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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.
651

Contribuições ao uso de diodos emissores de luz em iluminação pública

Rodrigues, Cláudio Roberto Barbosa Simões 17 December 2012 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-06-03T12:39:45Z No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 5762936 bytes, checksum: 8a7ae73391a9d56af3c18605a924763d (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-02T13:21:41Z (GMT) No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 5762936 bytes, checksum: 8a7ae73391a9d56af3c18605a924763d (MD5) / Made available in DSpace on 2016-07-02T13:21:41Z (GMT). No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 5762936 bytes, checksum: 8a7ae73391a9d56af3c18605a924763d (MD5) Previous issue date: 2012-12-17 / No intuito de aportar contribuições ao uso de diodos emissores de luz (ou LEDs, do inglês Light Emmiting Diodes) em sistemas de iluminação pública, cobrindo lacunas existentes no cenário nacional, este trabalho traz uma ampla análise sobre este tema. São apresentados conceitos básicos da fotometria clássica e um estudo sobre adaptações da fotometria para baixos níveis de luminância, que é a condição observada nas vias públicas durante o período noturno. Propõe-se a utilização de métricas escotópicas em sistemas de iluminação pública, uma vez que estas melhor representam a real sensação visual (se comparadas às métricas clássicas – fotópicas) nas condições de iluminamento típicas observadas nestes sistemas. Aspectos gerais da iluminação pública e um histórico da evolução do sistema nacional são brevemente apresentados bem como uma discussão sobre a situação atual deste sistema e das tecnologias utilizadas. O trabalho traz também um estudo sobre características ópticas, elétricas e mecânicas dos LEDs e uma análise dos diferentes tipos de LEDs brancos mais utilizados (HB – High Brightness – e HP – High Power – LEDs). Algumas normas e recomendações aplicáveis à utilização de LEDs em iluminação pública são analisadas e discutidas, com o intuito de se investigar lacunas ainda não cobertas pela normatização existente. Análises de resultados de ensaios de laboratório e de campo, inéditos no país, realizados com alguns modelos de luminárias LED para iluminação pública disponíveis no mercado, são também apresentadas. Um estudo sobre acionamento de LEDs é realizado, abordando técnicas de equalização de corrente entre arranjos série de LEDs associados em paralelo e diferentes tipos de circuitos de acionamento para LEDs. São propostas, analisadas e implementadas uma estrutura inédita de baixo custo para a equalização de corrente e um circuito para o acionamento de LEDs baseado na integração de dois conversores cc cc não isolados. A topologia de dois estágios proposta é composta por um conversor boost no primeiro estágio, utilizado para a correção do fator de potência e por um conversor buck no segundo estágio, utilizado para o controle da corrente nos LEDs. Por fim, o acompanhamento da implantação e do desempenho, ao longo de dez meses, do projeto piloto de iluminação pública empregando LEDs instalado no anel viário da Faculdade de Engenharia da UFJF é apresentado. / In order to present contributions to the use of light emitting diodes (LEDs) in public lighting systems, covering gaps on the national scenario, this work encompasses abroad analysis related to this issue. Basic concepts of classical photometry are presented and so a study of photometry’s adaptations for low luminance levels. It is proposed the use of scotopic metrics for street lighting systems, since they can better represent the actual visual sensation (when compared to the classical one – photopic metrics) on its typical nighty conditions. General aspects of street lighting and the history of the national’s public lighting system are briefly presented as well as a discussion about the current situation of the Brazilian system and technologies adopted. The work also brings a study of mechanical, electrical and optical characteristics of LEDs and an analysis of the two different types of commonly used white LEDs (HB – High Brightness – and HP – High Power - LEDs). Some standards and recommendations related to the use of LEDs in street lighting are analyzed and criticized, with the aim of show some gaps not yet covered by the existent standards. An unprecedented analysis regarding laboratory and field test benchmarking, taken for some luminaires available in commerce, is also presented. A study of LED driving is presented, covering equalization techniques for parallel LEDs strings and different types of LED driving circuits. It was proposed, analyzed and implemented a novel and low cost structure for current equalization and an LED driver, based on the integration of two non-isolated dc dc converters. This proposed two stages topology is composed by a boost converter, on the first stage, employed to the power factor correction and a buck converter, on the second stage, to control the LED’s current. Finally, the process of monitoring the installation and the performance, during ten months, of the LEDs public lighting pilot project, on the roadway belt of Engineering Faculty of UFJF is presented.
652

Illuminating a Tragic Miasma in Shepard’s A Particle of Dread

Thomas, Benjamin 07 January 2021 (has links)
Sam Shepard was a playwright who used a variety of stories and styles to explore and understand the country he called home, The United States of America. This thesis launches the process of understanding how Greek tragedy had influenced the work of Shepard in his explorations by looking at Shepard’s final play before his passing, A Particle of Dread (Oedipus Variations). Using the concept of miasma that has been established as important to Greek tragedy to analyze A Particle of Dread and its primary source work, Oedipus Rex, this thesis reveals the extent of the ancient tragic form’s presence in Shepard’s last play. To do so, I approach the work in a combination of theory and practice. I first use dramaturgical analysis of Oedipus Rex, to explain what tragic role miasma has in Sophocles’ play. This is followed by a mirrored dramaturgical analysis of A Particle of Dread to uncover and compare what place miasma (and therefore tragedy) has in Shepard’s play. Following this is the review and analysis of five performance workshops exploring scenes of Shepard’s play which used a combination of performance and lighting to physicalize that dramaturgical work so as to further it and hopefully reveal new aspects through their embodiment. This dramaturgical and practical work results in the discovery of how and to what end Shepard has chosen to use the Grecian content style to analyze and commentate on Western society. The work also offers the chance to compare how the engagement with pollution has changed from the characters of 5th Century BCE Greece to 2014 America, and what that might mean for 2020 onwards.
653

Energetick a provozn­ optimalizace syst©mu veejn©ho osvÄtlen­ / Energy Optimization and Operation of Public Lighting

Houdek, Michal January 2010 (has links)
An objektive of this university graduation work is an essay about any possibilities for energy savings with operation optimalization of public lightings. Understandings and introduction operation problems of public lighting is devote in first part of this work. Here we can chapters as Importance of public lightings or Gulations and norms in ralation to public lightings. The bigist and special attention is concentrated to description to public lightings systems and it is basic components. Another main part of this work is demonstration of used systems that are leading to energy savings for public lightings. These problems are detailed and explained in chapter Regulation of public lighting systems. This graduation work is describing individual types of regulation with the systems that are used with these regulatios in systems of public lightings. The assignment of last part of graduation work was to make sample calculation of energy demand and calculatin of yearly consumption on exemplary temporary system of public lightings. For this occasion was extra special auxiliary application sytem set up inside the Microsoft Excel program where all individual calculations were done.
654

Ekonomická efektivnost a finanční proveditelnost projektu realizovaného obcí / Economic Efficiency and Financial Feasibility of Project Realized by Municipality

Vik, Vladimir January 2014 (has links)
This diploma thesis deals with a public lighting and its direct impact on the financial management of the municipality. Within this analysis the basic methods and ways, which the municipality use in the field of a management and a maintenance of the public lighting system, were described. The eventual form of the reconstruction of the public lighting in the Černožice village was also proposed. In a response to this proposal possible ways of financing this investment project were subsequently outlined. The secondary aim of this thesis was to create a concise database of implemented projects of the reconstruction in other municipalities and comparison of these results.
655

Návrh veřejného osvětlení obce / Proposal of the village public lighting

Schittenhelm, Dominik January 2016 (has links)
The thesis is divided into several parts. The first part is theoretical and its main focus is the description of public lighting and the theory regarding lighting technology. The second part continues with the research of the current state in Bezděkov village. The thesis further describes the proposal for the village public lighting with the use of HPS and LED technology, where village models are made for both options to show the requested result. The last part of the work deals with cables dimensioning, the selection of the most effective regulations for lighting, and finally the economic assessment of both projects, while both the investment expenses and the public lighting service fees for the next 20 years are included.
656

Měření kvality osvětlení na operačních sálech / Measurement of operating room lights quality

Rovná, Tereza January 2016 (has links)
This thesis is focused on measuring the quality of lighting in operating rooms. Operating lights are very demanding in terms of quality requirements for each parameter, so it is important to specify exactly these parameters and check them regurarly. To measure the quality of the light source, was used a special kit from Maquet. Measurement procedure was not as accurate as it was for operating lighting need, therefore, this work includes a proposal to improve the measurement of quality lighting in operating theaters. In cooperation with University Hospital Brno Bohunice University Hospital Motol and the company Maquet measured nine operating lights, each light were compared in terms of parameters such as maximum light intensity, light distribution in the surgical field. In each category were selected several lighting, which reached the best results. The various parameters were compared with values declared by the manufacturer.
657

Bezdrátový systém pro vyhodnocení řízení osvětlení v budovách s cílem získat informace vedoucí k úsporám / Wireless System for Evaluation of Lighting Control in Buildings for Obtaining Information Leading to Savings

Malinowski, Radim January 2015 (has links)
The aim of the thesis is to design a system based on wirelessly comunicating devices that will be able to record an information about persons presesce in certain area. Aquired data will served for evaluation of the area lighting system efficiency. Partial goals related to this work are: to analyze electricity consumption mesaurement methods, to analyze presence and movement detection methods, to analzye wireless communication methods, to desin system's HW and SW including realization, to put system into a real operation and finally, to evaluate measured data.
658

Upplevelse av ljusrummet mellan fasadbelysning på historiska byggnader och stadsrummet / The experience of the light zone between facade lighting on historic buildings and the cityscape

Nylander, Erik, Söderberg, Johan January 2020 (has links)
This study was conduct as a candidate thesis at Jönköping’s School of Engineering. The purpose of the study was to examine how the light zone of façade lighting on a historical building is perceived in correlation to the cityscape. Historical buildings are an important part of the cityscape and connect the identity of the city, the cultural heritage, and the history of the building to the inhabitants. However, currently there is little published research within the area perception of façade lighting. The study is conducted as three case studies on the buildings: Rådhuset (the townhall) in Jönköping, Grand Hotel in Stockholm, and the Stadshuset (City hall) in Gothenburg.  The case studies used qualitative observational methods (Lynch /Branzell, PERCIFAL & FOG). To be able to compare the different objects a new method was developed by the authors, named “FOG”. FOG stands for the English word fog.  The new method is based on methods established by Lynch, Branzell, Cullen, and the optical scale. Our results indicate that the new method FOG is suitable to use when planning for façade lighting on existing facades, historical or not. FOG also have the potential to be used on other objects than facades when evaluating or working with the cityscape. Historical buildings façade suitability for façade lighting is based on its ornamentation and correlation with the urban space. Lighting on historical building façades increases the accessibility of the area and the perception of exclusiveness of the area. / Studien genomfördes som ett examensarbete vid Jönköpings Tekniska högskola. Syftet med studien är att undersöka hur ljusrum upplevs i samband med historiska fasader och stadsrummet.  Historiska byggnader är en viktig del av stadsrummet samt stadens identitet, kulturarv och historia. I dagsläget finns nästintill ingen tidigare forskning publicerad på upplevelsen av fasadbelysning. Studien genomfördes som tre fallstudier på platserna: rådhuset i Jönköping, Grand hotell i Stockholm och stadshuset i Göteborg med kvalitativa observationsmodeller (Lynch / Branzell, PERCIFAL & FOG). För att kunna jämföra de olika objekten har författarna tagit fram en egen metod kallad ”FOG”. FOG kommer från det engelska ordet dimma. FOG grundar sig i metoderna Lynch, Branzell, Cullen och optisk skala. Studien visar att FOG kan användas vid planering och som observations metod av fasadbelysning av en befintlig byggnad. FOG har även potential att kunna användas på andra objekt och för att stödja arbete med stadsgestaltning. En historisk fasads lämplighet för belysning påverkas av fasadens ornamentering och relation till stadsrummet. Resultaten från studien visar att belysning på historiska fasader ökar tillgängligheten av platsen, samt ökar upplevelsen av exklusivitet.
659

Analyzing Campus Safety: A Survey of Perceived Risk, Crime and Outdoor Lighting Levels

Marcheskie, Justin S. 11 June 2019 (has links)
No description available.
660

Goniochromatic Gradients : Dichroic Color, Thin-Film Optics and Artificial Light

Eggeling, Erik Axel January 2018 (has links)
This thesis is about the multicolored gradients seen when using certain dichroic color lters with artificial light. As of now, this phenomenon lacks a unambiguous descriptor, and “Goniochromatic Gradient” is proposed. With help of optical physics, the science of color vision and information about dichroic products, principles for the relationship between goniochromatic gradients and dichroic filters are formulated for anyone interested in exploring this visual phenomenon.

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