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Ubåtsjaktförmågans utveckling på sjöoperativ helikopter : En studie av bakomliggande drivkrafterWallenburg, Paula January 2013 (has links)
The aim of the present study is to explain what where the driving forces behind the development of antisubmarine warfare skill on Swedish sea operational helicopters during the time 1980-92. The study is done by using two different perspective, based on Graham Allison scientific explanation models found in his book Essence of Decision. In the study the perspectives are named “rational actor” and “governmental politics”. The purpose is to investigate if respective model can explain the development of antisubmarine warfare skill on Swedish helicopters during the previously mentioned timeframe. The result of the study is that by using the rational actor perspective the development of anti submarine warfare can be explained in a large extent. The study proves that there were a well-defined threat and that consensus was that this threat would be met i.e. with anti submarine warfare resources. It cannot be demonstrated that the helicopter and the development of its anti submarine warfare capability was the single most suitable option. By using the model governmental politics, the development is not significantly explained because no internal differences of large extent have been demonstrated. The model contributes rather to illuminate the actors and factors that shaped their actions. If the models are used as complement to each other a wider perspective of what has happened is shown, but the explanation is not strengthened. / Syftet med uppsatsen är att studera de drivkrafter som låg bakom utvecklingen av den svenska ubåtsjaktförmågan på sjöoperativ helikopter under tidsperioden 1980-92. Studien genomförs med hjälp av två perspektiv vilka är baserade på Graham Allisons samhällsvetenskapliga modeller, och dennes bok Essence of Decision. I arbetet benämns perspektiven rationell aktörsmodell respektive maktspelsmodell. Ambitionen är att undersöka om respektive modell kan förklara utvecklingen av ubåtsjaktförmågan på sjöoperativ helikopter under nämnda period. Resultatet av studien är att med hjälp av den rationella aktörsmodellen kan bakomliggande drivkrafter till utvecklingen av ubåtsjaktförmågan i stor utsträckning påvisas. Studien påvisar att det fanns ett väl definierat hot samt att enighet rådde att detta hot skulle bemötas, d.v.s. med ubåtsjaktresurser. Dock kan inte påvisas att helikopter och utvecklingen av dess ubåtsjaktförmåga var det enskilt lämpligaste alternativet. Med hjälp av maktspelsmodellen kan orsakerna till utvecklingen inte nämnvärt förklaras eftersom inget maktspel av större omfattning har påvisats. Den senare modellen bidrar snarare till att belysa aktörer och faktorer som formade deras agerande. Nyttjar man modellerna som komplement till varandra ges en bredare bild av skeendet men förklaringen av bakomliggande faktorer stärks inte.
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Magnetic signature characterization of a fixed-wing vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV)Hansen, Cody Robert Daniel 17 December 2018 (has links)
The use of magnetometers combined with unmanned aerial vehicles (UAVs) is an emerging market for commercial and military applications. This study presents the methodology used to magnetically characterize a novel fixed-wing vertical take-off and landing (VTOL) UAV. The most challenging aspect of integrating magnetometers on manned or unmanned aircraft is minimizing the amount of magnetic noise generated by the aircraft’s onboard components. As magnetometer technology has improved in recent years magnetometer payloads have decreased in size. As a result, there has been an increase in opportunities to employ small to medium UAV with magnetometer applications. However, in comparison to manned aviation, small UAVs have smaller distance scales between sources of interference and sensors. Therefore, more robust magnetic characterization techniques are required specifically for UAVs. This characterization determined the most suitable position for the magnetometer payload by evaluating the aircraft’s static-field magnetic signature. For each aircraft component, the permanent and induced magnetic dipole moment characteristics were determined experimentally. These dipole characteristics were used to build three dimensional magnetic models of the aircraft. By assembling the dipoles in 3D space, analytical and numerical static-field solutions were obtained using MATLAB computational and COMSOL finite element analysis frameworks. Finally, Tolles and Lawson aeromagnetic compensation coefficients were computed and compared to evaluate the maneuver noise for various payload locations. The magnetic models were used to study the sensitivity of the aircraft configuration and to simultaneously predict the effects at potential sensor locations. The study concluded by predicting that a wingtip location was the area of lowest magnetic interference. / Graduate
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