Traffic Operations and Management

Developing Calibration Tools for Microscopic Traffic Simulation Final Report Part III: Global Calibration - O-D Estimation, Traffic Signal Enhancements and a Case Study

Zhang, Michael
Ma, Jingtao
Singh, Shailendra P.
Chu, Lianyu
2008

The central goal of this research is to develop a systematic framework and the support tools to ease, streamline and speed up the calibration of micro simulation projects. Part III of the final report documents the accomplishments achieved in the second phase of the research project. They include the following.First, to overcome the lengthy time it takes for GA to obtain local and global driving behavior modeling parameters, we implemented a faster heuristic optimization technique, the simultaneous perturbation stochastic approximation (SPSA) and compared its performance with other...

New Approach to Bottleneck Capacity Analysis: Second Interim Report, Work Accomplished During Fiscal Year 2004-2005

Banks, James
2006

This report documents work accomplished during Fiscal Year 2005-2005 as a part of a research project entitled “New Approach to Bottleneck Capacity.” This project is developing an alternative to the traditional Highway Capacity Manual approach to capacity analysis in which capacity flow [either pre-queue flow (PQF) or queue discharge flow (QDF)] is related to a set of intervening variables, including the average time gaps in the critical lane (i. e., that with the highest flow rate) and the distribution of flow across the lanes, represented by the critical lane flow ratio (i. e., the flow...

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.