Download or read book Simulation based Optimization of Actuated Traffic Signal Plans written by Tamir Balasha and published by . This book was released on 2015 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of the Stochastic Optimization Method in Optimizing Traffic Signal Control Settings written by Byungkyu Park and published by . This book was released on 2008 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traffic congestion has greatly affected not only the nation's economy and environment but also every citizen's quality of life. A recent study shows that every American traveler spent an extra 38 hours and 26 gallons of fuel per year due to traffic congestion during the peak period. Of this congestion, 10% is attributable to improper operations of traffic signals. Surprisingly, more than a half of all signalized intersections in the United States needs to be re-optimized immediately to maintain peak efficiency. Even though many traffic signal control systems have been upgraded from pre-timed controllers to actuated and adaptive controllers, the traffic signal optimization software has not been kept current. For example, existing commercial traffic signal timing optimization programs including SYNCHRO and TRANSYT-7F do not optimize advanced controller settings available in the modern traffic controllers including minimum green time, extension time, and detector settings. This is in part because existing programs are based on macroscopic simulation tools that do not explicitly consider individual vehicular movements. To overcome such a shortcoming, a stochastic optimization method (SOM) was proposed and successfully applied to a signalized corridor in Northern Virginia. This study presents enhancements made in the SOM and case study results from an arterial network consisting of 16 signalized intersections. The proposed method employs a distributed computing environment (DCE) for faster computation time and uses a shuffled frog-leaping algorithm (SFLA) for better optimization. The case study results showed that the proposed enhanced SOM method, called SFLASOM, improved the total network travel times over field settings by 3.5% for Mid-Day and 2.1% for PM-Peak. In addition, corridor travel times were improved by 2.3% to 17.9% over field settings. However, when the new SOM timing plan was compared to the new field timing plan implemented in July 2008, the improvements were marginal, showing slightly over 2% reductions in individual vehicular delay.
Download or read book Multi model Simulation based Optimization Applied to Urban Transportation written by Krishna Kumar Selvam and published by . This book was released on 2014 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation agencies often resort to the use of traffic simulation models to evaluate the impacts of changes in network design or network operations. They often have multiple traffic simulation tools that cover the network area where changes are to be made. Nonetheless, these multiple simulators may differ in their modeling assumptions (e.g., macroscopic versus microscopic), in their reliability (e.g., quality of their calibration) as well as in their modeling scale (e.g., city-scale model versus regional-scale model). The choice of which simulation model to rely on, let alone of how to combine their use, is intricate. A larger-scale model may, for instance, capture more accurately the local-global interactions; yet may do so at a greater computational cost. This thesis proposes a methodology that enables the simultaneous use of multiple traffic simulation models. We propose a simulation-based optimization algorithm that embeds information from simulation models with different levels of accuracy and with different levels of computational efficiency. The algorithm combines the use of high-accuracy low-efficiency models with low-accuracy high-efficiency models. This combination leads to an algorithm that can identify points (e.g., network designs, traffic management strategies) with good performance at a reduced computational cost. We evaluate the performance of the algorithm with a traffic signal control problem on a small network, as well a large-scale city network. We show that the proposed algorithm identifies signal plans with excellent performance, i.e., with reduced average trip travel times, while doing so with a reduction in the computational cost.
Download or read book Improving Performance of Coordinated Signal Control Systems Using Signal and Loop Data written by Meng Li (Writer on traffic signs and signals) and published by . This book was released on 2010 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance Evaluation of Dynamic Gap out Feature Using Stochastic Optimization Method and Software in the Loop Simulation written by Seli James Agbolosu-Amison and published by . This book was released on 2008 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organic Traffic Control written by Holger Prothmann and published by KIT Scientific Publishing. This book was released on 2014-08-25 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern cities cannot be imagined without traffic lights controlling the road network. To handle the network's changing demands efficiently, the signal plan specification needs to be shifted from the design time to the run-time of a signal system. The generic observer/controller architecture proposed for Organic Computing facilitates this shift. A two-levelled learning mechanism optimises signal plans on-line while a distributed coordination mechanism establishes green waves in the road network.
Download or read book Evaluation of Traffic Signal Timing Optimization Methods Using a Stochastic and Microscopic Simulation Program written by Byungkyu Park and published by . This book was released on 2003 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study evaluated existing traffic signal optimization programs including Synchro, TRANSYT-7F, and genetic algorithm optimization using real-world data collected in Virginia. As a first step, a microscopic simulation model, VISSIM, was extensively calibrated and validated using field data. Multiple simulation runs were then made for signal timing plans such that drivers' behavior, day-to-day traffic variation, etc. were considered in the evaluation. Finally, long-term demand growth or changes were statistically modeled and evaluated, again using multiple simulation runs. Five timing plans were evaluated using the simulation test bed. The timing plans under evaluation included (1) the former timing plan of the Virginia Department of Transportation(VDOT), (2) VDOT's current timing plan, (3) the genetic algorithm optimized timing plan, (4)the Synchro optimized timing plan, and (5) the TRANSYT-7F optimized timing plan. The simulation study results indicated that the current practice of VDOT's current signal optimization procedure significantly improved upon its former one by reducing travel times by 17% and total system delay by 36%. The three "optimized" timing plans did not provide significant improvements. Evaluation of the Lee-Jackson Memorial Highway network showed that the current VDOT signal optimization procedure significantly improved the performance of network operations. Thus, the study recommended that VDOT continue using its procedure for developing new timing plans but that it evaluate its signal timing plan regularly so that it does not become outdated
Download or read book Optimisation of Vehicle actuated Traffic Signal Controllers by Simulation Experiment written by and published by . This book was released on 1988 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book National Signal Timing Optimization Project written by and published by . This book was released on 1982 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the results of the National Signal Timing Organization Project initiated by the Federal Highway Administration as a fuel conservation effort. The objectives of this project are: 1) to establish credible data on the effectiveness of signal timing optimization; 2) to make signal timing optimization projects easier to do; and 3) to define the resources (cost, level of staff, computer, etc.) required to undertake a signal timing optimization project, so that traffic engineers and administrators can more effectively budget for this activity. The project consisted of the development of the TRANSYT-7F signal timing optimization program User's Manual, and training course, and application of the program in 11 cities nationwide to evaluate the effectiveness of the poptimized signal timing plans and to collect data on the needed resources.
Download or read book Development and Testing of a Constrained Optimization Model for Traffic Signal Plan Transition written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In advanced traffic signal control systems, traffic signal plan transition is the process of switching from one timing plan to another to accommodate changes in traffic demand. In traditional coordinated system operation, whether plans are set by time of day or by traffic responsive plan selection, traffic flow can be severely disrupted by the sudden changes in traffic signal timing plans. Even in case of advanced traffic control systems such as Sydney Coordinated Adaptive Traffic System (SCATS), the flow disruption during the transition period can cause a temporary, but sharp decline in system performance. Therefore, the quest for a signal plan transition method that minimizes flow disruption during the transition period is well motivated. Although various transition methods have been developed and refined, existing transition methods are not based on optimizing operational measures of effectiveness during plan transition periods. As the first step in remedying this situation, this research developed a non-linear mathematical model that provides constrained delay minimization through incremental and simultaneous adjustments in offset, cycle length, and phase splits during plan transitions. A simulation study was performed to comparatively evaluate the delay performance of the proposed versus existing transition methods. Also, statistical analyses using ANOVA and multi-comparison tests were conducted to validate the simulation results. According to the analysis results, currently used transition methods tend to assign an excessive amount of green time to the main street, resulting in additional side street delay without performance improvement for the total transportation network. By contrast, the proposed transition method showed measurable improvement in delay performance under a broad range of traffic and geometric conditions.
Download or read book Quantifying the Benefits of Coordinated Actuated Traffic Signal Systems written by Byungkyu Park and published by . This book was released on 2010 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coordinated actuated traffic signal systems have been widely implemented for the past few decades because they provide better progression along the major corridors through proper coordination. However, little has been done to quantify the benefits that can be obtained from coordinated traffic signal systems. Most efforts reported in the literature focused on system performance estimated from simulation software as opposed to field studies. The purpose of this study was to quantify the benefits of coordinated actuated traffic signal systems by conducting an analysis of before-and-after data. The travel time on the coordinated arterials and the stopped delay on a few key approaches were selected as measures of effectiveness. Synchro, a macroscopic traffic signal timing evaluation and optimization software, was used to generate the coordinated actuated traffic signal timing plans for comparison purposes. In addition, the performance of an adaptive split feature, implemented within the coordinated actuated traffic signal system, was evaluated through a before-and-after study. The data showed an improvement in performance of the coordinated actuated system over the actuated isolated system (the before condition), including a 30 percent reduction in travel times on the coordinated corridor. There was a corresponding increase in stopped delay on non-coordinated approaches, but the addition of the adaptive split feature was able to reduce this delay by 40 percent at one site without impacting progression on the coordinated approaches. The study recommends that the Virginia Department of Transportation regional traffic engineers implement the coordinated actuated traffic signal system over the non-coordinated system and the adaptive split feature with the coordination to reduce delays on side street approaches. Further, a cost/benefit analysis indicated that the coordinated actuated traffic signal system has a benefit/cost ratio of 461.3 when compared to the non-coordinated actuated traffic signal system.
Download or read book Optimisation of Vehicle actuated Traffic Signal Controllers by Simulation Experiment written by Martin John Rowe and published by . This book was released on 1988 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Improved Traffic Signal Coordination Strategies for Actuated Control written by Carroll J. Messer and published by . This book was released on 1996 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents research conducted to develop better strategies to use with traffic actuated control in coordinated signal systems. Recommendations are presented on more efficient strategies for coordination using actuated control. Representative arterial traffic control problems were modeled into a statistical testbed using TRAF-NETSIM. A set of scenarios covering a range of arterial geometry, traffic volumes and traffic actuated control settings were tested and evaluated. PASSER II-90 was used to develop base signal timing plans. Chapter One describes the various objectives that were intended to be achieved by this research. It also discusses signal coordination strategies for actuated control. Chapter Two presents the background information and various traffic engineering simulation models available for use in this study. Chapters Three and Four explain the study methodology adopted for this research and the results obtained for the various study scenarios, respectively. Chapter Five presents the conclusions and recommendations of the research.
Download or read book Development of Traffic Signal Training Materials Integrating Hardware in the loop Simulation written by Michael Dixon and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Traffic Signal Timing Manual written by U.s. Department of Transportation and published by CreateSpace. This book was released on 2015-02-20 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report serves as a comprehensive guide to traffic signal timing and documents the tasks completed in association with its development. The focus of this document is on traffic signal control principles, practices, and procedures. It describes the relationship between traffic signal timing and transportation policy and addresses maintenance and operations of traffic signals. It represents a synthesis of traffic signal timing concepts and their application and focuses on the use of detection, related timing parameters, and resulting effects to users at the intersection. It discusses advanced topics briefly to raise awareness related to their use and application. The purpose of the Signal Timing Manual is to provide direction and guidance to managers, supervisors, and practitioners based on sound practice to proactively and comprehensively improve signal timing. The outcome of properly training staff and proactively operating and maintaining traffic signals is signal timing that reduces congestion and fuel consumption ultimately improving our quality of life and the air we breathe. This manual provides an easy-to-use concise, practical and modular guide on signal timing. The elements of signal timing from policy and funding considerations to timing plan development, assessment, and maintenance are covered in the manual. The manual is the culmination of research into practices across North America and serves as a reference for a range of practitioners, from those involved in the day to day management, operation and maintenance of traffic signals to those that plan, design, operate and maintain these systems.
Download or read book Improving Traffic Signal Operations written by and published by . This book was released on 1995 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wilhelm B Deckert Family Reunion Records written by and published by . This book was released on 1954 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
