Dissertations / Theses: 'SOLAP'

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Silva, Ricardo Filipe. "SOLAP+." Master's thesis, Faculdade de Ciências e Tecnologia, 2010. http://hdl.handle.net/10362/4973.

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Trabalho apresentado no âmbito do Mestrado em Engenharia Informática,como requisito parcial para obtenção do grau de Mestre em Engenharia Informática
No início do século XXI, Bédard propôs incorporar ao modelo multi-dimensional dados geográficos, originando o conceito SOLAP. Através deste conceito, os analistas puderam obter melhores análises das estruturas e relações de dados espaciais, mantendo as características benéficas que provêm dos sistemas OLAP, isto é, informação sumarizada, análise de dados a diferentes níveis de granularidade, exploração interactiva dos dados, etc. Devido à adequação dos sistemas SOLAP, face aos sistemas OLAP para o processo de suporte à decisão, algumas aplicações têm sido desenvolvidas. Porém, estas aplicações têm sido concebidas para um contexto específico. Com o propósito de se transpor esta limitação, vários foram os trabalhos que culminaram num modelo genérico SOLAP. Apesar de este modelo solucionar diversas limitações de aplicações anteriores, actualmente, não suporta análises com duas entidades espaciais em simultâneo, por exemplo “total de voos entre o aeroporto para o aeroporto ” ou “qual a quantidade de resíduos lançados por uma indústria no rio ?”. Por outro lado, a visualização dos mapas pode despoletar o efeito contrário ao desejado. Facilmente o mapa poderá ficar desorganizado devido ao excesso de objectos geográficos presentes, o que prejudica a visualização/análise de dados espaciais. Para dar resposta a estas questões, esta dissertação pretende estender o modelo SOLAP genérico, de modo a suportar análises onde estão presentes duas entidades espaciais em simultâneo e integrar algoritmos de agrupamento espacial, com o objectivo de garantir a visibilidade do mapa em situações de excesso de objectos geográficos.

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Jorge, Ruben. "SOLAP+: extending the interaction model." Master's thesis, Faculdade de Ciências e Tecnologia, 2009. http://hdl.handle.net/10362/5912.

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Thesis submitted to Faculdade de Ciências e Tecnologia of the Universidade Nova de Lisboa, in partial fulfillment of the requirements for the degree of Master in Computer Science
Decision making is a crucial process that can dictate success or failure in today’s businesses and organizations. Decision Support Systems (DSS) are designed in order to help human users with decision making activities. Inside the big family of DSSs there is OnLine Analytical Processing (OLAP) - an approach to answer multidimensional queries quickly and effectively. Even though OLAP is recognized as an efficient technique and widely used in mostly every area, it does not offer spatial analysis, spatial data visualization nor exploration. Geographic Information Systems (GIS) had a huge growth in the last years and acquiring and storing spatial data is easier than ever. In order to explore this potential and include spatial data and spatial analysis features to OLAP, Bédard introduced Spatial OLAP (SOLAP). Although it is a relatively new area, many proposals towards SOLAP’s standardization and consolidation have been made,as well as functional tools for different application areas. There are however many issues and topics in SOLAP that are either not covered or with incompatible/non general proposals. We propose to define a generic model for SOLAP interaction based on previous works, extending it to include new visualization options,components and cases; create and present a component-driven architecture proposal for such a tool, including descriptive metamodels, aggregate navigator to increase perfomance and a communication protocol; finally, develop an example prototype that partially implements the proposed interaction features, taking into consideration guidelines for a user friendly, yet powerful and flexible application.

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Santos, Manuel António Carvalho. "Visualização cartográfica assistida num ambiente SOLAP." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10168.

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Dissertação para obtenção do Grau de Mestre em Engenharia Informática
O conceito Spatial OLAP introduz a visualização cartográfica nos sistemas Business Intelligent/OLAP. Esta tem grandes potencialidades para melhorar a análise de grandes quantidades de dados georreferenciados e o respetivo processo de tomada de decisão. O potencial que é possível obter da visualização cartográfica depende fortemente do uso apropriado não só das variáveis visuais como também de outros elementos que possam ser utilizados para representar informação no mapa (ex.: gráficos). Porém, num ambiente SOLAP, o analista deveria estar apenas focado em procurar informação útil abstraindo-se de como deve ser construída uma visualização cartográfica adequada. Neste trabalho, é proposto um modelo para assistir o utilizador na construção de visualizações cartográficas. O modelo proposto considera: (i) a meta-informação existente sobre os modelos multidimensionais; (ii) a interrogação realizada; (iii) os dados resultantes. Através do modelo proposto, pretende-se assistir o utilizador na construção de mapas temáticos apropriados. Neste trabalho é proposto: (i) um modelo para descrever tipos de visualização; (ii) um modelo para descrever o contexto analítico SOLAP; (iii) uma metodologia para a seleção adequada dos tipos de visualização aplicáveis em cada contexto analítico SOLAP e sua instanciação. O modelo de cartografia assistida em ambiente SOLAP proposto neste trabalho foi implementado sobre protótipo SOLAP+.

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ANDRADE, Ana Cecília Vital de. "Arquitetura e Interface Gráfica para um Cliente SOLAP." Universidade Federal de Pernambuco, 2014. https://repositorio.ufpe.br/handle/123456789/10489.

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Submitted by Lucelia Lucena (lucelia.lucena@ufpe.br) on 2015-03-04T18:33:54Z No. of bitstreams: 2 DISSERTAÇÃO Ana Cecília Vital de Andrade.pdf: 4377501 bytes, checksum: 62069caff1753987554f40017f60aa10 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5)
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SOLAP é uma tecnologia resultante da integração das ferramentas OLAP (Online Analytical Processing) e SIG (Sistemas de Informação Geográfica), cujo objetivo é proporcionar novas possibilidades de análises, uma vez que permite integrar processamento espacial (SIG) e processamento multidimensional-multinível (OLAP) (e.g., qual foi o total de produtos vendidos por loja, cliente, ano, semestre e mês para os clientes que residem até 1km da matriz?). Embora existam muitos trabalhos relacionados à SOLAP, poucos dão atenção à especificação do cliente SOLAP. Neste contexto, ressalta-se que a maioria dos trabalhos existentes apenas dá suporte à manipulação de uma única dimensão espacial e apresentam poucos (algumas vezes nenhum) detalhes sobre a arquitetura e/ou recursos visuais para especificar e sincronizar graficamente operações OLAP e SIG em um cliente SOLAP. Visando propor uma alternativa ao problema descrito, esta dissertação especifica e implementa uma arquitetura de software e uma interface gráfica para um cliente SOLAP Web, o qual visa especificar graficamente operações SOLAP sobre uma ou mais dimensões espaciais, bem como sobre temas externos ao cubo de dados. Como prova de conceito, foi realizado um exemplo de uso do cliente SOLAP construído, que testa a realização de operações SOLAP com as características citadas.

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Pastor, Julien. "Conception d'une légende interactive et forable pour le SOLAP." Thesis, Université Laval, 2004. http://www.theses.ulaval.ca/2004/21994/21994.pdf.

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Afin de palier au manque d'efficacité des SIG en tant qu'outil d'aide à la décision (granularités multiples, rapidité, convivialité, temporalité), différentes saveurs d'outils SOLAP (Spatial OLAP) ont vu le jour dans les centres de recherche et fournisseurs de logiciels (CRG/Kheops/Syntell, SFU/DBMiner, Proclarity, Cognos, Microsoft, Beyond 20/20, ESRI, MapInfo, etc.). Combinant des fonctions SIG avec l'informatique décisionnelle (entrepôts de données, OLAP, data mining), le SOLAP est décrit comme un "logiciel de navigation rapide et facile dans les bases de données spatiales qui offre plusieurs niveaux de granularité d’information, plusieurs époques, plusieurs thèmes et plusieurs modes de visualisation synchronisés ou non: cartes, tableaux et graphiques statistiques (Bédard 2004). Le SOLAP facilite l’exploration volontaire des données spatiales pour aider l'utilisateur à détecter les corrélations d’informations, les regroupements potentiels, les tendances dissimulées dans un amas de données à référence spatiale, etc. Le tout se fait par simple sélection/click de souris (pas de langage SQL) et des opérations simples comme : le forage, le remontage ou le forage latéral. Il permet à l’utilisateur de se focaliser sur les résultats des opérations au lieu de l’analyse du processus de navigation. Le SOLAP étant amené à prendre de l’essor au niveau des fonctions qu’il propose, il devient important de proposer des améliorations à son interface à l'usager de manière à conserver sa facilité d’utilisation. Le développement d’une légende interactive et forable fut la première solution en ce genre proposée par Bédard (Bédard 1997). Nous avons donc retenu cette piste pour la présente recherche, étudié la sémiologie graphique et son applicabilité à l'analyse multidimensionnelle, analysé ce qui existait dans des domaines connexes, exploré différentes alternatives permettant de résoudre le problème causé par l'enrichissement des fonctions de navigation, construit un prototype, recueilli des commentaires d'utilisateurs SOLAP et proposé une solution. Tout au long de cette recherche, nous avons été confrontés à une absence de littérature portant explicitement sur le sujet (les SOLAP étant trop nouveaux), à des corpus théoriques qu'il fallait adapter (sémiologie, interface homme-machine, visualisation scientifique, cartographie dynamique) et à des besoins en maquettes et prototypes pour illustrer les solutions envisagées. Finalement, cette recherche propose une solution parmi plusieurs; cependant, son principal intérêt est davantage l'ensemble des réflexions et considérations mises de l'avant tout au long du mémoire pour arriver au résultat proposé que la solution proposée en elle-même. Ce sont ces réflexions théoriques et pratiques qui permettront d'améliorer l'interface à l'usager de tout outil SOLAP grâce au nouveau concept de légende interactive et forable.

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Leão, Tiago Dias Silva. "Caracterização espacial utilizando indução orientada aos atributos no SOLAP+." Master's thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/6309.

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Dissertação para obtenção do Grau de Mestre em Engenharia Informática
O protótipo SOLAP+, desenvolvido sobre a orientação de João Moura Pires, segue o conceito SOLAP apresentado por Bédard et al. combinando as funcionalidades dos sistemas de apoio à decisão OLAP com as capacidades dos sistemas de informação geográfica (SIG). Com os trabalhos realizados por Rosa Martins (2006), Marlene Vitorino e Rodolfo Caldeira (2008), Ruben Jorge (2009) e Ricardo Silva (2010) foi desenvolvida uma abordagem genérica SOLAP que culminou com a implementação de um protótipo que, presentemente, já apresenta bastantes funcionalidades do ponto de vista da análise de dados e representação dos mesmos através de mapas temáticos e/ou gráficos. Para ajudar nessa tarefa de análise, integramos mecanismos de descoberta de relações entre os dados e apresentamos no mapa essas relações. Esta forma de análise permite ao utilizador retirar conclusões através da extracção de informações que não estão explícitas nos dados presentes na base de dados. Assim, o objectivo desta dissertação consiste em incorporar, respeitando o modelo multidimensional seguido, duas técnicas de indução: generalização de dominância espacial e generalização de dominância não espacial. Com os resultados da aplicação dessas técnicas, é feita uma caracterização semântica dos objectos espaciais no mapa.

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da, Silva Joel. "GEOMDQL: Uma Linguagem de Consulta geogr´afica e Multidimensional." Universidade Federal de Pernambuco, 2008. https://repositorio.ufpe.br/handle/123456789/1315.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Existem várias propostas na literatura visando a integração das funcionalidades e características pertinentes aos processamentos de dados analíticos (OLAP) e geográficos (SIG). O principal objetivo é prover um ambiente único, com capacidades de processamento geográfico e multidimensional, para dar suporte ao processo de tomada de decisões estratégicas. Este tipo de ambiente vem sendo referido atualmente como SOLAP. Entretanto, pelo fato destas duas tecnologias terem sido concebidas com propósitos distintos, a integração entre estes dois ambientes não é uma tarefa fácil, e mesmo com tantas pesquisas sendo desenvolvidas, temos alguns pontos em aberto que merecem ser explorados. A definição de modelos de dados para Data Warehouse Geográficos é um dos items desta integração. Outro ponto inserido neste contexto é a definição de funções de agregação para medidas geográficas. Estas funções são utilizadas no momento da especificação dos cubos de dados multidimensionais e geográficos. Conseqüentemente, também necessitamos de novos modelos de cubos de dados que possibilitem a associação de geometrias aos fatos e aos membros dos níveis. Uma das partes mais importantes desse processo de integração é a consulta aos dados. Porém, a maioria das abordagens que almejam esta integração de processamento, não dispõe de uma linguagem de consulta que possibilite a utilização simultânea, tanto de operadores multidimensionais como espaciais. É neste contexto que se insere esta tese, na qual apresentamos: i) um modelo formal para definição de DWG; ii) um conjunto de funções de agregação para medidas geográficas; iii) um modelo formal para cubos de dados chamado GeoMDCube; e iv) uma linguagem de consulta geográfica-multidimensional denominada GeoMDQL (Geographic Multidimensional Query Language). GeoMDQL estende e integra, em uma única sintaxe, os principais operadores multidimensionais e espaciais presentes na maioria das ferramentas e em ambientes disponíveis atualmente para processamento multidimensional e geográfico. GeoMDQL é baseada em padrões bem estabelecidos como ( MDX Multidimensional Expressions) e OGC Simple Features for SQL. As idéias propostas foram aplicadas na prática, por meio da implementação de uma arquitetura SOLAP chamada Golapware e o desenvolvimento de estudo de caso baseado em dados de aplicações reais. Dessa forma, foi possível demonstrar a utilização dos modelos, das funções e da linguagem de consulta e operadores SOLAP discutidos nesta tese

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Edoh-Alové, Djogbénuyè Akpé. "Handling spatial vagueness issues in SOLAP datacubes by introducing a risk-aware approach in their design." Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25957.

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Thèse en cotutelle: Université Laval Québec, Canada et Université Blaise-Pascal, Clermont-Ferrand, France
Les systèmes Spatial On-Line Analytical Processing (SOLAP) permettent de prendre en charge l’analyse multidimensionnelle en ligne d’un très grand volume de données ayant une référence spatiale. Dans ces systèmes, le vague spatial n’est généralement pas pris en compte, ce qui peut être source d’erreurs dans les analyses et les interprétations des cubes de données SOLAP, effectuées par les utilisateurs finaux. Bien qu’il existe des modèles d’objets ad-hoc pour gérer le vague spatial, l’implantation de ces modèles dans les systèmes SOLAP est encore à l’état embryonnaire. En outre, l’introduction de tels modèles dans les systèmes SOLAP accroit la complexité de l’analyse au détriment de l’utilisabilité dans bon nombre de contextes applicatifs. Dans cette thèse nous nous proposons d’investiguer la piste d’une nouvelle approche visant un compromis approprié entre l’exactitude théorique de la réponse au vague spatial, la facilité d’implantation dans les systèmes SOLAP existants et l’utilisabilité des cubes de données fournis aux utilisateurs finaux. Les objectifs de cette thèse sont donc de jeter les bases d’une approche de conception de cube SOLAP où la gestion du vague est remplacée par la gestion des risques de mauvaises interprétations induits, d’en définir les principes d’une implantation pratique et d’en démontrer les avantages. En résultats aux travaux menés, une approche de conception de cubes SOLAP où le risque de mauvaise interprétation est considéré et géré de manière itérative et en adéquation avec les sensibilités des utilisateurs finaux quant aux risques potentiels identifiés a été proposée; des outils formels à savoir un profil UML adapté, des fonctions de modification de schémas multidimensionnels pour construire les cubes souhaités, et un processus formel guidant de telles transformations de schémas ont été présentés; la vérification de la faisabilité de notre approche dans un cadre purement informatique avec la mise en œuvre de l’approche dans un outil CASE (Computed Aided Software Engineering) a aussi été présentée. Pour finir, nous avons pu valider le fait que l’approche fournisse non seulement des cubes aussi compréhensibles et donc utilisables que les cubes classiques, mais aussi des cubes où le vague n’est plus laissé de côté, sans aucun effort pour atténuer ses impacts sur les analyses et les prises de décision des utilisateurs finaux.
SOLAP (Spatial On-Line Analytical Processing) systems support the online multi-dimensional analysis of a very large volume of data with a spatial reference. In these systems, the spatial vagueness is usually not taken into account, which can lead to errors in the SOLAP datacubes analyzes and interpretations end-users make. Although there are ad-hoc models of vague objects to manage the spatial vagueness, the implementation of these models in SOLAP systems is still in an embryonal state. In addition, the introduction of such models in SOLAP systems increases the complexity of the analysis at the expense of usability in many application contexts. In this thesis we propose to investigate the trail of a new approach that makes an appropriate compromise between the theoretical accuracy of the response to the spatial vagueness, the ease of implementation in existing SOLAP systems and the usability of datacubes provided to end users. The objectives of this thesis are to lay the foundations of a SOLAP datacube design approach where spatial vagueness management in itself is replaced by the management of risks of misinterpretations induced by the vagueness, to define the principles of a practical implementation of the approach and to demonstrate its benefits. The results of this thesis consist of a SOLAP datacube design approach where the risks of misinterpretation are considered and managed in an iterative manner and in line with the end users tolerance levels regarding those risks; formal tools namely a suitable UML (Unified Modeling Language) profile, multidimensional schemas transformation functions to help tailored the datacubes to end-users tolerance levels, and a formal process guiding such schemas transformation; verifying the feasibility of our approach in a computing context with the implementation of the approach in a CASE (Computed Aided Software Engineering) tool. Finally, we were able to validate that the approach provides SOLAP datacubes that are not only as comprehensible and thus usable as conventional datacubes but also datacubes where the spatial vagueness is not left out, with no effort to mitigate its impacts on analysis and decision making for end users.

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Guimond, Louis-Étienne. "Conception d'un environnement de découverte des besoins pour le développement de solutions SOLAP." Thesis, Université Laval, 2005. http://www.theses.ulaval.ca/2005/22406/22406.pdf.

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Un problème dans la réalisation de projets SOLAP est la difficulté des utilisateurs à exprimer leurs besoins et leurs attentes en début d'analyse de système. Cette technologie étant totalement nouvelle, les utilisateurs ne découvrent tout son potentiel qu'après une certaine période d'utilisation et c'est à ce moment que de nouveaux besoins surgissent. Nos travaux ont donc pour objectif principal de faciliter l’analyse en proposant un environnement de découverte des besoins des utilisateurs. Pour cela, nous proposons le concept de maquettage d’apprentissage pour accélérer l’apprentissage de la solution par les utilisateurs et pour leur suggérer de nouvelles possibilités. Cela leur permet de rapidement définir leurs besoins généraux et de mieux concevoir et exprimer de nouveaux besoins plus détaillés. Nous élaborons aussi des scénarios pour intégrer le maquettage dans un processus de développement. Puis, nous concevons un outil de maquettage basé sur des caractéristiques du maquettage d’application SOLAP identifiées dans notre recherche.

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Zaamoune, Mehdi. "Intégration et optimisation des grilles régulières de points dans une architecture SOLAP relationnelle." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22538/document.

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Les champs continus sont des types de représentations spatiales utilisées pour modéliser des phénomènes tels que la température, la pollution ou l’altitude. Ils sont définis selon une fonction de mapping f qui affecte une valeur du phénomène étudié à chaque localisation p du domaine d’étude. Par ailleurs, la représentation des champs continus à différentes échelles ou résolutions est souvent essentielle pour une analyse spatiale efficace. L’avantage des champs continus réside dans le niveau de détails généré par la continuité, ainsi que la qualité de l’analyse spatiale fournie par la multi-résolution. L’inconvénient de ce type de représentations dans l’analyse spatio-multidimensionnelle est le coût des performances d’analyse et de stockage. Par ailleurs, les entrepôts de données spatiaux et les systèmes OLAP spatiaux (EDS et SOLAP) sont des systèmes d’aide à la décision qui permettent l’analyse spatio-multidimensionnelle de grands volumes de données spatiales et non spatiales. L’analyse des champs continus dans l’architecture SOLAP représente un défi de recherche intéressant. Différents travaux se sont intéressés à l’intégration de ce type de représentations dans le système SOLAP. Cependant, celle-ci est toujours au stade embryonnaire. Cette thèse s’intéresse à l’intégration des champs continus incomplets représentés par une grille régulière de points dans l’analyse spatio-multidimensionnelle. Cette intégration dans le système SOLAP implique que l’analyse des champs continus doit supporter : (i) les opérateurs OLAP classiques, (ii) la vue continue des données spatiales, (iii) les opérateurs spatiaux (slice spatial) et (iv) l’interrogation des données à différentes résolutions prédéfinies. Dans cette thèse nous proposons différentes approches pour l’analyse des champs continus dans le SOLAP à différents niveaux de l’architecture relationnelle, de la modélisation conceptuelle à l’optimisation des performances de calcul. Nous proposons un modèle logique FISS qui permet d’optimiser les performances d’analyse à multi-résolution en se basant sur des méthodes d’interpolation. Puis, nous exposons une méthodologie basée sur la méthode d’échantillonnage du Clustering, qui permet d’optimiser les opérations d’agrégation des grilles régulières de points dans l’architecture SOLAP relationnelle en effectuant une estimation des résultats
Continuous fields are types of spatial representations used to model phenomena such as temperature, pollution or altitude. They are defined according to a mapping function f that assigns a value of the studied phenomenon to each p location of the studied area. Moreover, the representation of continuous fields at different scales or resolutions is often essential for effective spatial analysis. The advantage of continuous fields is the level of details generated by the continuity of the spatial data, and the quality of the spatial analysis provided by the multi-resolution. The downside of this type of spatial representations in the multidimensionnal analysis is the high cost of analysis and storage performances. Moreover, spatial data warehouses and spatial OLAP systems (EDS and SOLAP) are decision support systems that enable multidimensional spatial analysis of large volumes of spatial and non-spatial data. The analysis of continuous fields in SOLAP architecture represents an interesting research challenge. Various studies have focused on the integration of such representations in SOLAP system. However, this integration still at an early stage. Thus, this thesis focuses on the integration of incomplete continuous fields represented by a regular grid of points in the spatio-multidimensional analysis. This integration in the SOLAP system involves that the analysis of continuous fields must support:(i) conventional OLAP operators, (ii) Continuous spatial data, (iii) spatial operators (spatial slice), and (iv) querying data at different predefined levels of resolutions. In this thesis we propose differents approaches for the analysis of continuous fields in SOLAP system at different levels of the relational architecture (from the conceptual modeling to the optimization of computing performance). We propose a logical model FISS to optimize the performances of the multi-resolution analysis, based on interpolation methods. Then, we present a new methodology based on the Clustering sampling method, to optimize aggregation operations on regular grids of points in the relational SOLAP architecture

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Brito, Jaqueline Joice. "Processamento de consultas SOLAP drill-across e com junção espacial em data warehouses geográficos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-18022013-090739/.

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Um data warehouse geográco (DWG) é um banco de dados multidimensional, orientado a assunto, integrado, histórico, não-volátil e geralmente organizado em níveis de agregação. Além disso, também armazena dados espaciais em uma ou mais dimensões ou em pelo menos uma medida numérica. Visando oferecer suporte à tomada de decisão, é possível realizar em DWGs consultas SOLAP (spatial online analytical processing ), isto é, consultas analíticas multidimensionais (e.g., drill-down, roll-up, drill-across ) com predicados espaciais (e.g., intersecta, contém, está contido) denidos para range queries e junções espaciais. Um desafio no processamento dessas consultas é recuperar, de forma eficiente, dados espaciais e convencionais em DWGs muito volumosos. Na literatura, existem poucos índices voltados à indexação de DWGs, e ainda assim nenhum desses índices dedica-se a indexar consultas SOLAP drill-across e com junção espacial. Esta dissertação visa suprir essa limitação, por meio da proposta de estratégias para o processamento dessas consultas complexas. Para o processamento de consultas SOLAP drill-across foram propostas duas estratégias, Divide e Única, além da especicação de um conjunto de diretrizes que deve ser seguido para o projeto de um esquema de DWG que possibilite a execução dessas consultas e da especicação de classes de consultas. Para o processamento de consultas SOLAP com junção espacial foi proposta a estratégia SJB, além da identicação de quais características o esquema de DWG deve possuir para possibilitar a execução dessas consultas e da especicação do formato dessas consultas. A validação das estratégias propostas foi realizada por meio de testes de desempenho considerando diferentes congurações, sendo que os resultados obtidos foram contrastados com a execução de consultas do tipo junção estrela e o uso de visões materializadas. Os resultados mostraram que as estratégias propostas são muito eficientes. No processamento de consultas SOLAP drill-across, as estratégias Divide e Única mostraram uma redução no tempo de 82,7% a 98,6% com relação à junção estrela e ao uso de visões materializadas. No processamento de consultas SOLAP com junção espacial, a estratégia SJB garantiu uma melhora de desempenho na grande maioria das consultas executadas. Para essas consultas, o ganho de desempenho variou de 0,3% até 99,2%
A geographic data warehouse (GDW) is a special kind of multidimensional database. It is subject-oriented, integrated, historical, non-volatile and usually organized in levels of aggregation. Furthermore, a GDW also stores spatial data in one or more dimensions or at least in one numerical measure. Aiming at decision support, GDWs allow SOLAP (spatial online analytical processing) queries, i.e., multidimensional analytical queries (e.g., drill-down, roll-up, drill-across) extended with spatial predicates (e.g., intersects, contains, is contained) dened for range and spatial join queries. A challenging issue related to the processing of these complex queries is how to recover spatial and conventional data stored in huge GDWs eciently. In the literature, there are few access methods dedicated to index GDWs, and none of these methods focus on drill-across and spatial join SOLAP queries. In this master\'s thesis, we propose novel strategies for processing these complex queries. We introduce two strategies for processing SOLAP drill-across queries (namely, Divide and Unique), dene a set of guidelines for the design of a GDW schema that enables the execution of these queries, and determine a set of classes of these queries to be issued over a GDW schema that follows the proposed guidelines. As for the processing of spatial join SOLAP queries, we propose the SJB strategy, and also identify the characteristics of a DWG schema that enables the execution of these queries as well as dene the format of these queries. We validated the proposed strategies through performance tests that compared them with the star join computation and the use of materialized views. The obtained results showed that our strategies are very ecient. Regarding the SOLAP drill-across queries, the Divide and Unique strategies showed a time reduction that ranged from 82,7% to 98,6% with respect to star join computation and the use of materialized views. Regarding the SOLAP spatial join queries, the SJB strategy guaranteed best results for most of the analyzed queries. For these queries, the performance gain of the SJB strategy ranged from 0,3% to 99,2% over the star join computation and the use of materialized view

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Edoh-Alove, Djogbénuyè Akpé. "Proposition d'une nouvelle méthode de conception de cubes SOLAP exploitant des données spatiales vagues." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22566/document.

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Les systèmes Spatial On-Line Analytical Processing (SOLAP) permettent de prendre en charge l’analyse multidimensionnelle en ligne d’un très grand volume de données ayant une référence spatiale. Dans ces systèmes, le vague spatial n’est généralement pas pris en compte, ce qui peut être source d’erreurs dans les analyses et les interprétations des cubes de données SOLAP, effectuées par les utilisateurs finaux. Bien qu’il existe des modèles d’objets ad-hoc pour gérer le vague spatial, l’implantation de ces modèles dans les systèmes SOLAP est encore à l’état embryonnaire. En outre, l’introduction de tels modèles dans les systèmes SOLAP accroit la complexité de l’analyse au détriment de l’utilisabilité dans bon nombre de contextes applicatifs. Dans cette thèse nous nous proposons d’investiguer la piste d’une nouvelle approche visant un compromis approprié entre l’exactitude théorique de la réponse au vague spatial, la facilité d’implantation dans les systèmes SOLAP existants et l’utilisabilité des cubes de données fournis aux utilisateurs finaux.Les objectifs de cette thèse sont donc de jeter les bases d’une approche de conception de cube SOLAP où la gestion du vague est remplacée par la gestion des risques de mauvaises interprétations induits, d’en définir les principes d’une implantation pratique et d’en démontrer les avantages.En résultats aux travaux menés, une approche de conception de cubes SOLAP où le risque de mauvaise interprétation est considéré et géré de manière itérative et en adéquation avec les sensibilités des utilisateurs finaux quant aux risques potentiels identifiés a été proposée; des outils formels à savoir un profil UML adapté, des fonctions de modification de schémas multidimensionnels pour construire les cubes souhaités, et un processus formel guidant de telles transformations de schémas ont été présentés; la vérification de la faisabilité de notre approche dans un cadre purement informatique avec la mise en oeuvre de l’approche dans un outil CASE (Computed Aided Software Engineering) a aussi été présentée. Pour finir, nous avons pu valider le fait que l’approche fournisse non seulement des cubes aussi compréhensibles et donc utilisables que les cubes classiques, mais aussi des cubes où le vague n’est plus laissé de côté, sans aucun effort pour atténuer ses impacts sur les analyses et les prises de décision des utilisateurs finaux
SOLAP (Spatial On-Line Analytical Processing) systems support the online multi-dimensional analysis of a very large volume of data with a spatial reference. In these systems, the spatial vagueness is usually not taken into account, which can lead to errors in the SOLAP datacubes analyzes and interpretations end-users make. Although there are ad-hoc models of vague objects to manage the spatial vagueness, the implementation of these models in SOLAP systems is still in an embryonal state. In addition, the introduction of such models in SOLAP systems increases the complexity of the analysis at the expense of usability in many application contexts. In this thesis we propose to investigate the trail of a new approach that makes an appropriate compromise between the theoretical accuracy of the response to the spatial vagueness, the ease of implementation in existing SOLAP systems and the usability of datacubes provided to end users.The objectives of this thesis are to lay the foundations of a SOLAP datacube design approach where spatial vagueness management in itself is replaced by the management of risks of misinterpretations induced by the vagueness, to define the principles of a practical implementation of the approach and to demonstrate its benefits.The results of this thesis consist of a SOLAP datacube design approach where the risks of misinterpretation are considered and managed in an iterative manner and in line with the end users tolerance levels regarding those risks; formal tools namely a suitable UML (Unified Modeling Language) profile, multidimensional schemas transformation functions to help tailored the datacubes to end-users tolerance levels, and a formal process guiding such schemas transformation; verifying the feasibility of our approach in a computing context with the implementation of the approach in a CASE (Computed Aided Software Engineering) tool. Finally, we were able to validate that the approach provides SOLAP datacubes that are not only as comprehensible and thus usable as conventional datacubes but also datacubes where the spatial vagueness is not left out, with no effort to mitigate its impacts on analysis and decision making for end users

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Dubé, Étienne. "Conception et développement d'un service Web de constitution de mini cubes SOLAP pour clients mobiles." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25804/25804.pdf.

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Les applications d’aide à la décision spatiale telles que SOLAP (Spatial OLAP) sont traditionnellement conçues pour les environnements informatiques de bureau. L’adaptation des applications SOLAP aux contextes d’utilisation mobile (e.g. PDA et téléphones mobiles) pose certains problèmes dus à la nature et aux contraintes de ces environnements. Ce projet de recherche vise à apporter une solution, basée sur une architecture orientée services (SOA), pour l’adaptation des cubes de données SOLAP aux environnements mobiles. Il s’agit d’un service Web capable de transformer les cubes SOLAP des entrepôts de données géo-décisionnelles en mini-cubes de taille réduite, adaptés aux clients mobiles. Le service permet de sélectionner un sous-ensemble des cubes existants par l’intermédiaire d’opérateurs paramétrables, d’appliquer des traitements de simplification aux membres spatiaux, et finalement de transmettre ces données en format XML. Ce travail de recherche ouvre donc la voie à la conception et au développement de nouvelles applications géospatiales décisionnelles mobiles.
Decision support systems such as SOLAP (Spatial OLAP) have been originally designed as desktop applications. Adapting SOLAP applications to mobility contexts (e.g. using PDAs and mobile phones) pose some challenges due to the constraints of these environments. This research projects aims to provide a solution, based on a Service Oriented Architecture (SOA), for adapting SOLAP data cubes to mobile environments. It consists of a Web service which is capable of transforming SOLAP cubes from spatial data warehouses, in order to create mini-cubes of reduced size, suitable for mobile clients. This service allows selecting a subset of existing cubes (using parameterizable operators), applying simplification algorithms to spatial members, and finally transfering the data in an XML format. This research opens the way to the design and development of new geospatial decisional mobile applications.

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Lambert, Mélanie. "Développement d'une approche pour l'analyse solap en temps réel : adapatation aux besoins des activités sportives en plein air." Thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/23469/23469.pdf.

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Au cours des dernières années, différents types de travaux ont été réalisés indépendamment au sein du même centre de recherche (Centre de Recherche en Géomatique de l’Université Laval). Parmi ceux-ci, on retrouve des travaux axés sur l’acquisition et le traitement des données spatiales en sport de plein air d’une part, et des travaux axés sur l’exploration et l’analyse des données spatiales avec une solution SOLAP d’autre part. L’exploitation conjointe de ces travaux permettait de répondre à de nouvelles attentes et plus particulièrement à une nouvelle application : l’évaluation et l’analyse de la performance d’athlètes pratiquant un sport extérieur grâce à des données calculées à partir d’observations GPS. En effet, suite à des observations GPS, la position, la vitesse et l’accélération de l’athlète peuvent être calculées précisément. Cependant, aucun logiciel ne permettait d’analyser rapidement et facilement les nouvelles données recueillies. Pourtant, les entraîneurs d’athlètes de haut niveau désirent obtenir des données sur les performances actuelles, de façon rapide et exacte, pour ainsi adapter immédiatement leur entraînement et favoriser le succès de l’athlète. Or, la technologie SOLAP offre aux utilisateurs une interface cliente très intuitive pour l’analyse spatio-temporelle. Cependant, son fonctionnement ne permettait pas d’ajouter rapidement de nouvelles données obtenues à partir d’observations GPS. Cette recherche visait alors à développer une approche répondant à des besoins d’analyse SOLAP en temps réel retrouvés dans certaines applications et plus particulièrement dans le sport de haut niveau. Nous avons aussi vérifié qu’une solution SOLAP utilisée dans le domaine de la gestion des entreprises pour faciliter les prises de décision peut être transposée dans celui de l'analyse de la performance des athlètes. Pour ce faire, un SOLAP juste-à-temps, baptisé SOLAP-SPORT, a été développé dans le cadre de ce projet de recherche.

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McHugh, Rosemarie. "Intégration de la structure matricielle dans les cubes spatiaux." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25758/25758.pdf.

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Dans le monde de la géomatique, la fin des années 1990 a été marquée par l’arrivée de nouvelles solutions décisionnelles, nommées SOLAP. Les outils SOLAP fournissent des moyens efficaces pour facilement explorer et analyser des données spatiales. Les capacités spatiales actuelles de ces outils permettent de représenter cartographiquement les phénomènes et de naviguer dans les différents niveaux de détails. Ces fonctionnalités permettent de mieux comprendre les phénomènes, leur distribution et/ou leurs interrelations, ce qui améliore le processus de découverte de connaissances. Toutefois, leurs capacités en termes d’analyses spatiales interactives sont actuellement limitées. Cette limite est principalement due à l’unique utilisation de la structure de données géométrique vectorielle. Dans les systèmes d’information géographique (SIG), la structure de données matricielle offre une alternative très intéressante au vectoriel pour effectuer certaines analyses spatiales. Nous pensons qu’elle pourrait offrir une alternative intéressante également pour les outils SOLAP. Toutefois, il n’existe aucune approche permettant son exploitation dans de tels outils. Ce projet de maîtrise vise ainsi à définir un cadre théorique permettant l’intégration de données matricielles dans les SOLAP. Nous définissons les concepts fondamentaux permettant l’intégration du matriciel dans les cubes de données spatiaux. Nous présentons ensuite quelques expérimentations qui ont permis de les tester et finalement nous initions le potentiel du matriciel pour l’analyse spatiale dans les outils SOLAP.

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Lévesque, Marie-Andrée. "Approche formelle pour une meilleure identification et gestion des risques d'usages inappropriés des données géodécisionnelles." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25565/25565.pdf.

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L’utilisation croissante de l’information géographique a soulevé d’importantes inquiétudes au cours de la dernière décennie quant aux risques d’usages inappropriés des données géospatiales, particulièrement par des usagers profanes ou non experts en référence spatiale. Ces inquiétudes ont récemment augmenté avec l’arrivée de nouvelles technologies simples et rapides, dont la nouvelle catégorie d’outils d’aide à la décision dénommée SOLAP (Spatial On-Line Analytical Processing). En effet, les nouvelles capacités d’analyse offertes par ces outils ouvrent la porte à un plus grand nombre d’utilisateurs qui peuvent potentiellement ne pas tenir compte adéquatement des forces, faiblesses et qualités inhérentes aux données analysées. En réponse à cette problématique, ce projet de maîtrise propose une approche générique, prenant en compte les obligations juridiques des fournisseurs de données, permettant d’identifier et de gérer des risques d’usages inappropriés des données géodécisionnelles utilisées par les applications SOLAP. Les principes énoncés pourraient éventuellement être transposés aux systèmes non décisionnels (SIG).
Inscrite au Tableau d'honneur de la Faculté des études supérieures

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Beaulieu, Véronique. "Étude de la visualisation géographique dans un environnement d'exploration interactive de données géodécisionnelles : adaptation et améliorations." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26354/26354.pdf.

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La visualisation géographique de l’information est un aspect important du SOLAP. Elle est le troisième élément clé pour supporter une analyse facile, rapide et intuitive des données prônée par l’approche SOLAP. Cependant, à ce jour, aucune étude ne s’est intéressée spécifiquement à cet aspect du SOLAP et les stratégies de visualisation utilisées traditionnellement dans les SIG ne conviennent pas à l’approche interactive et multidimensionnelle. Ce mémoire présente une recherche exploratoire proposant premièrement de placer la visualisation géographique au cœur de la relation entre l’utilisateur et la base de données. Cette stratégie fait ressurgir plusieurs besoins et possibilités explorées au cours de ce mémoire. Le respect de la flexibilité d’analyse SOLAP, les divers types de visualisation nécessaires pour rendre les différents types de requêtes, puis les manipulations graphiques qui peuvent s’opérer dans un environnement SOLAP font l’objet de propositions. Deuxièmement, ce mémoire propose une méthode permettant une relation directe entre les données et leur visualisation, sans l’intermédiaire de l’utilisateur. La solution théorique résultante respecte la philosophie d’exploration interactive prônée par l'approche SOLAP. Elle suggère l’intégration de l’expertise en visualisation géographique à l’intérieur même de la technologie SOLAP par l’ajout de métadonnées et d’une base de connaissances sémiologiques. Ce premier pas vers une amélioration du processus de visualisation avec SOLAP ouvre la porte à plusieurs recherches ultérieures.

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LEITE, Daniel Farias Batista. "Processamento analítico espacial e exploratório integrando dados estruturados e semiestruturados." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/746.

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CNPq
Tecnologias de Business Intelligence (BI) têm sido utilizadas com sucesso para fins de análise de dados. Tradicionalmente, essa análise é realizada em um contexto restrito e bem controlado, onde as fontes de dados são estruturadas, periodicamente carregadas, estáticas e totalmente materializadas. Atualmente, há uma diversidade de dados nos mais diversos formatos, a exemplo de RDF (Resource Description Framework), um formato semiestruturado, semanticamente rico e externo à infraestrutura de BI. Embora tal formato seja enriquecido semanticamente, e muitas vezes possua um componente espacial, realizar a análise é um desafio. Nessa perspectiva, uma nova categoria de ferramentas analíticas vem surgindo. As ferramentas exploratórias (Exploratory OLAP), como são conhecidas, se caracterizam pela descoberta, aquisição e integração de dados externos em ambientes comuns de análise. Do nosso conhecimento, até a presente data, existem apenas duas ferramentas exploratórias propostas na literatura e elas apresentam duas grandes limitações: exploram apenas fontes de dados estruturadas; e não há exploração do componente espacial dos dados integrados. São ferramentas exploratórias OLAP, e não ferramentas exploratórias SOLAP. Baseando-se nessas ferramentas, este trabalho propõe uma abordagem exploratória SOLAP que integra dados semiestruturados espaciais semânticos com fontes de dados estruturados espaciais tradicionais. Um sistema, denominado ExpSOLAP, que dá suporte a consultas SOLAP on-line sob as duas fontes de dados foi desenvolvido. Por fim, o sistema ExpSOLAP é avaliado através de um exemplo prático, no contexto da base de dados obtida no Linked Movie Data Base, utilizando RDF e banco de dados relacional. Foram formuladas consultas que validaram a análise convencional e espacial na exploração de ambas fontes de dados.
Business Intelligence (BI) technologies have been successfully applied for data analysis purposes. Traditionally, such analysis is performed in well-controlled and restricted context, where data sources are structured, periodically loaded, static and fully materialized. Nowadays, there is a plenty of data in different formats such as the Resource Description Framework (RDF), a semi-structured and semantically rich format external to the BI infrastructure. Although such data formats are enriched by semantics and contains a spatial data component, performing data analysis is challenging. As a result, the Exploratory OLAP field has emerged for discovery, acquisition, integration and query such data, aiming at performing a complete and effective analysis on both internal and external data. To the best of our knowledge, there are only two exploratory tools proposed in the literature and they have two major limitations due to only structured data sources can be explored and there is no exploration of the spatial component of the integrated data. While they are exploratory OLAP tools, they are not exploratory SOLAP tools. Based on these tools, this work proposes an Exploratory SOLAP approach that integrates semantic spatial semi-structured data with traditional spatial structured data sources. A system named ExpSOLAP, which supports online SOLAP queries on both data sources, was developed. Finally, a case study was carried out in order to evaluate the ExpSOLAP system based on a dataset originating from the Linked Movie Data Base and using RDF and relational datasets. The formulated queries enabled to validate the conventional and spatial analysis from both data sources.

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Rageul, Nicolas. "Vers une optimisation du processus d'analyse en ligne de données 3D : cas des fouilles archéologiques." Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24791/24791.pdf.

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L'archéologie est une discipline des sciences humaines dont l'objet d'étude est l'ensemble des vestiges matériels laissés par l'Homme (objets, bâtiments, infrastructures, paysages...). Une technique précise, la fouille, est employée afin de tirer toutes les informations possibles des sols et structures fouillés en tenant compte de la localisation exacte des objets découverts, de l'étude de la succession des différentes couches de terrain déblayé afin de pouvoir procéder à une datation stratigraphique. L’analyse d’une fouille archéologique demande souvent beaucoup d’efforts pour l’archéologue car, à ce jour, aucun système informatique n’a permis de clairement les aider dans l’analyse de leurs données. Ainsi, pour exploiter des données issues d’une fouille archéologique, nous avons identifié trois critères : la rapidité et la facilité d’utilisation, la possibilité de faire évoluer les données dans le système (les interprétations de l'archéologue suivant des heuristiques qui ne peuvent pas toujours être formalisées de façon absolue) et la visualisation tridimensionnelle. L’outil d’analyse en ligne de type SOLAP est optimisé pour une analyse interactive dite multidimensionnelle où les requêtes, même celles de types agrégatives sont simples et leurs réponses sont rapides. Reste donc à l’optimiser sur les deux autres critères retenus pour exploiter les données issues d’une fouille archéologique et qui marquent les principales faiblesses de l’outil : l’évolution des données pendant la phase d’analyse et l’intégration de la 3e dimension. Ce projet de maîtrise vise à apporter des nouveaux concepts permettant à un utilisateur de réviser ces données pendant sa phase d’analyse. Par la suite, un prototype appliqué à l’archéologie a été élaboré afin de vérifier simplement si les efforts pour réviser des données pouvaient être compatibles avec les efforts d’un outil d’analyse en ligne en conservant la fluidité d’exploration interactive. D’autre part, ce projet de maîtrise a permis d’étudier la faisabilité d’un SOLAP 3D et de soulever une interrogation sur la nécessité d’introduire la 3e dimension à un outil d’analyse en ligne.

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Boulil, Kamal. "Une approche automatisée basée sur des contraintes d’intégrité définies en UML et OCL pour la vérification de la cohérence logique dans les systèmes SOLAP : applications dans le domaine agri-environnemental." Thesis, Clermont-Ferrand 2, 2012. http://www.theses.fr/2012CLF22285/document.

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Les systèmes d'Entrepôts de Données et OLAP spatiaux (EDS et SOLAP) sont des technologies d'aide à la décision permettant l'analyse multidimensionnelle de gros volumes de données spatiales. Dans ces systèmes, la qualité de l'analyse dépend de trois facteurs : la qualité des données entreposées, la qualité des agrégations et la qualité de l’exploration des données. La qualité des données entreposées dépend de critères comme la précision, l'exhaustivité et la cohérence logique. La qualité d'agrégation dépend de problèmes structurels (e.g. les hiérarchies non strictes qui peuvent engendrer le comptage en double des mesures) et de problèmes sémantiques (e.g. agréger les valeurs de température par la fonction Sum peut ne pas avoir de sens considérant une application donnée). La qualité d'exploration est essentiellement affectée par des requêtes utilisateur inconsistantes (e.g. quelles ont été les valeurs de température en URSS en 2010 ?). Ces requêtes peuvent engendrer des interprétations erronées des résultats. Cette thèse s'attaque aux problèmes d'incohérence logique qui peuvent affecter les qualités de données, d'agrégation et d'exploration. L'incohérence logique est définie habituellement comme la présence de contradictions dans les données. Elle est typiquement contrôlée au moyen de Contraintes d'Intégrité (CI). Dans cette thèse nous étendons d'abord la notion de CI (dans le contexte des systèmes SOLAP) afin de prendre en compte les incohérences relatives aux agrégations et requêtes utilisateur. Pour pallier les limitations des approches existantes concernant la définition des CI SOLAP, nous proposons un Framework basé sur les langages standards UML et OCL. Ce Framework permet la spécification conceptuelle et indépendante des plates-formes des CI SOLAP et leur implémentation automatisée. Il comporte trois parties : (1) Une classification des CI SOLAP. (2) Un profil UML implémenté dans l'AGL MagicDraw, permettant la représentation conceptuelle des modèles des systèmes SOLAP et de leurs CI. (3) Une implémentation automatique qui est basée sur les générateurs de code Spatial OCL2SQL et UML2MDX qui permet de traduire les spécifications conceptuelles en code au niveau des couches EDS et serveur SOLAP. Enfin, les contributions de cette thèse ont été appliquées dans le cadre de projets nationaux de développement d'applications (S)OLAP pour l'agriculture et l'environnement
Spatial Data Warehouse (SDW) and Spatial OLAP (SOLAP) systems are Business Intelligence (BI) allowing for interactive multidimensional analysis of huge volumes of spatial data. In such systems the quality ofanalysis mainly depends on three components : the quality of warehoused data, the quality of data aggregation, and the quality of data exploration. The warehoused data quality depends on elements such accuracy, comleteness and logical consistency. The data aggregation quality is affected by structural problems (e.g., non-strict dimension hierarchies that may cause double-counting of measure values) and semantic problems (e.g., summing temperature values does not make sens in many applications). The data exploration quality is mainly affected by inconsistent user queries (e.g., what are temperature values in USSR in 2010?) leading to possibly meaningless interpretations of query results. This thesis address the problems of logical inconsistency that may affect the data, aggregation and exploration qualities in SOLAP. The logical inconsistency is usually defined as the presence of incoherencies (contradictions) in data ; It is typically controlled by means of Integrity Constraints (IC). In this thesis, we extends the notion of IC (in the SOLAP domain) in order to take into account aggregation and query incoherencies. To overcome the limitations of existing approaches concerning the definition of SOLAP IC, we propose a framework that is based on the standard languages UML and OCL. Our framework permits a plateforme-independent conceptual design and an automatic implementation of SOLAP IC ; It consists of three parts : (1) A SOLAP IC classification, (2) A UML profile implemented in the CASE tool MagicDraw, allowing for a conceptual design of SOLAP models and their IC, (3) An automatic implementation based on the code generators Spatial OCLSQL and UML2MDX, which allows transforming the conceptual specifications into code. Finally, the contributions of this thesis have been experimented and validated in the context of French national projetcts aimming at developping (S)OLAP applications for agriculture and environment

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Boulil, Kamal. "Une approche automatisée basée sur des contraintes d'intégrité définies en UML et OCL pour la vérification de la cohérence logique dans les systèmes SOLAP : Applications dans le domaine agri-environnemental." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00923497.

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Les systèmes d'Entrepôts de Données et OLAP spatiaux (EDS et SOLAP) sont des technologies d'aide à la décision permettant l'analyse multidimensionnelle de gros volumes de données spatiales. Dans ces systèmes, la qualité de l'analyse dépend de trois facteurs : la qualité des données entreposées, la qualité des agrégations et la qualité de l'exploration des données. La qualité des données entreposées dépend de critères comme la précision, l'exhaustivité et la cohérence logique. La qualité d'agrégation dépend de problèmes structurels (e.g. les hiérarchies non strictes qui peuvent engendrer le comptage en double des mesures) et de problèmes sémantiques (e.g. agréger les valeurs de température par la fonction Sum peut ne pas avoir de sens considérant une application donnée). La qualité d'exploration est essentiellement affectée par des requêtes utilisateur inconsistantes (e.g. quelles ont été les valeurs de température en URSS en 2010 ?). Ces requêtes peuvent engendrer des interprétations erronées des résultats. Cette thèse s'attaque aux problèmes d'incohérence logique qui peuvent affecter les qualités de données, d'agrégation et d'exploration. L'incohérence logique est définie habituellement comme la présence de contradictions dans les données. Elle est typiquement contrôlée au moyen de Contraintes d'Intégrité (CI). Dans cette thèse nous étendons d'abord la notion de CI (dans le contexte des systèmes SOLAP) afin de prendre en compte les incohérences relatives aux agrégations et requêtes utilisateur. Pour pallier les limitations des approches existantes concernant la définition des CI SOLAP, nous proposons un Framework basé sur les langages standards UML et OCL. Ce Framework permet la spécification conceptuelle et indépendante des plates-formes des CI SOLAP et leur implémentation automatisée. Il comporte trois parties : (1) Une classification des CI SOLAP. (2) Un profil UML implémenté dans l'AGL MagicDraw, permettant la représentation conceptuelle des modèles des systèmes SOLAP et de leurs CI. (3) Une implémentation automatique qui est basée sur les générateurs de code Spatial OCL2SQL et UML2MDX qui permet de traduire les spécifications conceptuelles en code au niveau des couches EDS et serveur SOLAP. Enfin, les contributions de cette thèse ont été appliquées dans le cadre de projets nationaux de développement d'applications (S)OLAP pour l'agriculture et l'environnement.

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Simões, Carlos Enrique Hernández. "Geovisualização analítica: desenvolvimento de um protótipo de um sistema analítico de informações para a gestão da coleta seletiva de resíduos urbanos recicláveis." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-17082010-111747/.

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Os resíduos urbanos descartados de forma irregular constituem um problema sério, principalmente nas grandes cidades, causando entupimento de bueiros e drenagem com conseqüentes inundações, sujeira e transmissão de doenças tais como leptospirose e dengue além de ser um estorvo para o trânsito e acarretarem gastos para a Prefeitura. Por outro lado, reciclar este material é uma fonte de receitas e um gerador de empregos. A Geovisualização Analítica pode ser de grande auxílio para a análise desse problema complexo e para a tomada de decisão. Com essa motivação, a presente dissertação procura fornecer uma visão geral sobre o estado da arte quanto a conceitos e pesquisas em Geovisualização (GVis) e Processamento Analítico (OLAP e SOLAP). Apresenta também processos, metodologias e tecnologias que foram utilizadas no desenvolvimento de um protótipo de um sistema analítico de informações aplicado à área de gestão da coleta seletiva de resíduos sólidos recicláveis em ambiente urbano. Este protótipo, efetivamente implantado, combinou navegação e consulta para recuperar informações através de seleções espaciais e alfanuméricas. Através de exemplos foi mostrado que este tipo de solução auxilia gestores nos processos de exploração, análise e tomada de decisão.
Domestic waste illegally disposed constitute a serious problem, especially in large cities, causing clogging of drains and drainage with subsequent flooding, dirt and transmission of diseases such as leptospirosis and dengue as well as being a hindrance to traffic and would entail city hall costs. Moreover, recycle this material is a source of revenue and a generator of jobs. The Analytical Geovisualization can be of great help in the analysis of this complex problem and the decision-making. With this motivation, this paper seeks to provide an overview of the state of the art as the concepts and research in Geovisualization (GVis) and Analytical Processing (OLAP and SOLAP). It also presents processes, methodologies and technologies that were used in developing a prototype of an analytical system applied to the area of selective collection information management of recyclable solid waste in urban environments. This prototype, effectively deployed, combined navigation and query to retrieve information through spatial and alphanumeric selections. Through examples it was shown that this type of solution helps managers in operating procedures, analysis and decision making.

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Sholin, Veronica. "Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2008. http://uclibs.org/PID/11984.

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Berryman, Ian. "Optimisation, design, development, and trial of a low-cost solar oven with novel concentrator geometry." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:42de9b33-18e1-4f22-8a44-3ddfd532bd0b.

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A promising and novel solar concentrator design has been thoroughly investigated and optimised. A prototype concentrator based on this novel geometry was validated using ray tracing techniques. This ray tracing demonstrated the comparative performance of this novel concentrator in regards to equivalent parabolic dishes. The effect of mirror surface normal errors on performance was established using Monte-Carlo based ray tracing code, which agreed well with the optical performance of this prototype which was determined experimentally. A need for low-cost solar cookers to replace bio-mass worldwide was identified, and the concentrator design was then developed as a low-cost solar oven. Despite existing in some number, no current design is able to achieve high performance at low-cost. An industrial partner, Dytecna, was initially involved in the process of this development of the system as a solar cooker. In support of a field trial for the solar cooker developed with Dytecna, a detailed thermal model of the oven was developed. A low-cost lightmeter was constructed and calibrated in order to measure the direct normal irradiance during the field trial in Italy. Laboratory work provided baseline results for the heating of various thermal masses in the oven. The Italian field trials provided a wealth of feedback into the design of the system and many valuable results. The solar cooker was able to bring 0.75L of water to the boil in 33 minutes with an average heat throughput of 203W. Important benchmark results and practical experience of several competing receiver materials was obtained; further lab testing provided more accurate measurements of the receivers' performances. The experiences of the Italian field trial were fed back into the design of a subsequent prototype, intended for a much larger field trial in Tanzania. Improvements in the hotplate, receiver material, and the oven were all incorporated into the design. Additionally, the structure of the solar cooker was redesigned to incorporate a low-cost wooden construction. Supporting work was conducted for the month long trial in which 8 solar cookers would be distributed to families in Tanzania. The field trial in Tanzania provided a wealth of user feedback into the design. At the same time the new solar cooker exceeded previously established performances in Italy. The new design was able to provide an average of 246W of heat to 1kg of water, which was brought to boiling point in 25 minutes. This represents a heating efficiency of 66% compared to the incident solar flux on the hotplate. In response to findings during the Tanzanian trials, further laboratory work was conducted into establishing the reflectivities of low-cost candidate mirror materials. Throughout all phases of the project the design of the solar cooker was refined and improved with the goal of a solar cooker design that could reach price-point, performance, and usability standards which would ensure market success.

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Reusswig, Philip David. "Sensitized energy transfer for organic solar cells, optical solar concentrators, and solar pumped lasers." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93831.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 123-130).
The separation of chromophore absorption and excitonic processes, such as singlet exciton fission and photoluminescence, offers several advantages to the design of organic solar cells and luminescent solar concentrators (LSCs) for the end goal of achieving a lower cost solar energy generation. This thesis explores three new device architectures to overcome limited solar absorption in singlet-exciton-fission based solar cells and neodymium based LSCs. The process of singlet exciton fission is de-coupled from photon absorption, exciton diffusion, and charge transport in singlet-exciton-fission based solar cells by inserting a singlet fission material at the donor-acceptor interface of an organic solar cell. Singlet excitons generated in the singlet exciton donor are transferred to the singlet fission material through near field energy transfer. In this device structure, the singlet donor can be chosen for high photon absorption, exciton diffusion, and charge transport, and the singlet fission sensitizer can be selected for high singlet fission efficiency. We demonstrated a doubling of the external quantum efficiency from 12.8% to 27.6% in a singlet donor (TPTPA) through the introduction of thin film singlet fission sensitizer (rubrene) for high efficiency organic solar cells. To reduce the cost of electricity generated by sunlight via LSC systems, replacing the expensive high efficiency visible photovoltaic (PV) elements with cheap, high efficiency, earth abundant near-infrared PV elements made with silicon. This requires replacing within the LSC the visible emitting chromophores with near infrared emitters. Here, we present the use of a lanthanide ion, neodymium--colloidal nanocrystal energy cascade system as a promising LSC emitter scheme for the silicon spectral region. Peak optical quantum efficiencies of 43% in a Nd³+:glass based LSC are demonstrated with simulated high geometric gain performance. With cascade energy transfer, the optical quantum efficiency in the visible of a Nd³+:glass is significantly improved with peak efficiency of 28%. The enhanced solar absorption of Nd³+:glass through cascade energy transfer can be extended into the infrared with more optimal sensitizers. The idea of directly converting broad-band solar radiation into coherent and narrow-band laser radiation could enable many attractive technologies for solar energy. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-[mu]m-thick Nd³+-doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 20 W-cm2 , or approximately 200 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.
by Philip David Reusswig.
Ph. D.

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Enshayan, Kamyar Short Ted H. "Measurement of solar radiation transmission in solar ponds /." Connect to resource, 1989. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1145375001.

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Mahoney, Luther. "Solar hydrogen and solar electricity using mesoporous materials." Thesis, University of South Dakota, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3723927.

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The development of cost-effective materials for effective utilization of solar energy is a major challenge for solving the energy problems that face the world. This thesis work relates to the development of mesoporous materials for solar energy applications in the areas of photocatalytic water splitting and the generation of electricity. Mesoporous materials were employed throughout the studies because of their favorable physico-chemical properties such as high surface areas and large porosities. The first project was related to the use of a cubic periodic mesoporous material, MCM-48. The studies showed that chromium loading directly affected the phase of mesoporous silica formed. Furthermore, within the cubic MCM-48 structure, the loading of polychromate species determined the concentration of solar hydrogen produced. In an effort to determine the potential of mesoporous materials, titanium dioxide was prepared using the Evaporation-Induced Self-Assembly (EISA) synthetic method. The aging period directly determined the amount of various phases of titanium dioxide. This method was extended for the preparation of cobalt doped titanium dioxide for solar simulated hydrogen evolution. In another study, metal doped systems were synthesized using the EISA procedure and rhodamine B (RhB) dye sensitized and metal doped titania mesoporous materials were evaluated for visible light hydrogen evolution. The final study employed various mesoporous titanium dioxide materials for N719 dye sensitized solar cell (DSSC) materials for photovoltaic applications. The materials were extensively characterized using powder X-ray diffraction (XRD), nitrogen physisorption, diffuse reflectance spectroscopy (DRS), UV-Vis spectroscopy, Fourier-Transform-Infrared Spectroscopy (FT-IR), Raman spectroscopy, chemisorption, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). In addition, photoelectrochemical measurements were completed using current-voltage (I-V) curves, external quantum efficiency (EQE) curves, electrochemical impedance spectroscopy (EIS), and transient spectroscopy. The thesis work presented provides a better understanding of the role of mesoporous materials for solar hydrogen and solar electricity production.

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Parand, Foroutan. "Solar energy utilisation and evacuated tubular solar collectors." Thesis, Brunel University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292989.

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Enshayan, Kamyar. "Measurement of solar radiation transmission in solar ponds." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1145375001.

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Fallows, R. A. "Studies of solar wind throughout a solar cycle." Thesis, Aberystwyth University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594095.

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Karlsson, Jimmy. "Solar tracker." Thesis, Uppsala universitet, Signaler och System, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387629.

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We are facing a climate crisis, and the world needs to generate electricity in more climate neutral ways. One alternative is to use solar energy. The highest efficiency can be achieved if the surface normal is pointed towards the sun, instead of just having it stationary. To solve this, people make a system called a solar tracker. In this project a prototype of a solar tracker is made, which can follow the sun in any direction. The solar tracker consists of a mechanical structure, two DC-motors that move the structure, and a microcontroller that implements the regulator to control the motors. All the mechanical parts were constructed and then printed using a 3D-printer. Manual control was implemented for making troubleshooting and testing easier. The electrical system is soldered on an experimental board and then mounted with the motor driver and mechanical construction on a bottom structure. There are a few interesting things that could be further developed. One is to implement sensors at the start point and end point of the sun tracking so that the tracker can return to the starting point after the sunset. It would be interesting to scale up the construction a bit and make some more useful measurements on larger panels to see if the system is energy effective enough to be useful; to make some outdoor tests and see how the sensors and control system work in a real-world environment; and to investigate and eventually develop its ability to adapt to cloudy weather.

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Zomer, Clarissa Debiazi. "Megawatt Solar." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/93727.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Civil, Florianópolis, 2010
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A inserção de geradores convencionais de energia geralmente ocorre em locais afastados dos grandes centros urbanos, pois tende a acarretar problemas para o entorno como poluição do ar, poluição sonora e poluição visual. No entanto, com a energia cada vez mais necessária para o desenvolvimento humano, utilizar a fonte de geração próxima ao ponto de consumo é uma maneira eficaz de reduzir as perdas por transmissão e distribuição (T&D), Neste contexto, destaca-se a energia solar fotovoltaica, que, além de gerar eletricidade de forma distribuída, diferenciando-se da forma como se constitui o setor elétrico brasileiro, é inesgotável, silenciosa, estática, extremamente simples em sua operação, possui característica modular e pode integrar-se a edificações. Tem-se então, através da geração fotovoltaica, a oportunidade de instalar geradores limpos, renováveis e silenciosos em meio urbano. O objetivo desta dissertação é analisar a inserção do que poderia ser o maior gerador fotovoltaico da América do Sul de que se tem notícia até o presente, integrado ao envelope da edificação da Eletrosul, empresa do setor elétrico, localizada em área urbana de Florianópolis - SC. Através do estudo de área disponível na edificação e suas áreas adjacentes, quantificou-se o potencial fotovoltaico existente na Eletrosul. A partir daí, estimou-se a geração fotovoltaica horária, mensal e anual, a fim de comparar com o consumo da edificação. Com 1 MWp instalado, a contribuição anual seria de 31% do consumo energético, chegando a 42% no mês de dezembro. Na comparação horária, verificaram-se momentos de geração energética superior ao consumo, resultando em energia injetada na rede. Como o consumo e a geração fotovoltaica apresentaram curvas semelhantes, constatou-se a possibilidade de uma recontratação de demanda pela empresa, agregando mais valor à integração fotovoltaica. Por fim, analisou-se a participação da geração deste sistema de grande porte na redução de consumo energético no alimentador em que a edificação está inserida. Neste caso, a contribuição foi de 5% do consumo anual. Através das análises, pode-se quantificar a contribuição energética de um gerador fotovoltaico de grande porte tanto para a edificação quanto para o alimentador em que ela está inserida.

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Invidiata, Andrea. "Solar Decathlon." reponame:Repositório Institucional da UFSC, 2013. https://repositorio.ufsc.br/handle/123456789/106838.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-graduação em Arquitetura e Urbanismo, Florianópolis, 2013.
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O progresso e a pesquisa para tornar os edifícios mais eficientes e, ao mesmo tempo, mais confortáveis, vêm sendo o foco do novo conceito de arquitetura. Um exemplo de como essa evolução está sendo concretizada é o Solar Dechatlon, uma competição (criada em 2002) entre universidades do mundo todo que projetam e constroem casas autossuficientes energeticamente, pois operam utilizando apenas energia solar. A competição visa a construção de casas extremamente eficientes, avaliadas em diferentes quesitos, dentre os quais está a eficiência energética. Em setembro de 2012, foi sediada em Madri e na Espanha, contando pela primeira vez com uma equipe brasileira, representada pela Ekó House. O projeto da Ekó House foi realizado considerando as condições climáticas de Madri, no mês de setembro, para conseguir o melhor desempenho possível da casa durante a competição. A casa, no panorama brasileiro, não apresenta a mesma eficiência que na cidade da competição, com um balanço energético final que só as cidades de Brasília, Montes Claros e Goiânia têm um resultado parecido com a cidade de Madri. Esta pesquisa de Mestrado, portanto, tem o objetivo de avaliar a casa nas diferentes zonas bioclimáticas brasileiras por meio de três metodologias distintas (balanço energético, RTQ-R prescritivo e RTQ-R simulação) e propor, para cada região, um modelo adaptado às condições das diferentes cidades brasileiras analisadas. O objetivo da pesquisa é reutilizar o projeto Ekó House no Brasil da maneira mais eficiente para as condições climáticas do país, e, ao mesmo tempo, criar uma referência projetual para futuras participações na competição Solar Decathlon, tendo como foco, além da competição, a aplicação da casa no território brasileiro. A revisão bibliográfica é centrada em um melhor conhecimento da competição Solar Decathlon e da casa brasileira, abordando também os temas de arquitetura bioclimática e da eficiência energética nas edificações, tendo como foco o uso de tecnologias de energia solar. Por fim, uma análise das normas brasileiras relacionadas à eficiência energética nas edificações concluirá a revisão bibliográfica. A metodologia, por sua vez, é baseada na análise quantitativa da casa na cidade da competição e nas cidades brasileiras escolhidas. A avaliação da eficiência energética da casa será feita por meio de três métodos de análise diferentes: balanço energético, método prescritivo do RTQ-R e método de simulação do RTQ-R. Por último, a casa será alterada nas diferentes regiões, de acordo com as entrevistas feitas com os membros da equipe, com as normas brasileiras e de análise climática das cidades ! onde a casa será avaliada. Dessa forma, será obtido para cada cidade um modelo de casa Ekó House mais eficiente. Os resultados finais demonstram que a casa obteve um melhor desempenho energético por meio das alterações de projeto propostas em todas as cidades brasileiras. As cidades com condições climáticas mais quentes apresentaram um maior benefício das alterações de projeto aportadas, reduzindo o consumo em até 20% comparado com o projeto original da casa

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Elluru, Shailaja. "Solar vehicles." OpenSIUC, 2021. https://opensiuc.lib.siu.edu/theses/2824.

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Transportation-related greenhouse gas emissions are one of the most serious environmental concerns, and they are rising at an alarming pace. As a result, solar energy for transportation might be able to solve this problem. The aim of the proposed work is to contribute a technology that promotes Renewable energy; for example, imagine a situation in which we might use solar energy to charge electric cars that have solar panels-built in. solar powered vehicles that can collect and store solar power during their daily trips in their onboard solar batteries These cars can store some solar energy in the batteries and can run smoothly at night and also in the absence of sunlight. As vehicles return to their base stations, they move their Excess power collection to bigger base station batteries, which can be used later.

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Morini, Matteo. "Solar Wheel." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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L'elaborato tratta una particolare ruota solare prodotta da Marand, usata per le competizioni automobilistiche solari. Dopo un'introduzione, che spiega chi è Marand, in cosa consiste la ruota a grandi linee e gli aspetti generali di cui tenere conto, segue una descrizione dei componenti principali che formano la ruota ed infine la procedura per smontarla/montarla.

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Nawas, Yousef Ibrahim. "Solar House." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/9753.

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The Solar House is an investigation that resulted from an inter-disciplinary, design built competition ( the Solar Decathlon). This event was sponsored by the U.S. Department of Energy in an atempt to integrate architecture, technology, and dwelling. The investigation focused on making a house using matter as a conduit to the spiritual, by emphasising two different natures in contrasting conditions. At the same time inclusive of all the technological aspects of a building that operates on solar energy, embedded with the complexities of building systems and new materials.
Master of Architecture

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Bafana, Ramzi, and Zain Zulfiqar. "Solar Energy." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2079.

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This thesis is about Photovoltaic (PV) cells and its stresses in various directions by calculating the power generated using solar cells under different conditions to improve its efficiency. Our research studies found that using multi-junction cells with larger substrates can increase the efficiency to some extent which in practice is limited to 43 percent. The experiment was conducted using ten solar cells each with an area of 20.9〖cm〗 ^2, where each cell gives 0.5 V and 0.4 A and a 1.25 Ω resistor was used. The cells were connected in series. Once, the PV cells were fixed horizontally and the other time tested in tilted position under same outdoor condition. The purpose of testing PV cells was to investigate the efficiency under above mentioned conditions. The data collected from the readings was used in calculation, and we have obtained from the calculations that horizontally fixed cells gave 4.8 percent efficiency whereas tilted cells gave 6.6 percent efficiency. Hence, the ratio showed that fixed cells produced 37.5 percent more power compared to horizontally fixed cells. Our other experiment consisted of testing PV cells under different temperature conditions that was done using a freezer and an oven for temperature variation and a tungsten bulb was used as a light source. The purpose of performing this experiment was to investigate how the efficiency of PV cells is affected under extreme conditions. Part of our thesis was also including studies and analysis of produced energy by the solar panel installed on the roof of “BTH” building in Karlskrona, Sweden. The data consisted of energy produced from February up to August 2014. The investigation also included finding the highest produced energy during these months. We have found that the highest energy was generated on the 1st of July which was 12.86 kWh. Furthermore, we went deep into investigation of the 1st of July to know exactly which hour of that day the highest energy was produced. The data showed that the highest produced energy was at 12:19 and 13:19 which was 2.03 kWh.
Ramzi: +46723231353, +966561993488 Zain:

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Serio, Ulises Daniel. "Energía solar." Bachelor's thesis, Universidad Nacional de Cuyo. Facultad de Ciencias Económicas, 2012. http://bdigital.uncu.edu.ar/5250.

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La energía solar posee un enorme potencial, por ejemplo, si un 10% del desierto de Sahara fuera instalado con paneles solares (suponiendo una efectividad de captación de radiación del 10%), produciría una cantidad de energía eléctrica equivalente al doble del consumo eléctrico mundial. De este modo no existe un problema de recursos o fuentes de energía, sino un problema de costos (actualmente, la energía solar es 10 veces más cara de producir que la provista por una central térmica tradicional) y las demás formas limpias de generar electricidad (hidroeléctrica, geotérmica, mareomotriz, eólica, etc.) no poseen la capacidad técnica de alimentar al planeta dado los recursos limitados de las mismas (Lackner y Sachs 2005). En Argentina el uso de este tipo de tecnología es todavía muy limitado. No obstante ha aumentado recientemente la popularidad del uso de la energía solar (y calefones solares) en la región de Cuyo haciendo verdaderamente importante un estudio sobre si esta tendencia es correcta y conviene a la sociedad o si sus recursos serían mejor invertidos en otras tecnologías o gastos (incluso dentro del ámbito energético). Un aspecto que resulta importante evaluar es la conveniencia de la implementación de estas tecnologías desde el punto de vista económico-privado ya que de esta manera se pueden direccionar acciones de políticas tendientes a incentivar el uso de las mismas.
Fil: Serio, Ulises Daniel. Universidad Nacional de Cuyo. Facultad de Ciencias Económicas.

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Bolton, Kirk G. Gravagne Ian A. "Design of a solar thermal collector simulator." Waco, Tex. : Baylor University, 2009. http://hdl.handle.net/2104/5317.

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Freitas, Flavio Santos 1982. "Eletrodos de materiais inorgânicos modificados para células solares híbridas." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248430.

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Orientador: Ana Flávia Nogueira
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-23T23:53:53Z (GMT). No. of bitstreams: 1 Freitas_FlavioSantos_D.pdf: 16885434 bytes, checksum: 48b960051e69118d4e3bbf7bc096a552 (MD5) Previous issue date: 2013
Resumo: Este trabalho apresenta a síntese de moléculas carboxiladas e sua utilização como agentes compatibilizantes em sistemas híbridos inorgânico/orgânico. A caracterização e aplicação das interfaces destes sistemas híbridos de dióxido de titânio com poli(3-hexiltiofeno) (TiO2/P3HT) e silício monocristalino com poli(3-hexiltiofeno) (Si/P3HT) também foram estudadas. No primeiro sistema, TiO2/P3HT, a modificação superficial do TiO2 foi efetuada com três moléculas carboxiladas: ácido 2-tiofenocarboxílico (TCA), ácido 2-tiofenoacético (TAA) e ácido 2,4-tiofenodicarboxílico (TDA). Essas modificações demostraram que a molécula TAA apresenta melhor compatibilidade na interface, evidenciada por estudos fotofísicos de Espectroscopia de Absorção Transiente (TAS) e medidas de ângulo de contato. A célula solar com TAA (configuração invertida) apresentou eficiência de 0,03%, três vezes maior que a obtida no dispositivo padrão. Com a inserção do corante N719 na superfície do TiO2, a eficiência alcançou valores superiores a 1%. A eficiência dos dispositivos chegou a 1,35% com a inserção na camada de P3HT de nanopartículas de TiO2 na forma de bastão (TiO2 NB/TAA). Essa modificação da camada polimérica mostrou que o TiO2 NB/TAA apresentou propriedades ligeiramente superiores nos experimentos de fotoeletroquímica quando comparado com nanopartículas sintetizadas no formato esférico (TiO2 NE). Além disso, a técnica de Espalhamento de Raios-X a Baixo Ângulo (SAXS) mostrou que as nanopartículas TiO2 NB/TAA e TiO2 NE encontram-se distribuídas de forma homogênea pela matriz de P3HT. No segundo sistema, as células solares de Si/P3HT foram obtidas a partir de reações que modificaram a interface dos materiais. A adsorção química da molécula TAA sobre o óxido nativo (Si/SiOx/TAA) e a reação do grupo superficial Si-Cl com o reagente de Grignard brometo de tiofeno-magnésio (Si/Tiofeno) foram respectivamente caracterizadas por Espectroscopia de Infravermelho (FTIR) e Espectroscopia de Fotoelétrons por Raios-X (XPS). A contribuição do P3HT para o dispositivo foi avaliada a partir da comparação com uma junção Schottky (Al/Si/Au). Os valores de VOC obtidos nas células solares na presença de P3HT foram similares (~0,4 V) e superiores ao obtido no dispositivo sem o polímero (~0,2 V), evidenciando o domínio da junção Si/P3HT para as propriedades fotovoltaicas. O dispositivo Si/SiOx/TAA apresentou grande resistência em série, com eficiência de conversão de energia inferior a 0,5%. Porém, com a configuração Al/Si/Tiofeno/P3HT/Au, as células solares alcançaram valores de eficiência de 5,76%. A eficiência superior foi relacionada com a melhor adesão e compatibilidade entre o Si e o P3HT a partir de imagens de SEM
Abstract: This work presents the synthesis of carboxylated molecules and their use as compatibilizer agents in hybrid inorganic/organic systems. Characterization and application of the interfaces of those hybrid systems comprising titanium dioxide with poly(3-hexylthiophene) (TiO2/P3HT) and monocrystalline silicon with poly(3-hexylthiophene) (Si/P3HT) will also be described. In the former system, TiO2/P3HT, the TiO2 surface was modified with three molecules: 2-thiophenecarboxylic acid (TCA), 2-thiopheneacetic acid (TAA) and 2,4- thiophenedicarboxylic acid (TDA). Transient Absorption Spectroscopy (TAS) photophysical studies and contact angle measurements demonstrated that TAA presents the best compatibility in the interface. Solar cells modified with TAA, set up in inverted configuration, showed 0.03% of overall energy conversion efficiency, which is three times larger than the one obtained from a standard device. Replacing TAA by N719 dye on TiO2 surface increased the efficiency, achieving values higher than 1%. Inserting TiO2 rod-shaped nanoparticles (TiO2 NB/TAA) on P3HT layer of the latter system resulted in 1.35% overall efficiency. Photoelectrochemical experiments demonstrated that this modification using TiO2 NB/TAA increases exciton separation rate and conductivity properties slightly enhanced compared to spherical nanoparticles (TiO2 NE/TAA). Small-Angle X-ray Scattering (SAXS) showed that TiO2 NB/TAA and TiO2 NE nanoparticles are homogeneously distributed in the P3HT matrix. In the Si/P3HT hybrid system, the inorganic/organic interface was modified through chemical adsorption of TAA molecules on the native oxide (Si/SiOx/TAA) and a reaction of the surface Si-Cl groups with Grignard reagent 2-thiophene-magnesium bromide (Si/Tiofeno). Both reactions were characterized using Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS). The contribution of P3HT to the p-n junction formation in the photovoltaic device was evaluated from a comparison with a Schottky junction (Al/Si/Au). The VOC values obtained with P3HT were similar among the experiments (around 0.4 V) and higher than without the polymer (around 0.2 V). This observation highlights the dominance of Si/P3HT for photovoltaic properties. The Si/SiOx/TAA device exhibited a high series resistance, with energy conversion efficiency lower than 0.5%. However, using Al/Si/Tiofeno/P3HT/Au configuration, the solar cells reached 5.76% efficiency. The higher values might be related to a better adhesion and compatibility between Si and P3HT, which was observed from SEM images
Doutorado
Quimica Inorganica
Doutor em Ciências

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Leblois, Richard. "Solar Impulse - Around the World in a Solar Airplane." Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-86938.

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- Einführung in das Projekt Solar Impulse (Entstehung, Herausforderung, Errungenschaften) - Beschreibung der eingesetzten Software Tools zur Entwicklung des Flugzeuges - Fallbeispiele für den Einsatz von Mathcad

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42

Nygren, Martin Alexander. "Solar Simulation for the NTNU Test Satellite Solar Cells." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24434.

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The relevant energy theory behind intensity and spectral irradiance from the sun is discussed with regard to how it changes due to factors like Earth-Sun distance, solid angle of the sun disk and circumsolar region, angle of incidence and atmospheric mass. This translates to how the experienced conditions for solar cells vary, how and why solar simulation is done the way it is with such stringent requirements, as well as what can be expected in terms of difference between controlled, fixed conditions and operation in environments where we are not free to modify the variables as easily. The most essential theory of solar cell structure and performance is reviewed, with emphasis on the theory needed to understand the design principles, characteristics and behavior of the high-efficiency multijunction solar cells available for the NUTS project. The most commonly encountered components of a solar simulator is discussed to the point where the information provided should allow for a well-informed evaluation and selection of design for most applications, and be of guidance if one were to wish to attempt to create a device able to simulate aspects of the solar irradiation.Solar cell characteristics are developed by the use of a solar simulator under controlled testing conditions to ensure reproducible results. The effect of controlled sunlight from a range of different angles onto a solar cell is investigated in terms of current-voltage characteristics, and in particular the effect on short circuit current as compared to what is expected of theory. It is found that the angle of incidence of light can be calculated from the measured current with a general accuracy of about 1 degree, when compensating for reflectivity in the solar cell cover glass.

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Bame, Aaron T. "Optimization of Solar-Coal Hybridization for Low Solar Augmentation." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/8942.

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One approach to enabling a larger penetration of renewable sources of energy is the implementation of hybrid power plants. This work presents a process to determine the preliminary optimal configuration of a concentrating solar power-coal hybrid power plant with low solar augmentation, and is demonstrated on a coal power plant in Castle Dale, UT. A representative model is developed and validated against published data for a coal power plant of a different configuration than Hunter Unit 3. The simplifications within the representative model include combining multiple feedwater heaters, combining turbines that operate across the same boundary states, and the mass-average calculation for extraction properties to the combined feedwater heaters. It is shown that the representative model can accurately and consistently simulate a coal power plant. Comparing net power generation and boiler heating estimates from the representative model to the benchmark power plant, the representative model is accurate to within +/- 1% the accepted value from the benchmark power plant. The methods for quantifying solar resource with data from the National Renewable Energy Laboratory are presented with the derivation of an algorithm to simulate a concentrating solar power field arrangement. The solar contribution to electrical power output is estimated using an exergy balance. A simplified financial model is also developed to estimate the solar marginal levelized cost of electricity and payback time using a cash-flow analysis. Estimates for solar resource, solar contribution, and financial performance are consistent with data published by the National Renewable Energy Laboratory or in archival literature. A multi-objective optimization routine is developed consisting of the representative model, the augmentation of solar energy into the solar integration model by means of feedwater heater bypass, solar contribution, levelized cost of electricity, and payback time. Because this study considered complete FWH bypass, higher solar augmentation (>3% of boiler heating) is required for a hybrid design to be considered feasible. However, for higher solar augmentation, the costs are also considerably higher and the financial benefit is insufficient to make any hybrid designs feasible unless a carbon tax is in place. A carbon tax will amplify the financial benefit of hybridization, so optimization results are provided assuming a carbon tax value equivalent to the value used in California's Emissions Trading System (16 USD sh.tn.^-1). The impact of a green energy premium price paid by consumers is also explored in the context of payback time. The resulting optimal design for the Hunter Unit 3 with a carbon tax and no premium is using parabolic trough collector technology at an augment fraction of k=9% to bypass feedwater heater 6. The resulting marginal solar levelized cost of electricity is 9.5 x 10^-4 USD kWh^-1 with an estimated payback time of 25.2 years. This process can be applied to any coal power plant for which operating data and meteorological data are available to evaluate preliminary hybridization feasibility.

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Hassanain, Ahmed A. "Investigation of solar chimneys and tubular transpired solar air heaters as improved systems for solar dryers." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393770.

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Elhabishi, Ali Mohamed. "Optimising collector plate geometry for a specific solar syphon system design." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2385.

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Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2016.
Solar energy is still not being used effectively in countries in the developing world, though it's a partial solution to the problem of shortage and expensive energy. Normally harvested through flat plate collectors, converting solar radiation into heat is the most direct application that can be effected in water heating systems. Many researchers have attempted to develop means of improving the efficiency of the flat plate solar energy collector; however there appears to be no evidence of any work regarding the effect of geometric configuration on the performance of flat plate solar collector. This study presents results obtained when comparing the performance of a solar water heating system equipped with three manufactured flat plate solar collector panels of numerically identical surface area but of different geometric configuration as they were individually attached to a typical geyser. Data was obtained inside a laboratory. The amount of heat acquired from flat plate collectors of solar energy depends primarily on their surface area that is exposed to the solar irradiance, however, the geometry of the collectors was thought that it might affect to some extent the amount of heat harvested. The circulation of the water from the panel to the geyser was due to the self-induced thermo-syphon effect. The results obtained during the test period (7 hours per day for two consecutive days) indicated that the system’s thermal efficiency was best when the square geometrical configuration collector was used. A dimensional analysis using the Π Buckingham method that was performed on the parameters affecting a flat plate solar collector yielded three dimensionless numbers that lead to a power law relationship which might be useful in enhancing solar water heating systems’ design.

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Mattos, Sérgio Ricardo de [UNESP]. "Análise do rendimento térmico do aquecedor solar parabólico cilíndrico." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/99302.

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Made available in DSpace on 2014-06-11T19:30:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-09Bitstream added on 2014-06-13T20:39:45Z : No. of bitstreams: 1 mattos_sr_me_guara.pdf: 1275419 bytes, checksum: 6a6b8796ddc4c875ee2155aa72412e97 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este aquecedor solar foi construído em uma estrutura metálica, que tem um revestimento de polietileno reflexivo parabólico cilíndrico, onde no foco da parábola passa uma serpentina com sete tubos em cobre de 9,5 mm e o projeto foi desenvolvido para obter temperaturas mais elevadas do que os aquecedores planos. O objetivo desta dissertação foi atingir temperaturas mais altas na fase líquida. As temperaturas alcançadas foram obtidas utilizando uma densidade de potência solar que variou entre (1.000±10) W/m2, nas vazões de: 66, 54, 42, 30, 27, 24, 21, 18, 15, 12 e 9 litros por hora. A máxima temperatura atingida utilizando-se a vazão de nove litros por hora foi de 71°C, permitindo uma diferença de temperatura, em relação a temperatura ambiente de 43°C. A máxima vazão utilizada no aquecedor solar parabólico cilíndrico foi de 66 litros por hora e obteve-se uma temperatura de 38°C, sendo a diferença em relação à temperatura ambiente de 6°C. Assim com o desenvolvimento do aquecedor solar parabólico cilíndrico obtiveram-se temperaturas maiores em uma área de captação menor, do que em aquecedor convencionais planos e com rendimentos superiores a 70% em sua maior faixa de operação
This solar heater is constructed of a metallic structure, which has a polyethylene coating reflective parabolic cylindrical, where the focus of the parable is a serpentine seven copper pipes of 9.5 mm and the project was designed to obtain higher temperatures than the heaters plans and the objective of this thesis was to reach higher temperatures in the liquid phase. The temperatures reached were obtained using a solar power density ranged from (1000±10) W/m2, the flow rates: 66, 54, 42, 30, 27, 24, 21, 18, 15, 12 and 9 liters per hour. The maximum temperature reached by using the flow of nine liters per hour was 71°C, allowing a temperature difference in relation to ambient temperature of 43°C. The maximum flow rate used in the cylindrical parabolic solar heater was 66 liters per hour and obtained a temperature of 38°C, and the difference in the ambient temperature of 6°C. So with the development of a cylindrical parabolic solar heater temperatures were obtained in a larger area smaller than in conventional heating plans and with performance up to 70% on the higher range of operation

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Almeida, Carlos Eduardo Freire d’. "Análise comparativa do sistema solar termodinâmico vs. sistema solar térmico." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/21199.

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Mestrado em Sistemas Energéticos Sustentáveis
Com este trabalho pretende-se comparar energética e financeiramente o sistema solar térmico e o sistema solar termodinâmico aplicados para captura de energia solar em sistema de água quente sanitária. Para isso comparou-se, a partir do software Retscreen e EcoREN, o desempenho e performance de cada sistema, que depende em muito da temperatura do ar e da radiação incidente local, para três cidades portuguesas: Bragança, Coimbra e Faro. Daí foi possível percecionar o fluxo de caixa anual de cada sistema solar em relação a um sistema de referência (termoacumulador elétrico), e obtiveram-se os dados financeiros que demonstram a viabilidade de cada projeto e auxiliam na escolha do sistema solar mais adequado a implementar em cada uma das cidades referenciadas. Os resultados obtidos indicam que o sistema solar térmico está mais dependente da radiação, e, portanto, tem maior oscilação da fração solar ao longo do ano, e do local (Bragança 55 %, Coimbra 61 % e Faro 68 %). Já no sistema solar termodinâmico, a fração solar obtida é relativamente constante, mantendo-se a cerca de 65%, independentemente da localização, sendo compensado por um maior trabalho e consumo elétrico por parte do compressor em períodos de menor eficiência térmica. Em termos financeiros o sistema solar térmico apresentou payback inferior para Coimbra e Faro, tal como um maior fluxo de caixa, pois o sistema solar termodinâmico tem custos extra associados ao compressor.
The aim of this work is to make an energy and financial comparison between a solar thermal system and a thermodynamic solar system, when applied as a domestic hot water heater. With the support of Retscreen and EcoREN software, was modeled the performance of each system, which are mainly affected by air temperature and incident solar radiation. The study was conducted for three portuguese cities: Bragança, Coimbra and Faro. Therefore, it was possible to compare the cashflow of different systems relative to a reference technology (electric thermal accumulator). The financial data in particular was key in determining the viability of each solar system and may work as a support in the decision making for the most suitable solar system which should be implemented in each of the studied cities. The obtained results show that the solar thermal system is more dependent of the radiation, therefore there is a major swing of the solar fraction throughout the year, and the location (Bragança 55 %, Coimbra, 61 % and Faro 68 %). As for the thermodynamic solar system, the solar fraction is relatively constant, around 65 %, no matter the location, although more work is required from the compressor. As for the financial aspect, with the solar thermal system the payback is lower for Coimbra and Faro, and also have higher cashflow, because the thermodynamic solar system has extra costs with the compressor

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48

Montornès, Torrecillas Alex. "A study of the shortwave schemes in the Weather Research and Forecasting model." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/401501.

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The radiative transfer cannot be explicitly resolved in the atmospheric models for two reasons: i) a full treatment of the radiative transfer equation (RTE) requires a high amount of computational resources and ii) the radiative transfer fields such as the optical thickness are not a direct solution of the Euler equations and hence, they must be parameterized as a function of the meteorological fields. Consequently, the physical processes related with radiation are simplified and approximated in physical schemes. In the particular case of the solar radiation, the use of these parameterizations were reduced for many years to represent the day/night cycle inside the model. Therefore, the accuracy of the solar schemes was left in the background and the computational resources were prioritized. With the growth of the solar energy industry during the last decade, a paradigm shift has occurred. Now, the solar irradiance (i.e. global horizontal GHI, direct horizontal DHI and diffuse DIF) becomes an important product for resource assessment as well as for forecasting applications. The main objective of this thesis is the identification and quantification of the sources of error that have a direct or an indirect contribution to the accuracy of the solar schemes, particularly, in those available in the Weather Research and Forecasting (WRF-ARW) model, widely used in the sector. First, the thesis presents a review of the set of physical approximations considered in six solar parameterizations available in the WRF-ARW model: Dudhia, Goddard, New Goddard, Rapid Radiative Transfer Model for General Circulation Models (RRTMG), Climate Atmospheric Model (CAM) and Fu-Liou-Gu (FLG). The sources of error are limitations in the representation of the radiative transfer as a conse- quence of the set of approximations assumed by one scheme. In this thesis three sources of error are analyzed: i) errors due to the vertical discretization of the atmosphere in a set of layers that are assumed to be homogeneous (truncation error), ii) errors due to the misrepresentation of the layer between the top of the model (TOM) and the top of the atmosphere (TOA), called TOM error and iii) errors due to the physical simplifications and parameterizations in the RTE, named physical error. In order to avoid the uncertainty introduced by the other components of the model, the source code of each one of the six solar schemes has been separated of the model and adapted for working with 1-dimensional vertical profiles. The studies of the truncation and TOM errors are performed by using ideal vertical profiles under four scenarios: a dry atmosphere, a wet cloudless sky, low water cloud and a high ice cloud. The results for the ETOM show that for the typical range of TOM values in mesoscale appli- cations (i.e. 10 hPa), the error with respect to a full atmospheric column is less than 0.5% and hence, the TOM error can be neglected. The analysis of the Etrun reveals that the sensitivity of the solar schemes on the vertical config- uration (i.e. number of vertical levels and their distribution) is directly related with the method used for the vertical integration of the multiscattering processes. For the typical mesoscale config- urations, the Etrun under clear-sky conditions is determined around 1.1%, 0.9% and 4.9% for the GHI, DHI and DIF, respectively. In both cloudy scenarios, the Etrun increases significantly, being more important for the high clouds. The Ephys is analyzed under clear-sky conditions using real soundings from the Integrated Global Radiosonde Archive data-set and comparing the irradiance outcomes with the Baseline Solar Radiation Network measurements. With the exception of Dudhia, the behavior for all the parameterizations is the same. A large overestimation of the DHI with a large underestimation of the DIF that leads to a near-zero bias for the GHI. Polar sites show the lowest errors with a mean MAE of 2.1%, 5.2% and 3.7% for GHI, DHI and DIF, respectively. Midlatitude sites show the worst results with a mean MAE of 3.4% in GHI, 11.6% in DHI and 7.8% in the DIF.
L’objectiu principal d’aquesta tesi ´es la identificaci´o i quantificaci´o de les fonts d’error que tenen una contribuci´o directa o indirecta en la precisi´o dels esquemes solars, particularment en aquells disponibles en el model Weather Research and Forecasting (WRF-ARW), `ampliament emprat en el sector de l’energia solar. Les fonts d’error s´on limitacions en la representaci´o del transport radiatiu com a consequ¨`encia del conjunt d’aproximacions assumides per cada esquema. En aquesta tesi hi ha tres fonts d’error que s´on analitzades: i) l’error degut a la discretitzaci´o vertical de l’atmosfera en un conjunt d’estrats que s’assumeixen homogenis (error de truncament, Etrun), ii) l’error com a resultat d’una repre- sentaci´o insuficient de l’estrat entre el cim del model (TOM) i el cim de l’atmosfera (TOA), anomenat error de TOM Etom, i iii) l’error degut a les simplificacions i a les parametritzacions f´ısiques de l’RTE, definit com a error físic, Ephys. Per tal d’evitar la incertesa introdu¨ıda pels altres components del model, el codi font de cadas- cun dels sis esquemes solars ha estat separat del model i adaptat per treballar amb perfils verticals 1-dimensionals. Mitjan¸cant aquest m`etode, les habilitats dels esquemes solars poden ´esser anal- itzades sota condicions d’entrada id`entiques. D’una banda l’error de TOM i el de truncament s’analitzen a partir de perfils ideals. De l’altra, l’error f´ısic s’evalua prenent dades de radiosondatge com a perfil vertical i comparant les sortides dels esquemes radiatius amb mesures en superf´ıcie. Els resultats d’aquesta tesi mostren que l’Etom esdev´e negligible per la majoria d’aplicacions de mesoscala. Per configuracions t´ıpiques del model, l’Etrun en condicions de cel ser`e es troba al voltant de l’1.1%, el 0.9% i el 4.9% per la GHI, DHI i DIF, respectivament. En el cas amb nu´vols augmenta de forma significativa. L’estudi de l’Ephys mostra una relaci´o significativa amb el contingut de vapor d’aigua i els aerosols.

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Escobedo, João Francisco. "Refrigeração com uso de energia solar." Universidade de São Paulo, 1987. http://www.teses.usp.br/teses/disponiveis/54/54132/tde-28052009-094024/.

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Uma simulação numérica do ciclo de refrigeração a adsorção é realizada para os pares zeólita-água e carvão ativo AC-35 metanol, justificando a escolha do par bem como do sistema de captação a serem utilizados no protótipo. O protótipo construído compreende um concentrador cilíndrico-parabólico com rastreamento solar, um tubo de calor e uma unidade frigorífica (com zeólita-água). Aspectos tecnológicos como válvulas, soldas e carregamento do par na máquina são analisados. Os resultados dos testes de desempenho são apresentados, discutidos e comparados com a literatura. Uma análise de custos é feita. Paralelamente, construímos termo pilhas pelo método da evaporação. Estas termopilhas foram utilizadas na construção do piranômetro e do pireliômetro. Os instrumentos são caracterizados em termos de sensibilidade, constante de tempo, linearidade, efeitos de temperatura e convecção natural. Os resultados desta caracterização são discutidos e comparados com um modelo fabricado pela Eppley. Finalmente, no apêndice I, testamos o desempenho de um coletor plano utilizando no absorvedor o revestimento seletivo de óxido de alumínio recentemente desenvolvido no IFQSC. As melhores condições para obtenção do revestimento seletivo em placas de grande porte são estudadas.
A numerical simulation of the adsorption refrigeration cycle was made for zeolite/water and activated carbon(AC-35)/ methanol pairs, to select the pair and the solar collector in the prototype. The fabricated prototype consists of a cylindrical paraolic concentrator with solar trackins, a heat pipe and the refrigeration unit (with the zeolite/water pair). The technical aspects of values, welds and out-gassing are analyzed. The results of the performance tests are presented, discussed and compared with the literature. An analysis of costs is made. In parallel thermopiles were constructed using the evaporation method. These thermopiles were used in the construction of the piranometer and the pirheliometer. The instruments were characterized in terms of: sensitivity, stability with time, linearity, effects of temperature and natural convenction. The results of this characterization are discussed and compared with a model made by Eppley. Finally, in Apendix I, we tested the performance of a flat plate collector using a selective coating of aluminium oxide (developed in IFQSC) as absorber. The Best conditions for obtaining the seletive coating on big size plates are discussed.

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Claudino, Filho Vicente de Vasconcelos. "Desenvolvimento de um coletor Fresnel para sistema de climatização dessecante." Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/8678.

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Brazil has as a main source for production of electricity the dams using water to drive the turbines and as a secondary source are used the thermoelectric power plants that use fuel oil for electric power production. Both generate a large environmental impact, due to the fact of the dams need huge areas for its construction, which often leads to destruction of important ecosystems in the region where it will be installed the hydroelectric plant, besides the fact that they need the rainfall cycle so that the dams have the operating capacity, while the thermoelectric power plants burn fossil fuels thus increasing emissions of CO2 to the atmosphere. An alternative to the solution of the problems mentioned above is the use of renewable sources of energy, with emphasis on this work. Solar energy can be divided into two parts: thermal and photovoltaic. This work it is focused on thermal use of solar energy, with a Fresnel-type solar concentrator to heat water, which will trigger a cooling system environment with the use of desiccant rotors. The choice of type Fresnel collector gave the field of development of this hub is still in constant growth and by the fact that even occupy a relatively small area when compared to other solar thermal concentrators, in addition to its construction be simple and low cost when again compared to other solar concentrators.
O Brasil tem como fonte principal para produção de energia elétrica as hidrelétricas que utilizam água para movimentar as turbinas e como fonte complementar são utilizadas as termoelétricas que usam óleo combustível para produção de energia elétrica. Ambas geram um grande impacto ambiental, devido ao fato das hidrelétricas necessitarem de enormes áreas para a construção das represas, o que muitas vezes acarreta na destruição de ecossistemas importantes para a região onde irá ser instalada a hidrelétrica, além do fato que elas necessitam do ciclo das chuvas para que as represas possuam capacidade de operação, enquanto que as termoelétricas queimam combustíveis fosseis, aumentando assim as emissões de CO2 para a atmosfera. Uma alternativa para a solução dos problemas citados anteriormente é a utilização de fontes renováveis de energia, dando ênfase neste trabalho a energia solar. A energia solar pode ser dividida em duas vertentes: térmica e fotovoltaica. Este trabalho está voltado para a utilização térmica da energia solar, através da utilização de um concentrador solar do tipo Fresnel para o aquecimento de água, a qual irá acionar um sistema de refrigeração de ambientes com a utilização de rotores dessecantes. A escolha do coletor do tipo Fresnel se deu pelo campo de desenvolvimento deste concentrador estar ainda em constante crescimento e pelo fato do mesmo ocupar uma área relativamente pequena quando comparado com outros concentradores solares térmicos, além de sua construção ser simples e de baixo custo quando novamente comparada a outros concentradores solares.

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