Traffic Control under Pollutant Emissions Constraints

Most of the traditional taxi path planning studies assume that the aircraft is in uniform speed, and the model is optimized based on the shortest taxi time. Although it is easy to solve, it does not consider the change of the speed profile when the aircraft turns, and the optimal taxiing time of the aircraft does not necessarily bring the optimal taxiing fuel consumption. In this paper, the aircraft’s taxi distance and the number of turns in the taxi are considered. The aircraft path planning model with the shortest total distance of the airport surface is established. The improved A ∗ algorithm is used to obtain the shortest path P. Based on this, the shortest path P is established. Considering the multitarget velocity profile model of time and fuel consumption, a heuristic search is used to generate an accurate velocity profile for each path to obtain a 4D trajectory of the aircraft and then quantitative analysis of the impact of aircraft pollutant emissions on the airport environment based on 4D trajectory taxi time. The experimental results show that, compared with the traditional optimization method without considering the turning times, the total taxiing distance and turning times of the aircraft are greatly reduced. By balancing the taxiing time and fuel consumption, a set of Pareto-optimal velocity profiles is generated for the aircraft taxiing path; at the same time, it will help the airport save energy and reduce emissions and improve the quality of the airport environment. It has a high practical application value and is expected to be applied in the real-time air traffic control decision of aircraft surface in the future.

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CYCLING AT INTERSECTIONS: A MULTI-OBJECTIVE ASSESSMENT FOR TRAFFIC, EMISSIONS AND SAFETY

Transport ◽

10.3846/transport.2019.8946 ◽

2019 ◽

Vol 34 (3) ◽

pp. 225-236

Author(s):

Behnam Bahmankhah ◽

Paulo Fernandes ◽

Margarida C. Coelho

Keyword(s):

Traffic Control ◽

Objective Assessment ◽

Signalized Intersection ◽

Pollutant Emissions ◽

Motor Vehicles ◽

Specific Power ◽

Nsga Ii ◽

Traffic Performance ◽

Alternative Scenarios ◽

Demand Scenario

This paper evaluated in an integrated manner the traffic performance, pollutant emissions and road conflicts between bicycles and motor vehicles at a signalized intersection. Two alternative scenarios were examined: (1) bicycles increment and motor vehicles replacement within the cycle-fixed traffic signal; (2) replacing the existing traffic control by a conventional two-lane roundabout and evaluating the impacts of bicycles increment. For each scenario, bicycle demand was varied from 9 to 270 bicycles per hour (bph). Traffic flow and vehicle dynamic data were collected from a three-leg signalized intersection in Aveiro (Portugal). The microscopic traffic model (VISSIM) paired with an emission (Vehicle Specific Power – VSP) methodology and safety (Surrogate Safety Assessment Methodology – SSAM) model were used to assess intersection-specific operations. The fast Non-Dominated Sorting Genetic Algorithm (NSGA-II) was used to find the optimal bicycle demands. The results showed that two-lane roundabout outperformed the existing traffic control, namely in highest bicycle demand scenario (number of stops and travel time reduced in 78 and 14%, respectively; CO2, NOx, and HC decreased 9, 7, and 12%, respectively). It was also found that the number of conflicts was significantly reduced (–49%) with this latter layout even in maximum bicycle demand scenario (270 bph). However, roundabout layout lead to more severe conflicts and potential crashes. The analysis showed that bicycle demands of 75, 95 and 110 bph delivered good environmental and safety outcomes for the intersection.

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Investigating the Relationship between Controller Locations and Dynamic Traffic Control in Generic Transportation Networks

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198120914302 ◽

2020 ◽

Vol 2674 (5) ◽

pp. 172-182

Author(s):

Marco Rinaldi ◽

Francesco Viti

Keyword(s):

Traffic Control ◽

Urban Areas ◽

Traffic Management ◽

Dynamic Traffic Assignment ◽

Transportation Networks ◽

Generalization Test ◽

Real Life ◽

Pollutant Emissions ◽

Dynamic Traffic ◽

The Relationship

Traffic control policies aim at reducing the negative externalities that ever-growing demand is causing on transportation networks, such as congestion and pollutant emissions. To achieve these goals, strategies coordinating and aligning the effects of several individual traffic controllers have received increasing attention in research and development in the past decades. However, a considerable gap still exists between the desired and experienced performance of advanced dynamic traffic management systems, resulting in failure to completely prevent the increasing peak-hour congestion in main urban areas worldwide. In this work we contribute to assessing whether this gap might be tied to inefficient network design, rather than algorithmic prowess. Based upon our earlier work, we investigate whether a trend can be found between determining locations of controllers in a network following control theoretical insights, and try to confirm our earlier intuitions when dealing with dynamic traffic assignment, featuring accurate propagation and spillback dynamics. To achieve these goals, we extend an existing synthetic network generation tool to allow us to test this hypothesis on real-life-like road networks, and extend our previously developed algorithms for the controller location problems allowing for sufficient generalization. Test results are presented on a simpler deterministic scenario and on 240 randomly generated networks, showcasing that placing controllers following controllability-based principles is advantageous from the perspective of model-based dynamic traffic management applications.

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Workload Perception of Air Traffic Control Officers and Pilots During Continuous Descent Operations Approach Procedures

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000154 ◽

2019 ◽

Vol 9 (1) ◽

pp. 2-11

Author(s):

Marina Efthymiou ◽

Frank Fichert ◽

Olaf Lantzsch

Keyword(s):

Fuel Consumption ◽

Traffic Control ◽

Air Traffic Control ◽

Negative Impact ◽

Air Traffic ◽

Reduce Fuel Consumption ◽

Total Load ◽

Open Path

Abstract. The paper examines the workload perceived by air traffic control officers (ATCOs) and pilots during continuous descent operations (CDOs), applying closed- and open-path procedures. CDOs reduce fuel consumption and noise emissions. Therefore, they are supported by airports as well as airlines. However, their use often depends on pilots asking for CDOs and controllers giving approval and directions. An adapted NASA Total Load Index (TLX) was used to measure the workload perception of ATCOs and pilots when applying CDOs at selected European airports. The main finding is that ATCOs’ workload increased when giving both closed- and open-path CDOs, which may have a negative impact on their willingness to apply CDOs. The main problem reported by pilots was insufficient distance-to-go information provided by ATCOs. The workload change is important when considering the use of CDOs.

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How to Evaluate Remote Tower Metrics in Connection With Weather Observations

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000142 ◽

2018 ◽

Vol 8 (2) ◽

pp. 100-111 ◽

Cited By ~ 1

Author(s):

Maik Friedrich ◽

Christoph Möhlenbrink

Keyword(s):

Traffic Control ◽

Air Traffic Control ◽

Influential Factors ◽

Air Traffic ◽

Weather Event ◽

Evaluation Of Performance ◽

Weather Events ◽

Weather Observations ◽

Validation Experiment ◽

Remote Controller

Abstract. Owing to the different approaches for remote tower operation, a standardized set of indicators is needed to evaluate the technical implementations at a task performance level. One of the most influential factors for air traffic control is weather. This article describes the influence of weather metrics on remote tower operations and how to validate them against each other. Weather metrics are essential to the evaluation of different remote controller working positions. Therefore, weather metrics were identified as part of a validation at the Erfurt-Weimar Airport. Air traffic control officers observed weather events at the tower control working position and the remote control working position. The eight participating air traffic control officers answered time-synchronized questionnaires at both workplaces. The questionnaires addressed operationally relevant weather events in the aerodrome. The validation experiment targeted the air traffic control officer’s ability to categorize and judge the same weather event at different workplaces. The results show the potential of standardized indicators for the evaluation of performance and the importance of weather metrics in relation to other evaluation metrics.

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