Traffic Operations and Management

Regulation Layer Software Integration

Deshpande, Akash R.
1999

The project reuses the sensor and actuator interface software developed by California PATH for the DEN1097 automated highway system demonstration on Highway I17 in San Diego during August 1997. This software is provided on the QNX operating system. It interfaces with the magnetometers, radars, and the various intenal sensors such as wheel speed, engine speed, steering angle, etc, as well as with the actuators such as throttle, brake, and steering. In this project, we wrote an interface process that communicates between the driver process described above and the controller process described...

San Francisco Bay Area US-101 Existing Conditions, ITS Assets, and Active Transportation and Demand Management Assessment

McKeever, Benjamin
Skabardonis, Alexander
Mauch, Michael
Campbell, Robert
Alexiadis, Vassili
Wornum, Christopher
2018

The 58.5-mile long Highway 101 corridor from the Bay Bridge to the SR 85/US-101 interchange in South San Jose accommodates just over 2.6 million trips on an average weekday. Travel delays on the US-101 corridor over the 2012-2016 five-year period increased by more than 91% (an average delay increase of over 18% per year). Given that California’s economy recently grew to become the sixth largest in the world, this waste of time stuck in traffic ranks among the most consequential economic inefficiencies in the world; workers in this region produce about 15 percent of California’s annual...

Collision Avoidance Analysis for Lane Changing and Merging

Jula, Hossein
Kosmatopoulos, Elias B.
Ioannou, Petros A.
1999

One of the riskiest maneuvers that a driver has to perform in a conventional highway system is tomerge into the traffic and/or to perform a lane changing maneuver. Lane changing/mergingcollisions are responsible for one-tenth of all crash-caused traffic delays often resulting incongestion. Traffic delays and congestion, in general, increases travel time and has a negativeeconomic impact.In this paper, we analyze the kinematics of the vehicles involved in a lane changing/mergingmaneuver, and study the conditions under which lane changing/merging crashes can be avoided.That is, given a...

A Review of the Optimized Policies for Adaptive Control Strategy (OPAC)

Liao, Lawrence C.
1998

Optimized Policies for Adaptive Control (OPAC) is a real-time demand-responsive traffic signal timing optimization algorithm for individual intersections. It was developed at University of Lowell under the sponsorship of U.S. Department of Transportation in the early 80s. OPAC distinguishes itself from traditional cycle-split signal control strategies by dropping the concept of cycle. In OPAC, the signal control problem consists of a sequence of switching decisions made at fixed time intervals. At each decision point the question is whether to extend or terminate current phase. Dynamic...

Using Cooperative Adaptive Cruise Control (CACC)to Form High-Performance Vehicle Streams. Definitions, Literature Review and Operational Concept Alternatives

Shladover, Steven E.
Nowakowski, Christopher
Lu, Xiao-Yun
2018

Cooperative Adaptive Cruise Control (CACC) is a term that has been used rather loosely in recent years, such that different people visualize different functions and capabilities when discussing CACC systems. Thus, there are now multiple system concepts that have been described under the CACC label, and the functionalities included in these varied concepts can be quite different from each other. At the heart of each CACC concept is the merging of Adaptive Cruise Control (ACC), a subset of the broader class of automated speed control systems, with acooperative element, such a Vehicle-to-...

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...

Development of an Adaptive Corridor Traffic Control Model

Recker, Will
2008

This report documents work performed on PATH TO 5323. Due to an administrative mandate, the work performed and reported herein constitutes only the early stages of the multi-year project that was approved under PATH TO 5323, and subsequently divided into two distinct awards—TO 5323 and TO 6323. Moreover, a series of events during the early stages of the project substantially redirected the original effort. These factors led to a major redirection from the original project. The majority of the work performed under the revised TO 5323 was then to develop a methodology consistent with the new...

Turning Movement Estimation In Real Time (TMERT)

Martin, Peter T.
1995

This report describes the development of a new model that can monitor system performance and derive management and control strategies in real time. It presents the TMERT (Turning Movement Estimation in Real Time) model, a method of estimating turning movement flows from link detected flows at small recurrent intervals, in real time.

Development of an Integrated Microscopic Traffic Simulation and Signal Timing Optimization Tool

Yin, Yafeng
Liu, Henry X.
Laval, Jorge A.
Lu, Xiao-Yun
Li, Meng
Pilachowski, Joshua
Zhang, Wei-Bin
2007

A big segment of the traffic signal control systems in California and United States are closed-loop systems. Because wide-scale deployment of advanced adaptive control systems may be many years away due to the associated high costs, there is a significant need to improve the effectiveness of the state-of-the-practice closed-loop systems. To address the need, this project focuses on: 1) developing an integrated micro-simulation/signal optimization tool to enhance the capability of generating efficient signal timing plans, and 2) developing a systematic approach to make closed-loop systems...

Implementation of Advanced Techniques for Automated Freeway Incident Detection

Abdulhai, Baher
Ritchie, Stephen G.
Iyer, Mahadevan
1999

A significant body of research on advanced techniques for automated freeway incident detection has been conducted at the University of California, Irvine (UCI). Such advanced pattern recognition techniques as artificial neural networks (ANNs) have been thoroughly investigated and their potential superiority to other techniques has been demonstrated. Of the investigated ANN architectures, two have shown the best potential for real-time implementation: namely, the Probabilistic Neural Network (PNN), (Abdulhai and Ritchie 1997), and the Multi-Layer-Feed-Forward Neural Network (MLF), (Cheu and...