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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Contribution à la commande du flux de trafic autoroutier / Contribution to the control of the motorway traffic flow

Dryankova, Vesela 12 December 2013 (has links)
Les avancées technologiques, dues à l’avènement des nouvelles technologies d’information etde communication, ont donné naissance au concept des Systèmes de Transport Intelligents (STI).Les objectifs de telles applications consistent à apporter des solutions efficaces pour faire face auxproblèmes quotidiens des phénomènes de congestion. L’importance ainsi que les enjeux socioéconomiquesposés par les congestions imposent d’introduire des solutions innovantes utilisantles avancées récentes dans le domaine de la commande. Les travaux présentés dans cette thèse sesituent dans le cadre des STI et traitent des problèmes de la commande du trafic autoroutier et surles Voies Rapides Urbaines (VRU). Parmi les techniques de commande utilisée, nos travaux se focalisentprincipalement sur le contrôle d’accès isolé. L’objectif d’une telle action de régulation estd’agir sur le débit des rampes d’entrée, via des feux de signalisation, afin de maintenir la densitésur la voie principale aux alentours d’un seuil critique permettant ainsi, une utilisation optimale del’infrastructure autoroutière ou des VRU. L’algorithme proposé repose sur l’utilisation conjointede la platitude différentielle et le concept de la commande par mode glissant d’ordre supérieur. Laprincipale caractéristique de la platitude réside dans sa capacité à assurer une génération de trajectoiressans intégration d’aucune équation différentielle du modèle étudié. L’intérêt de la commandepar mode glissant d’ordre supérieur est de permettre le suivi de trajectoires d’une manière robustemême en présence d’incertitudes et de perturbations typiques aux systèmes de trafic. La pertinencede l’approche proposée est validée via un ensemble de simulations avec des données réelles d’uneportion de l’autoroute A6 du périphérique de Paris. De plus, la validation a été enrichie par l’évaluationde performances basée sur des critères couramment utilisés par les exploitants. L’ensembledes résultats ouvre la voie à plusieurs perspectives d’amélioration et de généralisation de cettecommande à des réseaux routiers plus complexes. / The technological advances, due to the advent of the new information and communication technologieshave given rise to the Intelligent Transportation Systems (ITS) concept. The objectivesof such applications are to provide effective solutions to deal with the daily problems of congestion.The importance as well as the socio-economic challenges raised by congestion requires theintroduction of innovative solutions based on the latest advances in the automatic control field. Theworks presented in this thesis lie in the frame of ITS and treat the problems of the freeway andUrban Express Routes (UER) control. Among the used control techniques, our works focus mainlyon the isolated ramp metering. The objective of this control measurement is to act on the on-rampflow, through traffic lights, in order to keep the traffic density on the mainstream section around acritical threshold allowing then an optimal use of the freeway or UER infrastructures. The proposedalgorithm rests on the jointly use of differential flatness and high order sliding mode control(HOSMC) concept. The main characteristic of the differential flatness lies in its ability to providea trajectory generation, without integration of any differential equation of the studied model. Onthe other hand, the advantage of HOSMC is to allow a robust trajectory tracking even in the case ofthe presence of uncertainties and disturbances which are typical to traffic systems. The relevanceof the proposed approach is validated through a set of numerical simulations using real-data froma part of the A6 freeway from Paris ring. In addition, the validation step has been enriched by theperformance evaluation based on a set of criteria commonly used by the freeway practitioners. Theobtained results paves the way to several perspectives in order to improve the proposed controlapproach and its generalization for more complex freeway networks.
242

Évaluation d’un système de résolution de conflits, ERASMUS : apport de l’oculométrie comme mesure de la charge mentale chez les contrôleurs aériens en-route / Evaluation of an Automated Conflict Solver, ERASMUS : the contribution of eye-tracking as mental workload measurement on en-route air traffic controllers

Paubel, Pierre-Vincent 11 July 2011 (has links)
Le contrôle aérien doit faire face à une forte intensification du trafic aérien. Dans cette situation, la problématique de la charge mentale chez les contrôleurs aériens est une préoccupation majeure pour maintenir le niveau de sécurité actuel. Le système d’aide automatisé ERASMUS a été élaboré afin de réduire la charge mentale chez les contrôleurs aériens. L’objectif d’ERASMUS est de compenser les effets liés à l’intensification du trafic en réduisant de manière subliminale la charge mentale associée à l’augmentation des conflits potentiels. L’objectif principal de cette thèse est de proposer pour la première fois une mesure objective de l’impact du système d’aide ERASMUS sur la charge mentale des contrôleurs aériens. La réalisation de cet objectif a nécessité le développement d’une plateforme originale d’enregistrement et de traitement des mouvements oculaires non intrusive dans un environnement de simulation hautement fidèle. Les mouvements oculaires d’un groupe de contrôleurs aériens experts ont été enregistrés. En accord avec l’hypothèse d’ERASMUS, les résultats ont montré des effets de tailles moyennes à grandes sur l’amplitude des saccades, le temps moyen passé sur les aéronefs et sur la distribution de l’attention allouée à la scène visuelle. De plus, sans ERASMUS, l’augmentation de la densité du trafic a augmenté de manière significative les diamètres pupillaires. A l’opposé, quand ERASMUS est actif, l’intensification du trafic n’a pas impacté significativement les diamètres pupillaires. Nous discutons l’impact d’ERASMUS sur la charge mentale ainsi que l’utilisation des mesures oculométriques dans un environnement de simulation écologique de contrôle aérien. / Air Traffic Control has to handle the strong and constant increase in air traffic density. In this context, mental workload experienced by air traffic controllers is a key research concept to maintain the actual safety level. ERASMUS is an automated aid system designed to reduce air traffic controllers’ workload. The purpose of ERASMUS is to compensate the effects of the air traffic growth by reducing the increased mental workload associated with a greater number of potential conflicts. Prior experiments designed to validate the ERASMUS system showed a reduction in ratings of mental workload, but only subjectives measures were used. In the present thesis, the first goal is to complete these first results by providing, for the first time, a real time objective measure of controllers’ mental workload. In this purpose, we had to develop a new non-intrusive eye-tracking platform in a fully realistic simulation environment. The eye movements of seven controllers, placed in a high-fidelity simulation, were recorded. Traffic sequences were manipulated (with vs. without ERASMUS). Consistent with a reduced workload hypothesis, results showed medium to large effects of ERASMUS on the amplitude of saccades, on the time spent gazing aircraft, and on the distribution of attention over the visual scene. Moreover, without ERASMUS, growth in the traffic density significantly increased pupil diameters. In contrast, when ERASMUS was activated, traffic density growth did not impact significantly pupil diameters. Finally, we discuss the impact of ERASMUS on mental workload and the use of pupillometric measures in an ecological air traffic control environment.
243

Nejčastější příčiny chybovosti řídícího letového provozu při poskytování služeb ŘLP / The most frequent causes of air traffic controller errors in the process of providing ATS

Čeremetová, Erika January 2013 (has links)
In my Master´s thesis I am concerned with the questions of the human factor in air traffic control. The work is mainly focused on the air traffic controller and discusses the influences that directly or indirectly affect the air traffic controller. Considerable attention is paid to the errors that may occur during the management, their analysis and proposals for their elimination, respectively their complete disposal. The main idea is to understand the thinking of the air traffic controller as the human element in an organization and applying theories to reduce the errors in the air traffic control.
244

Flying is Dangerous - That is why it is so safe : Miscommunication in aviation

Thörnqvist, Christer January 2020 (has links)
In this essay one has been investigating some of the reasons why aviation incidents take place and also examine what strategies there are to minimize the risks - primarily regarding miscommunication which often seems to be a contributing element or a direct cause in aviation mishaps. The aim of this study is to highlight and raise awareness about this field of study from a communicative point of view.The study has been performed using qualitative interviews with pilots, Air Traffic Controllers and other professionals within the aviation industry. The research has been somewhat hampered by the outbreak of the COVID-19 pandemic but not to an extent that would have corrupted the findings.The key results have indicated that miscommunication still is a problem in the aviation industry, but less so on the local national stage than in a global perspective. Two particular occurrences that have been given extra attention are runway incursions and the use of Controller Pilot Data-Link Communications.One has established that there are technical systems available on the market to improve communication performance and that runway incursion is a problem that grows with the complexity of the airport environment. One has also been made aware of the fact that human factors can only be mitigated so far with technology. The principal question has been: How can Miscommunication in Aviation be reduced? / I denna uppsats har vi tittat på några av de bakomliggande orsakerna till att incidenter fortfarande sker inom trafikflyget samt undersökt vilka strategier som föreligger för att minimera dessa risker - primärt pga felkommunikation vilken ofta tenderar att vara en bakomliggande eller direkt utlösande faktor i flygolyckor. Syftet med denna studie är att uppmärksamma och öka medvetenheten om dessa fenomen från en kommunikativ synvinkel.Studien har genomförts medelst en kvalitativ intervjumetod med piloter, flygledare och andra initierade yrkesgrupper inom flygindustrin. Forskningen har hämmats något pga utbrottet av COVID-19 pandemin men inte i en sådan omfattning att resultatet har förvanskats.De huvudsakliga resultaten har indikerat att felkommunikation fortfarande är ett problem inom flygbranschen, men i en långt mindre omfattning på lokal nationell nivå än i ett globalt perspektiv. Två specifika företeelser som har getts extra uppmärksamhet är rullbaneintrång samt användandet av CPDLC (datalänk).Vi har konstaterat att det finns tekniska system på marknaden för att förbättra prestandan på kommunikationen samt att rullbaneintrång är ett problem som växer med flygplatsens storlek och komplexitetsgrad. Vi har också uppmärksammats på att den mänskliga faktorn endast delvis kan undanröjas med hjälp av teknologi. Den huvudsakliga fågeställningen har varit: Hur kan felkommunikation inom flyget reduceras
245

Nejčastější příčiny chybovosti řídícího letového provozu při poskytování služeb ŘLP / The most frequent causes of air traffic controller errors in the process of providing ATS

Čeremetová, Erika January 2014 (has links)
In my Master´s thesis I am concerned with the questions of the human factor in air traffic control. The work is mainly focused on the air traffic controller and discusses the influences that directly or indirectly affect the air traffic controller. Considerable attention is paid to the errors that may occur during the management, their analysis and proposals for their elimination, respectively their complete disposal. The main idea is to understand the thinking of the air traffic controller as the human element in an organization and applying theories to reduce the errors in the air traffic control.
246

Design und User Experience in der Flugsicherung – Assistenzsystem zur Fernüberwachung im Multi-Airport-Betrieb

Leitner, Rodney, Oehme, Astrid January 2016 (has links)
Die Flugsicherung in Europa befindet sich im Wandel, denn der Europäische Luftraum und die damit verbundenen Prozesse werden seit einigen Jahren harmonisiert. Eine Vielzahl der Forschungsprojekte, die diese Entwicklung begleiten, zielt darauf ab, eine orts- und außensichtunabhängige Arbeitsumgebung für Fluglotsen zu entwickeln. Insbesondere für kleinere Regionalflughäfen besteht die Idee, eine Fernüberwachung in einem Control Center zu bündeln, da die Fluglotsen bis auf die üblichen Peak-Zeiten häufig nicht ausgelastet und teilweise unterfordert sind. Dies ermöglicht nicht nur die Fernüberwachung eines Flughafens, sondern auch die gleichzeitige Überwachung und Kontrolle aller Flugbewegungen von mehreren Flughäfen. Neben den bisherigen Aufgaben eines Fluglotsen, wie das Überwachen des Verantwortungsbereichs und die Gewährleistung einer sicheren und zügigen Abwicklung des Flugplatzverkehrs, ist bei einer Mehrfachkontrolle (Multi-Airport-Control) die Planung des Verkehrsflusses auf den zu kontrollierenden Flughäfen von entscheidender Bedeutung. Neben Systemen zum Außensichtersatz ist hierbei daher auch ein System erforderlich, dass dem Fluglotsen bei der Planung der Flugbewegungen aller Flughäfen unterstützt. Unter Berücksichtigung eines nutzerzentrierten Ansatzes, Richtlinien für einfach bedienbare Benutzerschnittstellen und mit der Intention, auch im Arbeitskontext eine hohe User Experience (UX) zu bieten, wurde das Assistenzsystem MasterMAN entwickelt. Das Konstrukt der User Experience verfolgt einen ganzheitlichen Ansatz und beinhaltet nicht nur sachbezogene Aspekte wie die Usability des Systems sondern auch hedonische Aspekte wie Nutzeremotionen. Folglich wurde eine interaktive grafische Benutzeroberfläche gestaltet, die sowohl einen leichten und sicheren Umgang mit dem System als auch ein anspruchsvolles, positiv empfundenes Look and Feel gewährleistet. Bei der Evaluierung des Systems wurden neben der analytischen Inspektionsmethode Heuristische Evaluation nach Nielsen (1994) auch die ästhetischen Aspekte der grafischen Benutzerschnittstelle mit dem Fragebogen VisAWI (Visual Aesthetics of Websites Inventory) nach Thielsch & Moshagen (2014) adressiert. Acht Usability-Experten bewerteten das Assistenzsystem, notierten alle Auffälligkeiten und Usability-Probleme und führten ein dazugehöriges Severity Rating durch. Unter Zuhilfenahme dieser Vorgehensweise wurden insgesamt 56 Probleme identifiziert, die im weiteren Verlauf der Entwicklung korrigiert wurden. In einer abschließenden Gruppendiskussion mit allen Evaluatoren und den Entwicklern wurden nach dem Vorbild des Pluralistic Walkthrough die Probleme besprochen und Lösungsansätze mit den Usability-Experten erarbeitet. Hinsichtlich der ästhetischen Gestaltung der Benutzerschnittstelle ergab die VisAWIBewertung ein überdurchschnittliches Ergebnis und bestätigte damit ein ansprechendes Design. Weitere Untersuchungen zur Zufriedenheit von Fluglotsen beim Umgang mit dem System sind geplant.
247

Development of Optimization and Simulation Models for the Analysis of Airfield Operations

Baik, Hojong 12 July 2000 (has links)
This research is concerned with the modeling and development of algorithmic approaches for solving airport operational problems that arise in Air Traffic Control (ATC) systems within the terminal area at hub airports. Specifically, the problems addressed include the Aircraft Sequencing Problem (ASP) for runway operations, the Network Assignment Problem (NAP) for taxiway operations, and a simulation model for the evaluation of current or proposed ATC system in detail. For the ASP, we develop a mathematical model and apply the Reformulation-Linearization-Technique (RLT) of Sherali and Adams to construct an enhanced tightened version of the proposed model. Since ASP is NP-Hard and in fact, it is a variation of the well-known Traveling Salesman Problem with time-windows, sub-optimal solutions are usually derived to accommodate the real-time constraints of ATC systems. Nevertheless, we exhibit a significant advancement in this challenging class of problem. Also for the purpose of solving relatively large sized problems in practice, we develop and test suitable heuristic procedures. For the NAP, we propose a quasi-dynamic assignment scheme which is based on the incremental assignment technique. This quasi-dynamic assignment method assumes that the current aircraft route is influenced only by the previous aircraft assigned to the network. This simplified assumption obviates the need for iterative rerouting procedures to reach a pure equilibrium state which might not be achievable in practical taxiway operations. To evaluate the overall system, we develop a microscopic simulation model. The simulation model is designed to have the capability for reproducing not only the dynamic behavior of aircraft, but also incorporates communication activities between controllers and pilots. These activities are critical in ATC operations, and in some instances, might limit the capacity of the facility. Finally, using the developed simulation model named Virginia Tech Airport Simulation Model (VTASM) in concert with ASP and NAP, we compare the overall efficiencies of several control strategies, including that of the existing control system as well as of the proposed advanced control system. / Ph. D.
248

Řízení adaptivního dopravního uzlu / Adaptive Traffic Junction Controller

Hudec, Karel January 2009 (has links)
This work will study intelligent systems for traffic control and will design an application which will control existing traffic junction. From formal specification to an implementation. It will be a real time application. That means it will work in real time. We will also study real time operating systems and we will choose the most suitable for our application and we will implement our application on this operating system.
249

An Avian Target Processing Algorithm to Mitigate Bird Strike Risk in Aviation

Milluzzi, Anthony J. 11 June 2019 (has links)
No description available.
250

Job demands, job resources, safety behaviours, and burnout in air traffic management

Kalaitzis, Eleni Anna January 2017 (has links)
A research report submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Arts (Organisational Psychology), 2017 / The aim of the present study was to utilise a mixed methods design as a means of investigating the relation between job demands, job resources, safety, and burnout in Air Traffic Management (ATM) technicians. It was also of interest to determine participants’ perspectives on the job demands and resources that may be present in their occupational environment, their participation in safety behaviours, and their perceptions regarding their work and safety performance. Non-probability, convenience sampling was employed to acquire the participants of the present research study. Participants included 33 ATM technicians (50.77% response rate) who took part in the quantitative component of the research study and 14 ATM who took part in the interview process. Participants’ ages ranged from 27 to 55 years (M = 38.91; SD = 8.76) and 90.1% were male (n = 30). Jackson and Rothmann’s (2005) original Job Demands-Resources Scale was used for the assessment of the job demands and resources sixteen items were also added to the original JDRS scale. Sixteen items were added to incorporate the possible job resources and demands experienced by ATM technicians, which were separated into the following sub-scales: shifts, weather conditions, travel, and equipment. Schaufeli, Leiter, Maslach, and Jackson’s (1996) Maslach Burnout Inventory-General Survey (MBIGS) was used to assess ATM technicians’ burnout. Safety behaviours were assessed through the integration of items found within two safety behaviour scales developed by Neal and Griffin (2006) and Hofmann and Morgeson (1999). A semi-structured interview process consisting of open-ended questions was used to discuss the following issues: job tasks, job demands, job resources, burnout, job safety, work-family spillover, and job performance. The findings depicted a weak, positive correlation between the perception of job demands and the experience of burnout (r = .376, p < .05) and a weak, negative correlation between the perception of job resources and the experience of burnout (r = -.383, p < .05). Job resources significantly predicted the experience of burnout (β = -.494, p = .002), as did job demands (β = .489, p = .003). A moderate, positive correlation between the perception of job resources and safety behaviours was obtained (r = .514, p < .01). The participants’ perceptions of job resources explained 26.5% of the variance in safety behaviours, (R2= .265, F(1, 31) = 11.16, p < 0.05. ATM technicians took part in the following safety behaviours: they consistently communicated with both management and air traffic controllers as a way of knowing exactly what the problem is before they went to a site, they took part in training programs as a means of keeping up to date with the latest technological knowledge, attended safety meetings, always communicated with management on how to increase safety, and made sure that a first aid kit was always available. ATM technician’s safety and performance appeared to be heavily influenced by their own personal understanding of the occupation’s risks, the weather conditions that take place on each specific site, the safety equipment that is worn, the knowledge of the possible repercussions that may arise from making any mistakes, and their own individual mood or disposition. / XL2018

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