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Interactive visualization of space weather dataTörnros, Martin January 2013 (has links)
This work serves to present the background, approach, and selected results for the initial master thesis and prototyping phase of Open Space, a joint visualization software development project by National Aeronautics and Space Administration (NASA), Linköping University (LiU) and the American Museum of Natural History (AMNH). The thesis report provides a theoretical introduction to heliophysics, modeling of space weather events, volumetric rendering, and an understanding of how these relate in the bigger scope of Open Space. A set of visualization tools that are currently used at NASA and AMNH are presented and discussed. These tools are used to visualize global heliosphere models, both for scientific studies and for public presentations, and are mainly making use of geometric rendering techniques. The paper will, in detail, describe a new approach to visualize the science models with volumetric rendering to better represent the volumetric structure of the data. Custom processors have been developed for the open source volumetric rendering engine Voreen, to load and visualize science models provided by the Community Coordinated Modeling Center (CCMC) at NASA Goddard Space Flight Center (GSFC). Selected parts of the code are presented by C++ code examples. To best represent models that are defined in non-Cartesian space, a new approach to volumetric rendering is presented and discussed. Compared to the traditional approach of transforming such models to Cartesian space, this new approach performs no such model transformations, and thus minimizes the amount of empty voxels and introduces less interpolation artifacts. Final results are presented as rendered images and are discussed from a scientific visualization perspective, taking into account the physics representation, potential rendering artifacts, and the rendering performance.
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Modélisation de l'irradiance solaire spectrale dans le proche et moyen ultravioletBolduc, Cassandra 04 1900 (has links)
Nous présentons un modèle pour l’irradiance solaire spectrale entre 200 et 400 nm. Celui-ci est une extension d’un modèle d’irradiance solaire totale basé sur la simulation de la fragmentation et l’érosion des taches qui utilise, en entrée, les positions et aires des taches observées pour chaque pas de temps d’une journée. L’émergence des taches sur la face du Soleil opposée à la Terre est simulée par une injection stochastique. Le modèle simule ensuite leur désintégration, qui produit des taches plus petites et des facules. Par la suite, l’irradiance est calculée en sommant la contribution des taches, des facules et du Soleil inactif. Les paramètres libres du modèle sont ajustés en comparant les séquences temporelles produites avec les données provenant de divers satellites s’étalant sur trois cycles d’activité. Le modèle d’irradiance spectrale, quant à lui, a été obtenu en modifiant le calcul de la contribution des taches et des facules, ainsi que celle du Soleil inactif, afin de tenir compte de leur dépendance spectrale. Le flux de la photosphère inactive est interpolé sur un spectre synthétique non magnétisé, alors que le contraste des taches est obtenu en calculant le rapport du flux provenant d’un spectre synthétique représentatif des taches et de celui provenant du spectre représentatif du Soleil inactif. Le contraste des facules est quand à lui calculé avec une procédure simple d’inversion de corps noir. Cette dernière nécessite l’utilisation d’un profil de température des facules obtenu à l’aide de modèles d’atmosphère. Les données produites avec le modèle d’irradiance spectrale sont comparées aux observations de SOLSTICE sur UARS. L’accord étant peu satisfaisant, particulièrement concernant le niveau d’irradiance minimal ainsi que l’amplitude des variations, des corrections sont appliquées sur le flux du Soleil inactif, sur le profil de température des facules, ainsi qu’à la dépendance centre-bord du contraste des facules. Enfin, un profil de température des facules est reconstruit empiriquement en maximisant l’accord avec les observations grâce à un algorithme génétique. Il est utilisé afin de reconstruire les séquences temporelles d’irradiance jusqu’en 1874 à des longueurs d’ondes d’intérêt pour la chimie et la dynamique stratosphérique. / We present a model for spectral solar irradiance between 200 and 400 nm. It is an extension of a model for total solar irradiance based on sunspots fragmentation and erosion. This model takes the observed sunspot position and area as input for every oneday time step whereas emergences on the far side of the Sun are injected stochastically. The model simulates the spot’s disintegration and fragmentation into smaller structures such as spots and faculae and produces a magnetic structures area distribution evolving with time. The model contains many free parameters controlling the spots fragmentation, the quiet Sun irradiance, etc. They are adjusted by comparing the model outputs with observations from satellites spanning approximately three activity cycles. The model for spectral irradiance is a modified version of the model for total irradiance. More precisely, the spots and faculae contrast calculation and the quiet Sun contribution are adjusted to account for their spectral dependance. First, the quiet Sun flux is interpolated on a non magnetic synthetic spectrum, while the spots contrast is calculated with the ratio of the flux from a synthetic spectrum colder than the non magnetic photosphere, and the flux from a quiet Sun spectrum. The facular brightening is calculated with a simple procedure using the black body theory. This procedure interpolates a temperature associated with the formation height of photons from faculae on a temperature profile resulting from model atmosphere calculations. The spectral irradiance time series calculated with the model are compared to data from SOLSTICE on UARS. The two data sets do not agree very well, especially when we consider the minimum irradiance level and the amplitude variations over a complete cycle. Therefore, we apply a correction on the quiet Sun level and on the facular temperature profile. Finally, using a genetic algorithm, we reconstruct an empirical facular temperature profile by maximizing the fitness with observations. We use it to reconstruct spectral irradiance time series starting in 1874 at wavelengths of interest for stratospheric chemistry and dynamics.
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Chinese Nation-building And Sun Yat-senErgenc, Ceren 01 August 2005 (has links) (PDF)
The intellectual and political roots of present-day China lie in the late imperial era and the transition to modern statehood. As the last chain of the thousands years of dynastic rule in China, the Qing Dynasty ended in 1911 with a revolution. Even though the Republican regime was immediately established after their revolution, it took three decades until thenew government (People&rsquo / s Republic of China) achieved full sovereignty on the territory.
The thesis argues that the 1911 Revolution is a major turning point in Chinese transformation not only because of the regime change but also the ideological shift towards modern statehood. In this study, first, the social forces and actors on the eve of the Revolution are analyzed. The gentry-domination of society and the power relations within the forces involved in the Revolution - especially the intellectuals and the military - appear to be the two major reasons why the transition was not completed with the Revolution. The second focus of the study: the process of breaking with the past. In other words, how was the shift in people&rsquo / s mind achieved? In China, this turning point did not coincide with the 1911 Revolution and/or regime change. It came later in 1910s, reaching its peak in 1919, with the New Culture Movement of the May Fourth intellectuals. There had been some influential intellectuals building a nationalist discourse even before the May Fourth Movement (e.g. Liang Qichao, reformist and ideologue in late Qing dynasty) but the radical and outspoken tone of the New Culture Movement achieved the grounds for a shift in minds. I will briefly analyze the intellectual work of the period and its politicization. A special emphasis is given on Sun Yat-sen&rsquo / s political and intellectual contribution to the transition since he was not only a major political activist but also a theoretician whose works (Three Principles of People) have been influential on China&rsquo / s nation-building process.
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Density and design : high density private residential development in Hong Kong (TaiKoo Shing and Mei Foo Sun Chuen) /Chan, Kit-chu, Winky. January 1993 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1993. / "Workshop report." Includes bibliographical references.
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Κατασκευή μικροϋπολογιστικού συστήματος για τη βελτίωση της απόδοσης φωτοβολταϊκής συστοιχίαςΚαρύδα, Άρτεμις-Νεκταρία 11 January 2011 (has links)
Η παρούσα διπλωματική εργασία πραγματεύεται τη μελέτη και κατασκευή μιας διάταξης που παρακολουθεί συνεχώς τη θέση του ήλιου στον ουρανό και στρέφει αντίστοιχα ένα φωτοβολταϊκό πάνελ κατά τέτοιο τρόπο ώστε να μεγιστοποιείται η ένταση της ηλιακής ακτινοβολίας που προσπίπτει σε αυτό και επομένως και η ενεργειακή του απόδοση (solar tracker).
Προκειμένου να πραγματοποιηθεί η εφαρμογή, το ίδιο το φωτοβολταϊκό πάνελ χρησιμοποιήθηκε ως ανιχνευτής της θέσης του ήλιου στον ουρανό απλουστεύοντας έτσι την κατασκευή και μειώνοντας το κόστος της καθώς δεν χρειάστηκαν επιπλέον αισθητήρες. Συγκεκριμένα, ανά τακτά χρονικά διαστήματα δειγματοληπτούνταν η τιμή της τάσης στα άκρα του φωτοβολταϊκού πάνελ από τον μικροελεγκτή msp430F169 της εταιρείας texas instruments, αποθηκεύονταν στους καταχωρητές του και αφού μετατρεπόταν το σήμα από αναλογικό σε ψηφιακό συγκρινόταν με τις προηγούμενες τιμές. Ανάλογα με το αποτέλεσμα της σύγκρισης, ο μικροελεγκτής έδινε εντολή στον κινητήρα που κατεύθυνε το φωτοβολταϊκό πάνελ να κινηθεί στην αντίστοιχη κατεύθυνση. Η διαδικασία επαναλαμβανόταν μέχρις ότου βρεθεί το σημείο εκείνο όπου η τάση στα άκρα του γίνεται μέγιστη. Το σύστημα που κατασκευάσαμε περιλαμβάνει κίνηση γύρω από έναν άξονα. Συγκεκριμένα παρακολουθεί την αζιμουθιακή κίνηση του ήλιου ξεκινώντας από την ανατολή (Earth) και καταλήγοντας στη δύση (West). / The present thesis deals with the study and construction of a solar tracker that constantly detects the sun position to the sky and directs correspondingly a photovoltaic panel in order to maximize the intensity of solar radiation prostrating to it and as a result, its energy performance as well.
In order the application to be realized, the same photovoltaic panel was used as detector of the sun position to the sky, simplifying the construction and reducing its cost, as no further sensors were required. Particularly, the point-to-point voltage value of the photovoltaic panel was regularly sampled by the microcontroller msp430F169 of the Texas Instruments Company, it was saved to the register, and after the signal was being converted from analog to digital, it was being compared to the previous value. Depending on the result of the comparison, the microcontroller ordered the motor directing the photovoltaic panel to move across the corresponding direction. The process was being repeated until a point was found were the point-to-point voltage value was the maximum. The system created includes motion around one axis. Particularly, it observes the azimuthal solar motion starting from East and ending to West
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Processamento da carne-de-sol com carne maturada: qualidade sensorial e textura / Processing of matured sun meat: Sensory Quality and TextureSalvino, Alanne Tamize de Medeiros 27 May 2011 (has links)
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Previous issue date: 2011-05-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Sun meat is a widely accepted foodstuff in the Brazilian northeast, with processing generally carried out by hand by small producers who, due to the absence of specific legislation, show differences in their acquisition processes, which influences the final quality with considerable variation in its physical-chemical, microbiological and sensory aspects. This study aimed to characterize the sun meat processing commercialized in the municipality of João Pessoa/PB through structured interviews with shopkeepers and producers and to evaluate the physical-chemical, microbiological and sensory characteristics of sun meat processed with previously matured raw material compared to sun meat commercialized in the municipality of João Pessoa/PB. Three sun meat samples were evaluated, with two being processed at pilot scale, differentiated by the previous treatment of the raw material, one being traditional and the other having matured previously during 14 days. The samples were processed using the commercial cut inside round (m. semimenbranosus e m. adductor femoris), following the processing stages (preparation of the raw material, salting, washing, drying and refrigeration) in accordance with the survey carried out among the producers of the city of João Pessoa/PB. The processed samples were compared with a commercial sample from the city of João Pessoa/PB, which were evaluated in relation to its physical-chemical quality: composition, centesimal composition, chlorates, water activity (Aa), pH, water retention capacity (CRA), color (L*, a*, b*) and shear force with a Warner-Bratzler blade, microbiological analysis (total coliforms and thermotolerant bacteria, Salmonella sp e Estafilococos coagulase positiva) and sensory analysis, by trained panelists, and, acceptance by potential consumers. 79 shopkeepers were interviewed in 15 visited establishments of which, 31,6% process their own sun meat they commercialize, and the slaughterhouses operation was checked (39,2%) regarding the supply of sun meat commercialized in these establishments. A similarity in the processing techniques of processed sun meat was observed for both small producers and slaughterhouses, however, a lack of standardization of operations was found in relation to the type and salting time and the way in which drying was realized in the sun meat processing. The maturing process did not influence the physical-chemical, nor the microbiological quality of the sun meat, not being different from the traditional, nor the commercial sun meat. However, the addition of sodium chlorate and the salting time of the present study were sufficient to reduce the humidity and to increase the chlorate concentrations of the products, but these variations were not sufficient to reduce the Aa, no difference was observed (p≥ 0,05) between the raw material and the products. However, low content of chlorates between 2,49 and 4,66, elevated. Aa between 0,94 and 0,95 and pH between 5,8 and 6,1 show the high perishability of the product, which should have double attention for the use of good practices during its processing, using matured raw material. The maturing process also did not influence the sensory quality of the sun meat, not having any difference (p≥ 0,05), according to both the trained panelists and the acceptance test, where the three samples obtained an acceptance rate of over 60%. The maturing process did not produce the expected effects. Therefore, further study with longer maturing times, and, or, new techniques with the intent of providing even greater tenderness of the sun meat, is recommended. / A carne-de-sol é um alimento de ampla aceitação no Nordeste brasileiro, com processamento, na grande maioria, realizado artesanalmente por pequenos produtores que devido à ausência de legislação específica, apresentam variações no seu processo de obtenção, influenciando na sua qualidade final. Objetivou-se neste trabalho caracterizar o processamento da carne-de-sol comercializada no município de João Pessoa/PB, por meio de entrevista estruturada junto aos comerciantes e produtores, e avaliar as características físico-químicas, microbiológicas e sensoriais da carne-de-sol processada com matéria-prima previamente maturada comparada com carne-de-sol comercial do município de João Pessoa/PB. Foram avaliadas três amostras de carne-de-sol, sendo duas processadas em escala piloto, diferenciadas pelo tratamento prévio da matéria-prima, sendo uma tradicional e a outra previamente maturada por 14 dias. As amostras foram processadas usando o corte comercial coxão mole (m. semimenbranosus e m. adductor femoris), seguindo as etapas de processamento (preparação da matéria-prima, salga, lavagem, secagem e refrigeração) de acordo com o levantamento realizado junto aos produtores da cidade de João Pessoa/PB. As amostras processadas foram comparadas com uma amostra comercial da cidade de João Pessoa/PB, que foram avaliadas quanto à qualidade físico-química: composição centesimal, cloretos, atividade de água (Aa), pH, capacidade de retenção de água (CRA), cor (L*, a*, b*) e força de cisalhamento; análise microbiológica (coliformes totais e termotolerantes, Salmonella sp e Estafilococos coagulase positiva) e análise sensorial, por provadores treinados e, aceitação por potenciais consumidores.Verificou-se que 31,6% dos comerciantes processam a própria carne-de-sol que comercializam; 16,5% são provenientes de pequenos produtores e 39,2% de frigoríficos. Não foram observadas variações nas técnicas de processamento entre os pequenos produtores e os frigoríficos, no entanto, verificou-se a falta de padronização entre as operações em relação ao tipo e tempo de salga e a forma de secagem realizada no processamento das carnes-de-sol. O processo de maturação não influenciou na qualidade físico-química e microbiológica da carne-de-sol, não diferenciando da carne-de-sol tradicional, nem da comercial. A adição de cloreto de sódio e o tempo de salga do presente estudo foram suficientes para reduzir a umidade e aumentar as concentrações de cloretos dos produtos, porém, estas variações não foram suficientes para reduzir a Aa, não sendo observada diferença (p ≥ 0,05) entre as matérias-primas e os produtos. O processo de maturação também não influenciou na qualidade sensorial da carne-de-sol, não havendo diferença (p ≥ 0,05) tanto pelo painel treinado quanto pelo teste de aceitação, onde as três amostras obtiveram aceitação superior a 60%. O processo de maturação não surtiu o efeito esperado, recomendando-se novos estudos com maior tempo de maturação e, ou, novas técnicas com o intuito de proporcionar uma maior maciez da carne-de-sol.
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Interrogating gender constructions in the Daily Sun: an analysis of the coverage of the 'Charter for a Man' campaign against gender violence between November and December 2007Dewa, Nonhlanhla January 2009 (has links)
The study seeks to interrogate the gender constructions in the Daily Sun’s “Charter for a Man” campaign which ran from 7 November to 7 December 2007. It coincided with the 16 Days of Activism against gender violence and was designed to lobby support for this campaign and discourage men from physically abusing women. The “Charter for a Man” listed nine principles that signatories were to abide by. It included a section to be signed by men to be submitted to and collected by the Daily Sun. The campaign was constructed as an intervention into the issue of gender violence. Consequently, the 30 news stories, four editorial pieces and 11 letters to the editor that were published during the campaign period make up the textual data analysed in the study. The news stories consisted of testimonies from abused women and some women abusers. In addition, celebrity signatories were selected to endorse the campaign and encourage other men to follow suit. In the editorials, the campaign was consistently flagged as a nation building initiative which all men were supposed to support. The letters to the editor consisted of readers who either supported or rejected the campaign. The study takes place against the context of a patriarchal society characterised by high levels of violence. Given this scenario, the study is informed by a concern with gender justice and therefore considers whether such a campaign, ostensibly aimed at eradicating gender violence, has the potential of being transformative of gender inequalities. The study set out to establish the kinds of masculinities and femininities that were variously constituted in the campaign as well as the gender discourses that were privileged. It is informed by the theories of feminist poststructuralism and Foucault’s conceptualisation of discourse. As the campaign is the initiative of a tabloid newspaper, it is also considered within the framework of newspaper campaigns and arguments about tabloids and the public sphere. As text based research, the study employs critical discourse analysis as a qualitative procedure of textual analysis. It makes use of an eclectic approach to textual analysis that draws on linguistics, narrative and argumentation. The texts are analysed according to the categories of news texts contained which includes the Charter itself, signatory articles, testimonies, vox pops and letters to the editor. The overarching theme of nationhood projected in the editorials and other categories is also discussed as part of the analysis. The study concludes that the Daily Sun campaign might be a seemingly progressive action at first glance. However, it does not challenge the existing gender order but rather maintains and sustains patriarchal attitudes through the repeated representation of women as weak and in need of patronage and men as their protectors and providers. In some instances, women are constructed primarily as sexual beings as their physical attributes are emphasised, while men are constructed as working class citizens and rational beings. The study therefore proposes that the Daily Sun fails as an alternative public sphere that might make visible the concerns of women as a marginalised group in society. The campaign, it is argued, is self-serving in its promotion of the Daily Sun’s image as the “People’s Paper” rather than serious concerns about gender violence.
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Estudo das atitudes e práticas face à exposição solar dos carteiros do município de Juazeiro do Norte-CE / Study of attitudes and practices to solar exposition of Juazeiro do Norte mailmenOliveira, Séphora Natércia Albuquerque [UNIFESP] 25 August 2010 (has links) (PDF)
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Previous issue date: 2010-08-25 / As relações entre Trabalho e Saúde neste estudo tiveram por base possíveis agravos originados de exposições prolongadas e repetidas ao sol sem a devida proteção. Objetivou-se analisar as atitudes e práticas face à exposição solar dos carteiros do Município de Juazeiro do Norte-CE, identificando quais os recursos e como são utilizados por eles para se protegerem da ação nociva do sol. Objetivou- se também identificar a existência de iniciativa por parte da Empresa de Correios e Telégrafos no sentido de fornecer aos trabalhadores a adoção de recursos para fotoproteção. Tratou-se de um estudo de corte transversal, com abordagem quantitativa. O estudo foi realizado na Empresa de Correios e Telégrafos da cidade de Juazeiro do Norte- CE, envolvendo 25 carteiros, sendo 23 homens e 2 mulheres, com média de idade 35,84 anos. A coleta dos dados foi realizada por meio de um questionário contemplando variáveis de caracterização do grupo, conhecimento sobre os efeitos nocivos dos RUVs, práticas de exposição solar e medidas preventivas relevantes à fotoexposição. Para análise estatística, foi utilizado o programa Statistical Package for the Social Sciences (SPSS) versão 13.0 e realizou- se uma análise descritiva.Dos carteiros pesquisados a maioria foi do sexo masculino (92%) e a média da idade foi de 35,84 anos e todos tinham um bom nível de escolaridade. Em relação ao tempo de vinculo empregatício, a maioria dos carteiros tem mais de 9 anos de trabalho. Quanto ao horário de trabalho externo, todos os carteiros o realizam a partir das 11h00min e retornam a sede dos correios entre às 16h00min e 18h00min. Em relação ao fototipo cutâneo, 56% dos carteiros enquadram- se no fototipo III e o restante distribui- se entre os II, IV e V.Em relação ao fator de proteção 22 carteiros utilizam o fator 30. Quanto ao fornecimento dos correios do filtro solar, 56% responderam que ocorre semanalmente, independentemente de estar faltando ou não o produto.Pode-se concluir que a maioria dos carteiros utiliza meios para proteção solar, no entanto não realizam esta proteção da forma mais adequada. Quanto aos Correios, identificamos que a instituição contribui parcialmente no sentido de fornecer aos trabalhadores investigados recursos para fotoproteção. / The relations between Work and Health in this study have been based on likely damages from long, repeated exposition to the sun without the necessary protection. It has been aimed to analyze the attitudes and practices to solar exposition of Juazeiro do Norte mailmen, we have identified what resources and how they are used by the mailmen in order to protect them from the sun’s harmful rays. It has also been aimed to identify the existence of initiative from the Brazilian Post Company in Juazeiro do Norte city, there are 25 mailmen involved all in all, they are 23 men and 2 women and their age is 34. 84 at average. The data collect has been made through a questionnaire covering variables of group characterization, knowledge about harmful effects of UVRs practices of solar expositions and preventive steps relevant to photo exposure. For statistics analyses, the Statical Package for the Social Sciences program was used (SSPS) 13.0 version and a descriptive analysis. Among the post officers surveyed, most of them are male (92%) and the age average has been 35.85 years and all had a good education level. When it comes to time of employing link, most of post officers have worked for over nine years. In relation to working time, most post officers work from 11:00 am and they get back to the headquarters at about 4:00 pm to 6:00 pm. In relation to cutaneous photo type, 56% post officers fit in photo type III and the rest in II, IV and V groups. In relation to protection factor, 22 post officers utilize factor 30. In relation to the supply of sun screen, 56% answered that it happens every week, independently to lack or not the product. In conclusion, every post man uses some kind of sun protection, nevertheless, they do not do this protection correctly. In relation to the Post Office, we have observed that the company contributes partly in order to supply its investigated clerks resources to protection. / TEDE
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Ensino de física solar em um espaço não formal de educação / Teaching solar physics in an informal educational spaceSilvia Calbo Aroca 13 February 2009 (has links)
Planetários e observatórios oferecem a possibilidade de desenvolver um ensino contextualizado de Astronomia, permitindo a realização de atividades educativas que proporcionam acesso a uma ciência escolar mais autêntica. Com isso em vista, esta pesquisa consistiu no desenvolvimento, aplicação e análise de minicursos sobre o Sol, para o ensino fundamental e física solar, para o ensino médio em um espaço não formal de educação, o Observatório Astronômico do CDCC/USP. Tópicos como a composição química, temperatura e evolução estelar foram ensinados a partir de experimentos clássicos em uma sala totalmente dedicada ao Sol, a Sala Solar com equipamentos de baixo custo. Os cursos enfatizaram atividades práticas, observacionais e questionadoras, como discussões sobre a natureza do Sol, manchas solares e proeminências, estimativas da temperatura da fotosfera, observaçã do espectro solar na região do visível e identicação das linhas de absorção entendendo como são produzidas e que tipo de informações podem ser extraídas a partir delas. O objetivo do curso do ensino fundamental foi mostrar que o Sol e um astro dinâmico e que influencia a Terra de diversas maneiras, além de contextualizar o conteúudo ensinado com atividades práticas. O objetivo do curso do ensino médio foi compreender o papel chave desempenhado pela espectroscopia na astrofísica e permitir abordagens interdisciplinares incluíndo física moderna e química no ensino de Astronomia. A metodologia de pesquisa consistiu de uma abordagem qualitativa com a realização de questionários escritos, entrevistas semi-estruturadas e lmagens. Antes dos cursos, muitos alunos concebiam o Sol como sendo uma esfera quente de fogo, as manchas solares como sendo buracos no Sol e as proeminências como magma expelido por vulcões. Após a realizaçã dos cursos os alunos apresentaram ideias sobre o Sol e aspectos de física solar mais próximas das aceitas hoje em dia pela comunidade cientca. Esta pesquisa não ficou restrita aos ganhos cognitivos dos alunos após a realização dos minicursos, pois considerou a interação de diferentes contextos responsáveis pela aprendizagem em museus de ciências. Isso foi possível pelo referencial teórico adotado: o Modelo Contextual de Aprendizagem de Falk e Dierking. Trabalhar conteudos astronômicos de forma interdisciplinar e ao mesmo tempo de maneira ativa e questionadora traz alguns desafios para as equipes de instituições como o Observatório. As atividades elaboradas nos centros de ciências devem ter como principal objetivo despertar o interesse do aprendiz pela ciência, mas também destacamos a necessidade da oferta de minicursos para voluntários, pois a linguagem, conteúdos e metodologias em atividades mais longas podem facilitar abordagens interdisciplinares e integradoras da Astronomia com outras áreas do conhecimento científico pouco exploradas nas salas de aula. Isso pode ocorrer quando o projeto pedagógico da escola é construído coletivamente, envolvendo museus de ciências, professores, escola e alunos buscando conciliar propostas de um ensino de ciências que considere o contexto fora da escola e que ao mesmo tempo tenha relação com o que o aluno está estudando em sala de aula. / Observatories and planetariums offer the possibility of developing contextualized astronomy teaching by fostering educational activities that provide access to a more authentic school science. Thus, this research consisted in developing, applying and evaluating courses about the Sun for middle, junior high school students and solar physics for high school students in an informal educational space, the CDCC/USP Astronomical Observatory. Topics of chemical composition, temperature and stellar evolution were taught in a room totally dedicated to the study of the Sun, a Solar Room, designed with simple and inexpensive equipment. The course strongly emphasized practical, observational and inquirybased activities, such as estimation of the solar surface temperature, observation of the visible solar spectrum, identication of solar absorption lines, understanding how they are produced, and what kind of information can be extracted from the observed spectral lines. Some of the course goals were to foster the comprehension of the key role played by spectroscopy in astrophysics, to contextualize contents with practical activities, and to allow interdisciplinary approaches including modern physics and chemistry in physics teaching. The research methodology consisted of a qualitative approach by fillming the whole course and performing written questionnaires and semi-structured interviews. Before the courses were applied most students conceived the Sun as a hot sphere composed of fire, sunspots as holes in the Sun and solar prominences as magma expelled by volcanoes. After the courses students presented ideas about the Sun and solar physics more closely related to the ones accepted by contemporary science. This research was not restricted to students\' cognitive gains after concluding the courses, since it considered the interaction of different contexts responsible for learning in science museums. This was possible due to the theoretical framework adopted: The Contextual Model of Learning of Falk and Dierking. Some challenges have to be faced by institutions such as the Astronomical Observatory in order to teach astronomy in an interdisciplinary form and with inquiry-based activities The activities developed at science centers must have as their main objective to motivate the public towards science, but it is also important to offer courses for volunteers, since language, contents and methodologies in longer activities can facilitate interdisciplinary approaches of Astronomy with other areas of scientic knowledge seldom explored in classrooms. This can happen when the school\'s educational project is collectively constructed including science museums, teachers, school and students by seeking to enhance teaching proposals that consider the out of school context and is related to contents taught in the classroom.
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Desenvolvimento de método cromatográfico para determinação de ingredientes ativos de formulações fotoprotetoras e uso da fluorescência de raios-x para a determinação do fator de proteção solar / Development of chromatographic method for the determination of active ingredients in suscreen formulations and use of X-ray fluorescence to determine the sun protection factorPeruchi, Livia Maniero, 1982- 08 February 2010 (has links)
Orientador: Susanne Rath / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T08:45:18Z (GMT). No. of bitstreams: 1
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Previous issue date: 2010 / Resumo: Este trabalho teve como objetivo desenvolver e validar um método por cromatografia líquida de alta eficiência para a determinação de oito compostos ativos amplamente utilizados em protetores solares: benzofenona-3, octocrileno, metil benzilideno canfora, octil dimetil PABA, metoxicinamato de etilexila, butil metoxidibenzoilmetano, homosalato (usado nas suas duas formas isoméricas) e salicilato de etilexila. A separação dos compostos foi realizada em uma coluna cromatográfica ACE C18 (250 mm x 4.6 mm, 5 mm), na temperatura de 20 °C e fase movel composta por metanol:agua 88:12 v/v com eluição isocrática. A vazão foi de 1 mL min e a quantificação foi feita por padronização externa no comprimento de onda máximo de cada composto. O tempo da corrida cromatográfica foi de 18 minutos. O preparo de amostra consistiu basicamente de diluição e filtração anterior quantificação. Os parâmetros considerados na validação do método foram: faixa linear, linearidade, sensibilidade, precisão intra e inter-ensaio e exatidão. O método foi aplicado em treze amostras de diferentes fabricantes disponíveis comercialmente. O número de compostos ativos variaram entre 1 e 5 em uma mesma amostra. As concentrações dos compostos estão na faixa de 0,9-10% (m/m) e estão de acordo com o limite máximo permitido pela ANVISA. Este trabalho teve tambem como objetivo avaliar a potencialidade do uso de fluorescência de raios-X para determinar o FPS (fator de proteção solar) de protetores solares utilizando métodos quimiométricos. Para isso foram selecionadas varias amostras de um mesmo fabricante com diferentes FPS. Os espectros de raios-X obtidos foram tratados com a ferramenta quimiométrica PCA (Principal Component Analysis) para a análise exploratória dos dados e então construiu-se um modelo de calibração por PLS (Partial Least Squares). / Abstract: This work describes the development and validation of a HPLC-DAD method for determination of eight sunscreen agents: benzophenone-3, octocrylene, octyl methoxycinnamate, octyl salicylate, homosalate (used in two isomeric forms), butyl metoxydibenzoylmethane, 4-metylbenzylidene camphor and octyl dimetyl PABA in sunscreen formulations. The separation of the eight compounds were achieved using a ACE C18 column (250 mm x 4.6 mm, 5 mm), column temperature 20 °C, and a mobile phase of 88:12 (v/v) methanol-water with isocratic elution. The flow rate was 1 mL/min and quantitation was performed by external calibration at the maximum wavelength of each compound. Total run time was 18 minutes. The sample preparation was simple and consisted basically of dilution and filtration before quantitation. The critical points of the method are the column temperature, composition of the C18 stationary phase and the composition of the mobile phase. The validation parameters comprised: linear range, linearity, selectivity, intra-day and inter-day precision, and accuracy, and were in accordance with the aim of the method. Thirteen samples of sunscreen emulsions (SPF 30) of different manufacturer were analyzed. The number of the sunscreen agents varied between one and five in a same sample. The concentrations of all compounds were in the range of 0.9 to 10% (m/m) and were in accordance with the current Brazilian legislation. This work has also evaluated the potential of use of X-ray fluorescence to determine the SPF (sun protection factor) of sunscreens using chemometric methods. For this purpose, several samples from the same manufacturer (same components) with different FPS were selected. The X-ray spectra obtained were treated with a chemiometric tool PCA (Principal Component Analysis) for exploratory data analysis and then built a calibration model by PLS (Partial Least Squares). / Mestrado / Mestre em Química
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