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Toutes les publications de l'ENAC en direct.
All ENAC publications.

[hal-01658676] Improving Airport Performance Through a Model-Based Analysis and Optimization Approach

Publications ENAC - Vendredi, 8 décembre 2017 - 17:38:43
Traditionally airport systems have been studied using an approach in which the different elements of the system are studied independently. Until recently scientific community has put attention in developing models and techniques that study the system using holistic approaches for understanding cause and effect relationships of the integral system. This chapter presents a case of an airport in which the authors have implemented an approach for improving the turnaround time of the operation. The novelty of the approach is that it uses a combination of simulation, parameter analysis and optimization for getting to the best amount of vehicles that minimize the turnaround...

[hal-01658763] A down to earth solution: applying a robust simulation-optimization approach to resolve aviation problems

Publications ENAC - Vendredi, 8 décembre 2017 - 16:03:16
This paper deals with the improvement of the robustness of heuristic solutions for aviation systems affected by uncertainty when the resolution of conflicts is implemented. A framework that includes the use of optimization and simulation is described which in turn generates pseudo-optimal schedules. The initial solution is progressively improved by iteratively evaluating the uncertainty in the generated solutions and calibrating in accordance with the objective function. Simulation is used for testing the feasibility of a solution generated by an optimization algorithm in an environment characterized by uncertainty. The results show that the methodology is able to...

[hal-01658238] Reconfigurable Grounded Vector Antenna for 3D Electromagnetic Direction Finding Applications

Publications ENAC - Jeudi, 7 décembre 2017 - 19:11:31
In this letter, a reconfigurable grounded wideband antenna is proposed in view of vector sensor applications. This antenna combines two orthogonal and colocated semi-circular arrays of Vivaldi antennas mounted over a metallic support. The radiation patterns of two wideband magnetic dipoles and one wideband electric dipole can be synthesized thanks to an appropriate antenna excitation. Measurement results are in good agreement with the simulated results obtained from full-wave electromagnetic simulations. The proposed antenna exhibits stable radiation patterns over a wide impedance bandwidth of 1.69:1, a high radiation efficiency and a good isolation between the antenna...

[hal-01655747] A Trajectory Clustering Framework to Analyse Air Traffic Flows

Publications ENAC - Jeudi, 7 décembre 2017 - 11:20:53
This paper describes a framework to automatically identify air traffic flows from a set of trajectories by using a clustering algorithm. The framework offers two methods to cluster trajectories, each one using a different distance/similarity measure between trajectories. Results and performance characteristics of both methods are compared by applying them to real trajectories over a French Area Control Center. The framework can output statistics and figures for flow analysis and its use is facilitated by the relatively low number of parameters to be provided by the user. Its aim is to help support the SESAR vision of flow-centric operations by being integrated into Air...

[hal-01652044] Simulated Annealing for Strategic Traffic Deconfliction by Subliminal Speed Control under Wind Uncertainties

Publications ENAC - Lundi, 4 décembre 2017 - 12:36:39
This paper introduces an algorithm that minimises conflicts between aircraft at the strategic level taking into account uncertainties on aircraft position due to errors into wind forecast. The strategy relies on subliminal speed control. Owing to the complexity of this kind of optimisation problem, a simulated annealing metaheuristic approach is employed. A scenario with four hours of traffic overflying the Spanish (structured, continental) airspace has been selected. Traffic has been retrieved from NEST Eurocontrol database with the corresponding wind ensemble probabilistic forecasts from the European Centre for Medium-Range Weather Forecasts. Due to uncertainties and...

[hal-01652047] Assessing ATM Performance with Simulation and Optimisation Tools The APACHE Project

Publications ENAC - Jeudi, 30 novembre 2017 - 18:33:10
This paper describes the objectives and methodology of the APACHE project, a SESAR Exploratory Research project proposing a new framework to assess European air traffic management (ATM) performance. This framework integrates an ATM simulator prototype used to synthesise scenarios for pre-ops performance assessment, but also needed to compute some novel performance indicators, which require from optimisation or simulation capabilities. This simulator embeds a trajectory planner; an airspace planner; a traffic and capacity planner; and finally, a performance analyser module. An illustrative example is given, showing the successful integration of all these modules, where an...

[hal-01652041] Short-term 4D Trajectory Prediction Using Machine Learning Methods

Publications ENAC - Jeudi, 30 novembre 2017 - 18:32:39
4D trajectory prediction is the core element of future air transportation system, which is intended to improve the operational ability and the predictability of air traffic. In this paper, we introduce a novel model to address the short-term trajectory prediction problem in Terminal Manoeuvring Area (TMA) by application of machine learning methods. It consists of two parts: clustering-based preprocessing part and Multi-cells Neural Network (MCNN)-based machine learning part. First, in the preprocessing part, Principle Component Analysis (PCA) is applied to the real 4D trajectory dataset for reducing the vector variable dimensions. Then, the trajectories are clustered...

[hal-01652046] Analysis of a Workload Model Learned from Past Sector Operations

Publications ENAC - Jeudi, 30 novembre 2017 - 18:32:57
In this paper, we assess the performance of a workload model trained on a subset of sectors, focusing on how it generalizes on fresh sectors. The model of the air traffic controller workload is learned from historical data made of workload mesurements extracted from past sector operations and ATC complexity measurements computed from radar records and airspace data (sector geometry). The workload is assumed to be low when a given sector is collapsed with other sectors into a larger sector, normal when it is operated as is, and high when it is split into smaller sectors assigned to several working positions. This learning problem is modeled as a classification problem...

[hal-01652303] Contrôle de congestion et gestion du trafic à partir de mesures Application pour l'optimisation de la qualité de service dans l'Internet

Publications ENAC - Jeudi, 30 novembre 2017 - 16:45:48
La métrologie n'est appliquée dans la recherche, l'ingénierie et la conception des réseaux Internet que depuis le début des années 2000, mais cette approche est de plus en plus populaire et tend à se généraliser. Ses principes consistent à étudier, caractériser, analyser et modéliser le trafic existant sur les liens de l'Internet, afin de comprendre les principes qui régissent le comportement du réseau par rapport à un trafic qui s'avère encore méconnu. En particulier, garantir la qualité de service (QdS) dans l'Internet est un problème essentiel aujourd'hui. La métrologie du trafic Internet, et notamment son analyse montre que les mécanismes de transport actuels (TCP)...

[hal-01271970] Use of a FishEye Camera for GNSS NLOS Exclusion and Characterization in Urban Environments

Publications ENAC - Jeudi, 30 novembre 2017 - 13:08:18
This article presents a new integration method for GNSS, INS and a fish-eye camera for improving vehicle navigation accuracy in urban environments. In general, the quality of satellite navigation systems in cities tends to be quite poor. The influence of multipath, masking and Non-Line-of-Sight (NLOS) signals can degrade the GNSS position accuracy up to tens of meters, making the solution quite unusable for precise applications. In this article, it is proposed to integrate a wide field-ofview fish-eye camera, mounted on the roof of the car and facing up. This camera is used to detect which satellites are in direct Line-of-Sight (LOS), and which are hidden behind...
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