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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
471

Physiological Effects of Disorientation in Loggerhead (Caretta caretta) and Green (Chelonia mydas) Sea Turtle Hatchlings

Unknown Date (has links)
Following nest emergence, sea turtle hatchling dispersal can be disrupted by artificial light or skyglow from urban areas. Mis- or disorientation increases exposure to predation, thermal stress, and dehydration, could consume valuable energy, and thus influence the likelihood of survival. This study utilized laboratory simulations of extended crawl distances and field observations to investigate the energy cost of disorientation crawling on loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtle hatchlings and the impact on the subsequent swim frenzy. Extended crawls increased oxygen consumption, decreased plasma glucose, and reduced green hatchling swim performance following a 200m crawl. Surprisingly, plasma lactate concentrations did not increase with crawl distance, likely due to frequent rest periods that would, however, increase time on the beach and thus exposure to predators. This research may provide managers with physiological data to determine best practices for sea turtle conservation and adds to the biological knowledge of these animals. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
472

Iluminação natural como fator de qualidade : uma abordagem perceptiva em três habitações de interesse social contemporâneas na cidade de São Paulo/SP/Brasil

Feliciano, Camila Caetano January 2018 (has links)
Avaliar qualidade em iluminação na arquitetura tem sido um tema bastante discutido nas últimas décadas. No entanto, ainda se apresenta de difícil compreensão, devido as várias dimensões que podem envolver uma avaliação de qualidade. A presente dissertação se propõe ao estudo da qualidade de iluminação natural dos ambientes, a partir da análise da percepção dos usuários, ou seja, colocando o usuário no centro do projeto. Em paralelo pretende-se também avaliar o grau de satisfação dos mesmos com relação à iluminação dos ambientes e as influências na percepção das dimensões: aconchego, vivacidade e tensão. Foram estudadas as salas de estar e corredores de acesso em apartamentos de três conjuntos habitacionais de interesse social edificadas na última década e localizados na cidade de São Paulo, SP, Brasil. Nas análises das habitações foram realizados levantamentos de iluminância e posteriormente o cálculo do Daylight Factor (Fator de Luz do dia) dos ambientes e aplicados questionários de avaliação de percepção da atmosfera e qualidade da iluminação. Os questionários foram desenvolvidos com base nas metodologias Atmosphere Metrics (Vogels, 2008) e ELI - Ergonomic Lighting Indicator (Indicador Ergônomico de Iluminação) (Dehoff, 2010). Os resultados apontaram diferentes percepções de qualidade entre os conjuntos, comprovando que a avaliação desse fator está sujeita às questões além do atendimento de valores de iluminância estabelecidos pelas tarefas visuais dos ambientes. O estudo também indicou uma forte relação da percepção da atmosfera e da qualidade do ambiente com a tipologia das janelas. / Evaluating quality of lighting in architecture has been a topic widely discussed in recent decades. However, it is still difficult to understand it due to the various dimensions that an evaluation of quality may involve. This dissertation aims at the study of natural lighting as a factor of quality of an environment, based on the user's perception analysis, that is, putting the user in the center of the project. At the same time, it is also intended to evaluate the degree of user satisfaction with regard to the illumination of the studied environments and the influences on the perception of the dimensions of pleasantness, vitality, and environmental tension. Living rooms and the access corridors were studied in apartments of three social housing built in the last decade and located in the city of São Paulo, SP, Brazil. In the analysis of the residences, illuminance surveys and subsequently the calculation of the Daylight Factor of the environments and the application of questionnaires to evaluate the perception of the atmosphere and the quality of the lighting were carried out. The applied questionnaires were developed based on the Atmospheric Metrics and ELI - Ergonomic Lighting Indicator methodologies. The final results presented did not identify similar quality responses along the sets, proving that the quality evaluation is subject to questions beyond the fulfillment of the illuminance values established by the functions of the environments. As a final result, there was also a strong relation between the perception of the atmosphere and the quality of the environment with the typology of the frames.
473

Desenvolvimento de queimadores para iluminação a gás à base de silicato de terras raras / Development of rare earth silicate burners for gas lighting

Silas Cardoso dos Santos 01 August 2014 (has links)
O dissilicato de ítrio (Y2Si2O7) por apresentar propriedades luminescentes consideráveis, é um potencial substituto dos óxidos de terras raras na tecnologia de queimadores de gás para iluminação. Em processos de conformação a partir de suspensões, o controle da estabilidade das partículas em meio líquido consiste em uma importante etapa para a produção de componentes com microestrutura homogênea e estabilidade estrutural. Neste sentido, este trabalho apresenta estudos sobre o comportamento de superfície, de estabilidade e reológico de suspensões aquosas de Y2Si2O7 e β-Y1,95Dy0,05Si2O7 com o objetivo de preparar suspensões compatíveis para o processo de conformação por réplica, usando-se fibras vegetais como matriz para a confecção de componentes reticulados para queimadores de gás. Neste estudo foram avaliados parâmetros determinantes na estabilidade e comportamento de fluxo das suspensões, como também a luminescência estimulada pela temperatura desses materiais na forma de pó e a eficiência radiante do protótipo de queimador de gás. Os resultados obtidos para o β-Y1,95Dy0,05Si2O7 comparados com a ítria (Y2O3) e concentrado de terras raras contento ítria (YTR) mostram-se promissores. Desenvolveu-se por processamento coloidal do β-Y1,95Dy0,05Si2O7 e utilizando-se o processo de conformação por réplica a partir da esponja vegetal Lufa Cylindrica, um protótipo de lâmpada de queimador de gás com boa resistência mecânica ao manejo, emissividade espectral no visível (λ=580nm) e eficiência radiante de 13%, com grande potencial para iluminação de ambientes internos de acordo com as recomendações da Comissão Internacional de Iluminação (CIE). / Yttrium disilicate (Y2Si2O7) shows luminescent proprieties and is a potential material to replace rare earth oxides in porous burner technology for lighting. In conformation process from suspensions the control of stability of particles in aqueous medium is an important step to produce ceramic components that show homogeneous microstructure and structural stability. This work presents studies about surface behavior, stability and rheological behavior of aqueous suspensions of Y2Si2O7 and β-Y1,95Dy0,05Si2O7 and aims to prepare suitable suspensions for replica method, and vegetable fibers were used as template to produce porous components for gas burners. In this study key parameters on stability and rheological behavior of suspensions were evaluated, as well as the stimulated luminescence of powders by increasing temperature and radiant efficiency of gas burner prototype. The results as compared with yttria and rare earth concentrate containing yttria are very promising. By colloidal processing of β-Y1,95Dy0,05Si2O7 and using replica method from Luffa Cylindrica vegetable sponge a prototype of gas burner lamp showing good handle strength, visible spectral emissivity (λ=580nm), radiant efficiency of 13%, and great potential to be used for lighting internal spaces according to the International Commission on Illumination (CIE).
474

Resposta humana à luz: alterações não visuais e o projeto luminotécnico residencial com LEDs / Dado não fornecido pelo autor.

Soares Filho, Ruy Barbosa 15 May 2018 (has links)
Esta pesquisa traz à tona, de forma interdisciplinar, estudos realizados e em andamento nas áreas de medicina, fisiologia, biologia, saúde pública, psicologia, engenharia e arquitetura, para investigar algumas alterações fisiológicas provocadas pela luz produzida pelos LEDs e, a partir da análise dos dados coletados, estabelecer em caráter preliminar novos parâmetros a serem considerados e aplicados ao projeto luminotécnico residencial que utiliza LEDs como fonte de luz. Desenvolvemos um protocolo para coletar os dados e comparar, para cada sujeito, o comportamento das variáveis entre dois períodos distintos, com a duração de 3 dias cada: um período em que, à noite, os sujeitos utilizaram óculos bloqueadores de luz azul (Período BB) e outro em que, também à noite, permaneceram expostos à iluminação artificial de LEDs em seus ambientes de maior permanência, previamente por eles definidos (Período LED). Verificamos a carga excretada de 6-sulfatoximelatonina na urina noturna de 12 horas (n=10), as variações de temperatura corporal (n=9) e as variáveis produzidas por meio da actimetria (n=10). Confrontamos estes dados com a literatura atual e com as características dos respectivos sistemas de iluminação. Do grupo de 10 sujeitos, 7 apresentaram redução da carga excretada de 6-sulfatoximelatonina do Período BB para o Período LED. A análise de temperatura corporal do grupo de 9 sujeitos, revelou que 7 deles apresentaram atraso de fase do respectivo ritmo do Período BB para o Período LED. A actimetria não revelou diferenças significativas entre os períodos. Porém, para o grupo que apresentou redução da carga excretada de 6-sulfatoximelatonina do Período BB para o Período LED, o L5 (período de 5 horas de menor atividade motora) apresentou um atraso de fase médio de 15 minutos. Os resultados desta pesquisa comprovam, pela primeira vez por meio de um estudo de campo, que os LEDs utilizados nos sistemas de iluminação artificial do ambiente residencial, possuem a capacidade de causar impactos deletérios na saúde dos usuários. / This research uses interdisciplinary ongoing studies in medicine, physiology, biology, public health, psychology, engineering and architecture, to investigate some physiological changes caused by the light emitted by LEDs and, based on the results, establish in a preliminary way, new parameters to be considered and applied to residential lighting projects using LEDs as a light source. We developed a protocol to collect some data and we compared, for each subject, the values between two distinct periods of 3 days each: the BB Period, where subjects wore blue-light blocking glasses at night, and the LED Period, where they were exposed to their room\'s LED lights at night. We verified the excreted load of 6-sulfatoxymelatonin in the 12-hour overnight urine (n=10), changes in pheripheral body temperature (n=9), and the variables of actimetry (n=10). We analyzed these data using information provided by the current literature and crossed these data with the characteristics of the lighting systems. Within the group of 10 subjects, 7 had a reduction in the excreted load of 6-sulfatoxymelatonin from the BB Period to the LED Period. The analysis of body temperature from the group of 9 subjects revealed that 7 of them showed acrophase phase delay from the BB Period to the LED Period. Actimetry did not reveal significant differences between these periods. However, for the group which showed a reduction in the excreted load of 6-sulfatoxymelatonin from the BB Period to the LED Period, the L5 (least active 5-hour period) presented, in average, a 15-minute phase delay. The results of this research prove, for the first time through a field study, that the LEDs used in residential lighting systems fave the capacity to cause deleterious impacts on users\' health.
475

A luz do dia no pensamento e prática projetual de arquitetos egressos da FAUUSP no periodo de 1985 a 2005 / Daylight in the thinking and design practice of architects who graduated at FAUSP between 1985 to 2005

Lacerda, Ana Cristina da Silva de 08 May 2012 (has links)
A luz é necessária para que a matéria se manifeste e se torne visível. A possibilidade da percepção do espaço e do vazio, da visualização de um componente, de um conjunto de formas ou do todo, onde a arquitetura se apresenta e se revela, dá-se em função da existência do fenômeno luz. A arquitetura dispõe elementos no espaço para captar, refletir, diluir e também emitir a luz. O uso da luz do dia como diretriz de projeto requer uma postura crítica que valorize igualmente uma relação íntima entre aspectos poéticos e aspectos técnicos; tendo como referência o contexto histórico-cultural e as condições ambientais do lugar, as necessidades programáticas, as técnicas construtivas disponíveis e, principalmente, os usuários. Pretende-se fazer uma reflexão sobre o processo de incorporação da luz do dia no processo criativo de arquitetos egressos da FAUUSP entre os anos de 1985 e 2005 que passaram a ocupar lugar de destaque no panorama da arquitetura contemporânea brasileira pelo fato do curso de graduação em Arquitetura e Urbanismo da FAUUSP ser reconhecido como referência na história do ensino e da pesquisa em arquitetura e urbanismo no Brasil e ter tradição no ensino da disciplina de Iluminação Natural. A matriz principal da arquitetura produzida pelos arquitetos, focos da pesquisa, é o Modernismo e o legado dos conteúdos acadêmicos. / Light is necessary for the substance to manifest itself and become visible. The possibility of space and emptiness perception, the ability to see a certain component, a set of forms or its combination, where architecture is presented and reveals itself, is due to the existence of the phenomenon known as light. Architecture has elements to capture, reflect, dilute and also emit light. The use of daylight as a guideline for project requires a critical posture that values an intimate relationship between poetic and technical aspects. Concerning also historical-cultural reference and the environmental conditions of the place, as well as programmatic requirements, construction techniques available and especially its users. It is intended to reflect on the process of incorporation of daylight in the creative process of architects who graduated from FAUUSP between the years of 1985 and 2005. That came to occupy a prominent place in the panorama of contemporary Brazilian architecture. Due to the fact that the graduation course in Architecture and Urbanism at FAU is recognized as a benchmark in the history of teaching and research in Architecture and Urbanism in Brazil. And have a tradition in the teaching of the discipline of Natural Lighting. The main style of the quoted architects is the legacy of Modernism and academic content
476

Interactive illumination and navigation control in an image-based environment.

January 1999 (has links)
Fu Chi-wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 141-149). / Abstract --- p.i / Acknowledgments --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction to Image-based Rendering --- p.1 / Chapter 1.2 --- Scene Complexity Independent Property --- p.2 / Chapter 1.3 --- Application of this Research Work --- p.3 / Chapter 1.4 --- Organization of this Thesis --- p.4 / Chapter 2 --- Illumination Control --- p.7 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Apparent BRDF of Pixel --- p.8 / Chapter 2.3 --- Sampling Illumination Information --- p.11 / Chapter 2.4 --- Re-rendering --- p.13 / Chapter 2.4.1 --- Light Direction --- p.15 / Chapter 2.4.2 --- Light Intensity --- p.15 / Chapter 2.4.3 --- Multiple Light Sources --- p.15 / Chapter 2.4.4 --- Type of Light Sources --- p.18 / Chapter 2.5 --- Data Compression --- p.22 / Chapter 2.5.1 --- Intra-pixel coherence --- p.22 / Chapter 2.5.2 --- Inter-pixel coherence --- p.22 / Chapter 2.6 --- Implementation and Result --- p.22 / Chapter 2.6.1 --- An Interactive Viewer --- p.22 / Chapter 2.6.2 --- Lazy Re-rendering --- p.24 / Chapter 2.7 --- Conclusion --- p.24 / Chapter 3 --- Navigation Control - Triangle-based Warping Rule --- p.29 / Chapter 3.1 --- Introduction to Navigation Control --- p.29 / Chapter 3.2 --- Related Works --- p.30 / Chapter 3.3 --- Epipolar Geometry (Perspective Projection Manifold) --- p.31 / Chapter 3.4 --- Drawing Order for Pixel-Sized Entities --- p.35 / Chapter 3.5 --- Triangle-based Image Warping --- p.36 / Chapter 3.5.1 --- Image-based Triangulation --- p.36 / Chapter 3.5.2 --- Image-based Visibility Sorting --- p.40 / Chapter 3.5.3 --- Topological Sorting --- p.44 / Chapter 3.6 --- Results --- p.46 / Chapter 3.7 --- Conclusion --- p.48 / Chapter 4 --- Panoramic Projection Manifold --- p.52 / Chapter 4.1 --- Epipolar Geometry (Spherical Projection Manifold) --- p.53 / Chapter 4.2 --- Image Triangulation --- p.56 / Chapter 4.2.1 --- Optical Flow --- p.56 / Chapter 4.2.2 --- Image Gradient and Potential Function --- p.57 / Chapter 4.2.3 --- Triangulation --- p.58 / Chapter 4.3 --- Image-based Visibility Sorting --- p.58 / Chapter 4.3.1 --- Mapping Criteria --- p.58 / Chapter 4.3.2 --- Ordering of Two Triangles --- p.59 / Chapter 4.3.3 --- Graph Construction and Topological Sort --- p.63 / Chapter 4.4 --- Results --- p.63 / Chapter 4.5 --- Conclusion --- p.65 / Chapter 5 --- Panoramic-based Navigation using Real Photos --- p.69 / Chapter 5.1 --- Introduction --- p.69 / Chapter 5.2 --- System Overview --- p.71 / Chapter 5.3 --- Correspondence Matching --- p.72 / Chapter 5.3.1 --- Basic Model of Epipolar Geometry --- p.72 / Chapter 5.3.2 --- Epipolar Geometry between two Neighbor Panoramic Nodes --- p.73 / Chapter 5.3.3 --- Line and Patch Correspondence Matching --- p.74 / Chapter 5.4 --- Triangle-based Warping --- p.75 / Chapter 5.4.1 --- Why Warp Triangle --- p.75 / Chapter 5.4.2 --- Patch and Layer Construction --- p.76 / Chapter 5.4.3 --- Triangulation and Mesh Subdivision --- p.76 / Chapter 5.4.4 --- Layered Triangle-based Warping --- p.77 / Chapter 5.5 --- Implementation --- p.78 / Chapter 5.5.1 --- Image Sampler and Panoramic Stitcher --- p.78 / Chapter 5.5.2 --- Interactive Correspondence Matcher and Triangulation --- p.79 / Chapter 5.5.3 --- Basic Panoramic Viewer --- p.79 / Chapter 5.5.4 --- Formulating Drag Vector and vn --- p.80 / Chapter 5.5.5 --- Controlling Walkthrough Parameter --- p.82 / Chapter 5.5.6 --- Interactive Web-based Panoramic Viewer --- p.83 / Chapter 5.6 --- Results --- p.84 / Chapter 5.7 --- Conclusion and Possible Enhancements --- p.84 / Chapter 6 --- Compositing Warped Images for Object-based Viewing --- p.89 / Chapter 6.1 --- Modeling Object-based Viewing --- p.89 / Chapter 6.2 --- Triangulation and Convex Hull Criteria --- p.92 / Chapter 6.3 --- Warping Multiple Views --- p.94 / Chapter 6.3.1 --- Method I --- p.95 / Chapter 6.3.2 --- Method II --- p.95 / Chapter 6.3.3 --- Method III --- p.95 / Chapter 6.4 --- Results --- p.97 / Chapter 6.5 --- Conclusion --- p.100 / Chapter 7 --- Complete Rendering Pipeline --- p.107 / Chapter 7.1 --- Reviews on Illumination and Navigation --- p.107 / Chapter 7.1.1 --- Illumination Rendering Pipeline --- p.107 / Chapter 7.1.2 --- Navigation Rendering Pipeline --- p.108 / Chapter 7.2 --- Analysis of the Two Rendering Pipelines --- p.109 / Chapter 7.2.1 --- Combination on the Architectural Level --- p.109 / Chapter 7.2.2 --- Ensuring Physical Correctness --- p.111 / Chapter 7.3 --- Generalizing Apparent BRDF --- p.112 / Chapter 7.3.1 --- Difficulties to Encode BRDF with Spherical Harmonics --- p.112 / Chapter 7.3.2 --- Generalize Apparent BRDF --- p.112 / Chapter 7.3.3 --- Related works for Encoding the generalized apparent BRDF --- p.113 / Chapter 7.4 --- Conclusion --- p.116 / Chapter 8 --- Conclusion --- p.117 / Chapter A --- Spherical Harmonics --- p.120 / Chapter B --- It is Rare for Cycles to Exist in the Drawing Order Graph --- p.123 / Chapter B.1 --- Theorem 3 --- p.123 / Chapter B.2 --- Inside and Outside-directed Triangles in a Triangular Cycle --- p.125 / Chapter B.2.1 --- Assumption --- p.126 / Chapter B.2.2 --- Inside-directed and Outside-directed triangles --- p.126 / Chapter B.3 --- Four Possible Cases to Form a Cycle --- p.127 / Chapter B.3.1 --- Case(l) Triangular Fan --- p.128 / Chapter B.3.2 --- Case(2) Two Outside-directed Triangles --- p.129 / Chapter B.3.3 --- Case(3) Three Outside-directed Triangles --- p.130 / Chapter B.3.4 --- Case(4) More than Three Outside-directed Triangles --- p.131 / Chapter B.4 --- Experiment --- p.132 / Chapter C --- Deriving the Epipolar Line Formula on Cylindrical Projection Manifold --- p.133 / Chapter C.1 --- Notations --- p.133 / Chapter C.2 --- General Formula --- p.134 / Chapter C.3 --- Simplify the General Formula to a Sine Curve --- p.137 / Chapter C.4 --- Show that the Epipolar Line is a Sine Curve Segment --- p.139 / Chapter D --- Publications Related to this Research Work --- p.141 / Bibliography --- p.143
477

Lighting effects on video display terminals

Atwood, Max J January 2010 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
478

O lighting design sob a perspectiva do design estratégico: construção de atmosferas para experiência

Luz, Natália Cardoso 31 August 2012 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-06-30T13:23:36Z No. of bitstreams: 1 NataliaC. Luz.pdf: 12307779 bytes, checksum: 53accbfb55fe02d87806bc07377efbf1 (MD5) / Made available in DSpace on 2015-06-30T13:23:36Z (GMT). No. of bitstreams: 1 NataliaC. Luz.pdf: 12307779 bytes, checksum: 53accbfb55fe02d87806bc07377efbf1 (MD5) Previous issue date: 2012 / Banco Santander / Banespa / A utilização de elementos e estímulos sensoriais no projeto de um ambiente proporciona a construção de atmosferas, que interferem diretamente na percepção que os usuários terão do ambiente. Esta pesquisa explora o lighting design como elemento chave na construção de uma atmosfera, associado à cor e dinâmicas de movimento da luz, buscando a construção de significados e a criação de vínculos entre usuário e ambiente. O trabalho foi desenvolvido a partir de pesquisa teórica, que buscou revisar conceitos como atmosfera e experiência a partir da lógica do design estratégico; e de um estudo experimental, que considerou a construção de duas atmosferas e buscou avaliar a percepção dos usuários. Resultados demonstraram que a criação estratégica de atmosferas permite potencializar a experiência do usuário no ambiente, a partir da percepção do usuário sobre a atmosfera proposta. / The use of elements and sensory stimuli in the design of an environment provides the construction of atmospheres, which directly interferes with the perception that users have of the environment. This research explores the lighting design as a key element in building an atmosphere associated with the color and dynamic movement of light, seeking the construction of meanings and the creation of links between user and environment. The work was developed from theoretical research, which sought to revise concepts like atmosphere and experience from the logic of strategic design, and an experimental study, which considered the construction of two atmospheres and sought to evaluate the perception of users. Results demonstrated that the strategic creation of atmospheres allows enhancing the user experience in the environment, from the user's perception about the atmosphere proposal.
479

Desenvolvimento de tubos solares aplicados em iluminação de interiores a partir de materiais poliméricos metalizados

Spacek, Anderson Diogo January 2017 (has links)
O presente trabalho teve como objetivo desenvolver sistemas tubulares de condução de luz natural propondo a substituição do alumínio revestido com prata (que é o sistema comercializado atualmente por diversas empresas internacionais), por polímero metalizado. Espera-se com isso diversificar os materiais empregados na fabricação destes dispositivos reduzindo significativamente o custo. Os sistemas tubulares de condução de luz natural permitem o aproveitamento da luz solar para iluminação de interiores, contribuindo para a redução do consumo de energia elétrica. No presente estudo foram avaliados como material estrutural os polímeros (PP, PS, PEAD, PEBD, ABS nas condições virgem e reciclada), revestidos com alumínio e cromo e submetidos à metalização por evaporação no vácuo (íon plating) ou por projeção catódica (sputtering). Os materiais poliméricos foram caracterizados quanto sua resistência mecânica através de ensaios de tração (norma ASTM D638). Os revestimentos de alumínio e cromo depositados nos materiais poliméricos, foram caracterizados quanto à adesão (norma ASTM D3359-09) e quanto à reflexividade (norma ASTM E903). Essas propriedades foram avaliadas comparativamente ao material empregado em um sistema tubular de condução de luz natural comercial (referencia). Os resultados obtidos dos ensaios realizados, demonstraram que os melhores sistemas obtidos foram o PP reciclado metalizado com alumínio pelo processo de projeção catódica, e também ABS e PS virgem metalizados com alumínio pelo processo de evaporação no vácuo. Para a validação em escala real, foram elaborados: um protótipo de PP reciclado metalizado com alumínio pelo processo de projeção catódica e um protótipo de ABS virgem metalizado com alumínio pelo processo de evaporação no vácuo. Enquanto, o tubo protótipo de ABS virgem metalizado com alumínio chegou em média diária a atingir 65% do rendimento comparado com o tubo referência, o PP reciclado metalizado com alumínio pelo processo de projeção catódica chegou apenas a 21%. Isso evidenciou a viabilidade técnica de construção de um tubo para condução da luz solar direta para iluminação utilizando ABS virgem metalizado com alumínio com rendimento de 65% do tubo de referência, o qual pode ser comercializado uma redução de custo estimado de 46,5% em relação a referência. / This paper aims to develop tubular daylight systems for transporting natural light by substituting silver coated aluminum (which is the system currently supplied by several international companies), for metalized polymer. This is expected to diversify the materials used in the manufacturing of those tubular devices, significantly reducing their cost. The tubular systems for conducting natural light enable to maximize the use of natural daylight for interior lighting, minimizing the consumption of electric energy. In this study some polymers (virgin and recycled PP, PS, HDPE, LDPE, and ABS) aluminum or chromium coated were evaluated as structural material. The coating were obtained metallization by vacuum evaporation (ion plating) or by cathodic projection (sputtering). The polymeric materials were evaluated for their mechanical resistance through tensile tests (American Society for Testing and Materials - ASTM D638 standard). The aluminum and chromium coatings deposited on polymeric materials were evaluated for their adhesion (ASTM D3359-09) and for their reflectivity (ASTM E903). These properties were measured comparatively to the material commonly used in a commercial tubular daylight conducting system (reference). The tests results showed that the best systems were the recycled PP metalized with aluminum by the cathodic projection process, and also virgin ABS and virgin PS metalized with aluminum by the vacuum evaporation process. For the real-scale validation, a prototype of recycled PP metalized with aluminum by the cathodic projection process and a prototype of virgin ABS metalized with aluminum by the vacuum evaporation process were made. While the prototype made with virgin ABS metalized with aluminum attained an average daily efficiency of 65% compared to the reference tube, the prototype made with recycled PP metalized with aluminum by the cathodic projection process attained only 21%. Thus, these results demonstrate the technical feasibility of producing a tubular direct daylight conducting system using virgin ABS metalized with aluminum with an efficiency of 65% of the reference tube at an estimated cost 46.5% lower than the reference tube.
480

A mathematical model for calculating transient heating or cooling loads from lighting

Green, Daniel Joseph January 2011 (has links)
Digitized by Kansas Correctional Industries

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