Traffic Operations and Management

Traffic Management Systems Performance Measurement: Working Paper #2

Banks, James H.
Kelly, Gregory
1997

Traffic Data System Improvement Plans were prepared for Caltrans Districts 1 1 (San Diego) and 12 (Orange County) as part of a research project on performance measurement for traffic management systems. The plans document data system objectives, data requirements, and existing data collection and management systems; evaluate the adequacy of existing systems; identify improvements and resource requirements; and document the districts’ priorities for action. Both districts have similar data systems, although Orange County’s is better developed. Both systems rely heavily on single-loop...

TravInfo Evaluation (Technology Element) Traveler Information Center (TIC) Study: Operator Response Time Analysis

Miller, Mark A.
Loukakos, Dimitri
2000

TravInfo (TM) is an advanced traveler information system for the San Francisco Bay Area that began operation in September 1996 under a public/private partnership. The public sector component centers on the Traveler Information Center (TIC), TravInfo (TM)'s information gathering, processing, and dissemination hub. For two years, until September 1998, TravInfo (TM) was a Field Operational Test (FOT) sponsored by the Federal Highway Administration. During the FOT, the TIC was evaluated. This report documents the analysis of operator response time. Response times remained stable throughout the...

Dynamic Traffic Assignment For Automated Highway Systems: A Two-lane Highway With Speed Constancy

Tsao, H. S. Jacob
1996

Dynamic traffic assignment through analytical modeling and optimization has been widely accepted by the IVHS R&D community as a promising traffic control tool for understanding and relieving traffic congestion on conventional highways and city streets. Due to the completely controlled nature of AHS traffic, dynamic assignment of AHS traffic is even more promising. One added dimension of complexity associated with AHS dynamic traffic assignment is lane assignment. Lane changes, for fully utilizing AHS capacity or for exiting, incur disturbances to and hence reduction of longitudinal...

Highway Electrification: An Exploration of Energy Supply Implications

Wang, Quanlu
Sperling, Daniel
1987

The objective of this preliminary report is to explore the energy supply opportunities and implications of electrifying highways. An important assumption in this report is that the technology and general cost structure for generating and storing electricity does not change significantly in the future. In other words, we ignore the possible use of super conductive materials to store electricity during off-peak times, which, if feasible, would greatly reduce average electricity costs. A future report will examine the opportunities and implications of breakthroughs in superconductivity.The...

Experimental Characterization of Multi-Lane Freeway Traffic Upstream of an Off-Ramp Bottleneck

Munoz, Juan Carlos
Daganzo, Carlos
2000

This report describes field observations of multi-lane freeway traffic upstream of an oversaturated off-ramp. It is based on empirical evidence from freeway I-880 (northbound) near Oakland, California. The report presents two diagnostic tools that reveal hidden features of the traffic stream and, based on these findings, proposes congestion mitigation strategies that could work for similar locations with little or no construction.

Major Failure Events of Automated Highway Systems: Three Scenarios from the Driver’s Perspective

Tsao, H.-S. Jacob
Plocher, Thomas A.
Zhang, Wei-Bin
Shladover, Steven E.
1997

Automated Highway Systems (AHS) have the potential for offering large capacity and safety gains without requiring significant amounts of additional right-of-way. Since the general public will be the users of the AHS, human factors must play a pivotal role in the research and development of AVCS technologies and AHS operation. In two companion reports, three attributes critical to AHS human factors were identified and seven scenarios featuring variations in these attributes proposed. To ensure the identification of all major compounding attribute combinations, detailed operational events,...

Time Space Diagrams For Thirteen Shock Waves

Coifman, Benjamin
1997

This paper presents microscopic time-space diagrams for several shock waves over 100-200m distances. The primary focus of the paper is on presenting the data rather than analysis. The diagrams should be of general interest to researchers studying traffic congestion.

A Link-Based Variational Inequality Model for Dynamic Departure Time/Route Choice

Ran, Bin
Hall, Randolph
Boyce, David E.
1995

The dynamic user-optimal (DUO) departure time and route choice problem is to determine travelers’ best departure times and route choices at each instant of time. In a previous paper, we presented a route-based two-level optimal control model for the DUO departure time/route choice problem. However, this model is not appropriate for large scale transportation networks because some degree of route enumeration is necessary to solve the model. In this paper, we present a link-based variational inequality (VI) formulation for the DUO departure time/route choice problem so that route enumeration...

Robust Computation of Optical Flow in a Multi-Scale Differential Framework

Weber, Joseph
Malik, Jitendra
1993

We have developed a new algorithm for computing optical flow in a differential framework. The image sequence is first convolved with a set of linear, separable spatiotemporal filters similar to those that have been used in other early vision problems such as texture and stereopsis. Our analysis of the measurement errors leads us to develop an algorithm based on a robust version of total least squares. Each optical flow vector computed has an associated reliability measure which can be used in subsequent processing. The performance of the algorithm on the data set used by Barron et al. (...

Los Angeles Fot Spread Spectrum Radio Traffic Signal Interconnect Evaluation Task: Final Report On Full Deployment

Li, Victor O. K.
Sengodan, Senthil
Chan, Tat-keung Ken
Zhuge, Lei
1998

This report presents the results of an evaluation of project in which spread spectrum radio networks (SSRN) were used for traffic monitoring and control in the City of Los Angeles. The focus of SSRN is to reduce construction costs, construction time and future plant maintenance costs. A field operational test was conducted to test and evaluate the applicability of SSRN communications in traffic control.