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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.
31

Making Place for Space : a History of 'Space Town' Kiruna 1943-2000

Backman, Fredrick January 2015 (has links)
Science and technology have a tendency to clump together in places where they spawn other forms of societal activities. Sometimes these places become famous through processes known as place-making, or the social construction of place. Because the scientific and technological activities affect the places, and the places conversely affect the science and technology, it is relevant to study how and why these connections emerge. This dissertation examines the particular case of the northern Swedish town of Kiruna, which has become known for being a `space town' because of its scientific, technological, and other activities that relate to the near space around the earth. The overall objective is to analyse the processes underlying the making of Kiruna as a space town in the period 1943--2000. Five parts make up the study. First is an examination of how the development of space physics research in Kiruna led to the setting up of a scientific observatory. The second part studies how the Swedish participation in the European Space Research Organisationmade Kiruna the place for a rocket base. Next follows an analysis of how local business efforts contributed to forming a new satellite technology business and the Space House office building. The fourth part concerns how the visions to establish a space `university' eventually led to the emergence of the Space Campus. Last is an epilogue that briefly analyses the space tourism efforts in Kiruna. A central finding is that the space town has emerged as the result of entwined processes where, on the one hand, ideas about the near space around the earth have led to new activities and physical structures, and, on the other hand, these new activities and built structures conversely have inspired to new ideas. Of importance is also the geographical place where these developments have occurred. Here, a reoccurring argument to placing the activities and structures in Kiruna was the town's geographically favourable location for specific scientific and technological activities. Another finding is that the development has gradually led to the emergence of a kind of identity or notion of Kiruna as a particular place for space activities. Although this form of place-making has occurred largely through spontaneous processes, it was also the result of intentional efforts. Together, these different place-making processes have formed the `space town' of Kiruna.
32

Utilizando as ci?ncias espaciais e a astron?utica na constru??o de atividades pr?ticas em ensino de f?sica

Machado, Jo?o Felisardo 19 May 2006 (has links)
Made available in DSpace on 2014-12-17T15:05:06Z (GMT). No. of bitstreams: 1 JoaoFelisardoM.pdf: 1390724 bytes, checksum: 3c669bea60181234ba1aa8160bc9bb5d (MD5) Previous issue date: 2006-05-19 / In this work we consider the use of new technologies fron the Space Science and Astronautical, in the learning process, incorporating technical and conceptions of physics Spatial what can take on the response of some problems what there are a lot insistent in populate the mind of professors and followers regarding agreement of these conceptions into the level Average. Intending to bring another contribution to Physics teaching practice, especially Classical Mechanics, but introducing many introductory concepts from Modern Physics, since this topic is considered of great interest for teachers and students, for it involves high technology. It s advanced manufacturing demand certain processes that make possible the application of those concepts / Neste trabalho refletimos sobre a utiliza??o das novas tecnologias provenientes das pesquisas das Ci?ncias Espaciais e da Astron?utica no processo educativo, incorporando t?cnicas e conceitos da F?sica Espacial que podem levar ? resposta de alguns problemas que h? muito insistem em povoar a mente de professores e alunos quanto ao entendimento desses conceitos no n?vel M?dio. Com ele pretendemos levar mais uma contribui??o ? pr?tica de ensino nas aulas de F?sica, especialmente da Mec?nica Cl?ssica, permeando-se, por?m, v?rios conceitos introdut?rios da F?sica Moderna, haja vista que o tema gerador ? instigante, de grande interesse por parte de mestres e aprendizes, envolvendo tecnologia de ponta, cujos componentes de fabrica??o passam por processos que possibilitam a contextualiza??o desses conceitos
33

Structuration ontologique et étude sémantico-syntaxique de la terminologie des sciences et techniques spatiales (arabe - français - anglais) / Ontological structuration and semantico-syntactic studies of the terminology related to the space science and technology (Arabic - French - English )

Alshtaiwi, Ma'moun 17 June 2016 (has links)
La terminologie des sciences et techniques spatiales (STS) relevée sur corpus est étudiée dans le cadre et avec la structuration ontologique du domaine. La formation morphosyntaxique, le caractère de l’unité terminologique ainsi que le schéma d’arguments (expressions prédicatives et arguments) sont analysés tant en contexte qu’indépendamment du contexte. L’unité terminologique se caractérise par un degré de figement relatif : une des propriétés de l’unité terminologique « longue » est que celle-ci peut souvent être décomposée, elle peut avoir un comportement discursif, notamment la reprise anaphorique et la réduction par suppression de l’un de ses composants. Dans ce dernier cas, il s’agit de certains aspects de la terminologisation tels que la chute d’une information non différentielle et le maintien d’un élément nominal ou caractérisant. Ainsi, plusieurs aspects sont des facteurs constants qui peuvent permettre de mettre en évidence l’évolution diachronique de l’unité terminologique. L’apport de la structuration ontologique est analysé dans le but de décrire non seulement les concepts des STS mais aussi l’emploi du schéma d’arguments (verbal et nominal) dans le corpus en se fondant sur des étiquettes sémantico-syntaxiques. Une analyse du verbe spécialisé a été développée pour fournir des informations utiles à la constitution des bases de données terminologiques multilingues ou encore la rédaction des définitions technoscientifiques. L’étude a permis également de décrire des verbes absents dans les dictionnaires de spécialité, de montrer comment un verbe peut acquérir un nouveau sens spécialisé et d’identifier l’agent typique de ces verbes. Deux classifications du verbe spécialisé selon ses emplois et sa structure morphosyntaxique ont été proposées : unité verbale simple (UVS) et unité verbale complexe (UVC). Un syntagme implique l’une des deux analyses : unité compositionnelle ou unité non-compositionnelle. Selon la situation contextuelle, la définition du verbe en langue de spécialité a permis enfin de distinguer les trois acceptions du verbe : verbe très spécialisé, verbe polysémique et verbe support. / The terminology related to the space science and technology (SST), corpus-based approach, is studied within the framework of the ontological structure pattern. The morpho-syntactical formation of the terminological unit, its characteristics as well as the schemata of arguments (predicative expressions and arguments) are both analyzed within the context and beyond the context. It’s characterized by a level of relative fixed structure: one of the properties of the “long” terminological unit that can often be decomposed. It can have a discursive behavior in particular, discourse anaphora, and the reduction by deletion of one of its components. In the latter case, this refers to certain aspects of the terminologization such as non-differential element falling and a characteristic or nominal element maintaining. Therefore, some aspects are constant factors which allow to highlight the diachronic evolution of the terminological unit. The outcome of the ontological structure is analyzed with the aim of describing not only the concepts of the SST, but also the use of the schemata of arguments i.e. verbal and nominal in the corpus by establishing itself on the semantic-syntactical labels. An analysis of the specialized verb was developed to supply useful information for the constitution of the multilingual terminological database or to give techno-scientific definitions. The study also allowed to describe absent verbs in the specialized dictionaries, to show how a verb can acquire a new specialized meaning, to identify the typical agent of the specialized verbs. There are two classifications of the specialized verb according to their uses and their morpho-syntactical structure were proposed as; simple verbal unit (SVU) and complex verbal unit (CVU). A syntagm involves one of the two analyzes: compositional unit or non-compositional unit. According to the situational context, the definition of the verb in LSP allowed finally to identify three meanings of the verb: very specialized verb, polysemous verb, and support verb.
34

Novel Analysis Framework Using Quantum Optomechanical Readouts For Direct Detection Of Dark Matter

Ashwin Nagarajan (10702782) 06 May 2021 (has links)
With the increase in speculation about the nature of our universe, there has been a growing need to find the truth about Dark Matter. Recent research shows that the Planck-Mass range could be a well-motivated space to probe for the detection of Dark Matter through gravitational coupling. This thesis dives into the possibility of doing the same in two parts. The first part lays out the analysis framework that would sense such an interaction, while the second part outlines a prototype experiment that when scaled up using quantum optomechanical sensors would serve as the skeleton to perform the analysis with.
35

QUALITY ASSESSMENT OF GEDI ELEVATION DATA

Wildan Firdaus (12216200) 13 December 2023 (has links)
<p dir="ltr">As a new spaceborne laser remote sensing system, the Global Ecosystem Dynamics Investigation, or GEDI, is being widely used for monitoring forest ecosystems. However, its measurements are subject to uncertainties that will affect the calculation of ground elevation and vegetation height. This research intends to investigate the quality of the GEDI elevation data and its relevance to topography and land cover.</p><p dir="ltr">In this study, the elevation of the GEDI data is compared to 3DEP DEM, which has a higher resolution and accuracy. All the experiments in this study are conducted for two locations with vastly different terrain and land cover conditions, namely Tippecanoe County in Indiana and Mendocino County in California. Through this investigation we expect to gain a comprehensive understanding of GEDI’s elevation quality in various terrain and land cover conditions.</p><p dir="ltr">The results show that GEDI data in Tippecanoe County has better elevation accuracy than the GEDI data in Mendocino County. GEDI in Tippecanoe County is almost four times more accurate than in Mendocino County. Regarding land cover, GEDI have better accuracy in low vegetation areas than in forest areas. The ratio can be around three times better in Tippecanoe County and around one and half times better in Mendocino County. In terms of slope, GEDI data shows a clear positive correlation between RMSE and slope. The trend indicates as slope increases, the RMSE increases concurrently. In other words, slope and GEDI elevation accuracy are inversely related. In the experiment involving slope and land cover, the results show that slope is the most influential factor to GEDI elevation accuracy.</p><p dir="ltr">This study informs GEDI users of the factors they must consider for forest biomass calculation and topographic mapping applications. When high terrain slope and/or high vegetation is present, the GEDI data should be checked with other data sources like 3DEP DEM or any ground truth measurements to assure its quality. We expect these findings can help worldwide users understand that the quality of GEDI data is variable and dependent on terrain relief and land cover.</p>
36

Spacecraft dynamic analysis and correlation with test results : Shock environment analysis of LISA Pathfinder at VESTA test bed

Kunicka, Beata Iwona January 2017 (has links)
The particular study case in this thesis is the shock test performed on the LISA Pathfinder satellite conducted in a laboratory environment on a dedicated test bed: Vega Shock Test Apparatus (VESTA). This test is considered fully representative to study shock levels produced by fairing jettisoning event at Vega Launcher Vehicle, which induces high shock loads towards the satellite. In the frame of this thesis, some transient response analyses have been conducted in MSC Nastran, and a shock simulation tool for the VESTA test configuration has been developed. The simulation tool is based on Nastran Direct Transient Response Analysis solver (SOL 109), and is representative of the upper composite of Vega with the LISA Pathfinder coupled to it. Post-processing routines of transient response signals were conducted in Dynaworks which served to calculate Shock Response Spectra (SRS). The simulation tool is a model of forcing function parameters for transient analysis which adequately correlates with the shock real test data, in order to understand how the effect of shock generated by the launcher is seen in the satellite and its sub-systems. Since available computation resources are limited the parameters for analysis were optimised for computation time, file size, memory capacity,  and model complexity. The forcing function represents a release of the HSS clamp band which is responsible for fairing jettisoning, thus the parameters which were studied are mostly concerning the modelling of this event. Among many investigated, those which visibly improved SRS correlation are radial forcing function shape, implementation of axial impulse, clamp band loading geometry and refined loading scheme. Integration time step duration and analysis duration were also studied and found to improve correlation.  From each analysis, the qualifying shock environment was then derived by linear scaling in proportion of the applied preload, and considering a qualification margin of 3dB. Consecutive tracking of structural responses along shock propagation path exposed gradual changes in responses pattern and revealed an important property that a breathing mode (n = 0) at the base of a conical Adapter translates into an axial input to the spacecraft. The parametrisation itself was based on responses registered at interfaces located in near-field (where the clamp band is located and forcing function is applied) and medium-field with respect to the shock event location. Following shock propagation path, the final step was the analysis of shock responses inside the satellite located in a far-field region, which still revealed a very good correlation of results. Thus, it can be said that parametrisation process was adequate, and the developed shock simulation tool can be qualified. However, due to the nature of shock, the tool cannot fully replace VESTA laboratory test, but can support shock assessment process and preparation to such test. In the last part of the thesis, the implementation of some finite element model improvements is investigated. Majority of the panels in spacecraft interior exhibited shock over-prediction due to finite element model limitation. Equipment units modelled as lump masses rigidly attached with RBE2 elements to the panel surface are a source of such local over-predictions. Thus, some of the units were remodelled and transient responses were reinvestigated. It was found that remodelling with either solid elements, or lump mass connected to RBE3 element and reinforced by RBE2 element, can significantly improve local transient responses. This conclusion is in line with conclusions found in ECSS Shock Handbook.

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