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


Publications ENAC - Mardi, 1 août 2017 - 12:23:56
In the air transportation system, airports are connected by companies operating flights in different ways. One is to use a shuttle system, with a high number of evenly scheduled daily flights. In such a case, a delay occurring will be smoothed out using the buffer effect of the remaining rotating flights. On the other hand, companies operating a single rotation will only be able to mitigate the delay using the turnaround duration. It is the same for transit flights. In existing simulation environments, such a fine structure is not taken into account, even if some tools were designed in the context of rail transportation. The purpose of the present work is to provide the...

[tel-01570242] Architecture de communication sécurisée d’une flotte de drones

Publications ENAC - Lundi, 31 juillet 2017 - 20:01:59
Grâce aux progrès de miniaturisation des systèmes embarqués, les mini-drones qu’on appelle en anglais Small Unmanned Aerial Vehicle (UAVs) sont apparus et permettent de réaliser des applications civiles à moindres coûts. Pour améliorer leurs performances sur des missions complexes (par exemple, pour contourner un obstacle), il est possible de déployer une flotte de drones coopératifs afin de partager les tâches entre les drones. Ce type d’opération exige un niveau élevé de coopération entre les drones et la station de contrôle. La communication entre les drones de la flotte est donc un enjeu important dans la réalisation des opérations d’une flotte de drones. Parmi les...

[hal-01567619] Next-generation Computer-aided Composition Environment: A New Implementation of OpenMusic

Publications ENAC - Vendredi, 28 juillet 2017 - 03:11:08
O7 is a new implementation of the OpenMusic computer-aided composition environment. This paper gives a general presentation of its visual programming framework, musical structures, and in-built graphical editors. It also describes embedded features for the interactive and dynamic execution of musical processes, and for digital signal processing.

[hal-01469783] Interactive exploration of 3D scanned baggage

Publications ENAC - Jeudi, 27 juillet 2017 - 03:12:08
An interactive visualization system can support volumetric data exploration in airport security screenings by addressing the challenges unique to the baggage inspection. The proposed system includes a set of interaction techniques that combine the direct manipulation of voxels and their interactive visualization. The system's final tools and GUI design incorporate feedback from airport personnel and were validated by real-world users in terms of effectiveness and ease of use.

[hal-01522033] Dynamic airspace configuration by genetic algorithm

Publications ENAC - Mercredi, 26 juillet 2017 - 17:36:53
With the continuous air traffic growth and limits of resources, there is a need for reducing the congestion of the airspace systems. Nowadays, several projects are launched, aimed at modernizing the global air transportation system and air traffic management. In recent years, special interest has been paid to the solution of the dynamic airspace configuration problem. Airspace sector configurations need to be dynamically adjusted to provide maximum efficiency and flexibility in response to changing weather and traffic conditions. The main objective of this work is to automatically adapt the airspace configurations according to the evolution of traffic. In order to reach...

[hal-01478322] Hybrid metaheuristic for air traffic management with uncertainty

Publications ENAC - Mardi, 25 juillet 2017 - 20:01:43
To sustain the rapidly increasing air traffic demand, the future air traffic management system will rely on a concept, called Trajectory-Based Operations (TBO), that will require aircraft to follow an assigned 4D trajectory (time-constrained trajectory) with high precision. TBO involves separating aircraft via strategic (long-term) trajectory deconfliction rather than the currently-practicing tactical (short-term) conflict resolution. In this context, this chapter presents a strategic trajectory planning approach aiming at minimizing the number of conflicts between aircraft trajectories for a given day. The proposed methodology allocates an alternative departure time, a...

[hal-01565168] Mental workload and neural efficiency quantified in the prefrontal cortex using fNIRS

Publications ENAC - Samedi, 22 juillet 2017 - 03:12:14
An improved understanding of how the brain allocates mental resources as a function of task difficulty is critical for enhancing human performance. Functional near infrared spectroscopy (fNIRS) is a fielddeployable optical brain monitoring technology that provides a direct measure of cerebral blood flow in response to cognitive activity. We found that fNIRS was sensitive to variations in task difficulty in both real-life (flight simulator) and laboratory settings (tests measuring executive functions), showing increased concentration of oxygenated hemoglobin (HbO2) and decreased concentration of deoxygenated hemoglobin (HHb) in the prefrontal cortex as the tasks became...

[hal-01533755] FFTEB: Edge Bundling of Huge Graphs by the Fast Fourier Transform

Publications ENAC - Jeudi, 20 juillet 2017 - 19:29:11
Edge bundling techniques provide a visual simplification of cluttered \ graph drawings or trail sets. While many bundling techniques exist, \ only few recent ones can handle large datasets and also allow selective \ bundling based on edge attributes. We present a new technique \ that improves on both above points, in terms of increasing both the \ scalability and computational speed of bundling, while keeping the \ quality of the results on par with state-of-the-art techniques. For \ this, we shift the bundling process from the image space to the spectral \ (frequency) space, thereby increasing computational speed. We \ address scalability by proposing a data streaming...

[hal-01559020] State of the Art in Edge and Trail Bundling Techniques

Publications ENAC - Mardi, 18 juillet 2017 - 14:27:27
Bundling techniques provide a visual simplification of a graph drawing or trail set, by spatially grouping similar graph edges or trails. This way, the structure of the visualization becomes simpler and thereby easier to comprehend in terms of assessing relations that are encoded by such paths, such as finding groups of strongly interrelated nodes in a graph, finding connections between spatial regions on a map linked by a number of vehicle trails, or discerning the motion structure of a set of objects by analyzing their paths. In this state of the art report, we aim to improve the understanding of graph and trail bundling via the following main contributions. First, we...

[hal-01557327] Taming Mismatches in Inter-Agent Distances for the Formation-Motion Control of Second-Order Agents

Publications ENAC - Vendredi, 7 juillet 2017 - 19:53:22
This paper presents the analysis on the influence of distance mismatches on the standard gradient-based rigid formation control for second-order agents. It is shown that, similar to the first-order case as recently discussed in the literature, these mismatches introduce two undesired group behaviors: a distorted final shape and a steady-state motion of the group formation. We show that such undesired behaviors can be eliminated by combining the standard formation control law with distributed estimators. Finally, we show how the mismatches can be effectively employed as design parameters in order to control a combined translational and rotational motion of the formation.
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