Effect of Distance between Ramp and Upstream Signal on Ramp Meter Operation

2020 ◽  
Vol 02 (02) ◽  
pp. 43-49
Author(s):  
Khaled Shaaban ◽  
Muhammad Asif Khan ◽  
Ridha Hamila
Keyword(s):  
Traffic Signal ◽  
Ramp Metering ◽  
Control Logic ◽  
Freeway Traffic ◽  
Signal Coordination ◽  
The Impact ◽  
Ramp Control

Ramp metering is typically proposed as a responsive strategy that takes freeway traffic parameters as control inputs to the ramp control logic. Such a strategy can be implemented in two ways; isolated ramp control or coordinated ramp control. Coordinated ramp control typically involves the cooperation between several ramp meters connected to a freeway segment to manage traffic on the freeway and traffic all ramps. Few studies also proposed the coordination between the on-ramp and the upstream traffic signal. Such coordination can help to mitigate congestion on the freeway and to avoid queue formation at the on-ramp. In this study, the authors' previous work on ramp metering and upstream signal coordination was extended to further evaluate the performance of such schemes by considering the impact of the distance between the upstream traffic signal and freeway. Extensive simulations in SUMO were performed to evaluate the benefit of the proposed coordinated strategy and the impact of ramp distance on the effectiveness of such coordination.

scholarly journals Assessment of the impact of speed limit reduction and traffic signal coordination on vehicle emissions using an integrated approach

2011 ◽  
Vol 16 (7) ◽  
pp. 504-508 ◽  
Author(s):  
Madhava Madireddy ◽  
Bert De Coensel ◽  
Arnaud Can ◽  
Bart Degraeuwe ◽  
Bart Beusen ◽  
...  
Keyword(s):  
Vehicle Emissions ◽  
Integrated Approach ◽  
Traffic Signal ◽  
Speed Limit ◽  
Signal Coordination ◽  
The Impact

Integrated Traffic Signal Control Along Corridors With Multiple Intersections Near Highway-Rail Grade Crossings

2013 ◽  
Author(s):  
Yifeng Chen ◽  
Laurence R. Rilett
Keyword(s):  
Traffic Control ◽  
Traffic Signals ◽  
Traffic Signal ◽  
Railway Track ◽  
Test Bed ◽  
Control Logic ◽  
Grade Crossings ◽  
The Impact ◽  
Multiple Intersections ◽  
Near Highway

Traffic signal optimization for traffic signals located near highway-rail grade crossings (HRGC) can be difficult because of the complex nature of the interactions between the two systems and the necessity of considering multiple objectives, such as safety and operational efficiency. The problems are magnified when considering traffic control for corridors that have multiple intersections located near HRGCs. This paper develops a methodology for optimizing traffic signals along a highway-railway corridor while considering the dual objectives of maximizing safety and efficiency. The Highway 6 (Cornhusker Hwy) corridor in Lincoln, Nebraska was used as a test bed. The corridor was modeled in VISSIM, and was used to emulate the traffic control along Highway 6, including the preemption logic. The traffic control logic was modeled using the Vehicle Actuated Programming (VAP) in the VISSIM simulation model. In addition, the logic allows multiple train events on the railway track that runs parallel to Highway 6 to be modeled. The model was calibrated to local traffic conditions using empirical field data. The impact of train frequency, length, direction, speed, etc., on the performance of the network and pedestrian safety will be evaluated.

scholarly journals REDUCING A POSSIBILITY OF TRANSPORT CONGESTION ON FREEWAYS USING RAMP CONTROL MANAGEMENT

Transport ◽  
2017 ◽  
Vol 32 (3) ◽  
pp. 314-320 ◽  
Author(s):  
Roman Lagerev ◽  
Denis Kapski ◽  
Marija Burinskienė ◽  
Andrius Barauskas
Keyword(s):  
Road Safety ◽  
Demand Management ◽  
Ramp Metering ◽  
Lane Changes ◽  
Traffic Conditions ◽  
Access Control Management ◽  
The Impact ◽  
Ramp Control ◽  
Control Management

Merge junctions are the key elements in the freeway system, as they are likely to function as bottlenecks. Investigations into breakdown occurrence at ramp junctions have demonstrated that when the groups of several vehicles following each other enter the freeway from the ramp, they are expected to create ‘turbulence’ resulting from lane changes, decelerations of vehicles on the mainline and inevitably by the cars merging from the on-ramp. This turbulence can lead to breakdown when the level of mainline demand is adequately high. In other words, the impact of a ramp vehicle on capacity is higher than that of a mainline vehicle, which indicates that a part of vehicles will simultaneously occupy two lanes during the process of changing them thus momentarily decreasing the capacity of the link. This feature becomes particularly important near bottlenecks where it might reduce the already limited throughput. The article introduces the main approaches, methodology, principles and stages of transport demand management on freeways that are aimed at improving the operation quality of transport facilities, including road safety. The technique allows evaluating and optimizing a Ramp-Metering (RM) concept from the viewpoint of minimizing the length of queues on ramps and a possibility of transport congestion. The proposed algorithm estimates the probability of starting congestion formation on the ramp using objective information on traffic conditions in each segment of the highway, which is based on the criterion for vehicle density on the lane. The last chapter shows the examples of traffic flow optimization on Western bypass ramps in Vilnius comparing two strategies for access control management using one or several vehicles per lane. Conclusions, trends and work on future investigations are presented at the end of the article.

The Effect of the Color of a Long Cane Used by Individuals who Are Visually Impaired on the Yielding Behavior of Drivers

2017 ◽  
Vol 111 (5) ◽  
pp. 401-410
Author(s):  
Eugene A. Bourquin ◽  
Robert Wall Emerson ◽  
Dona Sauerburger ◽  
Janet Barlow
Keyword(s):  
Visually Impaired ◽  
Low Vision ◽  
Visual Impairments ◽  
Substantial Effect ◽  
Traffic Signal ◽  
Driver Response ◽  
Yielding Behavior ◽  
White Cane ◽  
The Impact ◽  
Cane Technique

Introduction A new market trend offers long canes for individuals with visual impairments in a variety of colors; however, the impact of these colors is unknown to orientation and mobility (O&M) specialists and individuals who are blind or who have low vision. The authors examined the impact of cane color on drivers’ yielding behaviors; also, cane display effectiveness was assessed. Methods At traffic signal–controlled intersections, drivers’ yielding responses (yield–no yield and seconds to crosswalk) were recorded by two raters when a pedestrian presented one of two conditions (display and flagging) with four differently colored long canes (white, black, yellow, and green). Results In trials where the pedestrian used a flagging cane technique, the white cane achieved 290% more yielding than the green cane, 100% more yielding than the yellow cane, and 40% more yielding than the black. Statistical differences were found between the white-with-red cane and the yellow and green canes. The measure of drivers’ latency for moving forward was not statistically different between trials in which a pedestrian displayed a white cane at the crosswalk and trials in which no pedestrians were present. Discussion Cane color appears to have a substantial effect on drivers’ yielding responses. The results also indicate only a slight driver response to a highly visible cane display, confirming the results of previous studies that recommended more potent pedestrian movements to mitigate the threat from turning vehicles. Implications for practitioners O&M specialists and cane travelers need to consider the options for cane color when using a cane to cross streets. A white cane, flagged at the onset of the walk signal, can achieve more desirable responses from drivers than can the long canes of other colors. More effective cane behaviors exhibited by pedestrians who are visually impaired should always be considered by O&M instructors in order to influence drivers.

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