Traffic Operations and Management

Experimental Verification of Discretely Variable Compression Braking Control for Heavy Duty Vehicles: Final Report

Vahidi, Ardalan
Stefanopoulou, Anna G.
Wang, Xiaoyong
Tsao, Tsu Chin
2004

In the first two chapters of this report, the development of discrete compression brake and transmission models is explained. In the vehicle model development, special efforts have been put in transmission shifting scheduling. Transmission up-shift and down-shift scheduling are separated in the modelling. Hysteresis during shifting is introduced to reduce chattering. A compression brake effect on transmission shifting is identified and considered in the modelling. The new transmission shifting model has been validated through experimental data. The transmission shifting model is combined...

Study of Integrated Corridor Management for San Francisco Bay Area I-880 Corridor

Zhang, Wei-Bin
Li, Irene
Shladover, Steven
Li, Meng
Alm, Erik
Ban, Jeff
Victor, Radiah
Yee, Albert
Stanislaus, Danielle
Chow, Alan
Nozzari, Sean
Minoofar, Cyrus
Yarjani, Bijan
Spencer, Tina
Broadbent, Patricia
Alexiadis, Vassili
Hatata, Tarek
Nejad, Anush
Shamskhou, Habib
2008

This document summarizes the efforts by the San Francisco Bay Area ICM team to develop the concept of operation, data needs and performance requirements for an Integrated Corridor management System for I-880 Corridor. Although the transportation management systems at the Bay Area are consistent with the regional ITS plans, these management systems are less integrated. It is believed that higher lebel of intergration among freeway and arterial systems, transit systems with consideration of all transportation needs demands in the region will greatly enhance and improve the efficiency and...

Spatial and Temporal Factors in Estimating the Potential of Ride-Sharing for Demand Reduction

Tsao, H.-S. Jacob
Lin, Da-Jie
1997

This study reports on a method to accomplish sensor validation and fusion in Intelligent Transportation Systems (ITS). The method is based on probabilistic and fuzzy techniques that express a confidence in the sensor data and take into account environmental factors and the state of the system. Sensor data fusion uses the confidence assigned to each sensor reading and integrates them into one reading. Noise and failure are filtered from the data and lead to a safety improvement in ITS.

Second Annual Symposium on Advanced Traffic Management Systems (ATMS) and Advanced Traveler Information Systems (ATIS), November 5, 1990

Haldors, Bruce
Bozzini, Anna
May, Adolf D.
1990

The purpose of the Symposium on Advanced Traffic Management Systems (ATMS) and Advanced Traveler Information Systems (ATIS) was to allow researchers involved in ATM/ATIS work to become familiar with other research in those areas in the state of California. This document provides a brief summary outlining the presentations made at the symposium.

Problem Sets: Fundamentals of Transportation and Traffic Operations

Daganzo, Carlos F.
1998

These problem sets comprise a supplement to Fundamentals of Transportation and Traffic Operations (C. Daganzo, Pergamon, 1997). Academicians can also obtain a companion set of solutions by writing to "Institute of Transportation Studies, Publications Office, 109 McLaughlin Hall, University of California, Berkeley, CA 94720" or by sending e-mail to its@its.berkeley.edu.

Presignal Used to Increase Bus- and Car-Carrying Capacity at Intersections: Theory and Experiment

2012

In theory midblock presignals can be used to increase the capacity of signalized intersections [The authors define “presignal” as “a set of signal heads that are installed in the middle of a block upstream of an intersection.”—Ed.]. The capacity is increased because presignals can reorganize how traffic is stored between a presignal and an intersection downstream. However, different vehicle classes have different acceleration characteristics, and the effectiveness of presignals hinges on the assumption of linear superposition; that is, the total time to discharge a mixture of distinct...

Potential Benefits of In-Vehicle Information Systems in a Real Life Freeway Corridor under Recurring and Incident-Induced Congestion

Al-deek, Haitham
1988

Optimal use of existing transportation facilities has become a major priority in congested urban areas. Providing real-time in-vehicle traffic information to drivers is one possibility of achieving this goal. This report documents an initial attempt to ascertain the potential benefits of a real-time in-vehicle traffic information system under recurring and non-recurring congestion conditions.

Optimizing Mixed Autonomy Traffic Flow with Decentralized Autonomous Vehicles and Multi-Agent RL

Vinitsky, Eugene
Lichtle, Nathan
Parvate, Kanaad
Bayen, Alexandre
2020

We study the ability of autonomous vehicles to improve the throughput of a bottleneck using a fully decentralized control scheme in a mixed autonomy setting. We consider the problem of improving the throughput of a scaled model of the San Francisco-Oakland Bay Bridge: a two-stage bottleneck where four lanes reduce to two and then reduce to one. Although there is extensive work examining variants of bottleneck control in a centralized setting, there is less study of the challenging multi-agent setting where the large number of interacting AVs leads to significant optimization difficulties...

Observations on European Advanced Traveler Information and Traffic Management Systems

Yim, Youngbin
Ygnace, Jean-luc
1993

This report documents the current state of Intelligent Vehicle Highway Systems (IVHS) technologies in Europe with special attention to advanced traveler information systems (ATIS) and advanced traffic management systems (ATMS). The views presented in the report are largely derived from information gathered at two conferences and from personal interviews with researchers and government authorities engaged in the European IVHS research effort. The report is organized into three sections: a brief description of the DRIVE I program, the current state of the DRIVE II program, and the status of...

Neural Network Models for Automated Detection of Non-recurring Congestion

Ritchie, Stephen G.
Cheu, Ruey L.
1993

This research addressed the first year of a proposed multi-year research effort that would investigate, assess, and develop neural network models from the field of artificial intelligence for automated detection of non- recurring congestion in integrated freeway and signalized surface street networks. In this research, spatial and temporal traffic patterns are recognized and classified by an artificial neural network.