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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.
231

’The Big Five of Teamwork’ i en flygtrafikledningsdomän : En observationsstudie på Arlanda ATCC / 'The Big Five of Teamwork' in an air traffic control domain : An observation study at Arlanda ATCC

Adolfsson, Sofie January 2018 (has links)
Idag är många branscher beroende av ett gediget teamwork. Det finns dock ett behov av objektiva mätsystem för teamwork och därför har detta projekt som syfte att skapa och testa ett observationsprotokoll utifrån den teoretiska modellen ’The Big Five of Teamwork’ framtagen av Salas, Sims & Burke (2005). Observationsprotokollet användes för att observera teamwork mellan två flygledare på Arlanda ATCC. Därefter fick flygledarna svara på en enkät för att bidra med subjektiva aspekter från modellen. Totalt genomfördes 15 stycken strukturerade observationer. Resultatet visade att det är möjligt att skatta teamwork på flygledare med hjälp av ett observationsprotokoll baserat på sex av åtta komponenter, där inte teamorientering och gemensam mental modell ingick. Komponenterna visade sig vara mer än bara ett observerbart beteende och enbart observationer frambringar inte en rättvis bild över komponenten. Resultatet visade också på att flygledarna själva upplever samtliga komponenter som en del av arbetet. Observationerna visade att samarbetet kunde se olika ut och skilja sig från team till team, och att flygledarna anpassar sig efter varandras behov. / Today, many industries are dependent on a solid teamwork. However, there is a need for objective measurement assessment for teamwork and therefore this project aims to create and test an observation protocol based on the theoretical model ’The Big Five of Teamwork’ compiled by Salas, Sims & Burke (2005). The observation protocol was used to observe teamwork between two air traffic controllers at Arlanda ATCC. After the observations the air traffic controllers answered a survey to receive subjective aspects from the model. A total of 15 structured observations were conducted. The results revealed that it’s possible to estimate teamwork on air traffic controllers using an observation protocol based on six of eight components, where team orientation and shared mental model were not included. The components appeared to be more than just an observable behavior, thus only observations does not give a fair picture of the component. The result also showed that air traffic controllers themselves perceive all components as a part of the work. The observations showed that the cooperation could look different and differ from team to team, and that air traffic controllers adapt to each other’s needs.
232

Occupational stress and coping resources in air traffic control

Tshabalala, Matita Petrus 11 1900 (has links)
The aim of this study was to investigate how air traffic controllers cope with stress and also to determine whether there were statistically significant differences in the coping behaviour of air traffic control staff from different groups. The study was conducted on a sample of Air Traffic Controllers who control civilian aircraft in the South African airspace. The coping resources inventory (CRI) assessment was used to collect data and analysed to determine how controllers cope with stress and whether there are differences in the coping behaviour of air traffic control staff from different groups. The results showed that air traffic controllers use emotional coping resources to cope with stressful work situations and make less use of cognitive coping resources. The results also showed that there were no statistically significant differences in the coping behaviour of air traffic control staff from different groups. / Industrial and organisational psychology / M.A. (Industrial and Organisational Psychology)
233

Improved operational efficiency as a measure for alleviating port congestion at the Cape Town container terminal

Powles, Michael John January 2004 (has links)
Thesis (MTech (Business Administration))--Cape Technikon, 2004. / The Cape Town Container Terminal (CTCT) facilitates the handling process ofImport and Export containers for the Western Cape and other regions. South African Port Operations (SAPO), a division of the transport parastatal Transnet, is the operator that handles container volumes through the terminal. Due to the nature of its operations, it focuses on service standards within the industry. The International Shipping Industry expects this container terminal to conform by providing the same operational standards and service they receive from other international ports. Container terminal efficiency and productivity were not providing a reliable and efficient service for vessels calling to CTCT. Delays became so endemic that the shipping lines instituted a seventy-five dollar congestion surcharge on each container being handled This surcharge was passed on to the consumer therefore increasing the logistical cost of goods and services. The fact that a shipping line was bypassing Cape Town altogether was an indication that the Terminal was experiencing difficulty in maintaining its port status as a prominent and efficient container terminal at the southern tip of Africa.
234

Rigid barrier or not? : Machine Learning for classifying Traffic Control Plans using geographical data

Wallander, Cornelia January 2018 (has links)
In this thesis, four different Machine Learning models and algorithms have been evaluated in the work of classifying Traffic Control Plans in the City of Helsingborg. Before a roadwork can start, a Traffic Control Plan must be created and submitted to the Traffic unit in the city. The plan consists of information regarding the roadwork and how the work can be performed in a safe manner, concerning both road workers and car drivers, pedestrians and cyclists that pass by. In order to know what safety barriers are needed both the Swedish Association of Local Authorities and Regions (SALAR) and the Swedish Transport Administration (STA) have made a classification of roads to guide contractors and traffic technicians what safety barriers are suitable to provide a safe workplace. The road classifications are built upon two rules; the amount of traffic and the speed limit of the road. Thus real-world problems have shown that these classifications are not applicable to every single case. Therefore, each roadwork must be judged and evaluated from its specific attributes. By creating and training a Machine Learning model that is able to determine if a rigid safety barrier is needed or not a classification can be made based on historical data. In this thesis, the performance of several Machine Learning models and datasets are presented when Traffic Control Plans are classified. The algorithms used for the classification task were Random Forest, AdaBoost, K-Nearest Neighbour and Artificial Neural Network. In order to know what attributes to include in the dataset, participant observations in combination with interviews were held with a traffic technician at the City of Helsingborg. The datasets used for training the algorithms were primarily based on geographical data but information regarding the roadwork and period of time were also included in the dataset. The results of this study indicated that it was preferred to include road attribute information in the dataset. It was also discovered that the classification accuracy was higher if the attribute values of the geographical data were continuous instead of categorical. In the results it was revealed that the AdaBoost algorithm had the highest performance, even though the difference in performance was not that big compared to the other algorithms.
235

Um modelo matemático para otimizar o descarregamento de navios num terminal graneleiro / A mathematical model to optimize the unloading of ships in a grain terminal

Cereser, Bruno Luís Hönigmann, 1988- 23 August 2018 (has links)
Orientadores: Luiz Leduino de Salles Neto, Antonio Carlos Moretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-23T22:02:01Z (GMT). No. of bitstreams: 1 Cereser_BrunoLuisHonigmann_M.pdf: 8696662 bytes, checksum: b4ca681ecf08f10afa47d00b3a879e9e (MD5) Previous issue date: 2013 / Resumo: O transporte marítimo é fundamental para grandes empresas de caráter global. Em 2009 80% do comércio mundial foi realizado via transporte marítimo e desde então esse número só tem crescido. Devido a esse alto fluxo nos portos mundiais, surgiu o problema de alocação de navios em berços, que tem por finalidade estabelecer uma sequência de atendimento de navios para cada berço disponível no cais, visando minimizar o tempo total da operação e espera dos navios dentro dos portos. Nesse trabalho o problema de alocação de navios em berços será abordado considerando berços dependentes, e também a divisão das máquinas portuárias em berços consecutivos aplicados a terminais do Porto de Tubarão (ES). Para a representação matemática dos processos desses terminais do porto de tubarão foram desenvolvidos novos modelos matemáticos. Os testes computacionais foram exitosos / Abstract: The maritime transportation is essential to global companies. In 2009 80% of global trade was made by maritime transportation, and over the year this number has raised. Because of this high flux, the BAP (Berth Allocation Problem) arose. The BAP have intent to discovery the vessel allocation sequence in every berth with the minimum total wait time. In this work, the berths of BAP will be considered dependents, we also considered the division of portuary machines between consecutive berths. The objective of this work is the mathematical representation of the terminals Produtos Diversos and Praia Mole of the Tubarão port. For this reasons we propose here unprecedented mathematical models / Mestrado / Matematica Aplicada / Mestre em Matemática Aplicada
236

Norme(s) et usage(s) langagiers : le cas des communications pilote-contrôleur en anglais / Linguistic norm(s) and use : a case study of pilot-controller communications

Lopez, Stéphanie 20 September 2013 (has links)
Dans cette thèse, nous menons une réflexion sur les notions de norme(s) et d’usage(s) langagiers dans le cadre du domaine du contrôle aérien. Ce domaine offre l’exemple parfait de la mise en œuvre d’une norme langagière : la "phraséologie" aéronautique, le langage opératif censé permettre des communications sûres et efficaces entre pilotes et contrôleurs, lors des situations les plus courantes. Lorsque la phraséologie ne suffit pas, ces derniers ont recours à une forme langagière plus naturelle, le "plain language". De nombreux problèmes relatifs à la mise en œuvre de ce dernier ont rapidement vu le jour et ont suscité des interrogations, notamment chez les professionnels de l’enseignement de l’anglais de l’aviation. Pour répondre aux besoins spécifiques de l’ENAC, cette thèse dresse un panorama des usages faits de la langue anglaise par les contrôleurs français et les pilotes étrangers lors de leurs communications radiotéléphoniques. Notre méthode d’analyse consiste en une étude comparative entre un corpus de référence, représentant la norme, et un corpus de communications réelles, représentant les usages. Cette analyse comparative nous permet de repérer, de décrire et de catégoriser les formes langagières employées lors de situations routinières de la navigation aérienne. Certaines différences sont ainsi repérées entre les deux corpus. En fonction de la situation, les pilotes et les contrôleurs peuvent procéder à des variations d’ordre lexical, sémantique, syntaxique et discursif. Alors que certains semblent subir l’influence de la langue naturelle, d’autres semblent mettre en œuvre une stratégie communicationnelle pour tenter d’"humaniser" ou de modaliser le contenu de leurs messages. / This thesis is a reflection upon the notions of linguistic norm(s) and usage(s) within the domain of Air Traffic Control. This domain provides a prime example of an established linguistic norm: that of “phraseology”, the controlled language used between pilots and controllers to optimise and secure their most frequent communications. If pilots and controllers do not speak the same language, the phraseology used is then based on English. Whenever the limits of phraseology are reached, pilots and controllers revert to a more natural form of language which has only recently been described in this domain: plain language. However, several problems relating to the implementation of plain language and phraseology have been identified by professional Aviation English teachers. To meet the needs of the French civil aviation university (ENAC), a survey of the different uses of the English language by French controllers and international pilots is presented. The method of analysis consists in a comparative study between two corpora: one representing the prescribed norm and the other corresponding to real pilot-controller communications. This comparative analysis allows the description and categorization of the different types of languages used on the frequency in air navigation typical situations. Some differences are found between the two corpora. Depending on the situation, pilots and controllers’ messages can indeed vary from a lexical, semantic or syntactic and discursive point of view. Some variations reflect the influence of natural language on the speakers while others can be considered as a strategy to “humanise” radiotelephony communications.
237

Neue Ansätze zur Nutzung von Induktionsschleifen-Daten an Lichtsignalanlagen

Tischler, Kathleen 11 April 2016 (has links) (PDF)
Die vorliegende Dissertationsschrift widmet sich zwei Zielen: Mittels Induktionsschleifen-Detektoren einerseits die Verkehrsregelung an Knotenpunkten durch die Minimierung von Fahrzeughalten zu verbessern, und andererseits eine Veränderung der Verkehrsqualität durch die Schätzung von Kfz-Wartezeiten automatisiert zu erheben. Im ersten Teil wird ein modellbasiertes Steuerverfahren entwickelt, das Grünzeiten verkehrsabhängig und lokal anpasst. Es kann sehr gut in eine übergeordnete Steuerung zur Koordinierung in Verkehrsnetzen eingebunden werden und überlässt dieser die Optimierung von Phasenfolgen, Umlauf- und Versatzzeiten. Um auch bei hohen Auslastungen Kapazitäten bestmöglich zu nutzen, priorisiert es zunächst die Leerung von Warteschlangen. Anschließend erfolgt die Anpassung der Grünzeiten zwischen einer minimalen und maximalen Dauer so, dass Fahrzeughalte minimiert werden. Dafür werden Detektoren in ausreichender Entfernung im Zufluss einer Kreuzung verwendet, um Fahrzeugankünfte an der Haltelinie für die aktuelle und die nächste Phase zu prognostizieren. Bei der sich anschließenden Bilanzierung potenzieller Fahrzeughalte und der Wahl des günstigsten Umschaltzeitpunktes kann auf zusätzliche Modellannahmen verzichtet werden. Die Simulationsergebnisse zeigen, dass bei einer Minimierung der Fahrzeughalte gleichzeitig eine Reduktion von Wartezeiten möglich ist. Im zweiten Teil werden Kfz-Wartezeiten auf Basis der meist bereits vorhandenen Induktionsschleifen-Detektoren im Zufluss und im Abfluss einer Kreuzung geschätzt. Dafür werden die Zeitpunkte der Fahrzeugüberfahrten an einem Zufluss- und einem Abflussquerschnitt getrennt gemessen werden. Aus ihnen wird jeweils ein mittlerer Überfahrzeitpunkt ermittelt und nach Berücksichtigung der freien Fahrzeit eine mittlere Wartezeit geschätzt. Messintervalle an beiden Querschnitten, die um die mittlere freie Fahrzeit versetzt sind, sowie eine unbedingte Warteschlangenleerung am Ende einer Messung sollen sicherstellen, dass potenziell dieselben Fahrzeuge erfasst werden. Auf eine Fahrzeugwiedererkennung und damit auf eine Ausrüstung mit zusätzlicher Technik kann dadurch verzichtet werden. Damit sich das Verfahren für den Praxiseinsatz eignet, muss es möglichst robust gegenüber zufälligen Detektorfehlern sein. Dafür wird ein Fehlermodell entwickelt und mögliche Abweichungen gegenüber einer korrekten Messung untersucht. Aufgrund der unabhängigen Berechnung von mittleren Überfahrzeiten aus der getrennten Messung im Zufluss und im Abfluss zeigt sich, dass zufällige Fehler nicht zu systematischen Abweichungen in der Wartezeitschätzung führen.
238

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.
239

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.
240

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.

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