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Hur får man tyst på en gitarrist? : En observationsstudie i a-°©‐vistaläsning / How do you make a guitarist stop playing? : An observational study in sight readingGunnarsson, Andreas January 2014 (has links)
Studiens syfte är att se ifall det är möjligt att under en kortare tid bli en bättre a-vistaläsare. För att undersöka detta har jag under en åttaveckorsperiod övat a-vista 15 minuter per dag, med hjälp av en bok just för a-vistaläsning. Ett urval av dessa övningstillfällen har jag videofilmat. Jag har också använt mig av loggbok för att dokumentera mina upplevelser av min egen process. Som teoretisk utgångspunkt har jag valt ett multimodalt designteoretiskt perspektiv. I resultatet visas hur olika resurser hanteras, samt hur progression i lärandet har varit. Det framkommer att jag under denna period har lärt mig att läsa a-vista bättre än innan. Jag använde mig av kroppsliga resurser i ganska stor utsträckning då jag övade a-vistaläsning. I diskussionen beskriver jag utifrån det designteoretiska perspektivet hur förutsättningarna utifrån den valda boken har varit, samt vilka resurser som användes vid lärandet. / The purpose of this study is to find out if it is possible to become better at sight-reading melodies during a shorter period, in this case eight weeks with 15 minutes of daily training. With a video recorder, I have documented a selection of daily training sessions based on a book that specifically focuses on sight-reading melodies. Furthermore, I have written a logbook to document my personal experiences during the process. Theoretical perspective is design theory. The results shows how different resources are handled, and the learning progression of the process are described. It appears that I during this period, have become better at sight-reading melodies and it is also clear that I use bodily resources quite a lot while practicing sight-reading. Lastly, in the last chapter I discuss the preconditions given by the book and what resources that has been created during my learning period.
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Glacial geology and glaciology of the Younger Dryas ice cap in ScotlandGolledge, Nicholas Robert January 2009 (has links)
This thesis uses geological field data and numerical ice sheet modelling to study the Younger Dryas ice cap in Scotland. The Younger Dryas stadial is important because it represents the most recent period of high-magnitude global climate change, and was marked by the expansion of ice sheets in North America and Scandinavia, and the regrowth of glaciers in the British Isles. An integrated methodology linking field results and modelling is developed and applied here, specifically focussing on the deposits, landforms, and palaeoglaciology of Younger Dryas glaciers in western Scotland. This combined approach enables data of different scales to be compared, and connected, from local sedimentological investigations and empirically derived reconstructions, to regional ice-sheet simulations from a high-resolution numerical model. Previous geological mapping in western Scotland resulted in contradictory views of the thickness and extent of ice during the Younger Dryas, consequently leading to uncertainty about the dynamics of the former ice cap. By using a ‘landsystem’ method to characterise the terrain, it is argued here that geological evidence in the study area implies a relatively thick central ice cap that fed steep outlet glaciers around its margins. These glaciers oscillated throughout the stadial, and during deglaciation produced suites of moraines that marked successive positions of glacier retreat. Widespread preservation of superimposed landforms, and of sediment sequences pre-dating the Younger Dryas, suggest that, despite being active, the Younger Dryas ice cap was not particularly erosive in its central area and only subtly modified its bed. These geological interpretations are supported by high-resolution numerical modelling of the ice cap, which reveals clear spatial variability in the velocity structure, thermal regime, and flow mechanism of the ice cap; patterns that led to local contrasts in basal processes and diversity in the geological imprint. These model experiments also highlight the non-linear relationship between climate forcing and glacier response, identifying evidence of ice sheet hysteresis and climatically decoupled glacier oscillations – concepts as relevant to geological investigations of former ice masses as they are to the prediction of glacier response under future climate changes.
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Modelling the hydrology of the Greenland ice sheetKaratay, Mehmet Rahmi January 2011 (has links)
This thesis aims to better understand the relationships between basal water pressure, friction, and sliding mechanisms at ice sheet scales. In particular, it develops a new subglacial hydrology model (Hydro) to explicitly predict water pressures in response to basal water production and water injection from the surface. Recent research suggests that the Greenland ice sheet (gis) is losing a substantial volume of ice through dynamic thinning. This process must be modelled to accurately assess the contribution of the gis to sea-level rise in future warming scenarios. A key control on dynamic thinning is the presence of water at the ice-bed interface; Zwally et al. (2002) highlight the importance of supraglacial lakes' impact on basal ice dynamics, a process now con rmed by Das et al. (2008) and Shepherd et al. (2009). Many studies focus on the effects of surface meltwater reaching the bed of the gis but the underlying processes are often ignored. Geothermal, strain, and frictional melting, which evolves with basal hydrology, provide the background basal pressure profile that surface meltwater perturbates. Without understanding how these heat terms affect the background profile it is difficult to define basal boundary conditions in models and therefore difficult to model the dynamic response of the gis to surface melting. Hydro tracks subglacial water pressures and the evolution of efficient drainage networks. Coupled with the existing 3D thermomechanical ice sheet model Glimmer, model outputs include effective pressure N and the efficient hydraulic area. Defining frictional heat flux and basal traction as functions of N allow the modelling of seasonal dynamic response to randomly draining supraglacial lakes. Key results are that frictional heat flux, as a function of N, caps potential runaway feedback mechanisms and that water converges in topographic troughs under Greenland's outlet glaciers. This leads to a background profile with low N under outlet glaciers. Therefore, outlet glaciers show a muted dynamic speedup to the seasonal surface signal reaching the bed. Land-terminating ice does not tend to have subglacial troughs and so has higher background N and consequently a larger seasonal response. This, coupled with effects of ice rheology, can explain the hitherto puzzling lack of observed seasonal velocity change on Jakobshavn Isbræ and other outlet glaciers.
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Mountain centered icefields in northern ScandinaviaFredin, Ola January 2004 (has links)
Mountain centered glaciers have played a major role throughout the last three million years in the Scandinavian mountains. The climatic extremes, like the present warm interglacial or cold glacial maxima, are very short-lived compared to the periods of intermediate climate conditions, characterized by the persistence of mountain based glaciers and ice fields of regional size. These have persisted in the Scandinavian mountains for about 65% of the Quaternary. Mountain based glaciers thus had a profound impact on large-scale geomorphology, which is manifested in large-scale glacial landforms such as fjords, glacial lakes and U-shaped valleys in and close to the mountain range. Through a mapping of glacial landforms in the northern Scandinavian mountain range, in particular a striking set of lateral moraines, this thesis offers new insights into Weichselian stages predating the last glacial maximum. The aerial photograph mapping and field evidence yield evidence that these lateral moraines were overridden by glacier ice subsequent to their formation. The lateral moraines were dated using terrestrial cosmogenic nuclide techniques. Although the terrestrial cosmogenic nuclide signature of the moraines is inconclusive, an early Weichselian age is tentatively suggested through correlations with other landforms and stratigraphical archives in the region. The abundance and coherent spatial pattern of the lateral moraines also allow a spatial reconstruction of this ice field. The ice field was controlled by topography and had nunataks protruding also where it was thickest close to the elevation axis of the Scandinavian mountain range. Outlet glaciers discharged into the Norwegian fjords and major valleys in Sweden. The process by which mountain based glaciers grow into an ice sheet is a matter of debate. In this thesis, a feedback mechanism between debris on the ice surface and ice sheet growth is presented. In essence, the growth of glaciers and ice sheets may be accelerated by an abundance of debris in their ablation areas. This may occur when the debris cover on the glacier surface inhibits ablation, effectively increasing the glaciers mass balance. It is thus possible that a dirty ablation area may cause the glacier to advance further than a clean glacier under similar conditions. An ice free period of significant length allows soil production through weathering, frost shattering, and slope processes. As glaciers advance through this assemblage of sediments, significant amounts of debris end up on the surface due to both mass wastage and subglacial entrainment. Evidence that this chain of events may occur, is given by large expanses of hummocky moraine (local name Veiki moraine) in the northern Swedish lowlands. Because the Veiki moraine has been correlated with the first Weichselian advance following the Eemian, it implies a heavily debris charged ice sheet emanating from the mountain range and terminating in a stagnant fashion in the lowlands.
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Reconstruction of the Late Pleistocene and Holocene geomorphology of northwest Calvert Island, British ColumbiaEamer, Jordan Blair Reglin 24 April 2017 (has links)
This dissertation presents results from a multi-year interdisciplinary study of the Late Quaternary geomorphic history of northwest Calvert Island, British Columbia, Canada. There is a considerable knowledge gap in the region pertaining to Cordilleran ice cover and extent as well as landscape response to a uniquely stable relative sea-level history. The objective of this study was to reconstruct this regional landscape response to deglaciation including post-LGM ice cover and extent, relative sea-level changes, coastal landform development, and climate and ecological variance. Methods used to inform this reconstruction included airborne lidar, aerial photography interpretation, sedimentary stratigraphy and detailed sedimentology of samples from shovel pits and lake cores, surficial geology and geomorphic mapping, palaeoecological examinations, and the development of a geochronology using radiocarbon and optical dating. To assist with landscape reconstruction, a new method was developed and used to differentiate littoral and aeolian sands in sediment samples that range in age from Mid to Late Holocene by using modern reference samples. The method utilized a standard optical microscope paired with freely available software (ImageJ) to characterize grain shape parameters. The method was tested on nearly 6,000 sand grains from samples of known and hypothesized depositional settings and was able to correctly identify the depositional setting for 76% of the samples. After testing, the method was used to differentiate littoral and aeolian sands in a number of shovel pit, exposure, and core sediment samples to give context to stratigraphic and geomorphic interpretations. A short-lived Late Pleistocene re-advance of Cordilleran ice occurred in the study area, with radiocarbon ages indicating ice advanced to, and then retreated from, the western edge of Calvert Island between 14.2 and 13.8 ka cal BP, respectively. Sedimentological and palaeoecological information that suggests a cold climate and advancing/retreating glacier as well as lidar remote sensing and field-based geomorphic mapping of moraines in the region provide evidence of the re-advance. After ice retreated from the area, a broad suite of geomorphic landforms developed, including flood plains,
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aeolian dunes, beaches, spits, marshes, and tombolos. Coastal reworking was extensive, with progradation rates greater than 1 m a-1 occurring in some locations during the Late Holocene. These data provide the first evidence of a re-advance of the retreating ice sheet margin on the central coast of British Columbia, contribute an important methodology to advance Quaternary reconstructions, and give a unique account of the geomorphic development of a Pacific Northwest coastline that experienced little relative sea-level change over the Late Pleistocene and Holocene. Results help fill a spatial and temporal gap in the landscape history of British Columbia and have implications for climate and sea-level reconstructions, early human migration patterns, and the palaeoenvironment of an understudied area of the Pacific Northwest coast of North America. / Graduate / 0368 / 0372 / 0426 / jeamer7@gmail.com
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Effects of membrane structure and operational variables on membrane distillation performanceKaranikola, Vasiliki, Corral, Andrea F., Jiang, Hua, Sáez, A. Eduardo, Ela, Wendell P., Arnold, Robert G. January 2017 (has links)
A bench-scale, sweeping gas, flat-sheet Membrane Distillation (MD) unit was used to assess the importance of membrane architecture and operational variables to distillate production rate. Sweeping gas membrane distillation (SGMD) was simulated for various membrane characteristics (material, pore size, porosity and thickness), spacer dimensions and operating conditions (influent brine temperature, sweep gas flow rate and brine flow rate) based on coupled mass and energy balances. Model calibration was carried out using four membranes that differed in terms of material selection, effective pore size, thickness and porosity. Membrane tortuosity was the lone fitting parameter. Distillate fluxes and temperature profiles from experiments matched simulations over a wide range of operating conditions. Limitations to distillate production were then investigated via simulations, noting implications for MD design and operation. Under the majority of conditions investigated, membrane resistance to mass transport provided the primary limitation to water purification rate. The nominal or effective membrane pore size and the lumped parameter epsilon/delta tau (porosity divided by the product of membrane tortuosity and thickness) were primary determinants of membrane resistance to mass transport. Resistance to Knudsen diffusion dominated membrane resistance at pore diameters <0.3 mu m. At larger pore sizes, a combination of resistances to intra-pore molecular diffusion and convection across the gas-phase boundary layer determined mass transport resistance. Findings are restricted to the module design flow regimes considered in the modeling effort. Nevertheless, the value of performance simulation to membrane distillation design and operation is well illustrated.
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Využití účetních výkazů k posouzení finanční situace podniku / Use of account sheet to evaluate the financial position of the companyKováříková, Jana January 2010 (has links)
The aim oh the diploma thesis is to analyse the financial situation of a company on the base of account sheet. In theoretical part there is a description and explication of processes and methods of financial analysis including the description of source of information suitable for financial analysis. There is as well the description and analysis of the financial statements constructed according to the Czech rules and according to the International financial reporting standards IAS/IFRS. In practical part of this thesis there is the aplication of the processes and methods of financial analysis to evaluation the financial position of the company Elitex Nepomuk a.s. based on the period since 2002 to 2008. The conclusion of this thesis contains the summary of the history and the present condition of the financial position of the company Elitex Nepomuk a.s. There is also the evaluation of the financial health oh this company based on the outcomes of the financial analysis.
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Investigating aluminum plate with different geometrical shape by using DIC tension testYang, Peng January 2019 (has links)
This subject mainly uses Aluminum sheet metal material as the research object which is used in Volvo XC90 door, the elastic plasticity deformation within the different material angles and notch shape investigated with MTS tensile test equipment under uniaxial tension. The local strain curve studied by using DIC method to obtain the conventional physical quantity. Combining ABAQUS to analyze the distribution of stress in elastic and plastic regions, also use MATLAB to combine various parameters, and finally analyze the desired experimental results to find a relatively stable notch shape based on the yield curve and stress concentration factor.
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Business combination e consolidação: uma abordagem comparativa entre as normas dos US-GAAP, IASC e Brasil / Business combination and consolidation: a comparative analysis among the US-GAAP, IASC and Brazilian accouting pronoucementsHajj, Zaina Said El 08 September 1999 (has links)
Este estudo apresenta uma abordagem comparativa entre as normas contábeis dos US-GAAP, IASC e Brasil para as operações de business combination e para a consolidação das demonstrações contábeis. Define-se business combination de acordo com os conceitos contidos nos US-GAAP, IASC e nos pronunciamentos brasileiros para em seguida apresentar a definição adotada neste estudo. Precedendo a metodologia desta pesquisa, este estudo apresenta algumas estatísticas das operações de business combination e as abordagens das principais dificuldades relacionadas ao tema, assim como se levanta a questão nevrálgica para o estudo. Nos capítulos denominados US-GAAP, IASC e Brasil são tratadas as principais normas contábeis emitidas, destacando-se as definições, o tratamento contábil, métodos de avaliação, consolidação e evidenciações exigidas. Em seguida são esclarecidas na análise comparativa algumas das principais similaridades e diferenças abordadas nos capítulos anteriores. O estudo inclui uma análise dos mais significativos procedimentos de consolidação e apresenta exemplos relativos a cada entidade analisada. Finalmente, as conclusões realizadas na referida análise. / This study presents a comparative analysis among the US-GAAP, IASC and Brazilian accounting pronoucements for the transactions of business combination and for the consolidation of financial statements. It reviews the definition of business combination according to the concepts of US-GAAP, IASC and Brazilian pronouncements and, subsequently, the definition used in this study. Preceding the methodology of this research, this study offers some statistics of the transactions of business combination and gives a survey of how the main difficulties related to this subject were approached, as well as a determination of the most important issue of this study. In the chapters named US-GAAP, IASC and Brazil, the main rules of accountancy are trated, highlighting the definitions, accounting treatment, methods of evaluation, consolidation and disclosure. Moreover, in the comparative analysis, some of the main similarities and differences are cleared up that were shown in the previous chapters. This study includes an analysis of the most significant procedures for consolidation, as well as some examples related to each of the institutions that were focused on. Finally, the conclusions that were made on the basis of analysis are discussed.
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Estudo do processo de fabricação de alvos de folhas finas de urânio metálico para produção de Mo-99 / Study of the process of fine metallic uranium sheet targeting for Mo-99 productionSouza, José Antonio Batista de 05 October 2018 (has links)
O Tecnécio-99m (99mTc), gerado a partir do decaimento do Molibdênio-99 (99Mo), é o radionuclídeo mais conveniente para a execução de procedimentos de diagnósticos médicos, devido à sua emissão gama bem característica e de fácil detecção. O método utilizado para produzir 99Mo é através da fissão do 235U incorporado nos chamados alvos de irradiação. Duas rotas estão sendo desenvolvidas para a produção do 99Mo por fissão para o Reator Multipropósito Brasileiro (RMB), ambas utilizando urânio de baixo enriquecimento (LEU): 1) A primeira a dissolução básica, que é baseada na tecnologia de alvos de dispersão UAlx-Al. 2) A segunda emprega a dissolução ácida de alvos de folhas finas de urânio metálico. A principal vantagem dos alvos de folha fina de urânio metálico sobre os alvos de dispersão UAlx-Al é a alta densidade do urânio metálico. Com o intuito de compreender e otimizar o processo de fabricação de alvos de folhas finas foi realizado um estudo da fusão do urânio metálico, laminação de folhas finas, caracterização microestrutural e montagem dos alvos, definindo assim, os procedimentos específicos para a produção desse tipo de alvo com as características dos alvos fabricados internacionalmente. Os resultados obtidos mostraram que o processo de fabricação dos lingotes e de lâminas de urânio metálico por meio de laminação a quente possibilitaram a obtenção de lâminas com espessura entre 250 e 300 μm. O processo de laminação a frio possibilitou a obtenção de folhas finas com espessura de ±125 μm que atende à especificação internacional. O uso de óxido de alumínio como material para prevenir caldeamento do tablete de urânio mostrou-se eficiente, substituindo com vantagens o uso de óxido de ítrio. A microestrutura após o tratamento térmico apresentou grãos equiaxiais pequenos, e a realização de um resfriamento rápido de 5 minutos após o tratamento térmico foi suficiente para se eliminar a textura da folha fina de urânio metálico. O processo de montagem das folhas finas no alvo tubular foi realizado por pré-conformação da folha fina, facilitando a montagem. O processo de consolidação do alvo foi realizado por expansão por tração e a folga após a consolidação (\"gap de ar\") mostrou-satisfatória. As dimensões finais dos alvos tubulares atenderam à especificação internacional. / Technetium-99m (99mTc) is generated from the decay of Molybdenum-99 (99Mo). This element is the most convenient radionuclide for application in medical diagnostic procedures, once that its gamma emission is well known and of easily detected. The method used to produce 99Mo is through fission of the 235U embedded in so-called irradiation targets. Two routes are being developed for the production of 99Mo per fission to the Brazilian Multipurpose Reactor (RMB), both using low enriched uranium (LEU): 1) The first basic dissolution, which is based on the technology of dispersion targets UAlx-Al. 2) The second employs the acidic dissolution of thin sheet targets of metallic uranium. The main advantage of uranium metal foil targets on the UAlx-Al dispersion targets is the high density of metallic uranium. In order to understand and optimize the process of manufacturing thin sheet targets, about the fusion of metallic uranium, thin sheet lamination, microstructural characterization and assembly of the target was carried out. Therefore the specific procedures for the production of this type of target with the characteristics of the targets manufactured internationally could be defined. The results showed that the process of manufacturing ingots and sheets of metallic uranium by hot rolling allows obtaining sheets with thickness between 250 and 300 μm. The cold rolling process allows obtaining thin sheets with a thickness of ± 125 μm which are in accordance with the international specification. The use of aluminum oxide as a material to prevent uranium tablet firing proved to be efficient, replacing with advantage the use of yttrium oxide. The microstructure after the heat treatment showed small equiaxial grains. A fast cooling of 5 minutes after the heat treatment was enough to eliminate the texture of the thin sheet of metallic uranium. The process of assembling the thin sheets in the tubular target was performed by preforming the thin sheet, facilitating the assembly. The process of consolidating the target was performed by tensile expansion and the clearance after consolidation (\"air gap\") was satisfactory. The final dimensions of the tubular targets have met the international specification.
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