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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.
101

Effects of solar heating on the indirect effect of aerosols as deduced from observations of ship tracks /

Christensen, Matthew W. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 47-49). Also available on the World Wide Web.
102

Building energy conservation and the environment in Hong Kong : a case study of glazing wall office building /

Pok, Yuk-fu. January 1998 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 75-80).
103

Structure and energy transport of the solar convection zone

Armstrong, James D., January 2004 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 134-139).
104

Radiation conditions in an Antarctic environment = Strahlungsbedingungen in einer antarktischen Umbegung /

Wuttke, Sigrid. January 2005 (has links) (PDF)
Thesis (doctoral)--Universität Hannover, 2004. / Includes bibliographical references (p. 129-137). Also available in color version in PDF format.
105

Sun rhythm form

January 1981 (has links)
Ralph L. Knowles. / Includes bibliographical references and index.
106

Regiões estáveis para população de partículas e detritos na região externa do sistema de Plutão /

Gallardo, Daniel Martin Gaslac. January 2016 (has links)
Orientador: Silvia Maria Giuliatti Winter / Coorientadora: Pryscilla Maria Pires dos Santos / Banca: Rafael Sfair de Oliveira / Banca: Maria Helena Moreira Morais / Resumo: Os novos dados obtidos do sistema de Plutão, durante sua passagem pelo sistema em julho de 2015, estão sendo enviados pela sonda New Horizons. Plutão possui um conjunto de cinco satélites, Caronte (forma um sistema bin'ario com Plutão), Estige, Nix, Cérberos e Hidra. A recente descoberta desses dois pequenos satélites, Estige e C'erberos, faz com que seja necessário reestudar essa região externa, além da órbita de Caronte. Neste trabalho analisaremos a estabilidade da região externa do sistema Plutão-Caronte para um conjunto de partículas-teste da ordem de centímetros e micrometros sob a influência gravitacional de todos os corpos do sistema de Plutão e da pressão de radiação solar (para partículas de micrometros). Essas partículas estarão inicialmente em órbitas excêntricas e inclinadas; serão assumidos diferentes valores de excentricidade e inclinação. Resultados mostraram que para um conjunto de partículas, originalmente localizadas no plano orbital do sistema de Plutão, 10% colidiram com os corpos maiores e 25% foram ejetadas. Já para o sistema de partículas com órbitas inclinadas (I = 96.2 ◦ ), a maioria dessas partículas são estáveis. Apresentaremos os resultados obtidos para outros valores de inclinação e faremos a comparação com os resultados obtidos para um conjunto de partículas micrométricas da ordem de 1, 5 e 10µm / Abstract: The new data from the Pluto system during its passage through the system in July 2015, are being sent by the spacecraft NewHorizons. Pluto has a set of five satellites, Charon (forms a binary system with Pluto), Styx, Nix, Kerberos, Hydra. The recent discovery of these two small satellites, Styx and Kerberos, makes it necessary to restudy this outer region beyond the orbit of Charon. In this work we analyze the stability of the outer region Pluto-Charon system for a set of particle-test centimeters order and micron under gravitational influence of all bodies Pluto system and solar radiation pressure (for particle microns). These particles are initially eccentric and inclined orbits; They are assumed different eccentricity values and inclination. Results showed that for a set of particles originally located in orbital plane of Pluto system collided with 10% larger bodies and 25% were ejected. As for the particle system with inclined orbits (I = 96.2◦ ), most of these particles are stable. We present the results obtained for other of inclination values and make a comparison with the results obtained for a set of micrometric particles of the order of 1, 5 and 10µm / Mestre
107

Equações de estimativas das irradiações e frações global, difusa e direta infravermelha em Botucatu SP / Brasil /

Rossi, Taiza Juliana, 1987. January 2018 (has links)
Orientador: João Francisco Escobedo / Banca: Alexandre Dal Pai / Banca: Eduardo Nardini Gomes / Resumo: É descrito no trabalho um estudo sobre as irradiações e frações solares global, difusa e direta diárias dos espectros total e infravermelho. A base de dados foi medida no período de 2003 a 2006 em Botucatu/SP/Brasil. Por meio de uma análise estatística, determinou-se os valores médios totais e sazonais das três irradiações em ambos os espectros, enquanto que, em uma análise climática avaliou-se os efeitos da nebulosidade, vapor de água e aerossóis na sazonalidade das irradiações. Foram propostas equações de regressão linear (tipo Y= a×X),obtidas para estimativas das irradiações global (HGNIR), difusa (HdNIR) e direta(HDNIR) do espectro infravermelho em função das irradiações global (HG), difusa (Hd) e direta (HD) do espectro total, sob todas as condições de céu. Os coeficientes de determinação (R2) próximos de 1 mostram que as irradiações dos espectros total e NIR estão bem correlacionadas estatisticamente. Os coeficientes angulares quantificam os valores das frações infravermelhas incidentes como sendo: KGNIR= (HGNIR / HG) = 46,1%; KdNIR = (HdNIR / Hd) = 38,2% e KDNIR = (HDNIR / HD) = 51,1%. Os indicativos estatísticos na validação: MBE inferior a 5%; RMSE iguais a 5,6%, 20,4% e 9,2% e valores d de Willmott superiores 0,98 respectivamente, indicam exatidão, precisão e elevada concordância no ajuste entre a estimativa e a medida, para as três equações. Em relação aos valores das frações anuais, a análise sazonal das equações de estimativas mostra que o valor de KGNIR é menor ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study describes global, diffuse and direct solar irradiation and fractions of the total and infrared spectra (NIR). The database was obtained in the period from 2003 to 2006 in Botucatu / SP / Brazil. Through statistical analyses, values of the three total and seasonal average irradiations in both spectra were determined, while a climate analysis evaluated the effects of cloudiness, water vapor and aerosols on the seasonality of the irradiations. Linear regression equations (y = a × X) were proposed to estimate global (HGNIR), diffuse (HdNIR) and direct (HDNIR) irradiations of the infrared spectrum as a function of the global (HG), diffuse (Hd) and direct (HD) irradiations of the total spectrum in all sky cover conditions. Determination coefficients (R2) close to 1 show that the irradiations of the global and NIR spectra are statistically well correlated. The angular coefficients quantify the values of incident infrared fractions as: KGNIR = (HGNIR / HG) = 46.1%; KdNIR = (HdNIR / Hd) = 38.2% and K DNIR = (HDNIR / HD) = 51.1%. Statistical indicators in the validation: MBE less than 4.6%; RMSE equal to 4.3%, 17.8% and 7.3% and Willmott's d values higher than 0.978, respectively, indicate precision, accuracy and high agreement on the adjustment between estimated and measured values for the three equations. In relation to values of the annual fractions, the seasonal analysis of the estimate equations shows that the KGNIR value is lower in the summer (44.8%) and spring (45.1%) and higher in the autumn (47.6%) and winter (48.0%); KdNIR value is the same in the summer (38.2%) and higher in the spring (40.1%) and lower in the autumn (34.9%) and winter (33.9%); KDNIR value is lower in the summer (49.0%) and spring (49.3%) and higher in the autumn (52.7%) and winter (53.9%). The analysis of the estimate equations considering sky covers shows that KGNIR value is lower in cloudy sky (I), partially ... / Mestre
108

Investigating the effects of dietary-derived and sunlight-derived vitamin D3 on markers of immune function

Maboshe, Wakunyambo January 2018 (has links)
Primarily synthesised via cutaneous exposure to solar ultraviolet B (UVB) radiation, serum vitamin D concentrations, measured as 25-hydroxyvitamin D (25(OH)D), fluctuate according to solar availability. Seasonal variations in vitamin D are common in areas of high or low latitude determined by the distance from the sun. Seasonal variations in blood pressure, immune markers and some diseases including influenza, have also been reported. However, the contributions of UVB light or vitamin D on the immune markers have not been fully determined. Against this background, the purpose of this research was to investigate the effects of UVB light therapy and dietary vitamin D supplementation on markers of immune function. The D SIRe1 study aimed to assess whether dietary-derived 25(OH)D could have similar effects on immune function as light-derived 25(OH)D. The study was an 8-week comparative intervention trial in healthy adults randomised to receive either 3 times weekly UVB radiation (equivalent to doses received during a Grampian-summer) for 4 weeks; or oral vitamin D3 (1000 IU a day for 8 weeks). Total 25(OH)D was measured by dual tandem mass spectrometry of serum samples following removal of protein and de-lipidation, whilst regulatory T cells (Tregs), known for maintaining immune system homeostasis, by flow cytometry. The study showed similar short-term effects between oral vitamin D and UVB exposure on measured outcomes. However, study interpretation was limited by the lack of a placebo group, yet, to our knowledge, this was the first study to directly compare dose-matched UVB therapy and vitamin D supplementation in healthy participants. Using similar laboratory techniques, the D-SIRe2 study, a placebo-controlled trial, assessed short-term (12 weeks) and long-term (43 weeks) effects of vitamin D supplementation on immune markers. Commencing in spring (March) and finishing in winter (January) 2015/2016, the study showed seasonal fluctuations in most immune markers. The fluctuations did not change according to variations in 25(OH)D concentrations nor were they correlated with solar UVB doses, with the exception of T cell proliferative responses, which were positively correlated with daily solar UVB doses. An interesting finding from this study was the prevention of increases in pro-inflammatory IFN-γ cytokine concentrations in the spring and summer time in the vitamin D3 supplemental group versus placebo. IFN-γ concentrations were raised from 7940 pg/mL at baseline in March, to roughly 12400 pg/mL at week 4 and to 13909 pg/mL at week 12 in the placebo group. The concentrations were roughly 1.3 times the mean concentrations measured in the vitamin D group at the timepoints following baseline concentrations of 10678 pg/mL, and 10013 pg/mL and 10233 pg/mL at weeks 4 and 12, respectively. The interactions between solar light or seasonal effects and oral vitamin D supplementation, as well as their individual and combined effects on immune function, are yet to be fully determined. Moreover, the metabolic and physiological implications of seasonal variation in serum 25(OH)D concentration and markers of immune function are currently unknown, requiring further investigation.
109

Ação de forças gravitacionais e não gravitacionais sobre o movimento orbital de satélites artificiais

Carvalho, Jean Paulo dos Santos [UNESP] 04 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04Bitstream added on 2014-06-13T19:12:15Z : No. of bitstreams: 1 carvalho_jps_me_guara.pdf: 1120789 bytes, checksum: 42d7f707a41ef83886b116f000a33c22 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Uma teoria para estudar o movimento orbital de satélites artificiais sobre efeitos do arrasto atmosférico e da pressão de radiação solar direta - considerando a sombra da Terrae alguns termos do geopotencial - é desenvolvida analiticamente. A sombra daTerra é modelada utilizando a função sombra, como introduzida por ferraz Mello: igual zero quando o satélite está na região de sombra e igual um quando é iluminado pelo sol. As componentes do arrasto são dadas por Vilhena de Moraes baseado no modelo atmosférico TD-88. O método de Hori para sistemas não canônicos é aplicado para resolver as equações de movimento. Um software para manipulação algébrica é fundamental apra fazer os cálculos necessários. Efeitos seculares e periódicos que influenciam no movimento orbital dos satélites artificiais são analisados. Expressões analíticas são apresentada explicitamente para os principais termos seculares nas variações dos elementos orbitais. É dada ênfase aos termos de acoplamento que surgem na solução do sistema de equações diferenciais. Utilizando dados orbitais do satélite CBERS-1 um estudo é feito para analisar ordens da variação do semi-eixo maior devidas as pertubações consideradas. / A theory to study the orbital motion of artificial satellites under the effects of the atmospheric drag and of the direct solar radiatin pressure - considering the Earh's shadow and some terms of the geopotential - is developed analytically. The Earth shadow is modeled using the shadow function introduced by Ferrz Mello: equal zero when the satellite is in the shadow region and equal one when it is illuminated by the Sun. The drag components are given by Vilhena of Moraes based in the TD-88 temospheric model. The Hori's method for non-canonical systems is applied to solve the motion equation. A algebric manipulator software is fundamental to do the necessary calculations. Secular and periodic effects on the orbital motion of artificial satellites are analyzed. Analytic expressions are presented explicity for the main secular terms of the variations of the orbital elements. Emphasis is given to the coupling terms that appear in the solution of the differential euqatin systems. Using orbital data of the satellite CBERS-1 a study is done to analyze the order of magnitude of the variation of the semi-major axis due to the considered pertubation.
110

Estimativa da irradiação total sobre uma superfície inclinada a partir da irradiação global na horizontal

Scolar, José [UNESP] 02 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-02Bitstream added on 2014-06-13T19:02:04Z : No. of bitstreams: 1 scolar_j_dr_botfca.pdf: 1328254 bytes, checksum: ee3f5f1ff4f7b0c84f4f5bffe942ecb7 (MD5) / Neste trabalho, realizou-se um estudo de modelagem da irradiação total que incide sobre uma superfície inclinada, com face voltada para o Equador, e com inclinação de 22,85º, igual a da latitude local. Foram testados 7 modelos, existentes na literatura, utilizando partição diária de energia. Os modelos de Temps & Coulson, Klucher e circunsolar, apresentam os piores desempenhos e não devem ser utilizados na estimativa da irradiação total diária em Botucatu, por outro lado os modelos de Liu & Jordan, Hay, Perez et al. e Reindl et al., são similares entre si, e apresentam boa concordância quando comparados com os dados observacionais, sendo o modelo de Hay ligeiramente superior aos outros. O propósito deste trabalho é obter um modelo que utilize somente a irradiação global medida na superfície horizontal para estimar a irradiação total na superfície inclinada. Para tanto, os modelos de estimativa foram modificados de duas maneiras diferentes. Na primeira, a irradiação difusa foi estimada em função da irradiação global, através do ajuste empírico utilizando a técnica de regressão linear, na forma Kd = f (Kt) , fração da difusa contida na global (Kd ), com o índice de claridade (Kt ), nesse caso, o melhor ajuste é dado por um polinômio de 4º grau Kd = 0,993 + 0,178Kt - 0,945Kt2 - 4,712Kt3 + 4,891Kt4 . Na Segunda modificação, a irradiação direta KBH , fração da irradiação direta contida na irradiação global, foi ajustada através da técnica de regressão linear, em função do índice de claridade, na forma KBH = f (Kt ) , nesse caso o melhor ajuste foi linear, obtido para intervalos específicos de Kt , KBH = 0 para Kt £ 0,25 , e KBH = -0,386 +1,572Kt para Kt >0,25. Os resultados obtidos com essas modificações mostram que os modelos têm melhores... / A modelling study of the total irradiation reaching a tilted surface facing towards the equator at tilt same of local latitude of 22,85º,, is presented. In this study seven total irradiation incident on a tilted surface estimate models were tested and compared among them, using the daily partitioning energy. Temps & Coulson, Klucher and circumsolar models showed very poor results, and it is suggested that they should not be used to estimate the daily total irradiation for the Botucatu region. On the other hand the Liu & Jordan, Hay, Perez et al. and Reindl et al. models have shown similar performance and presented a good agreement with the observational data. The Hay model however produced better irradiation estimates. The aim of this study is examine and improved irradiation estimative model for tilted surface knowing only the global irradiation measured at horizontal surface. In order to achieve this, two modifications were made on those models mentioned above. The first modification consisted to apply empirical functions to determine the diffuse irradiation by the global radiation measurements. These empirical functions were tuned using the regression linear thecnique, the fraction of the diffuse irradiation (Kd ) from the global irradiation, was correlationed with the clearness index (Kt ). In this case the highest correlation found was, Kd = 0,993 + 0,178Kt - 0,945Kt2 - 4,712Kt3 + 4,891Kt4 a fourth order polynomial function. In the second modification the fraction of the direct irradiation KBH from the global irradiation was correlationed assuming a linear correlation at given intervals of Kt : KBH = 0 for Kt £ 0,25 , and KBH = -0,386 + 1,572Kt for Kt >0,25 otherwise. Model results showed the empirical relationship KBH = f (Kt ) , present better results and the Hay model presented a better performance compared with others models for the... (Complete abstract, click electronic address below)

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