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Fast Marching Tree applied to geodesic trajectories in presence of wind: a day of flights in Europe study
No full textThis paper addresses the generation of aircraft cruise optimal trajectories in the presence of wind using FMT* algorithm. After presenting the problem handled, the adaptation of the algorithm to solve it are presented. In particular, how to deal with great circle distances without increasing too much the computation time is detailed. The proposed method is evaluated on benchmarks and is shown as appropriate to solve this problem. A case study on European flights is also given. This case study shows that this method obtains good results on most European origin-destination pairs. This work is a preliminary work to show that FMT* can be used for aircraft cruise trajectories planning in the presence of wind
Design orienté collaboration à distance pour supporter la mutual awareness dans le cadre du Single-Pilot Operation
No full textIHM'23 - 34e Conférence Internationale Francophone sur l'Interaction Humain-MachineAFIHM, Université de Technologie de TroyesInternational audienceFor economic reasons, manufacturers have been considering dedicating commercial flights to a single pilot for the last ten years. In order to ensure a certain redundancy, this pilot could be assisted by a ground pilot. In the absence of appropriate collaboration tools, the physical separation of these pilots will lead to a degradation of the mutual understanding of behaviors (observable fact on a person) and activities (i.e. mutual awareness). In order to restore mutual awareness, indicators of each pilot’s behavior (i.e. design element) need to be integrated into future flight tools. In this paper, we study the modalities of design elements in two new interfaces (ground and onboard) developed by iterations. These collaborative interfaces contain two types of elements: a remote display of the pilot’s eye movements, via an eye-tracking system, and an indicator of the activities performed in the tool (moving in the map, navigation in the tabs). Two remote collaboration scenarios were proposed to four professional pilots. They allowed to identify the cues to be transmitted, such as the availability of the pilots, and to test the transmission modalities: capture (eye-tracking, audio, interface inputs), temporality (continuous transmission) and representation (graphic, audio).Depuis une dizaine d’années, pour des raisons économiques, les industriels envisagent de dédier la conduite des vols commerciaux à un pilote unique. Afin d’assurer une certaine redondance, ce dernier serait possiblement assisté par un pilote au sol. En l’absence d’outils de collaboration appropriés, la séparation physique de ces pilotes conduira à une dégradation de la compréhension mutuelle des comportements (fait observable sur une personne) et activités (i.e. mutual awareness). Afin de rétablir la mutual awareness, des indicateurs sur le comportement et les activités de chaque pilote (i.e. éléments de design) doivent être intégrés dans les futurs outils de vol. Dans cet article, nous étudions les modalités des éléments de design dans deux nouvelles interfaces (sol et bord) développées par itérations. Ces interfaces collaboratives contiennent deux types d’élément : un affichage à distance des mouvements oculaires du pilote, via un système d’eye-tracking, et un indicateur des activités effectuées dans l’outil (déplacement dans la carte, navigation dans les onglets). Deux mises en situation de collaboration à distance ont été proposées à quatre pilotes professionnels. Elles ont permis d’identifier les indices à transmettre, tels que la disponibilité des pilotes, et de tester les modalités de transmission : capture (eye-tracking, audio, entrées d’interface), temporalité (transmission continue) et représentation (graphique, audio)
Optimisation d'un ensemble de routes aériennes pour minimiser l'impact environnemental des traînées de condensation
No full textInternational audienc
Dynamique de la construction de la perception auditive consciente : Aspects électrophysiologiques et corrélats informationnels neuronaux
No full textIn some operational situations in aeronautics, a pilot may not perceive an audible alarm even though it is well above the detection threshold, thus creating a significant risk for the safety of air operations. Detecting an auditory target of interest is a phenomenon of conscious auditory perception, based on an analysis of the auditory scene. Currently, a major challenge is to be able to assist in the diagnosis and prediction of the conscious access and its construction dynamics by means of physiological markers. In order to provide neurofeedbacks to pilots in future neurocockpits, it is necessary to characterize perception at behavioral and electrophysiological levels. The objective of this thesis was therefore to study the relevance of some indicators of brain activity properties in the characterization of conscious auditory perception. This work sought to characterize the dynamics of the construction of conscious auditory perception through behavioral, electrophysiological and macroscopic neural informational correlates. To achieve this, we studied auditory perceptual awareness in healthy adult humans based on experimental psychology and electroencephalography experiments in an informational masking situation. We conducted two experimental studies, one behavioral and the other electrophysiological. The first study allowed us to show that it is possible: i) to study the influence of stimulus factors on the construction of perceptual awareness dynamics in informational masking specifically using time-to-event data analysis models (or survival data models); and ii) to use specific combinations of auditory stimulus factors to "tune" these dynamics and allow the examination of underlying cognitive and neural processes. Using these combinations, the second study allowed us to show: (i) a reproduction of the neural correlates of event-related potentials from the literature of conscious auditory perception in informational masking; and that, conscious auditory perception leads to (ii) a modification of the information content and complexity of the neural signal; (iii) a modification of information transmission patterns within brain networks with notably the presence of a posterior parietal informational center to which information is directed and finally (iv) an increase in information integration within auditory cortices. Several indicators resulting from this work could be used to characterize the conscious access of an auditory target and thus bring solutions to the problem of the absence of perception of the sound alarm by a pilot.Dans le cadre de situations opérationnelles en aéronautique, un pilote peut ne pas percevoir une alarme sonore pourtant bien au-dessus du seuil de détection, engendrant ainsi un risque important pour la sécurité des opérations aériennes. Détecter une cible auditive d’intérêt représente un phénomène de perception auditive consciente, basé sur une analyse de la scène auditive. Actuellement, un défi majeur consiste à pouvoir aider au diagnostic et à la prédiction de l’accès conscient et à la dynamique de sa construction au moyen de marqueurs physiologiques. En vue de fournir des neurofeedbacks aux pilotes dans les futurs neuro-cockpits, il est nécessaire de caractériser la perception à des niveaux comportementaux et électrophysiologiques. L’objectif de cette thèse a donc été d’étudier la pertinence de certains indicateurs des propriétés de l’activité cérébrale dans la caractérisation de la perception auditive consciente. Ce travail a cherché à caractériser la dynamique de la construction de la perception auditive consciente à travers des aspects comportementaux, électrophysiologiques et des corrélats informationnels neuronaux macroscopiques. Pour y parvenir, nous avons étudié la conscience perceptive auditive chez l’être humain adulte sain sur la base d’expérimentations de psychologie expérimentale et d’électroencéphalographie dans une situation de masquage informationnel. Nous avons réalisé deux études expérimentales, l’une comportementale et l’autre électrophysiologique. La première étude nous a permis de montrer qu’il est possible : i) d’étudier l’influence de facteurs du stimulus sur la construction de la dynamique de la conscience perceptive dans le masquage informationnel spécifiquement à l’aide de modèles d’analyse de données de temps à l’évènement (ou modèles de données de survie) ; et ii) d’utiliser des combinaisons spécifiques de facteurs du stimulus auditif afin de « régler » cette dynamique et de permettre l’examen des processus cognitifs et neuronaux sous-jacents. En utilisant ces combinaisons, la seconde étude nous a permis de montrer : i) une reproduction des corrélats neuronaux de potentiels liés à l’évènement issus de la littérature de la perception auditive consciente dans le masquage informationnel ; et que, la perception auditive consciente entraîne ii) une modification du contenu en information et en complexité du signal neuronal ; iii) une modification des patterns de transmission de l’information au sein de réseaux cérébraux avec notamment la présence d’un centre informationnel pariétal postérieur vers lequel se dirige de l’information et enfin iv) une hausse de l’intégration de l’information au sein des cortex auditifs. Plusieurs indicateurs issus de ce travail pourront être utilisés pour caractériser l’accès conscient d’une cible auditive et ainsi apporter des solutions au problème de l’absence de perception de l’alarme sonore par un pilote
An adapted Fast Marching Tree for contrails mitigation: A short-and long-range flight study
No full textInternational audienceThis paper addresses the problem of finding a trajectory for an aircraft minimizing its total environmental impact. In particular, CO2 and contrails are considered. The Fast Marching Tree method is known to be efficient to find trajectories avoiding obstacles. This method is adapted to the case of soft obstacles, here areas favorable to contrails. This study is done in 2D and for the cruise phase of airliners. Two case studies on short-and long-haul flights are presented. The given results show trajectories minimizing the overall impact according to the given metric by trading off between CO2 and contrails. Moreover, they are obtained with a low computation time allowing one to consider extensions. Finally, an improvement concerning the sampling is proposed, reducing the computation time and cost
Mixed-integer nonlinear and continuous optimization formulations for aircraft conflict avoidance via heading and speed deviations
No full textInternational audienceWe introduce two new optimization models for the aircraft conflict avoidance problem that aims at issuing decisions on both speed and heading-angle deviations to keep aircraft pairwise separated by a given separation distance. The first model is a new mixed-integer nonlinear formulation. The second model is a continuous optimization formulation, less typical in aircraft conflict avoidance. The advantages of the two models are combined within a three-phase method that we propose to solve the problem to global optimality. Computational experiments on various instances from the literature yield very promising results, and show the effectiveness of the proposed models and of the three-phase solution approach
The continuous quadrant penalty formulation of logical constraints
No full textInternational audienceCould continuous optimization address efficiently logical constraints? We propose a continuous-optimization alternative to the usual discrete-optimization (big-M and complementary) formulations of logical constraints, that can lead to effective practical methods. Based on the simple idea of guiding the search of a continuous-optimization descent method towards the parts of the domain where the logical constraint is satisfied, we introduce a smooth penalty-function formulation of logical constraints, and related theoretical results. This formulation allows a direct use of state-of-the-art continuous optimization solvers. The effectiveness of the continuous quadrant penalty formulation is demonstrated on an aircraft conflict avoidance application
Why and when do you look away when trying to remember? Gaze aversion as a marker of the attentional switch to the internal world during memory retrieval
No full textInternational audienceIt is common to look away while trying to remember specific information, for example during autobiographical memory retrieval, a behavior referred to as gaze aversion. Given the competition between internal and external attention, gaze aversion is assumed to play a role in visual decoupling, i.e., suppressing environmental distractors during internal tasks. This suggests a link between gaze aversion and the attentional switch from the outside world to a temporary internal mental space that takes place during the initial stage of memory retrieval, but this assumption has never been verified so far. We designed a protocol where 33 participants answered 48 autobiographical questions while their eye movements were recorded with an eye-tracker and a camcorder. Results indicated that gaze aversion occurred early (median 1.09 s) and predominantly during the access phase of memory retrieval-i.e., the moment when the attentional switch is assumed to take place. In addition, gaze aversion lasted a relatively long time (on average 6 s), and was notably decoupled from concurrent head movements. These results support a role of gaze aversion in perceptual decoupling. Gaze aversion was also related to higher retrieval effort and was rare during memories which came spontaneously to mind. This suggests that gaze aversion might be required only when cognitive effort is required to switch the attention toward the internal world to help retrieving hard-to-access memories. Compared to eye vergence, another visual decoupling strategy, the association with the attentional switch seemed specific to gaze aversion. Our results provide for the first time several arguments supporting the hypothesis that gaze aversion is related to the attentional switch from the outside world to memory
Understanding the Indirect Effects of Interactive Systems Within Systems of Systems
No full textInternational audienceUntil recently, research into the sustainable design of interactive systems has primarily focused on the direct material impact of a system, through improving its energy efficiency and optimizing its lifecycle. Yet the way a system is designed and marketed often has wider repercussions, such as rebound effects, and systemic change in practices. These effects are harder to assess (and to anticipate) than the direct physical impact of the construction and use of the system itself. Current tools are unable to account for the complexity of these effects: the underlying causal mechanisms, their multi‐level nature, their different temporalities, and the variety of their consequences (environmental and societal). This is why we are seeking to develop a specific methodology and tool, inspired by systemic design and system dynamics. These are intended for decision‐makers and designers of interactive systems within systems of systems (for example, in the fields of agricultural robotics or public transportation). In this paper, we present this modeling approach and our prototype tool through the example of a second‐hand clothing sales platform
Outil d'aide à la décision combinant simulation et optimisation pour l'allocation du personnel de sûreté aéroportuaire.
No full textInternational audienceAirport access mode disruptions have a significant impact on passenger arrival flow. Such events can lead to a wave of late outbound passengers, that can congest airport facilities such as check-in counters or security systems. In this context, efficient handling of airport resources is crucial to ensure passengers' reliable door-to-door journeys and maintain a high airport Level-of Service. Through a simulation-optimisation-based decision support system, we investigate the relevance of a dynamic opening of fast security line facilities for delayed passengers. An optimisation model solved through simulated annealing is proposed to improve security resource handling at a tactical level. Airport's Level of Service is evaluated before and after optimisation through a microscopic passenger flow simulation model. The methodology is tested on a study case based on one of the terminal buildings of Mexico-City airport. Results indicate that using dedicated security lines for passengers in a hurry due to disruptions reduces the number of stranded passengers at the end of the day; out of the three scenarios evaluated the one that uses a dynamic management of resources provides the best results; however this task should be governed by a DSS that adapts to the particular case under study