Le décalage vers le rouge est la principale mesure par laquelle les astronomes peuvent cartographier l’Univers dans la direction radiale. Afin de tester les hypothèses d’homogénéité et d’isotropie, il est nécessaire de mesurer avec precision le décalage vers le rouge d’un grand nombre de galaxies. De plus, différents modèles cosmologiques ne peuvent être distingués qu’au travers d’une analyse précise des structures à grandes échelles tracées par ces galaxies. Pour obtenir un grand nombre de ces mesures, il est nécessaire de mener d'importantes campagnes d’observations pour établir des relevés couvrant une large portion du ciel. Ces mesures trouvent aussi d’autres applications en astronomie comme par exemple l’analyse du cisaillement gravitationnel, la calibration des mesures photométriques, l’étude des halos de matière noire, de la morphologie des galaxies, des structures à grandes échelles et de la distribution des galaxies.Dans tous les relevés de galaxies, les mesures les plus problématiques sont pour les objets de plus faible luminosité, où le bruit instrumental devient gênant, et qui se trouvent être en général les objets les plus lointains. Pour ces objets, les mesures de décalages vers le rouge peuvent souvent devenir imprécise et, la plupart du temps, elles sont simplement exclues de l’analyse en appliquant des coupures en magnitudes ou en rapport signal à bruit. Cette procédure est une méthode brutale pour séparer les mesures probablement imprécises des mesures fiables.Dans cette thèse, nous développons un algorithme permettant la mesure du décalage vers le rouge des spectres de galaxies dans le regime de faible rapport signal à bruit. La première partie de cette thèse présente les différents concepts relatifs à l’estimation du décalage vers le rouge et au débruitrage de signaux par transformation en ondelettes et filtrage par taux de fausse détection (False Detection Rate, FDR en anglais). La seconde partie détaille comment ces concepts sont mis à contribution dans l’élaboration de l’algorithme Darth Fader (Denoised and Automatic Redshifts THresholded with a False DEtection Rate). Enfin, la dernière partie présente l’application de cet algorithme à des données synthétiques générées à partir du COSMOS Mock Catalogue, mais aussi sur des données réelles tirées du relevé WiggleZ.Nous montrons que Darth Fader fonctionne efficacement à bas rapport signal à bruit étant donné un choix approprié du taux de fausse détection et d’un critère de comptage de traits caractéristiques judicieux. Nous montrons aussi que Darth Fader permet d’éliminer le continuum des spectres à bas rapport signal à bruit, ce qui rend possible l’estimation du décalage vers le rouge par corrélation croisée. Enfin, nous montrons sur des spectres de test issues du relevé WiggleZ que notre algorithme est capable d’analyser une part importante du relevé de façon autonome avec une haute précision, sans nécessiter d'inspection visuelle (alors que les données WiggleZ ont à l’origine été entièrement soumises à l’inspection visuelle). En conclusion, Darth Fader est un algorithme prometteur pour l’analyse des grands relevés de galaxies, en particulier pour exploiter les objets à faible rapport signal à bruit qui sont habituellement simplement ignorés. / Summary: Redshift is the primary measure by which astronomers can map the Universe in the radial direction. In order to test the assumptions of homogeneity and isotropy, accurate redshifts of galaxies are needed, and for a great many of them. Additionally different cosmological models can only be distinguished by careful observations of the large scale structure traced by these galaxies. Large sky surveys are the only mechanism by which redshifts for a large number of galaxies can be obtained. Accurate redshift estimation is additionally required for many other fields of astronomy including but not limited to: weak lensing, studies of dark matter haloes, galaxy morphology studies, chemical evolution studies, photometric calibration, and studies of large scale structure and galaxy clustering.Problems exist in all surveys at the dim limit of observation, which usually corresponds to the higher redshift objects in the survey, where noise becomes problematic. Magnitude or signal-to-noise ratio cuts are often employed in order to eliminate potentially troublesome objects; such a procedure is a blunt tool for separating good redshift candidates from ones likely to be inaccurate.In this thesis we develop an algorithm to tackle redshift estimation of galaxy spectra in the low signal-to-noise regime. The first part of this thesis introduces the concepts of denoising, particularly False Detection Rate denoising, wavelet transforms and redshift estimation algorithms. The second part details how these concepts are united into the Darth Fader (Denoised and Automatic Redshifts THresholded with a FAlse DEtection Rate) algorithm. The final parts of this thesis apply the algorithm both to idealised synthetic data generated from the COSMOS Mock Catalogue, and to a subset of real data from the WiggleZ survey.We show that Darth Fader can operate effectively at low signal-to-noise given an appropriate choice of FDR parameter for denoising, and an appropriate feature-counting criterion. We also show that Darth Fader can remove the continua of spectra effectively at low signal-to-noise for the purposes of redshift estimation by cross-correlation. Additionally we show from tests on spectra from the WiggleZ survey that our algorithm has the ability to process a substantial subset of that data without the need for visual inspection (to which the entire WiggleZ spectral survey has been subjected), and to a high degree of accuracy. We conclude that the Darth Fader algorithm has potential to be used in large-sky survey pipelines, particularly where signal-to-noise is expected to be poor.

Orientadores: Paulo Sergio Scarazzato, Hélio Pedrini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-26T13:49:42Z (GMT). No. of bitstreams: 1 Souza_DennisFloresde_D.pdf: 57790978 bytes, checksum: b6823404106d40d260ee7c43d24ecaa9 (MD5) Previous issue date: 2014 / Resumo: O uso de imagens de grande alcance dinâmico (HDR) nos estudos de iluminação vem se tornando um expediente frequente pela capacidade de armazenamento de dados referentes à distribuição de luminâncias em uma cena. Diversos estudos comprovaram, por exemplo, as possibilidades de registro da luz natural por imagens digitais, uma vez que as características das imagens HDR puderam melhorar os resultados. Dentre as diferentes aplicações, o registro da abóbada celeste é um dos que mais pode se beneficiar dessa ferramenta, pois tal procedimento é mais simples do que aqueles realizados a partir de medições feitas por luminancímetros ou escâneres de céu. Além disso, atualmente a identificação dos tipos de céu ainda é feita em sua maioria utilizando métodos subjetivos. Isto se deve ao fato de não existir uma metodologia para comparar imagens HDR com modelos matemáticos, apenas métodos unidimensionais que focalizam um ou outro aspecto. Esta pesquisa teve por objetivo desenvolver um método multidimensional de identificação, classificação e extração de dados de iluminação natural a partir de imagens HDR da abóbada celeste. As imagens das câmeras foram calibradas segundo métodos disponíveis para estabelecer a confiabilidade da análise e interpretação dos dados, e foram obtidas em localidade com o mínimo de obstrução à visão da abóbada celeste. O método multidimensional de análise foi desenvolvido juntamente a uma rotina em MATLAB, que serviu ao propósito de verificar sua viabilidade e a precisão. Os dados extraídos foram testados na plataforma Flash, usando a linguagem ActionScript 3, para brevemente demonstrar as possibilidades de uso. Este método utiliza um sistema de classificação baseado na relevância das características identificadas na imagem, como a cobertura de nuvens e a distribuição de luminâncias, para escolher o tipo de céu da norma ISO 15469:2004 (e) / CIE S 011/E:2003 mais apropriado. Os resultados apontam para a viabilidade desse método em escolher o tipo de céu mais relevante de acordo com os dados extraídos da imagem HDR. A proposição deste método multidimensional de análise pode contribuir para a criação de um sistema de classificação e de um banco de dados digital úteis para futuros programas de simulação, providenciando dados de entrada obtidos a partir de medições de uma realidade física, facilmente registrada com precisão e confiabilidade a partir de imagens fotográficas / Abstract: Lately, the high dynamic range images (HDR) have experienced a significant growth in their usage in lighting studies, due to their capacity to store data of luminance distribution in a scene. Various studies have attested, for instance, the possibilities of using digital images in the register of daylighting, since the features of HDR images could enhance the results. Among different applications, the record of the light on the sky vault is one that can benefit most from HDR techniques, because this procedure is simpler than those performed by luminance meters or sky scanners measurements. Besides, the identification and classification of sky types are still done mostly by subjective methods. This can be explained by the unavailability of a methodology able to compare HDR images with mathematical models, although there are unidimensional methods that focus on one or another aspect of digital images. This research aimed at the development of a multidimensional method of identification, classification and extraction of daylight data from HDR images of the sky vault. The images registered by the camera were calibrated using available methods to establish the reliability of the analysis and interpretation of data. They were then obtained on a site with minimal obstruction to the vision of the sky vault. The multidimensional analysis method was developed in conjunction with a routine in MATLAB, which served the purpose of verifying its feasibility and accuracy. The extracted data were tested in Flash platform using ActionScript 3 language to briefly demonstrate the usage possibilities. This method relies on a classification system based on the relevance of the features identified in the image, such as cloud covering and luminance distribution, to choose the most appropriate sky type according to ISO 15469:2004 (e) / CIE S 011/E:2003 Standard. The results demonstrate the feasibility of this method in choosing the most relevant sky type according to the data extracted from the HDR image. The proposition of this multidimensional analysis method may contribute to the creation of a classification system and a digital database useful for future simulation software, providing input data from measurements of a physical reality, easily recorded with accuracy and confidence by photographic images / Doutorado / Arquitetura, Tecnologia e Cidade / Doutor em Arquitetura, Tecnologia e Cidade

This essay analyses how social interactions influence Rachel’s racial identity development using social psychology as the theoretical approach. It also discusses how a main part of racial identity development, racial identity invalidation, which is proven to cause chronic mental health issues in multiracial individuals, is what allows Rachel to explore her black ancestry and culture.

The PhD thesis deals with the theoretical evaluation of the potential use of night cooling techniques in condition of the Czech Republic. Mainly aims to evaluate the potential of night cooling, which uses the physical phenomenon of radiation against the night sky. This technique is widely used mainly in the dry and hot regions where there are the most suitable climatic conditions for this cooling method. The work is based on the current state of knowledge in the area of passive and low-energy cooling systems. These knowledges are applied to the conditions of Czech Republic and by using simulations of the energy, behaviour of the buildings explores the benefits in terms of improving of the internal microclimate and from the perspective of economy operation of conventional cooling equipment. In order to establish the benefits of night cooling on the operation of the building in the dynamically changing conditions, the modular simulation program TRNSYS was used, which is suitable for the analysis of energy systems of buildings and their behaviour. The results of simulation results were converted to thermal comfort parameters of the PMV and the PPD.

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This project is about how we can create architecture that hold the same atmospheric qualities as a tale. By using different media like film, dioramas and technology the tales have been analysed for qualities that have been carried through into architecture. The blend of the real and the unreal is central to any tale and so also to my project; this mixed expression is carried through into the resulting structure. The final product becomes a bath house full of expression, impressions and varying realities.

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holiness and other hauntings is a poetry collection that seeks to understand other people. Armstrong uses her poems to track herself back through time to her cousins, her parents, her grandparents, her teachers, and friends. Her work explores queerness and Catholicism, family fraught and family found, love and grief and guilt and ghosts. Her poems lean towards music; internal rhyme, assonance and consonance, alliteration, and long strings of rhymed vowels that sit like pearls in the mouth. Her poems beg forgiveness in shouts; she writes as remembrance, as prayer, as missive, as an engine for hope. / Master of Fine Arts / holiness and other hauntings is a poetry collection.

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