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Building integrated wind energyWang, Jialin January 2013 (has links)
In considering methods of reducing the emission of carbon dioxide; there is a growing interest for use of wind power at domestic building in U.K. But the technology of wind turbines development in building environment is more complicated than in open areas. Small wind turbines in suburban areas have been reported as having unsatisfactory energy output, but it is not clear whether this is due to insufficient wind resource or low turbine efficiency. The aim of this research is to discover whether the wind resource in suburban areas is large enough for small wind turbines to produce a useful energy output.Historical wind data and manufacturers' turbine characteristics were used to estimate the hourly wind speed and energy output for different U.K. cities, terrain zones and turbines. It was found that for turbines at 10 m height in suburban areas and depending on city, the annual wind energy conversion efficiency ranged from about 20 to 40%, while the number of turbines required to produce the annual average electricity consumption of a UK dwelling ranged from about 6 for the smallest turbine (5.3 m² rotor area) to about 1 for the largest (35.26 m² rotor area).This analysis was based on average conditions, but the wind speed near buildings can vary considerably from one point to another. In order to predict the performance of wind turbines more accurately, the atmospheric boundary layer (ABL) of suburban areas was simulated in both CFD and wind tunnel models, and models of groups of semi-detached and terraced houses were set in this ABL. It was found that at 10 m height in the area of the houses, the turbulence intensity was too high for satisfactory operation of wind turbines (19 to 35%) while the mean velocity at different points ranged from 86 to 108% of the 10m reference velocity. At 30m height the turbulence intensity was satisfactory (less than 19 %), while the mean velocity ranged from 92 to 103 % of the 30 m reference velocity. It is concluded that for wind turbines in suburban areas, at 10 m height the wind speed is too low and the turbulence is too high for satisfactory performance, while at 30 m height the wind speed is much higher and the turbulence is low enough.
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Andante, caminhante, passante, pedestre: ensaio fotográfico de passageiros urbanosRodrigues, Miguel Etges 26 October 2009 (has links)
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Previous issue date: 2009-10-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The urban projetcts for large urban centers at the end of the nineteenth century and beginning of XX conditioned new ways for the occupation of urban space for its inhabitants. This work aims to conduct a photographic study of the flow of pedestrian in the urban area selected for this work ñ the crosswalk towards to Urban Transport Terminal (TICEN) or to
downtown of Florianopolis city. For this, we used the multiple exposures of photographic sequence aesthetic as an analogy to blots that was used as a pictorial representation of the human figure by the impressionist school of painting. With this technique, the artists began a possible process to reveal the erasement of the human figure in the presence of the proportions of the new configurations for urban space. The photographic sequences, presented in this work, have as aim to represent, in a contemporary way, this erasement
of the pedestrian into the selected area of the city through the transparency generated by the sequence of photographic frames superimposed. This superimposition of images also suggests the overlapping of realities and impact of individuals in the photography time. After make reference to the
Impressionist artists, I use other artists that take advantage of the pictorial or photografic method to represent the urban space. Therefore their works helped in the broand of the perception and construction to make photo about the pedestrian flow on the tangle of city roads. The present study is divided into three chapters, the first one has the city as its main topic, exposing the urban planning from the middle of nineteenth century and beginning of XX, in Europe, through its applications in Brazil until to reach at the Florianopolis
city. The second chapter is concerned about the representing art of the city from the impressionist school of painters as well as some artists works that use the sequential photography to express their urban spaces representations. The third chapter presents the photographic series produced in the study area. We can see, on them, the superposition of
the photographic frames, the pedestrian movement, the change of time and convergence of different realities in the images transparence / Os projetos de urbanização dos grandes centros urbanos do fim do século XIX e início do XX condicionaram novas maneiras de ocupação do espaço urbano para seus habitantes. Com isso, o presente trabalho tem como objetivo realizar um estudo fotográfico do fluxo de transeuntes no espaço urbano selecionado para esse trabalho a faixa de segurança para pedestres em direção ao Terminal de Transporte Urbano - TICEN ou ao centro da cidade de Florianópolis. Para isso, utilizou-se a estética de sequência
fotográfica de múltiplas exposições em analogia aos
borrões pictóricos utilizados como representação da
figura humana pela escola de pintura impressionista.
Com essa técnica de pintura, os artistas iniciam um possível processo de denúncia do apagamento da figura humana perante as proporções das novas configurações do espaço urbano. As sequências fotográficas, apresentadas nesse trabalho, possuem o propósito de representar de maneira contemporânea esse apagamento do transeunte no espaço selecionado da cidade através da transparência produzida
pelas sequências de quadros fotográficos justapostos.
Essa justaposição de imagens também sugere a sobreposição de realidades e o choque de indivíduos no tempo fotográfico. Após referenciar os artistas impressionistas utilizo outros artistas que lançam mão do método pictórico ou fotográfico para representar o espaço urbano. Visto que suas obras auxiliaram na ampliação da percepção e construção do fazer fotográfico sobre os fluxos de pedestres do emaranhado
de vias da cidade. Esse trabalho divide-se em três capítulos, o primeiro tem a cidade como assunto principal expondo
os planejamentos urbanos de meados do século XIX
e início do XX, na Europa, passando por suas aplicações
no Brasil até chegar à cidade de Florianópolis. O segundo capítulo trata da arte de representação da cidade a partir dos pintores da escola impressionista bem como algumas obras de artista que utilizam a fotografia sequencial para expressar as suas representações dos espaços urbanos. No terceiro capítulo apresento as séries fotográficas produzidas no
espaço de estudo. Nelas podemos visualizar a justaposição
de quadros fotográficos, o deslocamento dos pedestres, a variação do tempo e a convergência de distintas realidades nas transparências das imagens
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Etude de l'impact des incertitudes dans l'évaluation du risque NRBC provoqué en zone urbaine / A study on the impact of uncertainties in the risk assessment of CBRN scenarios in urban areasMargheri, Luca 13 November 2015 (has links)
La dispersion d'agents biologiques hautement pathogène dans une zone urbanisée après un acte terroriste est l'une des situations que les agences de sécurité nationales ont besoin d'évaluer en termes des risques et de la prise de décision. La simulation numérique des écoulements turbulents dans les zones urbaines, y compris la surveillance de la dispersion des polluants, a atteint un niveau de maturité suffisant pour faire des prédictions sur les zones urbaines réalistes jusqu'à 4 km2. Les simulations existantes sont déterministes dans le sens que tous les paramètres qui définissent le cas étudié (l'intensité et la direction du vent, la stratification atmosphérique, l'emplacement de la source des émissions, etc.) devraient être bien connu. Cette précision ne peut être atteint dans la pratique en raison d'un manque de connaissances sur la source d'émissions et de l'incertitude aléatoire intrinsèque des conditions météorologiques.Pour augmenter la contribution de la simulation numérique pour l'évaluation des risques et la prise de décision, il est essentiel de mesurer quantitativement l'impact d'un manque de connaissances en termes de résolution spatiale et temporelle des zones de danger.L'objet de cette thèse est d'appliquer des méthodes de quantification d'incertitude pour quantifier l'impact de ces incertitudes dans l'évaluation des zones de danger à moyenne portée dans des scénarios de dispersion de gaz toxiques. Une méthode hybride c-ANOVA et POD/Krigeage permet d'envisager jusqu'à 5 paramètres incertains dans une simulation 3D-CFD haute fidélité non-stationnaire de la dispersion d'un gaz toxique provenant d'une source type flaque dans une zone urbaine de 1km2. / The dispersion of highly pathogenic biological agents in an urbanized area following a terrorist act is one of the situations that national security agencies need to evaluate in terms of risk assessment and decision-making. The numerical simulation of turbulent flows in urban areas, including monitoring the dispersion of pollutants, has reached a sufficient level of maturity to make predictions on realistic urban zones up to 4 square kilometers. However, the existing simulations are deterministic in the sense that all the parameters that define the case studied (intensity and wind direction, atmospheric stratification, source of emissions location, quantity of injected toxic agent, etc.) should be well known. Such precision cannot be achieved in practice due to a lack of knowledge about the source of emission and the intrinsic aleatoric uncertainty of the meteorological conditions. To significantly increase the contribution of numerical simulation for risk assessment and decision-making, it is essential to quantitatively measure the impact of a lack of knowledge especially in terms of spatial and temporal resolution of the danger zones. The object of this thesis is to apply uncertainty quantification methods to quantify the impact of these uncertainties in the evaluation of the danger zones in medium range toxic gas dispersion scenarios. A hybrid method merging c-ANOVA and POD/Kriging allows to consider up to 5 uncertain parameters in a high-fidelity unsteady 3D-CFD simulation of the dispersion of a toxic gas from a pond-like source in an urban area of 1km2.
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Best way to go? Intriguing citizens to investigate what is behind smart city technologiesTachtler, Franziska Maria January 2016 (has links)
The topic of smart cities is growing in importance. However, a field study in the city of Malmö, Sweden shows that there is a discrepancy between the ongoing activities of urban planners and companies using analytical and digital tools to interpret humans’ behavior and preferences on the one hand, and the visibility of these developments in public spaces on the other. Citizens are affected by the invisible data and software not only when they use an application, but also when their living space is transformed. By Research through Design, this thesis examines ways of triggering discussion about smart city issues, which are hidden in software and code. In this thesis, a specific solution is developed: a public, tangible, and interactive visualization in the form of an interactive signpost. The final, partly functioning prototype is mountable in public places and points in the direction of the most beautiful walking path. The design refers to a smart city application that analyzes geo-tagged locative media and thereby predicts the beauty and security of a place.The aim is to trigger discussion about the contradictory issue of software interpreting the beauty of a place. Through its tangible, non-digital, and temporary character, the interactive representation encourages passers-by to interact with the prototype.
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