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Predictability of Current and Future Multi-River discharges: Ganges, Brahmaputra, Yangtze, Blue Nile, and Murray-Darling RiversJian, Jun 16 October 2007 (has links)
The aim of this study is to determine the predictability of river discharge in several major rivers on time scale varying from weeks to a century.
We investigated predictability considering relationship between SST and Ganges and Brahmaputra River discharge. On seasonal time scales, statistically significant correlations are found between monthly equatorial Pacific SST and the summer Ganges discharge with lead times of 2-3 months due to oscillations of the ENSO phenomena. In addition, there are strong correlations in the southwest and northeast Pacific. The Brahmaputra discharge shows weaker relationships with tropical SST. Strong correlations relationships are found with SST in the Bay of Bengal but these are the result of very warm SSTs and exceptional Brahmaputra discharge during the summer of 1998. When this year is removed, relationships weaken everywhere except in the northwestern Pacific for the June and July discharge.
Second goal is to project the behavior of future river discharge forced by the increasing greenhouse gases and aerosols from natural and anthropogenic sources. Three more rivers, the Yangtze, Blue Nile, and Murray-Darling rivers are considered. The original precipitation output from CMIP3 project has large inter-model variability, which limits the ability to quantify the regional precipitation or runoff trends.
With a statistical Quantile-to-Quantile (Q-Q) technique, a mapping index was built to link each modeled precipitation and observational discharge. We also use the climatological annual cycle to choose the ¡°good¡± models. With the same indices, the future 21st century discharges of the first four rivers are simulated under different SRES scenarios. The Murray-Darling River basin does not have the similar seasonal cycle of discharge with modeled precipitations. We choose to project basin averaged precipitations instead.
The Yangtze, Ganges, Brahmaputra River mean wet season discharges are projected to increase up to 15-25% at the end of the 21st century under A1B and A2. The risks of flooding also reach to a high level throughout the time. Inter-model deviations increase dramatically under all scenarios except for COMMIT. With large uncertainty, the Blue Nile River discharge and Murray-Darling River basin annual precipitation do not suggest a sign of change on multi-model mean.
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Temporal variations of monsoon systemsVieira Agudelo, Sara C. 09 September 2010 (has links)
It has been proposed that the Asian-Australasian monsoon system is influenced by large-scale sea-surface temperature (SST) variability in the three tropical oceans although how this influence is manifested has remained a largely open question. Closure of this issue is important because it is needed to explain trends in monsoon precipitation and circulation that have occurred in the last 30 years. Using an atmospheric general circulation model, we run a series of experiments with different configurations of global SST relating to various epochs occurring during the last century to evaluate their influence on the monsoon. Comparisons of circulation fields show that a colder SST configuration generates a weaker large-scale monsoonal circulation. On the other hand, warmer SST states generate stronger large scale circulations with more vigorous centers of divergence and convergence. Warmer SST configurations are associated with positive anomalies of precipitation in the eastern Bay of Bengal, Eastern Indian Ocean and South East Asia. Cooler SST configurations are associated with negative anomalies of precipitation in the Arabian Sea and Indian peninsula, especially at the beginning of the summer. Since SST gradients determine, to a large degree, the low level flow, they are also going to influence the transport of atmospheric moisture. Comparison of vertically integrated moisture transport fields between the different experiments show that cold SST configuration favors an increased inter-hemispheric flow of moisture but decreases in the westerly moisture flow in to the Bay of Bengal and India. Warm SST configurations, on the other hand, strengthens westerly flow into the eastern Indian Ocean. An increasing availability of moisture in a region of stronger convergence constitutes a favorable environment for the production of monsoonal precipitation.
African easterly waves (AEW) constitute an important component of the African and tropical Atlantic Ocean climate during the boreal summer. An understanding of this component is essential since AEW are closely related with tropical Atlantic storm activity. We adopt an idealized modeling approach using the WRF model initialized with ERA-40 reanalysis data to study the mechanisms that trigger the formation and maintenance of AEW. The model domain includes the African continent, central and eastern Atlantic Ocean and the western Indian Ocean. Experiments are designed to test the relative importance of the thermal effect of the eastern African topography and the influence of the cross-equatorial pressure gradient, induced by the sea surface temperature (SST) on the origins and maintenance of AEW. Topography and SST variation are selectively added and removed. The control experiment shows that the model reproduces many of the mean features observed during the boreal summer. Westward propagating disturbances of 3-8 day period that originate between 30 and 40E at the surface levels and in the mid troposphere are well depicted. In addition, the model provides a reasonable representation of the AEJ.
When all topographic features are removed, there is a weakening of the AEJ over land and ocean, however, longitude-time sections of meridional velocity still exhibit westward propagating disturbances that reach the western African coast at the surface and at the jet level with the same 3-8 day period. Spectral analysis of meridional velocity show that the variability associated with AEWs is reduced over East Africa and West Africa at 850-hPa and is reduced west of 20E along the southern flank of the jet and over northern Africa at the jet level. Maximum amplitude of the disturbances occurs right at the coast. The spatial distribution of barotropic and baroclinic energy conversions explains the reduction in AEWs over land and the intensification of these features at the coast.
When the zonal SST gradient is removed, a weaker AEJ displaces southward and a weaker monsoon flow ensues. Spectral analysis of meridional velocity displays a variance reduction in the 3-8 day band at the 850-hP a level in western and eastern Africa and at the coast. At the 650-hPa level significant changes are not observed at the latitude of the AEJ (15N), however, a decrease in the variance associated with AEW occurs at the southern flank of the jet. A southward displacement of the jet favors a weakening of the baroclinic energy conversions. Barotropic conversions also appear to be weaker when the SST gradient is removed. The present study suggests that orography plays an important role in determining the variability of meridional wind associated with AEW over Eastern Africa at the lower levels. Further, zonal SST gradients over the Atlantic favor intensification of waves when they reach the coast and the maintenance of disturbances across the Ocean. Also, results could suggest that SST gradients support genesis of AEW just off the coast of Africa.
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Self-service technology i restaurangbranschen : Vilka faktorer påverkar attityder till, och tillfredsställelse med, self-service technology i casual dining-restauranger?Linn, Grubbström, Pers, Johannes January 2018 (has links)
Digitaliseringens framväxt har förändrat hur tjänster erbjuds på marknaden. Det blir allt vanligare att kunder interagerar med teknologi i servicemöten istället för med servicepersonal, en teknologi som benämns self-service technology (SST). Tidigare forskare har beskrivit flera övergripande anledningar till att företag väljer att implementera SST, exempelvis; reducerade kostnader, ökad produktivitet, ökad kundnöjdhet och lojalitet samt för att nå nya kundsegment. Tidigare forskning har bedrivits kring vilka faktorer som påverkar attityder till och tillfredsställelse med SST i olika kontexter, vilka visat sig föregå användning av SST. Förekomsten av SST inom casual dining-restauranger är dock en relativt ny företeelse, där forskning kring konsumenters attityder och tillfredsställelse saknas. Restauranger av casual dining-karaktär kan definieras som en typ av restaurang som ligger mellan snabbmatsrestaurang och finrestaurang. Syftet med denna studie är att utvidga den befintliga forskningen inom self-service technology (SST) till casual dining-restauranger. Mer specifikt är syftet att undersöka applicerbarheten av tidigare SST-forskning på en relativt ny och unik restaurangkontext, för att kartlägga vilka faktorer som påverkar konsumenters attityder till och tillfredsställelse med SST i denna kontext. Vidare är syftet att undersöka om det finns betydande skillnader mellan hur faktorerna påverkar attityd respektive tillfredsställelse. Att sammantaget kartlägga detta kan ge praktisk användbar information till chefer för casual dining-restauranger som står inför beslutet att utforma och implementera liknande SSTs i sina verksamheter. Studiens syfte mynnade ut i följande frågeställning: Vilka faktorer påverkar konsumenters attityder till, och tillfredsställelse med, self-service technology i casual dining-restauranger? För att besvara forskningsfrågan genomfördes en fallstudie av restaurangkedjan Pinchos. Totalt 20 hypoteser formulerades kring valda faktorers eventuella påverkan på restaurangbesökares attityd till och tillfredsställelse med SST i casual dining-restauranger. För att undersöka dessa hypoteser genomfördes en kvantitativ undersökning i form av en internetdistribuerad enkät. Totalt 169 respondenter besvarade enkäten. Enkla och multipla linjära regressionsanalyser genomfördes därefter för att analysera empirin. Resultatet visar att faktorerna: användbarhet, enkelhet vid användning, nöje, pålitlighet samt support vid behov uppvisar ett signifikant positivt samband med såväl attityd till som tillfredsställelse med SST i casual dining-restauranger när de studeras enskilt. Studien visar vidare att faktorerna behov av interaktion med personal samt avsaknad av personlig service uppvisar ett signifikant negativt samband med såväl attityd till som tillfredsställelse med SST i denna kontext. Studien visar således att samtliga faktorer påverkar både attityd och tillfredsställelse. Faktorerna ekonomisk kompensation och technology readiness visade inget signifikant samband med varken attityd eller tillfredsställelse när de studerades enskilt. Faktorn kontroll analyserades ej då enkätfrågorna relaterade till denna faktor uppvisade för låg intern konsistens.
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Avaliação da cultura de segurança de uma montadora de veículosMelo, Lucass Nunes de 11 January 2016 (has links)
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Previous issue date: 2016-01-11 / It is essential that the production and the prevention of accidents keep up inseparable in the organizational environment. In this context the safety culture seeks a healthy and safe environment. Thus, we conducted a case study on an automaker through qualitative research and the participation of 43 employees in the interviewing process to verify the safety culture in the worker's perspective. The utterances of these were compared with the safety culture proposed by the International Atomic Energy Agency. The qualitative data analysis was supported by WEBQDA application by the award three units of meaning, and following aspects: institutional, behavioral and relationship in SST. After data analysis, it was possible to infer that in the workers perspective , the organization's safety culture is based on the use of personal protective equipment, the supervision and training for work, seeking the reduction of accidents. We conclude that the company's safety culture is in line with the recommendations by the IAEA, but it is necessary the involvement of senior management on issues related to health and safety.It is also recommended conducting periodic educational campaigns to promote and solidify the safety culture in the company. / É essencial que a produção e a prevenção de acidentes se mantenham indissociáveis no ambiente organizacional. Neste contexto, a cultura de segurança busca um ambiente saudável e seguro. Desse modo, realizamos um estudo de caso em uma montadora de automóveis, por meio da pesquisa qualitativa e da participação de 43 trabalhadores no processo de entrevistas para verificar a cultura de segurança na perspectiva do trabalhador. As verbalizações dos mesmos foram comparadas com a cultura de segurança proposta pelo International Atomic Energy Agency. A análise dos dados qualitativos foi apoiada pelo aplicativo WEBQDA, mediante atribuição de três núcleos de sentido, sendo eles os aspectos: Institucionais, Comportamentais e de Relacionamento em SST. Após análise dos dados, foi possível inferir que, na visão dos trabalhadores, a cultura de segurança da organização está baseada no uso de equipamentos de proteção individual, na fiscalização e na capacitação para o trabalho, buscando a redução de acidentes. Concluímos que a cultura de segurança da empresa está de acordo com o preconizado pelo IAEA, porém, o envolvimento da alta direção em questões ligadas à Saúde e à Segurança se faz necessário, além da aplicação de campanhas educativas periódicas para promover e solidificar a cultura de segurança na empresa.
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Aprimoramento das técnicas observacionais e de calibração do telescópio solar para ondas submilimétricas (SST)Silva, Jorge Fernando Valle 20 September 2016 (has links)
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Previous issue date: 2016-09-20 / Fundação de Amparo a Pesquisa do Estado de São Paulo / Improvements in the calibration of the Solar Sub millimeter-waves Telescope (SST) have
been devised and developed to increase the probability of detection in hard pointing
settings and adverse weather conditions. Fixed the restrictions on the size of the beams,
𝐻𝑃𝐵𝑊 = 4.1′ ± 0.1′ in 212 GHz and 5.5′ × 2.9′ ± 0.1′ in 405 GHz and uncertainties
in the quiet sun brightness temperature (≈ 300K) it was possible to recover the flux
density and the location of a source resulting from a type M solar flare. Using models
of atmospheric solar response to flares, along with a code that calculates emission in the
millimeter and sub-millimeter bands we could set the upper limit size of the emission
region in 30”. Another method devised to evaluate the existence of limb brightening
was applied in azimuth scans to set the limb brightening level in 1.2 ± 0.05 of the mean
central brightness temperature for both frequencies. Finally, the measurement of opacities
in CASLEO shows that the ratio < 𝜏405/𝜏212 > has an upper limit of 5, 51 ± 0.28 Np,
it is still a low value considering the pwv, altitude above sea level, and the geographical
latitude of the place. / Aprimoramentos na calibração do Telescópio Solar para Ondas Submilimétricas (SST)
foram formulados e desenvolvidos para aumentar a probabilidade de detecção em configurações
de apontamento difíceis e condições atmosféricas adversas. Estabelecidas as
restrições no tamanho dos feixes, 𝐻𝑃𝐵𝑊 = 4, 1′ ± 0, 1′ em 212 GHz e 5, 5′ × 2, 9′ ± 0, 1′,
em 405 GHz junto as incertezas na temperatura de brilho de Sol calmo (≈ 300 K) foi
possível aplicar os procedimentos aprimorados de calibração para recuperar a densidade
de fluxo e a localização de uma fonte emissora em 212 GHz que resultam de uma explosão
solar tipo M. Usando modelos de perfil atmosférico de explosões solares, junto com um
código que calcula a emissão nas faixas milimétrica e submilimétrica pudemos estabelecer
que o tamanho limite da região emissora é de 30”. Uma outra metodologia de aprimoramento
desenvolvida para avaliar a existência de abrilhantamento na borda do disco solar
a partir de varreduras em azimute permitiu estabelecer o nível de abrilhantamento em
1, 2±0, 05 vezes a temperatura média central do disco para ambas as frequências. Finalmente,
a medição de opacidades em CASLEO mostra que a relação < 𝜏405/𝜏212 > possui
um limite superior de 5, 51 ± 0, 28 Np, considerado um valor baixo para o conteúdo de
vapor de água, a altitude acima do nível de mar, e a latitude geográfica do lugar.
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Variabilidade climática espectral da temperatura da superfície do mar e sua associação com o clima da América do Sul / Spectral climatic variability of global sea surface temperature and its association with the climate in South AmericaCarlos Batista da Silva 05 September 2017 (has links)
O objetivo deste estudo foi analisar a variabilidade climática espectral da temperatura da superfície do mar, TSM, global associada a oscilações de 1-12 meses, 1-2 anos, 2-4 anos, 4-8 anos e 8-12 anos, entre1854 e 2014, e, as possíveis relações com a variabilidade climática na América do Sul. A análise espectral da TSM foi obtida com a aplicação da técnica de ondeletas a dados mensais. Em termos globais, as bacias tropicais do Pacífico Norte e Sul apresentam os sinais mais intensos da variância de TSM, em todas as faixas espectrais consideradas, e, portanto, valores mais próximos da média global para os trópicos, indicando a importância do oceano Pacífico no clima global. Nesta ordem, as bacias do Pacífico Sul, Pacífico Norte, Atlântico Norte, Indico e Atlântico Sul apresentam valores decrescente de variância da TSM. A análise da tendência linear ao longo do período considerado mostra que, globalmente, fenômenos tropicais com oscilações nas escalas de frequências mais altas, 1-12 meses, 1-2 anos e 2-4 anos, têm apresentado decréscimo de energia e que fenômenos com oscilações nas escalas de frequências mais baixas, 4-8 e 8-12 anos, têm apresentado aumento de energia, o que sugere a troca de energia entre fenômenos de alta e baixa frequência . As oscilações de 2-4 anos e de 4-8 anos na região equatorial do Pacífico são as que apresentam os maiores valores de energia, em especial nas regiões de Ninõ1+2, Niño3, Niño3.4 e Niño4. Os resultados permitem verificar que eventos fortes de El Niño sempre estiveram associados a sinais intensos da variância de TSM nas faixas espectrais de 2-4 anos e 4-8 anos e que os eventos mais fracos de El Niño estiveram associados à faixa de oscilações mais rápidas, 1-2 anos. O início do aumento do valor da variância de TSM para oscilações de 2-4 anos e 4-8 anos na região equatorial do Pacífico apresenta, em todos os casos, antecedência significativa em relação à ocorrência de um evento de El Niño forte, indicando a possibilidade de usar este sinal como preditor da ocorrência de eventos quentes de ENOS. A associação entre a variabilidade da variância espectral de TSM e a variabilidade climática na América do Sul foi verificada com base nos dados precipitação do GPCC, dados de vento das reanálises I e II do NCEP-NCAR e da reanálise do JRA-55. A análise de ondeletas da TSM tropical para a faixa de oscilações de 4-8 anos possibilitou a divisão do período todo em fases distintas: fases positivas, 1948 a 1960 e 1982 a 2003 e fases negativas, 1961 a 1981 e 2004 a 2014. Observou-se que as fases positivas e negativas apresentam um padrão bipolar da precipitação entre as regiões nordeste e sudeste da América do Sul, o que está associado a anomalias contrárias da circulação atmosférica em altos e baixos níveis sobre a região central do continente, constituindo um resultado inédito na área de climatologia. As fases positivas da variância de TSM para oscilações de 4-8 anos estão associadas a anomalias negativas e positivas de precipitação, respectivamente, sobre as regiões nordeste e sudeste da América do Sul enquanto que as fases negativas estão associadas a padrões contrários. O padrão do 4º modo da Análise de Componentes Principais aplicada aos dados de vento em 200 hPa contribui para explicar fisicamente o padrão bipolar da precipitação observado no setor leste do continente na escala decadal, por meio da propagação de ondas de baixa frequência entre o Pacífico Sul e a América do Sul. / The aim of this study is to analyze the global SST spectral climate variability for 1-12 month, 1-2 year, 2-4 year, 4-8 year, and 8-12 year oscillations, in the period from 1854 to 2014, and the possible relations with the climatic variability in South America. The spectral analysis of SST was obtained with the application of the wavelet technique to the monthly data. In global terms, the North and South Pacific basins show the most intense signs of SST variance in all the spectral ranges considered, and therefore, values closer to the global average, indicating the importance of the Pacific Ocean in the global climate. Then, in order of importance, come the basins of the South Pacific, the North Pacific, the North Atlantic, the Indian Ocean and the South Atlantic. The analysis of the linear trend throughout the period considered shows that globally within the tropical range, phenomena with oscillations in the scales of higher frequencies, 1-12 months, 1-2 years, and 2-4 years, have decreased energy and that phenomena with oscillations at lower frequency scales, 4-8 and 8-12 years, have presented increased energy through the course of time, suggesting energy exchange between high frequency phenomena and low frequency phenomena. The 2-4 year and 4-8 year oscillations in the equatorial Pacific region are those with the highest energy values, especially in the Nin1 + 2, Niño3, Niño3.4 and Niño4 regions. It is also possible to verify that strong El Niño events have always been associated with intense SST variance signals in the 2-4 year and 4-8 year spectral bands, and the weaker El Niño events were associated with the 1-2 year spectral bands. The beginning of the increase in the SST variance value for 2-4 year and 4-8 year oscillations in the equatorial region of the Pacific presents, in all cases, significant antecedence in relation to the occurrence of a strong El Niño event, indicating the possibility of using this signal as a predictor of the occurrence of hot ENSO events. The association between SST spectral variance variability and climatic variability in South America was verified based on GPCC precipitation data and wind data from NCEP-NCAR I and II reanalyses and of the JRA-55 reanalysis. The analysis of tropical SST wavelets for the 4-8 year oscillation range allowed the division of the whole period into distinct phases: positive phases, 1948 to 1960 and 1982 to 2003; and negative phases, 1961 to 1981 and 2004 to 2014. It was observed that positive and negative phases present a bipolar precipitation pattern between the Northeast and Southeast regions of the AS, which is associated with anomalies of atmospheric circulation at high and low levels over the central region of the continent, which is an unprecedented result area of climatology. The positive phases of the SST variance for 4-8 year oscillations are associated with negative and positive precipitation anomalies respectively over the northeast and southeast regions of South America while the negative phases are associated with contrary precipitation patterns. The 4th mode pattern of the Principal Component Analysis applied to wind data at 200 hPa contributes to physically explaining the bipolar pattern of precipitation observed in the eastern sector of the continent on the decadal scale by propagating low frequency waves between the South Pacific and South America.
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Fonctionnement dynamique du centre d'upwelling Sud-Sénégalais : approche par la modélisation réaliste et l'analyse d'observations satellite de température de surface de la mer / Dynamics functioning of the Southern Senegal upwelling center : realistic modeling approach and remote sensing SST analysisNdoye, Siny 11 March 2016 (has links)
L’extrémité sud du système du courant des Canaries comprend un centre d’upwelling (résurgence localisée d’eaux froides sous l’action de vents favorables) qui a jusqu’ici reçu peu d’attention. Ma thèse porte sur la dynamique de ce centre d’upwelling sud Sénégal ou SSUC (Southern Senegal Upwelling Center en anglais). Elle s’intéresse donc à la circulation et à la structure thermohaline sur le large plateau sud-sénégalais, entre la côte et _100-200 km au large en se focalisant sur la période d’upwelling (Novembre-Mai). Une des particularités de la zone est la séparation entre la zone d’upwelling au centre du plateau et des eaux plus chaudes au large et à la côte. Mes travaux combinent analyse d’images satellite et d’observations in-situ, avec la réalisation et l’analyse de simulations numériques dans l’état de l’art. Par une analyse fine des conditions physiques de la zone, ils posent la base à une approche intégrée du fonctionnement de l’environnement marin sénégalais. Une première partie des résultats se base sur l’examen et l’analyse de plus de 1500 images satellite de température de surface de la mer SST MODIS, contextualisées par rapport aux conditions synoptiques de vent. Cette analyse met en lumière l’existence d’états récurrents du SSUC, en termes de SST. Elles confirment plus généralement la régularité et la stabilité du fonctionnement dynamique du système, mais aussi révèlent des aspects subtils de la structure de l’upwelling : refroidissement des eaux de surface probablement dû au déferlement et au mélange associé à la marée interne ; interaction complexe entre la remontée locale, le courant de Mauritanie et le jet côtier ; complexité probable des échanges entre les différentes parties du plateau (plateau intérieur accueillant des eaux réchauffées, plateau central où est fréquemment situé la langue d’eau froide). L’amplitude du cycle diurne suggère que de grandes incertitudes restent à lever dans le budget de chaleur de l’upwelling . Les limites des études soulignent la nécessité de continuer la mesure in situ dans le SSUC, en particulier des vents. Le fonctionnement dynamique du SSUC est aussi étudié par la modélisation hydrodynamique (ROMS) à haute résolution (_2km). Différentes simulations ont été réalisées en variant les forçages (climatologiques ou synoptiques pour le vent ; modification fine échelle des flux de chaleur en domaine côtier ; présence ou absence de marée). Les solutions numériques montrent en général un bon accord avec les observations satellite et in situ disponibles. Ces solutions éclairent le fonctionnement dynamique du système notamment en termes de circulation, de position de remontée d’upwelling, mais également du devenir des eaux upwellées grâce à une analyse lagrangienne. Nous avons notamment pu montrer que la zone nord du SSUC est la zone principale de remontée et les eaux qui y remontent, proviennent en grande majorité de la zone sud du SSUC d’où elles sont amenées par le courant de Mauritanie. Les analyses lagrangiennes ont aussi permis de - 3 - révéler la dynamique associée à la zone côtière de nourricerie et de nuancer le schéma conceptuel de rétention précédemment admis. La sensibilité de la dynamique du SSUC aux forçages atmosphériques est modeste avec néanmoins des modulations des échanges cross-shore qui peuvent être importantes pour l’écosystème. / The southern end of the Canary current system comprises of an original upwelling center that has so far received little attention. This Ph.D. Thesis focuses on the dynamical functioning of the Southern Senegal-Gambia Upwelling Center (SSUC). We are interested in the upwelling circulation and thermohaline structure on the shelf between the coastline and 100-200 km offshore. Our focus is on the upwelling period (November to May). The main originality of the SSUC compared to other upwelling centers stems from its continental shelf that is broad and shallow (20–30 m over tens of kilometers). The normal state of the system comprises the classical upwelling front but also a well-defined inner-shelf front that separates cold upwelled waters from nearshore warmer waters. We investigate its dynamical functioning using analysed satellite images, in situ data and state-of-theart 3D numerical simulations. Through a fine-scale analysis of the physical conditions of the SSUC, this work poses the basis of an integrated approach to the Senegalese marine environment functioning. A first part of results is based on the careful examinations and analysis of over 1500 satellite images of sea surface temperature scenes contextualized with respect to wind conditions. Analysis confirm the regularity and stability of the SSUC dynamical functioning (as manifested by the recurrence and persistence of particular SST patterns). The analysis also reveal subtle aspects of its upwelling structure : shelf break cooling of surface waters consistent with internal tide breaking/mixing ; complex interplay between local upwelling and the Mauritanian current off the Cape Verde headland ; complexity of the inner-shelf/mid shelf frontal transition. The amplitude of the diurnal cycle suggests that large uncertainties exist in the SSUC heat budget. The studies limitations underscore the need for continuous in situ measurement in the SSUC, particularly of winds. The dynamical functioning of SSUC is also investigated by means of numerical simulations, using the hydrodynamical Regional Ocean Modeling System ROMS (_x _ 2 km). Different simulations have been carried with varying forcings (climatological or synoptic wind ; fine-scale adjustments of heat flux in coastal area ; presence or absence of tides). Numerical solutions show a good agreement with available satellite and in situ observations . These solutions clarify the dynamical functioning of the system especially in terms of circulation, location of cold water upwelling but also fate of upwelled water through a Lagrangian analysis. We show in particular that the northern part of the SSUC is the main upwelling area. Waters that upwelled in this area predominantly come from the southern of the SSUC, through advection by the Mauritanian current. Lagrangian analysis also revealed the dynamics associated with the coastal area of nursery and nuance the conceptual retention scheme previously admitted. The sensitivity of the dynamics of SSUC to atmospheric forcings is modest with nevertheless some modulations of the cross-shore exchanges that may be important to the ecosystem.
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Srovnání pulsujícího proudění newtonské a ne-newtonské kapaliny v komplexní geometrii / Comparison of Pulsating Flow of Newtonian and non-Newtonian Fluid in Complex GeometryKohút, Jiří January 2020 (has links)
This master's thesis deals with pulsating flow of Newtonian and non-Newtonian fluid. Theoretical part represents necessary theoretical knowledge for pulsating flow and understanding of non-Newtonian behaviour. Furthermore the thesis focus is directed on numerical simulation of pulsating flow in straight, ideally rigid tube and in patient-specific model of human artery, more precisely in carotid. Two methods are used: numerical solution based on finite volume method (FVM) and also analytical solution using Bessel functions by Womersley. Results are validated against experimental measurements of velocity profiles by particle image velocity method (PIV). The agreement between numerical and experimental data with consideration of PIV inaccuracy was was very good from both point of views - qualitative and quantitative. Numerical solution also compare influence of turbulence and non-Newtonian behaviour towards base (laminar flow, Newtonian fluid). Developed methodology is then applied on patient-specific model of carotid, which was renovated from computed tomography. Measurements in vivo in human arteries is very expensive and often invasive. Because of that measurement outputs are limited, most of the time on pressure and flow. Computational fluid dynamics (CFD) is non-invasive and outputs are through whole domain. Due to these advantages CFD significantly contributes to understanding of hemodynamics influence in cardiovascular diseases.
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Between Faith and Bureaucracy : The treatment of immigrants’ religion in Swedish integration policy, 1974 –1986Amanatiadis, Matthaios January 2020 (has links)
This essay contributes new knowledge on Sweden’s immigrant- and integration policy during the years 1974–1986 by researching the policy’s treatment of immigrants’ religion and that of their faith communities. This is achieved through an empirical analysis on how immigrants’ religion was understood, argued for and regulated during key points of policy evaluation, as well as how this was expressed in practice by relevant actors and measures. The analysis focusses on the official government investigations that respectively formulated and evaluated Sweden’s integration policy. It furthermore delves into how immigrant faith communities were institutionally represented and allocated state support by the two state-affiliated organizations associated with these tasks, namely the Swedish Free Church Council (SFR) and its Cooperation Committee for State Support to Faith Communities (SFRS/SST). The essay draws its inspiration and theoretical departure points from theories on secularism, bureaucratization and models of immigrant incorporation, which are operationalized using a ‘What’s the problem represented to be?’ (WPR) methodology. The essay’s empirical findings indicate that religion was initially understood to have reduced cultural and societal significance than ethnicity and language. This understanding gradually changed over time and was amended when Swedish integration policy was evaluated during the 1980s. The empirical analysis furthermore shows that immigrant faith communities received reduced state support in relation to immigrant ethnic organizations, which resulted in administrative and representational dependency on SFR and SST. Following the policy’s evaluation during the 1980s, an initiative to increase state support for faith communities and improve their organizational independence was taken by the Swedish state but had not been implemented by 1986.
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Hydro-morphological Study of Braided River with Permeable Bank Protection Structure / 透過型河岸防護施設を伴う網状河川の水成地形に関する研究Shampa 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21723号 / 工博第4540号 / 新制||工||1708(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 中川 一, 准教授 竹林 洋史, 准教授 川池 健司 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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