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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.
1

TRAJECTORY PATTERN IDENTIFICATION AND CLASSIFICATION FOR ARRIVALS IN VECTORED AIRSPACE

Chuhao Deng (11184909) 26 July 2021 (has links)
<div> <div> <div> <p>As the demand and complexity of air traffic increase, it becomes crucial to maintain the safety and efficiency of the operations in airspaces, which, however, could lead to an increased workload for Air Traffic Controllers (ATCs) and delays in their decision-making processes. Although terminal airspaces are highly structured with the flight procedures such as standard terminal arrival routes and standard instrument departures, the aircraft are frequently instructed to deviate from such procedures by ATCs to accommodate given traffic situations, e.g., maintaining the separation from neighboring aircraft or taking shortcuts to meet scheduling requirements. Such deviation, called vectoring, could even increase the delays and workload of ATCs. This thesis focuses on developing a framework for trajectory pattern identification and classification that can provide ATCs, in vectored airspace, with real-time information of which possible vectoring pattern a new incoming aircraft could take so that such delays and workload could be reduced. This thesis consists of two parts, trajectory pattern identification and trajectory pattern classification. </p> <p>In the first part, a framework for trajectory pattern identification is proposed based on agglomerative hierarchical clustering, with dynamic time warping and squared Euclidean distance as the dissimilarity measure between trajectories. Binary trees with fixes that are provided in the aeronautical information publication data are proposed in order to catego- rize the trajectory patterns. In the second part, multiple recurrent neural network based binary classification models are trained and utilized at the nodes of the binary trees to compute the possible fixes an incoming aircraft could take. The trajectory pattern identifi- cation framework and the classification models are illustrated with the automatic dependent surveillance-broadcast data that were recorded between January and December 2019 in In- cheon international airport, South Korea . </p> </div> </div> </div>
2

Increasing the resilience of air traffic networks using a network graph theory approach

Dunn, Sarah, Wilkinson, Sean M. 18 November 2020 (has links)
Air traffic networks are essential to today’s global society. They are the fastest means of transporting physical goods and people and are a major contributor to the globalisation of the world’s economy. This increasing reliance requires these networks to have high resilience; however, previous events show that they can be susceptible to natural hazards. We assess two strategies to improve the resilience of air traffic networks and show an adaptive reconfiguration strategy is superior to a permanent re-routing solution. We find that, if traffic networks have fixed air routes, the geographical location of airports leaves them vulnerable to spatial hazard.
3

Intégration des villes d'Europe centrale et orientale dans l'économie-monde depuis 1989 : une entrée par les réseaux internationaux de commerce, de transport aérien et de firmes / Integration of Central and Eastern European cities into the world-economy since 1989 : in the light of trade, air traffic and firm networks

Zdanowska, Natalia 31 October 2018 (has links)
Plus d’un quart de siècle après la chute du Mur de Berlin, la radicalité des changements politiques et économiques, caractérisés par l’intégration dans l’économie-monde et l’Union européenne, ainsi que par la récente montée du nationalisme, continue à poser des questions quant au devenir de l’espace centre-est européen. Ce contexte amène à appréhender dans ce travail l’effet de ces bouleversements au prisme des villes et de leurs évolutions. Trois forces majeures ayant guidé les transformations en Europe centrale et orientale sont examinées depuis 1989 : l’européanisation, la mondialisation et le changement endogène – relevant des traces du passé. Les dynamiques respectives de ces trois forces sont évaluées au moyen d’une approche interurbaine. Les échanges économiques entre villes centre-est européennes et celles du reste du monde sont examinés au travers de réseaux transnationaux et mondialisés – de transport aérien et de firmes. Ces échanges sont confrontés aux réseaux commerciaux entre pays. Cette thèse contribue à montrer que l’intégration à l’économie-monde s’est accompagnée d’un renforcement des logiques de polarisation divisant l’espace centre-est européen entre le Nord-Ouest et le Sud-Est. Cette intégration en cours, ou plutôt ces différentes « intégrations », ne se sont toutefois pas opérées uniquement au profit des métropoles. En effet, malgré une prédominance de l’européanisation, les liens de l’époque communiste constituent une force économique majeure pour certaines petites et moyennes villes – à l’image de l’entre-deux historique de l’espace centre-est européen. / A quarter of century after the fall of the Berlin Wall, radical political and economic changes, integration into the world economy and the European Union, and the recent reinforcement of nationalism are still persistent subjects of debate with regards to the future of Central and Eastern Europe. This thesis examines three major transformative forces in Central and Eastern Europe since 1989 at city-level: europeanisation, globalization and endogenous changes – related to path dependence effects. The dynamics of these three forces are analyzed by looking at the evolution of economic exchanges of CEE cities with other worldwide cities in the context of transnational and globalized networks – air traffic and firms. They are confronted with trade networks at country level. This dissertation illustrates that integration into the world-economy has deepened polarization in Central and Eastern Europe between the Nord-West and the South-West. This integration process or different types of integration are not only a matter for big cities and metropolises. In spite of the predominance of europeanisation, links from the communist period continue to be a major economic force, especially for small and medium-sized cities, reflecting the historical in-between situation of Central and Eastern Europe. / Ćwierć wieku później, radykalne zmiany polityczne i gospodarcze po upadku Muru Berlińskiego, integracja z gospodarką światową, przystąpienie do Unii Europejskiej oraz nasilające się tendencje nacjonalistyczne są wciąż bieżącymi tematami w dyskusji o przyszłości Europy Środkowo-Wschodniej. W tym kontekście, dysertacja proponuje analizę zmian systemowych, które dokonały się w regionie na poziomie miast. Przedmiotem badania są trzy procesy towarzyszące transformacjom po 1989: europeizacja, globalizacja oraz przemiany w regionie uwarunkowane relacjami z przeszłości. Dynamika wymienionych trzech procesów zostanie zbadana w odniesieniu do wymian ekonomicznych między miastami Europy Środkowo-Wschodniej a innymi miastami Europy i świata w sferze międzynarodowych powiązań lotniczych i firmowych, porównanych z siecią handlową ukształtowaną między państwami regionu. Wnioski badawcze wykazują, że w rezultacie integracji z gospodarką światową pogłębia się polaryzacja przestrzeni Europy Środkowo-Wschodniej w układzie północny zachód i południowy wschód. Różnorodność typów integracji odnosi się nie tylko do metropolii i dużych miast. Wobec dominującej siły europeizacji, powiązania z miastami z czasów komunistycznych są nadal ważnym aspektem funkcjonowania miast małych i średnich, ilustrując zarazem historyczną sytuację entre-deux Europy Środkowo-Wschodniej.

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