Traffic Operations and Management

Commuters' Normal and Shift Decisions in Unexpected Congestion: Pre-trip Response to Advanced Traveler Information Systems

Khattak, Asad
Polydoropoulou, Amalia
Ben-akiva, Moshe
1996

This report presents a study whose objective is to explore how people deal with unexpected congestion during the pre-trip stage and how they might respond to Advanced Traveler Information Systems (ATIS). Travelers' route, departure time and mode selection decisions were investigated through a survey of San Francisco Bay Area automobile commuters. The effects of various factors are examined, such as sources of congestion information, trip characteristics, and route attributes. The pre-trip response to future ATIS technologies is explored through stated preferences.

Commuter Response to Traffic Information on an Incident

Koo, Ronald
Yim, Youngbin
1998

This paper presents and discusses how traffic information is obtained and how it affects travel behavior when a major freeway is congested. Immediately following a major highway incident south of San Francisco which caused congestion, a telephone survey was conducted of commuters who utilize the affected corridor of highway. The behavior of commuters before and during their commute at the time of the incident was determined, including obtaining traffic information and how the information influenced changes in route, mode of travel and departure time. The results of the survey suggest that...

Collision Analysis of Vehicle Following Operations by Two-dimensional Simulation Model: Part I - Effects of Operational Variables

Chan, Ching-Yao
1997

This research project investigates the behaviors of vehicles in collisions, especially when they are closely spaced. The study uses a two- dimensional simulation program, EDSMAC, which allows longitudinal and lateral movements as well as the yaw motion of vehicles. The simulation model calculates impact forces in collisions and estimates the resulting vehicle damage. Collision situations are simulated. The subsequent post- impact vehicle trajectories are then analyzed. By varying parameters in simulation cases, one can evaluate the potential effects of such variables in vehicle-following...

CIRCLES: Congestion Impacts Reduction via CAV-in-the-Loop Lagrangian Energy Smoothing

Bayen, Alexandre M.
Lee, Jonathan W.
Piccoli, Benedetto
Seibold, Benjamin
Sprinkle, Jonathan M.
Work, Daniel B.
2024

The energy efficiency of today’s vehicular mobility relies on the un-integrated combination of i) control via static assets (traffic lights, metering, variable speed limits, etc.); and ii) onboard vehicle automation (adaptive cruise control (ACC), ecodriving, etc.). These two families of control were not co-designed and are not engineered to work in coordination. Recent studies have shown i) limitations of controls, and even ii) negative impacts of ACC. This project focused on the technology development, implementation and prototyping, and validation of Mobile Traffic Control (MTC). MTC...

Assess the Trade-Offs Between People Through-Put and Level of Service Degradation in the Conversion of a Mixed Flow Lane to a Bus Only Lane on US 101

Li, Yue Irene
Li, Jing-Quan
Miller, Mark A.
Zhang, Wei-Bin
2001

This report proposes a generalized process for evaluating the ridership impact and traffic impact of a bus rapid transit system. The process proposed aims at providing such evaluation at the sketch planning stage and has a specific focus on two aspects -- the ridership forecast based on the implementation of various ITS technologies and the degradation of level of service that results from converting a traffic lane into exclusive bus lane for the implementation of a bus rapid transit system. The proposed process is tested on the Van Ness Blvd site in San Francisco, California. It is also...

An Investigation of the Costs of Roadway Traffic Congestion: A Preparatory Step for IVHS Benefit's Evaluation

Miller, Mark A.
Li, Kayin
1994

This report focuses on traffic congestion under current road conditions with the objective of developing a quantitative understanding of their costs. The work is intended to provide a foundation upon which to build later estimates of the benefits that could be attributable to the use of Intelligent Vehicle Highway Systems (IVHS) technologies. The report gives an overview of traffic congestion and summarizes the principal sources of research in the areas of quantifying the costs of congestion. It reviews this past work relative to the usage of data, methodological approaches used in the...

An Integrated Physical/Link-Access Layer Model of Packet Radio Architectures

Polydoros, Andreas
1994

The goal of this effort is to devise and analyze an integrated Physical/ Link-Access Layer Model of packet Radio Architectures, with application to the PATH/IVHS (Intelligent Vehicle Highway Systems) communication sub- system design between vehicles and infrastructure, as well as between vehicles on the move. The present report contributes to a generic conceptual model for system evaluation which can be used for quantification of the interaction between network layers. The research tasks that have been performed for achieving the project objectives include collection of data requirements...

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...

Adaptive Throttle Control for Speed Tracking

Xu, Z.
Ioannou, P.
1994

In this paper, the authors design an adaptive control scheme for electronic throttle that achieves good tracking of arbitrary constant speed commands in the presence of unknown disturbances. The design is based on a simplified linear vehicle model which is derived from a validated nonlinear one. The designed control scheme is simulated using the validated full order nonlinear vehicle model and tested on an actual vehicle. The simulation and vehicle test results are included in this paper to show the performance of the controller. Due to the learning capability of the adaptive control...

Adaptive Signal Control System with On-line Performance Measure for Single Intersection

Liu, Henry X.
Oh, Jun-Seok
Recker, Will
2002

This paper introduces an adaptive signal control system utilizing an on-line signal performance measure. Unlike conventional signal control systems, the proposed method employs real-time delay estimation and an on-line signal timing update algorithm. As a signal performance measure, intersection delay for each phase is measured in real-time via an advanced surveillance system that re-identifies individual vehicles both at upstream and downstream stations using vehicle waveforms obtained from advanced inductive loop detectors. In each cycle, the signal timing plan is optimized based on the...