Traffic Operations and Management

Fuel-Efficient Traffic Signal Management. Three Years of Experience 1983-85

Deakin, E A
Skabardonis, A
University of California, Berkeley
California Energy Commission
California Department of Transportation
1985

Nearly one-fifth of California's annual petroleum consumption occurs on streets controlled by traffic signals. This report presents results from three years of a statewide initiative to retime those signals to produce more energy-efficient traffic flow: the Fuel-Efficient Traffic Signal Management (FETSIM) Program. To date, sixty-one cities and one county have retimed a total of 3,172 signals under grants from the FETSIM Program. Improved timings have reduced vehicular delays by over 15 percent in project areas, and stops have been decreased by 16 percent, resulting in smoother traffic...

Freeway Traffic Shockwave Analysis: Exploring NGSIM Trajectory Data

Lu, Xiao-Yun
Skabardonis, Alexander
Transportation Research Board
2007

The paper presents the development and application of a numerical algorithm to estimate the propagation speed of shockwaves on freeways based on vehicle trajectory data. The essence of the algorithm is that the shockwave propagation speed is the traveling speed of local minima of consecutive vehicle speed trajectories. The application of the algorithm on the NGSIM datasets from the I-80 and US101 freeways under congested conditions shows that all the shockwaves have similar propagation speed of about 11.4 mph (18.34 kph), which is independent of the traffic flow speed prior to congestion....

Freeway Service Patrol Evaluation

Skabardonis, Alexander
University of California, Berkeley
California Department of Transportation
1995

This report presents the findings of a comprehensive evaluation of the freeway service patrol (FSP) program on specific freeway section in the San Francisco Bay Area. The study methodology consisted of determining the savings in incident delay and other performance measures "before" and " after" the implementation of FSP based on field data and improved analysis procedures. Data were collected during the peak periods on a mile section of the I-880 freeway in the City of Hayward, Alameda County. Software was developed to process the field data and create a computerized database. Benefits of...

Freeway Performance Measurement System: Operational Analysis Tool

Choe, T
Skabardonis, A
Varaiya, P
Transportation Research Board
2002

The freeway performance measurement system (PeMS) is a system for all of California. It processes 2 gigabytes/day of 30-s loop detector data in real time to produce useful information. Managers at any time can have a uniform and comprehensive assessment of freeway performance. Traffic engineers can base their operational decisions on knowledge of the current state of the freeway network. Planners can determine whether congestion bottlenecks can be alleviated by improving operations or by minor capital improvements. Travelers can obtain the current shortest route and travel time estimates....

Freeway Performance Measurement System: Mining Loop Detector Data

Chen, Cong
Petty, K
Skabardonis, A
Varaiya, P
Jia, Z
Transportation Research Board
2001

Performance Measurement System (PeMS) is a freeway performance measurement system for all of California. It processes 2GB/day of 30-s loop detector data in real time to produce useful information. At any time managers can have a uniform, comprehensive assessment of freeway performance. Traffic engineers can base their operational decisions on knowledge of the current status of the freeway network. Planners can determine whether congestion bottlenecks can be alleviated by improving operations or by minor capital improvements. Travelers can obtain the current shortest route and travel time...

Transportation Research Record: Journal of the Transportation Research Board

Halkias, Bill M
Kopelias, Pantelis
Papandreou, Konstantinos
Politou, Anna
Prevedouros, Panos D
Skabardonis, Alexander
2012

A fully documented case of problem identification, simulation, implementation, and evaluation has been developed for freeway bottleneck congestion mitigation. The benefits of using simulation for assessing improvement scenarios of a congestion-generating merge between two freeways and an on-ramp in the central part of Attica Tollway in Athens, Greece, are presented. The best feasible alternative identified by two simulation programs, Integration and VisSim, was constructed, and before and after field and simulation results are available. Only 16 months passed between the initial data...

Framework for Analysis of Recurring Freeway Bottlenecks

Skabardonis, Alexander
Rouphail, Nagui M
Petty, Karl
Dowling, Richard G
Transportation Research Board
2008

Recent statistics indicate a dramatic increase in congestion delay due to recurrent freeway bottlenecks. Proper identification of freeway bottlenecks and their causes is the key to formulating plans for reducing congestion. Relatively low-cost geometric and operational improvements can often mitigate the effects of a bottleneck. The paper presents the findings to-date on an ongoing NCHRP project on low cost improvements for recurring freeway bottlenecks. The research surveyed the state of the art and practice both in the US and overseas, proposed a definition of bottlenecks, bottleneck...

Flow-aware platoon formation of Connected Automated Vehicles in a mixed traffic with human-driven vehicles

Woo, Soomin
Skabardonis, Alexander
2021

Connected Automated Vehicles (CAVs) bring promise of increasing traffic capacity and energy efficiency by forming platoons with short headways on the road. However at low CAV penetration, the capacity gain will be small because the CAVs that randomly enter the road will be sparsely distributed, diminishing the probability of forming long platoons. Many researchers propose to solve this issue by platoon organization strategies, where the CAVs search for other CAVs on the road and change lanes if necessary to form longer platoons. However, the current literature does not analyze a potential...

Field Testing the Effectiveness of Adaptive Traffic Control for Arterial Signal Management

Campbell, Robert
Skabardonis, Alexander
University of California, Berkeley
2014

The report describes the methodology and findings of the evaluation of adaptive signal control in a real-life corridor. The study section was a five mile section of the Pacific Coast Highway in Los Angeles with nine signalized intersections operating under adaptive control using the Los Angeles DOT ATCS (adaptive traffic control system). Optimal fixed time time-of-day plans were developed and implemented at the test site. The performance of the ATCS system and the fixed-time plans was evaluated using extensive field data on travel times and queue lengths collected through probe vehicles,...

Feasibility and demonstration of network simulation techniques for estimation of emissions in a large urban area

Skabardonis, A
Deakin, Harvey, Skabardonis, Incorporated
1994

The objective of this study was to investigate the possibility of using microscale network simulation computer models to estimate motor vehicle activity for a large urban area. Existing network simulation models are capable of resolving vehicle activity down to the individual vehicle level, and are used to study traffic movements for small areas such as intersections or short sections of highway. Regional travel demand models have historically not been used for the purpose of emissions estimation, and thus poorly define elements of vehicle operation such as accelerations and decelerations...