scholarly journals An Integrated Variable Speed Limit and ALINEA Ramp Metering Model in the Presence of High Bus Volume

2019 ◽  
Vol 11 (22) ◽  
pp. 6326 ◽  
Author(s):  
Dadashzadeh ◽  
Ergun
Keyword(s):  
Management Strategies ◽  
Congestion Management ◽  
Simulation Software ◽  
Urban Transport ◽  
Ramp Metering ◽  
Mixed Traffic ◽  
Variable Speed ◽  
Microscopic Simulation ◽  
Proposed Model ◽  
Total Travel Time

Under many circumstances, when providing full bus priority methods, urban transport officials have to operate buses in mixed traffic based on their road network limitations. In the case of Istanbul's Metrobus lane, for instance, when the route comes to the pre-designed Bosphorus Bridge, it has no choice but to merge with highway mixed traffic until it gets to the other side. Much has been written on the relative success of implementing Ramp Metering (RM), for example ALINEA (‘Asservissement line´ aire d’entre´ e autoroutie’) and Variable Speed Limits (VSL), two of the most widely-used “merging congestion” management strategies, in both a separate and combined manner. However, there has been no detailed study regarding the combination of these systems in the face of high bus volume. This being the case, the ultimate goal of this study is to bridge this gap by developing and proposing a combination of VSL and RM strategies in the presence of high bus volume (VSL+ALINEA/B). The proposed model has been coded using microscopic simulation software—VISSIM—and its vehicle actuated programming (VAP) feature; referred to as VisVAP. For current traffic conditions, the proposed model is able to improve total travel time by 9.0%, lower the number of average delays of mixed traffic and buses by 29.1% and 81.5% respectively, increase average speed by 12.7%, boost bottleneck throughout by 2.8%, and lower fuel consumption, Carbon Monoxide (CO), Nitrogen Oxides (NOx), and Volatile Organic Compounds (VOC) emissions by 17.3% compared to the existing “VSL+ALINEA” model. The results of the scenario analysis confirmed that the proposed model is not only able to decrease delay times on the Metrobus system but is also able to improve the adverse effects of high bus volume when subject to adjacent mixed traffic flow along highway sections.

scholarly journals Variable Speed Limit and Ramp Metering for Mixed Traffic Flows: A Review and Open Questions

2021 ◽  
Vol 11 (6) ◽  
pp. 2574
Author(s):  
Filip Vrbanić ◽  
Edouard Ivanjko ◽  
Krešimir Kušić ◽  
Dino Čakija
Keyword(s):  
Traffic Control ◽  
Ramp Metering ◽  
Transport Infrastructure ◽  
Control Algorithms ◽  
Speed Limit ◽  
Mixed Traffic ◽  
Traffic Flows ◽  
Variable Speed ◽  
Variable Speed Limit ◽  
Traffic Demand

The trend of increasing traffic demand is causing congestion on existing urban roads, including urban motorways, resulting in a decrease in Level of Service (LoS) and safety, and an increase in fuel consumption. Lack of space and non-compliance with cities’ sustainable urban plans prevent the expansion of new transport infrastructure in some urban areas. To alleviate the aforementioned problems, appropriate solutions come from the domain of Intelligent Transportation Systems by implementing traffic control services. Those services include Variable Speed Limit (VSL) and Ramp Metering (RM) for urban motorways. VSL reduces the speed of incoming vehicles to a bottleneck area, and RM limits the inflow through on-ramps. In addition, with the increasing development of Autonomous Vehicles (AVs) and Connected AVs (CAVs), new opportunities for traffic control are emerging. VSL and RM can reduce traffic congestion on urban motorways, especially so in the case of mixed traffic flows where AVs and CAVs can fully comply with the control system output. Currently, there is no existing overview of control algorithms and applications for VSL and RM in mixed traffic flows. Therefore, we present a comprehensive survey of VSL and RM control algorithms including the most recent reinforcement learning-based approaches. Best practices for mixed traffic flow control are summarized and new viewpoints and future research directions are presented, including an overview of the currently open research questions.

Microscopic Simulation on High-Class Roads: Enhancement of Environmental Analyses and Driving Dynamics: Practical Applications

2000 ◽  
Vol 1706 (1) ◽  
pp. 73-81 ◽  
Author(s):  
Ville Lehmuskoski ◽  
Jarkko Niittymäki ◽  
Björn Silfverberg
Keyword(s):  
Urban Areas ◽  
Management Strategies ◽  
Project Planning ◽  
Simulation Software ◽  
Urban Traffic ◽  
Detailed Calculation ◽  
Microscopic Simulation ◽  
Emission Analysis ◽  
Change Models ◽  
Practical Applications

Traffic is a very complex phenomenon. As the calculation power and capacity of computers have rapidly increased, the possibilities for modeling traffic corresponding better to reality have also increased. A noteworthy method for modeling is microscopic simulation of traffic, which can be used for a variety of needs. In general it can be stated that the interest in microsimulation lies in short-term functional studies rather than in the assessment of long-term needs. The design of concepts for traffic management strategies, especially for main transport corridors and urban traffic systems, constitutes a challenge for the user of microscopic simulation tools. In addition to practical project planning, microscopic traffic simulation can also provide a tool for research. Detailed calculation of emissions is of special interest in congested urban areas. Microscopic simulation of traffic provides comprehensive methods for detailed assessment of emissions as each individual vehicle is recorded with respect to its driving conditions and performance both in space and in time (speed, acceleration, deceleration). HUTSIM is a Finnish microscopic simulation software developed by the Helsinki University of Technology. Because it is rule based and object oriented, the operational comprehension of the software can be expanded quite easily. In many Finnish projects, HUTSIM has been expanded to better suit wide-scale applications. Development of emission analysis and lane-change models is described, as are future development outlines concerning modeling human behavior and analyzing the level of service using fuzzy methods.

Simulation and Analysis of the Variable Speed Limit Controls on Highway Maintenance

2011 ◽  
Vol 97-98 ◽  
pp. 435-439 ◽  
Author(s):  
Bai Ying Shi ◽  
Xue Yu Gao ◽  
Zhi Ge ◽  
Xue Ping Ma
Keyword(s):  
Traffic Safety ◽  
Traffic Control ◽  
Simulation Software ◽  
Speed Limit ◽  
Variable Speed ◽  
Work Zones ◽  
Microscopic Simulation ◽  
Variable Speed Limit ◽  
Control Zone ◽  
Organization And Management

Despite of the fact that the traffic control zone for maintenance work (work zone) has been recognized as one of major priorities to guarantee the traffic safety, only one conventional posted speed limit (PSL) strategy is applied into the organization and management. This article presents the strategy of the variable speed limit (VSL) on highway work zones that brings about gradual deceleration and low speed variance. To evaluate the safety of the proposed VSL strategy, this study uses the microscopic simulation software VISSM to estimate the traffic flow and adopt transversal and longitudinal coefficients of safety (MSDE and cv) to compare the different speed limit strategies. The results of simulation and analysis confirm that VSL yield a substantial decrease the traffic turbulence caused by speed limit and increase the traffic safety throughout work zones.

Fuzzy Ramp Metering: Design Overview and Simulation Results

1998 ◽  
Vol 1634 (1) ◽  
pp. 10-18 ◽  
Author(s):  
Cynthia Taylor ◽  
Deirdere Meldrum ◽  
Les Jacobson
Keyword(s):  
Fuzzy Logic ◽  
Travel Time ◽  
Fuzzy Controller ◽  
Simulation Software ◽  
Ramp Metering ◽  
Traffic Conditions ◽  
Total Distance ◽  
Total Travel Time ◽  
Vehicle Delay ◽  
Simulation Results

A fuzzy logic ramp-metering algorithm was designed to overcome the limitations of conventional ramp-metering strategies. The fuzzy controller demonstrated improved robustness, prevented heavy congestion, intelligently balanced conflicting needs, and tuned easily. The objective was to maximize total distance traveled and minimize total travel time and vehicle delay, while maintaining acceptable ramp queues. A multiple-ramp study site from the Seattle I-5 corridor was modeled and tested using the freeway simulation software, FRESIM. For five of the six testing sets, encompassing a variety of traffic conditions, the fuzzy controller outperformed the three other controllers tested.

scholarly journals A Study on the Merits for Coordinated Use of Ramp Metering and Variable Speed Limit Traffic Control Systems

2018 ◽  
Vol 12 (1) ◽  
pp. 230-245
Author(s):  
Mehdi Fallah Tafti
Keyword(s):  
Control Systems ◽  
Traffic Control ◽  
Network Performance ◽  
Synergistic Effects ◽  
Ramp Metering ◽  
Speed Limit ◽  
Variable Speed ◽  
Microscopic Simulation ◽  
Variable Speed Limit ◽  
Simulated Network

Aim:The aim of this research was to investigate the merits for further improvements of traffic operation on freeways and expressways through coordinated use of Ramp Metering and Variable Speed limit (VSL) control systems.Methods:In this research, the widely used ALINEA Ramp Metering strategy was coordinated with a rule-based VSL strategy so that the total flow entered from the upstream freeway and entry ramp is maintained below the merge downstream capacity. The developed algorithm was then examined on a freeway network comprising two merge and one diverge sections, using VISSIM microscopic simulation model. The performance of the simulated network was examined under three scenarios namely, No-control, Ramp Metering only and Ramp Metering plus VSL controls. The network performance under each scenario was then assessed and compared using three measures of performance namely, average travel time, overall delay and freeway throughput. The ANOVA test was used to analyze and compare the impacts of specified scenarios.Results:The results indicated that the best performance is achieved under coordinated Ramp Metering plus VSL scenario as it produced a significantly better performance in comparison with the other two scenarios.Conclusion:The results can be attributed to the synergistic effects of coordinated and integrated use of these control systems on the freeway network and therefore, coordination of such systems is recommended.

Development of a Microscopic Simulation Based Performance Evaluation Model to Compare Operational Improvements with Capacity Additions

2014 ◽  
Vol 668-669 ◽  
pp. 1476-1479
Author(s):  
Tang Tang ◽  
Da Zhi Sun ◽  
Vipinshankar Govindankutty
Keyword(s):  
Performance Evaluation ◽  
Evaluation Model ◽  
Capacity Expansion ◽  
Simulation Software ◽  
Ramp Metering ◽  
Microscopic Simulation ◽  
Performance Evaluation Model ◽  
Simulation Based ◽  
Operational Improvement ◽  
Expansion Strategies

The objective of this study is to develop a microscopic simulation model to objectively compare operational improvements with capacity expansions. Simulation software VISSIM was used to redesign the existing facilities for the performance evaluation of operational improvement and capacity expansion strategies from delay time, emission and fuel consumption perspective. Two case studies were performed with different test beds to evaluate the effectiveness of performance evaluation model, majorly involving dynamic speed, ramp metering and hard shoulder usage strategies which are discussed in detail to illustrate the changes due to operational improvement and capacity expansion strategies.

scholarly journals Modeling and Analysis of Mixed Traffic Networks with Human-driven and Autonomous Vehicles

2021 ◽  
Author(s):  
Qing Xu ◽  
Chaoyi Chen ◽  
Xueyang Chang ◽  
Dongpu Cao ◽  
Mengchi Cai ◽  
...  
Keyword(s):  
Autonomous Vehicles ◽  
Transportation Systems ◽  
Traffic Modeling ◽  
Traffic Networks ◽  
Mixed Traffic ◽  
Modeling And Analysis ◽  
Conservation Problem ◽  
Proposed Model ◽  
Total Travel Time ◽  
Research Gap

Abstract The emergence of connected and automated vehicles (CAV) indicates improved traffic mobility in future traffic transportation systems. This study addresses the research gap in macroscopic traffic modeling of mixed traffic networks where CAV and human-driven vehicles coexist. CAV behavior is explicitly included in the proposed traffic network model, and the vehicle number non-conservation problem is overcome by describing the approaching and departure vehicle number in discrete time. The proposed model is verified in typical CAV cooperation scenarios. The performance of CAV coordination is analyzed in road, intersection and network scenario. Total travel time of the vehicles in the network is proved to be reduced when coordination are applied. Simulation results validate the accuracy of the proposed model and the effectiveness of the proposed algorithm.

scholarly journals Using Microscopic Simulation-Based Analysis to Model Driving Behavior: A Case Study of Khobar-Dammam in Saudi Arabia

2019 ◽  
Vol 11 (11) ◽  
pp. 3018 ◽  
Author(s):  
Hassan M. Al-Ahmadi ◽  
Arshad Jamal ◽  
Imran Reza ◽  
Khaled J. Assi ◽  
Syed Anees Ahmed
Keyword(s):  
Saudi Arabia ◽  
Traffic Simulation ◽  
Management Strategies ◽  
Simulation Models ◽  
Driving Behavior ◽  
Transportation Systems ◽  
Simulation Software ◽  
Sustainable Transportation ◽  
Microscopic Simulation

Sustainable transportation systems play a key role in the socio-economic development of a country. Microscopic simulation models are becoming increasingly useful tools in designing, optimizing, and evaluating the sustainability of transportation systems and concerned management strategies. VISSIM, a microscopic traffic simulation software, has gained rapid recognition in the field of traffic simulation. However, default values for different input parameters used during simulation need to be tested to ensure a realistic replication for local traffic conditions. This paper attempts to model driving behavior parameters using the microscopic simulation software VISSIM through a case study in the Khobar-Dammam metropolitan areas in Saudi Arabia. VISSIM default values for different sensitive parameters such as lane change distances, additive and multiplicative parts of desired safety distances, the number of preceding vehicles spotted, amber signal decisions, and minimum headway were identified to be most sensitive and significant parameters to be calibrated to precisely replicate field conditions. The simulation results using default values produced higher link speed, larger queue length, and shorter travel times than those observed in the field. However, measures of effectiveness (MOEs) obtained from calibrated models over desired simulation runs were comparable to those obtained from field surveys. All compared MOEs used to validate the model matched within a range of 5–10% to the field-observed values.

Implementation of Active Traffic Management Strategies for Safety on Congested Expressway Weaving Segments

2017 ◽  
Vol 2635 (1) ◽  
pp. 28-35 ◽  
Author(s):  
Ling Wang ◽  
Mohamed Abdel-Aty ◽  
Jaeyoung Lee
Keyword(s):  
Traffic Safety ◽  
Traffic Management ◽  
Management Strategies ◽  
Ramp Metering ◽  
Assessment Model ◽  
Variable Speed ◽  
Analysis Model ◽  
Variable Speed Limit ◽  
Average Travel Time ◽  
The Impact

In weaving segments, traffic merges, diverges, and weaves in a limited space. These traffic maneuvers might result in high crash hazards. To improve the safety of a congested expressway weaving segment, this study tested various active traffic management (ATM) strategies in microsimulations. Crash odds and the Surrogate Safety Assessment Model were used to evaluate the impact of ATM strategies on traffic safety. The crash odds were calculated based on the real-time safety analysis model for weaving segments. The strategies included ramp metering (RM), variable speed limit (VSL), and integrated RM and VSL (RM-VSL). Overall, the results showed that the ATM strategies improved the safety of the studied weaving segment. The modified ALINEA RM algorithms, which took lane occupancy and safety into consideration, outperformed the traditional ALINEA algorithm from a safety perspective. The 45 mph VSLs, which were located at the upstream of the studied weaving segment, significantly enhanced safety without notably increasing average travel time. A consolidated RM-VSL strategy was also proposed with the aim of improving traffic safety by implementing RM and VSL. In the consolidated RM-VSL strategy, the modified ALINEA RM was adjusted according to the queue length to prevent long queues on ramps. The results proved that the consolidated RM-VSL strategy reduced the number of conflicts by 16.8% and decreased the crash odds by 6.0%.

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