Performance Measurement System: Final Report

Varaiya, Pravin
2001

PeMS is a freeway performance measurement system for all of California. It processes 2GB/day of 30-second loop detector data in real time to produce useful information. Managers at any time can have a uniform and comprehensive assessment of freeway performance. Traffic engineers can base their operational decisions on knowledge of the current state of the freeway network. Planners can determine whether congestion bottlenecks can be alleviated by improving operations or by minor capital improvements. Travelers can obtain the current shortest route and travel time estimates. Researchers can...

Safety and Efficiency Tradeoff Analysis for Automated Highway System: Part 3: Longitudinal Separation on AHS: A Trade-off Between Collision Probability/Severity and Capacity

Tsao, H.-S. Jacob
Hall, Randolph W.
1997

This report develops a probabilistic model for analyzing longitudinal collision/safety between an abruptly decelerating vehicle and its immediate follower on an Automated Highway System. The input parameters are the distance between the two vehicles, their common speed prior to the failure, the reaction delay of the following vehicle and a bivariate distribution for the two deceleration rates. The output includes the probability of a collision and the probability distribution of the relative speed at collision time. These safety consequences can be used to balance the desire to increase...

Modeling of the Brake Line Pressure to Tire Brake Force Subsystem

Xu, Z.
Ioannou, P.
1994

One of the most challenging problems in automated vehicle control is when and how to apply the brakes. In order to deal with such a problem, a good understanding of the dynamical behavior of the braking mechanism is essential. In this report we use experimental data from a series of tests performed in collaboration with Ford research engineers to modelthe brake line pressure to tire brake force subsystem. This model will be used together with that of the master cylinder to line pressure currently under study, for developing an overall model for the braking mechanism. The brake model will...

A Conceptual Approach for Developing and Analyzing Alternate Evolutionary Deployment Strategies for Intelligent Vehicle/Highway Systems

Al-Ayat, Rokaya
Hall, Randolph
1994

Intelligent Vehicle Highway Systems (IVHS) comprise a spectrum of technologies, with both short - term and long - term applications. Eventually, deployment of IVHS may lead to fully automated, hands-off and feet-off, driving. In the short - term, IVHS has included traffic control systems, in - vehicle information systems, and a range of new roadway sensors.This paper develops a framework for planning the evolutionary deployment of IVHS technologies. It defines an evolutionary deployment sequence, identifies baseline assumptions, and presents strategies for achieving success. This paper...

Evaluation Of Work Crew And Highway Hazard Conspicuity

Misener, Jim
1998

The report quantitatively addresses conspicuity of highway features, particularly in work zones, from the perspective of driver detection and driver decision making. The study focuses on evaluating the detection process, selecting and exercising human perception-acquisition models suitable for quick running and larger scale microsimulations to evaluate system effectiveness of pre-Automated Highway System (AHS) driver-assist systems. The report describes this process and provides a detection example of a driver-assist collision avoidance model.

TravInfo Evaluation: Traveler Response Element; TravInfo 817-1717 Caller Study; Phase 2 Results

Koo, Ronald
Yim, Y. B.
2001

TravInfo was a federally funded Field Operational Test (FOT) of the Advanced Traveler Information System (ATIS) in the San Francisco Bay Area. The general public can obtain most current traveler information through TravInfo's Traveler Advisory Telephone System (TATS) and privately offered information services including traffic Web sites. As part of the TravInfo FOT Evaluation, two waves of TATS callers were surveyed. The first wave of the TATS caller survey was conducted in April 1997. The second wave TATS caller survey was completed in April 1999. This paper presents the findings of the...

A Comparable Systems Analysis Of San Francisco's BART: Lessons For Automated Highway Systems

Hickman, Mark D.
1994

This study examines the lessons to be learned from the experience of the San Francisco Bay Area Rapid Transit (BART) system, particularly as applied to the growing research on automated highway systems (AHS). The first section of the report briefly motivates the analogy of BART by comparing some of the technical and non-technical performance factors surrounding both AHS and BART. Several pertinent technical and non- technical issues surrounding BART are described in more detail, emphasizing the decision-making that went in to BART's development, testing, and the beginning of revenue...

Consumer Research on Advanced Traveler Information Systems: TravInfo Field Operational Test

Yim, Youngbin
1997

The paper describes the evaluation framework of the TravInfo project, a field operational test of the San Francisco Bay Area advanced traveler information system. The purpose of the evaluation study is to measure changes in individual travel patterns that result from the TravInfo project and to assess traveler acceptance of and preference for advanced traveler information technology. The anticipated effects of TravInfo on Bay Area travelers were described using some of the economic concepts of supply and demand relationships between information providers and information users. Consumer...

A Network Layer for Intelligent Vehicle Highway Systems

Eskafi, Farokh
Zandonadi, Marco
1999

The objective of this paper is to design the network layer of a communication stack to be used in Automated Highway Systems (AHS). The communication model we propose allows cars to form private subnets, the configuration of which can change dynamically. Each car be part of multiple subnets and can send broadcast, multicast and point-to-point messages to other vehicles (both on the same subnet and on others, through a routing mechanism). Each subnet is managed by a server: a car that is in charge of accepting/rejecting join requests and of keeping a consistent state within the subnet....