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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.
71

Konjunkturförändringar och skolresultat : En kvantitativ studie om konjunkturens korrelation med skola och hemförhållanden och dess samband med skolresultat i årskurs 9

Viktoria Honkakumpu Gångfeldt, Niina-Maria, Walleborn, Oskar January 2023 (has links)
För att få bra valmöjligheter inom skola och utbildning krävs det att elever uppnår höga betyg. Tidigare forskning visar många olika resultat på faktorer som kan samvariera med elevens betyg, både positivt och negativt. De teoretiska mekanismer som tas upp i denna studie är Vygotskij som menar att vuxna är viktiga för barns lärande och Mead som har fokus på social interaktion där individer behöver ett samspel. En nedgång i konjunkturen kan påverka lärartätheten, det vill säga antal vuxna som finns tillgängliga i barnens vardag. Studien söker därför att undersöka om det går att finna korrelation mellan konjunkturen och skolresultat. För att besvara denna frågeställning har data samlats in ifrån Konjunkturinstitutet, Skolverket och Stockholmsenkäten. Korrelationen undersöks för skolelever i årskurs nio. Data behandlas genom regressioner och Spearmans korrelationstest för att undersöka om konjunkturen korrelerar med meritvärde eller om de ofta sammanfaller med varandra. Studien har inte funnit samband på en nationell nivå men i Stockholm finns en svag korrelation mellan meritvärde och konjunkturen. Studien har även testat för andra faktorer som elevens kön, lärartäthet, föräldrars utbildning och föräldrars sysselsättning, som alla korrelerar kraftigare med meritvärdet. Den nya aspekt denna studie lyfter fram är om skolresultat i Sverige i förhållande till konjunkturen korrelerar samt en uppdelning mellan nationell data och Stockholms data.
72

Observing Drought-Induced Crustal Loading Deformation Around Lake Mead Region via GNSS and InSAR: A Comparison With Elastic Loading Models

Zehsaz, Sonia 22 September 2023 (has links)
Lake Mead, the largest reservoir in the United States along the Colorado River on the border between the states of Nevada and Arizona, is one of the nation's most important sources of freshwater. As reported by the U.S. drought monitor (USDM), the entire region has been experiencing recurring severe to extreme droughts since the early 2000s, which have further intensified during the past two years. The drought-driven water deficit caused Lake Mead's water volume to decrease to approximately one-third of its capacity, creating a water crisis and negatively affecting soil and groundwater storage across the region. Water deficits have further reduced the mass of water loading on the Earth's crust, causing it to elastically deform. I observe this process from the ground by recording the vertical land motion occurring at Global Navigation Satellite System (GNSS) stations, or from space via Interferometric Synthetic Aperture Radar (InSAR) technology. In this study, I analyze vertical deformation observations from GNSS sites and multi-temporal InSAR analysis of Sentinel-1A/B to investigate the contribution of water mass changes in lake, soil, and groundwater to the deformation signal. To achieve this, I remove the effects of glacial isostatic adjustment and non-tidal mass loads from GNSS/InSAR observations. Our findings indicate that recent drought periods led to a notable uplift near Lake Mead, averaging 7.3 mm/year from 2012 to 2015 and an even larger rate of 8.6 mm/year from 2020 to 2023. Further, I provide an estimate of the expected vertical crustal deformation in response to well-known changes in lake and soil moisture storage. For that, I quantify hydrological loads through two different loading models. These include the application of Green's functions for an elastic, layered, self-gravitating, spherical Earth, and the Love load numbers from the Preliminary Reference Earth Models (PREMs), as well as elastic linearly homogeneous half-space Earth models. I further test various load models against the GNSS observations. Our research further investigates the impact of local crustal properties and evaluates the output of several elastic loading models using crustal properties and different model types under non-drought and drought conditions. For future studies, I suggest a comprehensive analysis of the deformation field InSAR data. Also, rigorous monitoring of groundwater levels is essential to accurately predict changes in water masses based on deformation. In addition, for each data set, I suggest implementing an uncertainty analysis to assess the predictability of groundwater level changes based on vertical loading deformation observed by INSAR/GNSS data around the region. Obtaining such estimates will provide valuable insight into the dynamic interactions of the local aquifers with Lake Mead. / Master of Science / The drought has led to a decline of approximately 40 meters in Lake Mead since 1999. During the process of water mass loss from a lake, the crust lifts and extends from the center. However, the water mass loss seen on the lake is not sufficient to explain the movement seen at nearby GPS sites. Hence, the uplift loading of water loss in the form of other hydrological components surrounding Lake Mead needs to be estimated. Here, I analyze several models that best fit the geodetic displacements and try to fill in the gap in deformation observations.
73

A computational framework for analyzing chemical modification and limited proteolysis experimental data used for high confidence protein structure prediction

Anderson, Paul E. 08 December 2006 (has links)
No description available.
74

An Analysis of President Trump's Afghanistan Foreign Policy: Through the Theoretical Framework of Walter Russell Mead's Four Paradigms

Santoro, Patrick Thomas 26 May 2020 (has links)
The purpose of this thesis was to analyze President Trump's Afghanistan foreign policy and to determine if it fits the mold of one of the four historical foreign policy paradigms as described by Walter Russell Mead in his book, Special Providence: American Foreign Policy and How It Changed the World. Mead describes four U.S. foreign policy schools of thought, in which he titles after influential statesmen who embody the specific school's core principles. These paradigms include the Hamiltonians, who believe in a strong relationship between big business and government for foreign policy success. The Wilsonians, who encourage the spread of democratic principles abroad. The Jeffersonians, who favor the protection of domestic liberal democracy over other foreign policy endeavors. Lastly, the Jacksonians, who prioritize the physical and economic security of American citizens above all else. The primary research question in this thesis states, which of the four traditions of U.S. foreign policy identified by Walter Russell Mead helps explain President Trump's Afghanistan foreign policy? President Trump's rhetoric and specific foreign policy actions were analyzed. His rhetoric was examined through his August 2017 Afghanistan Strategy speech and his specific foreign policy actions were measured through various air operation metrics, U.S. aid to Afghanistan, and U.S. troop deployment trends. Overall, this thesis gave support to my hypothesis that President Trump's Afghanistan foreign policy contains various Hamiltonian and Wilsonian principles, but it has proven to be principally Jacksonian. / Master of Arts / The objective of this thesis was to further understand President Trump's Afghanistan foreign policy through the theoretical framework of Walter Russel Mead's four historical foreign policy paradigms. Mead's four historical paradigms are useful tools to examine and understand U.S. foreign policy. Mead provides in-depth historical context, goes into great detail on core principles, and also provides a surfeit of advantages and disadvantages for each school of thought. His breakdown of U.S. foreign policy into complementary yet combative paradigms is one of the most complete explanations of U.S. foreign policy to date. The primary research question in this thesis states, which of the four traditions of U.S. foreign policy identified by Walter Russell Mead helps explain President Trump's Afghanistan foreign policy? President Trump's rhetoric and specific foreign policy actions were analyzed. His rhetoric was examined through his August 2017 Afghanistan Strategy speech and his specific foreign policy actions were measured through various air operation metrics, U.S. aid to Afghanistan, and U.S. troop deployment trends. Overall, this thesis gave support to my hypothesis that President Trump's Afghanistan foreign policy contains various Hamiltonian and Wilsonian principles, but it has proven to be principally Jacksonian.
75

Construction d'une chaîne d'outils numériques pour la conception aérodynamique de pales d'éoliennes / Construction of a numerical tool chain for aerodynamical conception of wind turbine blades

Jin, Xin 19 September 2014 (has links)
Ce mémoire présente les travaux réalisés en aérodynamique afin de pouvoir disposer d’une chaîne de conception complète nécessaire au traitement des différentes problématiques sur les pales éoliennes, qui ne peuvent être pris en compte à l’aide d’une méthode unique. Afin de pouvoir faire de l’optimisation de pales en fonction de différents critères, un outil numérique simplifié (VALDAG) a été développé. Le module de simulation utilise la méthode du Disque Actif Généralisé, qui s’appuie sur la résolution des équations Navier-Stokes, complété par des corrections empiriques. Il respecte un compromis entre la précision et le coût de calcul. Cet outil pour lequel une interface web a été développée pour le rendre adapté à des travaux d’ingénierie est susceptible de se calibrer automatiquement sur une nouvelle géométrie de pale grâce à la méthode Nelder-Mead Simplex. On peut ensuite réaliser une optimisation de la performance de la pale en modifiant cette géométrie, et générer les fichiers 3D qui serviront d’entrée à la simulation 3D et de visualisation des optimisations de forme. Ces designs optimisés sont ensuite validés par des simulations DNS à l’aide de l’outil NaSCar 3D développé à l’INRIA. Cet outil résout des équations Navier-Stokes sur un maillage cartésien 3D et prend en compte des obstacles immergés via la fonction Level-Set et la pénalisation. Après des adaptations sur le traitement de la géométrie de pales, un compromis de configuration CFD est trouvé pour simuler un rotor éolien. En conclusion, ce paquet d’outils VALDAG est peu coûteux, facile à utiliser et efficace. En associant VALDAG aux simulations 3D, une chaîne de conception est complétée. / This Ph.D. thesis presents some research work on aerodynamics of wind turbine blades, in order to dispose a conception chain necessary for different problems, which cannot be treated by one unique method. A simplified numerical toolkit (VALDAG) has been developed to optimize the performance of blades in different creteria. The simulation module use the Generalized Actuator Disc model, which relies on the solution of Navier-Stokes equations and completed with empiric corrections. This tool respects a reasonable compromise between model complexity and computational reliability. An automatic calibration mechanism was implemented using the Nelder-Mead Simplex algorithm. A web users interface (WUI) is also available to adapt VALDAG for industrial engineers. Optimization is then carried on by modifying the blades’ geometry parameters and the designs optimized is stocked in files which can be used for 3D simulation and/or visualization. The blade designed with VALDAG are then simulated by a 3D numerical tool to validate previous predictions. This 3D tool called NaSCar 3D is developed in INRIA and resolve Navier-Stokes equations on to a cartesian mesh, in which the immersed obstacles are considered with the Level-Set function and the penalization method. After some necessary adaptation for the treatment of blades’ geometry, a compromise on CFD configuration is found to simulate a wind turbine rotor. To conclude, this design toolkit VALDAG is low time-costly, user-friendly and efficient. Associated with 3D simulations, a conception chain has been established.
76

ROTEAMENTO AUTOMÁTICO DE ALIMENTADORES NO PLANEJAMENTO DE SISTEMAS DE DISTRIBUIÇÃO DE ENERGIA ELÉTRICA / AUTOMATIC ROUTING OF FOOD IN PLANNING SYSTEMS DISTRIBUTION OF ELECTRIC ENERGY

ROCHA, Adson Silva 07 November 2008 (has links)
Made available in DSpace on 2014-07-29T15:08:22Z (GMT). No. of bitstreams: 1 Adson.pdf: 1251737 bytes, checksum: 08b3122009f15a40cec4f32fda3231e9 (MD5) Previous issue date: 2008-11-07 / The present work deals with the problem of planning the distribution system of electricity and is divided into three parts: Problem Definition, Resolution Approaches and Results and Conclusions. The energy distribution networks are of great economic importance in countries like Brazil. On one hand, there are fixed costs of physical installation and operation of the network, mainly due to the costs of energy losses and, secondly, the natural obstacles along the possible passages of network s links. The large amount of these costs, together with lack of efficient methods when it comes to real applications in the matter, justify the development of this research. The study of such aspects, the precise definition of the problem and the reasons that motivated this work can be found on the first part of this work. The second part shows the approaches for resolution. Three proposals methods were adopted: the first uses the algorithm Prim associated with the method Nelder-Mead Simplex. In the second proposal uses Dynamic Programming and, finally, we take the metaphor of Ant Colony also associated with the Nelder-Mead Simplex. The results, presented at the third part of this work, demonstrated the effectiveness of the proposed methods, especially the good compromise between performance and applicability obtained by the third proposal. / O presente trabalho lida com o problema de planejamento da rede de distribuição de energia elétrica, estando dividido em três partes: Definição do Problema, Abordagens de Resolução e Resultados e Conclusões. As redes de distribuição de energia têm uma grande importância econômica em países como o Brasil. Por um lado, há os custos físicos fixos de instalação e de operação da rede, sobretudo os custos devido às perdas de energia e, por outro, os obstáculos naturais impostos ao longo das possíveis passagens para as ligações da rede. O montante elevado destes custos, unidos à escassez de métodos eficientes quando se trata de aplicações reais no assunto, justificam o desenvolvimento desta pesquisa. O estudo de tais aspectos, a definição precisa do problema e as justificativas podem ser encontradas na primeira parte deste trabalho. Na segunda parte, apresentam-se as abordagens de resolução. Três propostas foram adotadas: na primeira usa-se o algoritmo Prim associado ao método Nelder-Mead Simplex. Na segunda proposta utiliza-se a Programação Dinâmica e, por fim, tomamos a metáfora de colônia de formigas também associada ao Nelder-Mead Simplex. Os resultados, apresentados na terceira parte deste trabalho, mostram a eficácia dos métodos propostos, em especial o bom compromisso entre performance e aplicabilidade obtido pela terceira proposta.
77

Filtrace svalového rušení v EKG signálech / Muscle noise filtering in ECG signals

Novotný, Jiří January 2015 (has links)
This master's thesis deals with the optimization of numerical coefficients of the Wiener filter for muscle noise filtering in ECG signals. The theoretical part deals with ECG signal characteristic and muscle interference. It also contains a summary of the wavelet transform, wavelet Wiener's filtration, methods for calculating of the threshold and thresholding. In the last theoretical part the characteristic optimization techniques, the exhausive search and Nelder-Mead simplex method are mentioned, which were implemented in the practical part of this thesis in MATLAB. The functional verification and Wiener's filter optimization were tested on the standard electrocardiograms database CSE. By using the methods of exhausive search, the initial estimate for the solution method Nelder-Mead was obtained. The optimization method Nelder-Mead gives better results in the orders of hundredths or tenths than the method of exhausive search. The practical part is finished by the comparison of results of implemented algorithm with optimum coefficients, implemented in this thesis, with the results of other methods for filtering muscle interference in ECG signals.
78

EXTERNAL PUBLIC PIANO EXAMINATIONS IN MALAYSIA: SOCIAL AND SYMBOLIC SIGNIFICANCE

Ross, Valerie, kimg@deakin.edu.au 3 October 2002 (has links)
The thesis investigated the social and symbolic significance of acquiring a 'music education' through the taking of piano tuition and external public music examinations. It aimed to discover why the learning of the piano and the certification of musical attainment are so prevalent and revered among Malaysian music students. Its purpose was to unravel the socio-cultural raison d'etre of this approach to music education through the creation of a metatheoretical schema, which is premised upon the theories of symbolic interactionist, George Herbert Mead, music analyst, Heinrich Schenker and social theorist, George Ritzer. Central to the argument in this instance is the symbolic significance associated with the act of playing the piano. The investigation attempted to determine if this 'act' conveyed a symbolic meaning that is peculiar to a specific cultural vista. It further examined the degree to which this practice represented both a validation and a sense of conformity to social norms in the continuity and stability of an expanding middle class society in Malaysia. The Associated Board of the Royal Schools of Music (ABRSM) is the largest of the five main external public music examination boards that operate in Malaysia. Since 1948, over one million candidates have enrolled for ABRSM examinations in Malaysia and a team of approximately thirty ABRSM examiners visit Malaysia for three months every year. The majority of the candidates are pianists. Given such large numbers of piano candidates, one might expect a healthy development of musical talent in the country with aspiring pianists eager to demonstrate their musical prowess. However, this does not seem to be the case. On the contrary, there appears to be a curious lacuna between the growing number of students who enrol for external public music examinations and the seemingly lack of interest in public music making and the honing of general musicianship skills. The thesis hence examined the symbolic meaning of this socio-rausicological phenomena.
79

External public piano examinations in Malaysia: Social and symbolic significance.

Ross, Valerie, mikewood@deakin.edu.au January 2002 (has links)
The thesis investigated the social and symbolic significance of acquiring a 'music education' through the taking of piano tuition and external public music examinations. It aimed to discover why the learning of the piano and the certification of musical attainment are so prevalent and revered among Malaysian music students. Its purpose was to unravel the socio-cultural raison d'etre of this approach to music education through the creation of a metatheoretical schema, which is premised upon the theories of symbolic interactionist, George Herbert Mead, music analyst, Heinrich Schenker and social theorist, George Ritzer. Central to the argument in this instance is the symbolic significance associated with the act of playing the piano. The investigation attempted to determine if this 'act' conveyed a symbolic meaning that is peculiar to a specific cultural vista. It further examined the degree to which this practice represented both a validation and a sense of conformity to social norms in the continuity and stability of an expanding middle class society in Malaysia. The Associated Board of the Royal Schools of Music (ABRSM) is the largest of the five main external public music examination boards that operate in Malaysia. Since 1948, over one million candidates have enrolled for ABRSM examinations in Malaysia and a team of approximately thirty ABRSM examiners visit Malaysia for three months every year. The majority of the candidates are pianists. Given such large numbers of piano candidates, one might expect a healthy development of musical talent in the country with aspiring pianists eager to demonstrate their musical prowess. However, this does not seem to be the case. On the contrary, there appears to be a curious lacuna between the growing number of students who enrol for external public music examinations and the seemingly lack of interest in public music making and the honing of general musicianship skills. The thesis hence examined the symbolic meaning of this socio-musicological phenomena.
80

Mäns identitetsskapande på en kvinnodominerad arbetsplats

Ghassemi, Nima January 2010 (has links)
<p>Syftet med föreliggande studie är att utifrån ett individperspektiv erhålla djupare förståelse och ökad insikt inom ramen för mäns identitetskapande på en kvinnodominerad arbetsplats. Studien utgick från en kvalitativ metod med en tematisk, semistrukturerad intervjuguide. Urvalet utgjordes av fyra män som jobbar på ett sjukhus i Halmstad. Resultatet visar att männens identitet är flyktig och att den är situationsbunden. Resultatet påvisar även hur en identitet är bunden till olika slags sociala relationer.Resultatet analyseras utifrån George Herbert Mead, Sigmund Freud, Erwig Goffman, William James samt Gregory Stone. Analysen berör aspekterna; maskulin identitet, rollskiftningar samt vad en identitet innebär.</p>

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