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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.
171

Desempenho térmico de cobertura verde utilizando a grama Brachiaria humidicola na cidade de São Carlos-SP

Andrade, Nixon César de 22 August 2007 (has links)
Made available in DSpace on 2016-06-02T20:09:08Z (GMT). No. of bitstreams: 1 1676.pdf: 2206138 bytes, checksum: c83c9d5aa6bb880c23dbdaa15df8077f (MD5) Previous issue date: 2007-08-22 / This work aims to analyze the thermal behavior of a green roof with the Braquiária grass (Brachiaria humidicola), that reaches 1m height, comparing it with a traditional roof (concrete slab on show). Considering temperature and relative humidity data obtained through field measurements in different months, the thermal performance of the green and traditional roofs was analyzed. The inside and outside temperatures, and inside superficial of two test-cells were analyzed. The outside superficial temperatures were estimated through computation program and the solar radiation data and wind speed, necessaries for the use of this program, were provided by the Water Resource and Applied Ecology Center (CRHEA,) and the Engineering School of São Carlos (EESC), both from the University of São Paulo (USP). The results indicate that, submitted to the local climate, the green roof presents optimum performance, particularly for decreasing the temperatures of external and internal roof surfaces. In the same test-cell it was recently realized a similar research, which used the Esmeralda grass (Zoysia japonica), a short vegetation. Comparing the measurement results for cold and hot periods, it was noticed differences between the thermal performance of the two grasses. / O objetivo deste trabalho é analisar o comportamento térmico de uma cobertura ajardinada com a grama Braquiária (Brachiaria humidicola), que atinge 1m de altura, comparando-a com a de uma cobertura tradicional (laje exposta). Considerando-se os dados obtidos por meio de monitoramentos com aparelhos registradores de temperaturas e umidades relativas, em diferentes épocas do ano, analisou-se o comportamento térmico das coberturas tradicional e verde. Foram medidas as temperaturas do ar no interior e no exterior das células-teste e as superficiais internas de ambas as células. As temperaturas superficiais externas foram estimadas por programa computacional e os dados de radiação solar e velocidade do vento, necessários para a utilização desse programa, foram fornecidos pelo Centro de Recursos Hídricos e Ecologia Aplicada (CRHEA) e pela Escola de Engenharia de São Carlos (EESC), ambos da Universidade de São Paulo (USP). Os resultados indicam que, submetida ao clima local, a cobertura ajardinada apresenta ótimo desempenho, particularmente por amortecer as temperaturas das superfícies externas e internas da cobertura. Nessa mesma célula-teste realizou-se recentemente uma pesquisa similar, mas que utilizou a grama Esmeralda (Zoysia japonica), uma vegetação rasteira. Comparando-se os resultados dos monitoramentos realizados, nos períodos de frio e calor, foram detectadas diferenças entre os comportamentos térmicos das duas gramas.
172

Desenvolvimento de metodologia para avaliação do potencial de utilização de sistemas de energia solar fotovoltaica em meios urbanos

Torres, Rafael Gerzson January 2015 (has links)
Este trabalho visa desenvolver uma metodologia, através de ferramentas computacionais de simulação, de avaliação de mapas solares para a análise de sombreamentos e da radiação solar incidente sobre as coberturas e telhados das edificações dentro do ambiente urbano e aplicá-la para a cidade de Porto Alegre. Desta forma é possível identificar os melhores espaços para alocar futuras instalações fotovoltaicas e evitar possíveis perdas por sombreamento ao longo do ano. Para tanto, foram selecionadas quatro regiões de estudo, cada uma representando uma tipologia de bairro e edificações. Os bairros Centro Histórico, São Geraldo, São Sebastião e Santana foram selecionados por representarem: edificações comerciais de escritórios, galpões comerciais (depósitos e oficinas), residencial de baixa altura e prédios residenciais, respectivamente. Após o desenvolvimento dos mapas solares, são realizadas estimativas para capacidade de instalação e produção de energia elétrica por sistemas fotovoltaicos em cada edificação. O software EnergyPlus produziu modelos termoenergéticos para quatro edificações típicas representando cada uma das regiões de estudo e, assim, proceder um balanço de energia em escala anual para o consumo energético e a produção de energia. Considerando as hipóteses de simulação e premissas de cálculo utilizadas, verifica-se que existe potencial para a geração distribuída de energia em escala urbana para as regiões de estudo. Um resultado significativo ocorreu para a região do bairro São Geraldo, onde as dez maiores áreas de telhado equivalem a 53% do potencial total de instalação fotovoltaica aplicada a edificações da região de estudo. Ainda, realizado o balanço de energia, foram analisados os cenários de investimento para cada tipologia de edificação típica, resultando em um retorno sobre o investimento entre 9 e 13 anos, dependendo do tipo de edificação. / This work aims to develop a methodology, through computer simulation tools, for evaluating solar maps for shading analysis and incident solar radiation on the building roofs within the urban environment. This methodology is applied in the city of Porto Alegre. Thus, it is possible to identify the best areas to allocate future photovoltaic systems and avoid possible shading losses throughout the year. Therefore were selected four study areas, each one representing one type of neighborhood and respective buildings. The neighborhoods Centro Histórico, São Geraldo, São Sebastião and Santana were selected because they represent: commercial/office buildings, warehouses/workshops, low-rise residential and residential buildings, respectively. After the development of solar maps, estimates were made for the capacity of installation and the electric energy produced by photovoltaic systems in each building roof. The EnergyPlus software produced an energy model for a typical building of each study area (neighborhood) and make an energy balance in annual scale for the energy consumption and energy production. Considering the simulation hypothesis and assumptions, it appears that there is potential for the distributed generation in urban scale for the four study areas. A significant result was found for the São Geraldo region, where only the top ten building roof areas equals to 53% of the total potential of building applied photovoltaic in the respective neighborhood region. Also, performing the energy balance, investment scenarios were analyzed for each typical building, resulting in a return on investment between 9 and 13 years, depending on the building type.
173

QUALIDADE E QUANTIDADE DE ÁGUAS PLUVIAIS ESCOADAS A PARTIR DE TELHADOS VERDES EXTENSIVOS EM SANTA MARIA-RS / STORMWATER QUALITY AND QUANTITY FROM EXTENSIVE GREEN ROOFS IN SANTA MARIA-RS

Pessoa, Jonas Onis 20 July 2016 (has links)
Fundação de Amparo à Pesquisa do Estado do Amazonas / Green roofs have increasingly become an integral part of urban environments, mainly due to their aesthetic benefits, thermal comfort and efficiency in controlling excess runoff. However, the effects of this emerging technology in the qualitative characteristics of rainwater is still poorly understood. In this study, we evaluated the quality of rain water runoff from two extensive green roofs and a roof built with corrugated fiber cement sheets (control roof) installed in Santa Maria - RS. In addition, we analyzed the performance of both types of roof for controlling storm water runoff. For qualitative analysis of water, were determined physical (turbidity, apparent color, true color, electrical conductivity, total solids, dissolved solids, suspended solids and temperature), chemical (pH, phosphate, total nitrogen, nitrate, nitrite, chloride, sulfates, BOD, and hardness), metal (copper, iron, zinc, lead and chromium) and microbiological parameters (total coliforms and E. coli). Differences in rain water quality obtained at collection points were assessed using parametric test (Test t) and non-parametric tests (Mann-Whitney and Kruskal-Wallis test) with a significance level of 5% probability. The control of storm water runoff was analyzed from the runoff coefficient (C) and the water portion stored in both types of coverage. The results showed that, in general, GRs have not improved water quality, as indicated by some authors. On both green roofs occurred an increase of chloride, electrical conductivity, color, BOD, hardness, total coliforms, E. coli, phosphate, sulfate and turbidity. However, it was observed that GRs are able to convert the slightly acidic rainfall into basic water, which confirms its potential to neutralize acid deposition. Except for a few parameters, the quality of the collected water from the control roof did not differ significantly compared to GRs water. By comparing the results with the Brazilian environmental legislation, we noted that the runoff from all three roofs have potential for non-potable uses, such as floor and sidewalks washing, garden irrigation, toilet flushing, among others. About the performance of roofs in controlling storm water runoff, there was a significant efficiency of green roofs compared to the roof built with corrugated fiber cement sheets. This result was typified by the average values of flow coefficient, about 0.43 for GRs and 0.83 for control roof. However, the efficiency of green roofs controlling runoff proved to be very sensitive to weather conditions and antecedent soil moisture. To a future study about performance and interaction of various factors that could influence green roofs water quality and in its efficiency and controlling storm water runoff, we suggest long-term studies with different types of substrates, plant species and installation of the structures in locations with other types of occupation and environmental conditions, different from those verified in this work. / Os telhados verdes (TVs) têm cada vez mais se tornado parte integrante dos ambientes urbanos devido, principalmente, aos seus benefícios estéticos, conforto térmico e diminuição do escoamento superficial de águas pluviais. Contudo, os efeitos dessa emergente tecnologia nas características qualitativas de águas de chuva ainda é pouco compreendido. Neste trabalho foi avaliada a qualidade de águas de pluviais escoadas a partir de dois telhados verdes extensivos e de um telhado de fibrocimento (telhado controle) instalados em Santa Maria-RS. Complementarmente, analisou-se o desempenho de ambos os tipos de coberturas no controle quantitativo do escoamento pluvial. Para a caracterização qualitativa da água, foram determinados os parâmetros físicos (turbidez, cor aparente, cor verdadeira, condutividade elétrica, sólidos totais, sólidos dissolvidos, sólidos suspensos e temperatura), químicos (pH, fosfato, nitrogênio total, nitrato, nitrito, cloretos, sulfatos, DBO, e dureza), metais (cobre, ferro, zinco, chumbo e cromo) e microbiológicos (coliformes totais e E. coli). As diferenças na qualidade da água de chuva obtidas nos diferentes pontos de coleta foram avaliadas utilizando teste paramétrico (Test t) e testes não paramétricos (Mann-Whitney e Kruskal-Wallis), com um nível de significância de 5% de probabilidade. O controle do escoamento pluvial foi analisado a partir do coeficiente de escoamento (C) e da parcela de água armazenada nos dois tipos de coberturas. Os resultados apontaram que, em geral, os TVs não melhoraram a qualidade da água, como indicado por alguns autores. Ambos telhados verdes atuaram como fonte de cloretos, condutividade elétrica, cor, DBO, dureza total, coliformes totais, E. coli, fosfato, sulfato e turbidez. Contudo, observou- que os TVs foram capazes de converter o caráter ligeiramente ácido da água pluvial para básico, confirmando o seu potencial na neutralização de deposições ácidas. Com exceção de alguns parâmetros, a qualidade da água coletada do telhado controle não se diferiu significativamente em comparação às dos TVs. A partir da comparação dos resultados com as legislações ambientais consultadas, observou-se que as águas escoadas dos dois tipos de telhados apresentam características com potencial para usos não potáveis, tais como lavagem de pisos, calçadas, irrigação de jardins, descargas de bacias sanitárias, dentre outros. Com relação ao desempenho dos telhados no controle do escoamento pluvial, constatou-se uma significativa eficiência das coberturas verdes comparativamente ao telhado de fibrocimento. Esse resultado ficou tipificado pelos valores médios do coeficiente de escoamento, cerca de 0,43 para os TVs e de aproximadamente 0,83 para o telhado controle. Para melhor investigar a atuação e interação dos diversos fatores que podem influenciar na qualidade da água dos telhados verdes e também na sua eficiência quanto ao controle do escoamento pluvial, sugere-se estudos de longo prazo e com diferentes tipos de substratos, espécies vegetais e a instalação dessas estruturas em locais com diferentes tipos de ocupações e outras condicionantes ambientais distintas das verificadas neste trabalho.
174

Respuesta térmica de edificaciones con envolventes vegetales: cubiertas verdes y fachadas verdes / Thermal response in buildings with green covers: green roofs and green facades

Nuria Pérez Gallardo 16 March 2017 (has links)
El presente proyecto propuso un método experimental de medición de temperaturas internas con el fin de estudiar, comparar y entender la respuesta térmica frente al frío y al calor de cuatro células de ensayo denominadas Control (Sin vegetación) y tres células de ensayo con diferentes combinaciones de vegetación (cubiertas y fachadas) instaladas en una región de clima tropical. En ellas fueron medidas las temperaturas superficiales internas (TSI) y temperaturas del Bulbo Seco (TBS) mediante equipos específicos, un data logger, conectado a dos multiplicadores. Los datos fueron recogidos por un año y dentro de ese periodo fueron seleccionados los días críticos a estudiar. Varios datos climatológicos fueron considerados para abordar la influencia de las oscilaciones del tiempo meteorológico (episodios climáticos) en el ambiente interno construido, para lo cual fueron aplicados fundamentos de la Climatología Dinámica frente al comportamiento térmico de las células de ensayo. Los datos de las principales variables climáticas (radiación solar, humedad relativa y precipitación) fueron registradas en la Estación Meteorológica del CRHEA. Los resultados revelan que la célula de ensayo con vegetación en cubierta y fachadas, presenta más resistencia a las variaciones de temperaturas diarias, es decir, mejor comportamiento térmico, ya que muestra las menores amplitudes térmicas, los mayores retrasos térmicos, las menores temperaturas en días de calor extremo y las mayores en días de frío. Durante el día crítico de calor, las mayores diferencias entre las temperaturas máximas internas del aire, se presentan entre la célula construida con materiales convenciones y la célula que posee fachadas verdes y cubierta vegetal, de 2ºC y en torno a 3ºC en el caso de las temperaturas superficiales. Para el día crítico de frío, la diferencia entre ellas es de 1ºC para los valores de temperatura del aire, y de 2.2ºC para valores de temperaturas superficiales. Así, uso de vegetación en los edificios puede ser considerado una técnica capaz de mantener las condiciones internas más placenteras no solo en épocas calurosas, reduciendo la incidencia de la radiación solar directa, sino también en invierno, debido a su propiedad de aislante térmico que impide las rápidas pérdidas de calor, como ocurre en la célula sin vegetación. Los resultados obtenidos ponen de manifiesto que las hipótesis planteadas fueron alcanzadas, comprobando así, que el uso de vegetación combinado en fachadas y cubiertas contribuye a la mejora del comportamiento térmico, favoreciendo las condiciones térmicas internas en periodos de mayor o menor temperatura externa. / The present research proposed an experimental method for measuring internal temperatures of buildings, in order to study, compare, and understand the thermal response of four test cells against cold and heat, determined: control (without vegetation) and three test cells with different combinations of vegetation (on roofs and/or facades); installed in a tropical climate region. Internal surface temperatures (IST) and dry bulb temperatures (DBT) were measured using appropriate equipment, consisting of a data logger connected to two multipliers. Data were collected for one year and, during that period, the critical days that would be assessed were selected. Climatic data were considered in order to evaluate the influence of weather oscillations (climatic events) on the internal built environment, for which the principles of Dynamic Climatology were applied to understand the thermal behaviour of the test cells. The data obtained from the primary climatic variables (solar radiation, relative humidity, and precipitation) were recorded at the CRHEA. The results showed that the test cell with a green roof and green facades displayed higher resistance to changes in daily temperature, i.e., better thermal behavior, since it faced lower temperature intervals, higher thermal delays, lower temperatures on days of extreme heat, and higher temperatures on cold days. With respect to the critical heat day, the main differences between maximum internal air temperatures occurred between the cell constructed with conventional material and the cell that was built with green facades and a green roof, of 2°C in relation to the internal air temperature, and approximately 3°C with respect to surface temperatures. Regarding the critical cold day, the difference between test cells was of 1°C for air temperature values, and 2.2°C for surface temperature values. Therefore, the use of vegetation in construction can be considered a technique capable of maintaining the most pleasant indoor conditions, not only in hot climates, reducing the incidence of direct solar radiation, but also in the winter, due to thermal insulation properties that prevent the rapid loss of heat, which occurs in cells lacking vegetation. The obtained results show that the initial hypotheses were proven, thus confirming that the application of vegetation on facades and roofs contributes to the improvement of thermal performance, favoring internal thermal conditions during periods of higher or lower external temperatures.
175

Exploring the Residents' Attitude towards Greening Buildings and their Willingness to take action: An Empirical Survey Study in Deutz, Cologne

Burggraf, Tamina January 2020 (has links)
In times that reveal the consequences of climate change, cities are using urban greening as a potential measure in their climate change adaptation and mitigation strategies. Greenery in the city regulates the climate and balances temperature extremes through evapotranspiration and air humidification, spending shade and increased air circulation. Many cities in Germany, such as the City of Cologne, have established funding programmes for private stakeholders to support the greening of buildings. Greened buildings contribute to a reduction of the urban heat island effect by decreasing temperatures through increased evapotranspiration, increased air circulation and air humidification and a higher reflective power (albedo). The greening of buildings also cools down the building itself forming a natural insulation layer, shading and the reflection of sun energy. However, in most cities the potential for houses that could be greened is barely utilized. This study explores variables that influence the residents’ attitudinal and behavioural acceptance towards greening their building in Cologne Deutz. Survey research was conducted based on a theoretical framework that explains how external variables form beliefs that lead to attitudinal acceptance (positive attitude) and eventually behavioural acceptance (actual behaviour). The survey was designed to examine attitudinal acceptance and behavioural intention to act, as behavioural acceptance is difficult to measure. The main variables found to influence the residents’ attitudinal acceptance and behavioural intention towards the greening of buildings were ecological aspects, such as an increase of nature in the urban environment, an improvement of the urban climate, air quality and street cooling, and climate change. Visual-aesthetic aspects also played a major role, while finances and funding possibilities had a special influence on the perceived ease of use of greening one’s building. Amongst the sample of this study attitudinal acceptance and behavioural intention were categorized as high. Reasons that could explain the low amount of greening measure implementation were a possible lack of knowledge (of funding possibilities), a low number of private property owners, and an imbalance in the distribution of tangible advantages and disadvantages amongst tenants and landlords.
176

Avhjälpande åtgärder vid snölaster på låglutande industritak med långa spännvidder / Remedies for snow loads on low-sloping industrial roofs with long spans

Bengtsson, Marcus, Reinholdsson, Sofie January 2021 (has links)
Purpose: When introducing new construction standards arises some uncertainties due to overlapping with the old construction standards. Because of these uncertainties’ roofs have collapsed due to excessive snow loads. To ensure a safe workplace for companies responsible for snow removal, accepted means in connection with snow removal and the work environment will be studied. The final goal is to find and study new methods to make the work safer and more efficient. Method: The work contains both qualitative and quantitative data. The method is a case study with the data collection techniques measurement, observation, personal communication and document and literature study. All of these are necessary to be able to answer the questions and achieve the goal. Findings: The techniques used today regarding snow removal give a good result, but the majority are very time-consuming and risky for the employers who perform the work on the roofs. Several new techniques and means have been described that would be able to perform the same work in a more efficient and sustainable way seen from a work environment point of view. Implications: To limit the time spent on the roof would contribute to a safer workplace. Today there are several means and techniques that after being installed, can operate, and remove snow on its own. This would be safe and efficient. The only danger for the staff is when installing and maintenance. Limitations: The report is limited by the fact that not all types of roofs have been examined. The study focuses on roofs that are within a snow zone of 2.5 kN/m2 or lower. Keywords: Snow removal, working environment, low-sloping roofs, handle snow loads. / Syfte: Överlappningar när nya konstruktionsregler tagits fram har skapat osäkerhet kring dimensioneringar och tyvärr lett till att takras uppstår på grund av allt för stora snölaster. För att skapa en tryggare arbetsplats för företag som ansvarar för snöröjning kommer vedertagna hjälpmedel och tekniker i samband med snöröjning och hur arbetsmiljön ser ut vid pågående arbete studeras. Slutligen är målet att studera nya metoder som bidrar till ett effektivare och säkrare arbete. Metod: Arbetet består av både kvalitativa och kvantitativa data. Metoden som användas är fallstudie med datainsamlingsteknikerna mätning, observation, personlig kommunikation och litteraturstudie. Alla datainsamlingsteknikerna är nödvändiga för att kunna besvara frågeställningarna och uppnå målet. Resultat: Teknikerna som är vedertagna idag gällande snöröjning ger ett bra resultat men majoriteten är mycket tidskrävande och riskfyllda för personer som utför arbetet. Främst när det gäller arbetsmomenten som utförs uppe på tak. Flera nya tekniker och hjälpmedel har redovisats som skulle bidra till att företag kan utföra samma arbete på ett sätt som anses betydligt effektivare och mer hållbart ur arbetsmiljösynpunkt. Konsekvenser: Ett minskat arbete på tak skulle bidra till en säkrare arbetsplats. Det finns flertalet tekniker och hjälpmedel ute på marknaden som efter viss installation skulle kunna utföra snöröjningen på egen hand, vilket innebär en effektivisering. Detta innebär också att den enda risken som finns för personal är vid installation och underhåll och därmed är arbetsmiljön så säker som är möjligt. Begränsningar: Rapporten begränsas av att inte alla typer av tak undersökts. Studien fokuserar på tak som finns inom snözon 2,5 kN/m2 eller lägre. Nyckelord: Snöröjning, arbetsmiljö, låglutande tak, hantering snölaster.
177

Městský dům - architektura kombinace funkcí / City House – Mixet Use Architecture

Mertlíková, Klára January 2013 (has links)
The subject of the thesis is an architectural project of urban structure - a town house in Brno - Zábrdovice. The design uses the principle of multiplicity, which is characterized by multiplying of the site, using of roof planes and highlighting the object above the ground. The material of object is formed by the gradual reduction of the structure consisting of four blocks arranged around a central atrium. The building respects the height of the surrounding buildings, on the west side it has 5 floors, towards the river Svitava the height of the building gradually decreases. A significant feature is the use of greenery on roofs. Ventilated facade of the building will consist of perforated steel sheets Cor-ten and facade panels Cembrit.
178

Bytový dům / Apartment Building

Novotná, Petra January 2013 (has links)
This diploma thesis solver the newly apartment building in Kuřim. It is a building with tree floors and basemet. The claccing of Porotherm 300mm and is insulated by contact insulation. The roofs are flat. The windows are plastic. In the basement asre garages, cellars, technical room and bicycle room. The other floors are flats.
179

Víceúčelová sportovní hala / Multifunctional sports hall

Habarta, Michal January 2015 (has links)
Multifunctional sports hall designed as the local city sporting center. It’s including sport hall, pool hall,squash hall, and the parts including changing rooms, showers, toilets and technical equipment. The roofs are flat, the object has no cellar.
180

Reducing CO2 emissions of conventional fuel cars by vehicle photovoltaic roofs

Lodi, Chiara, Seitsonen, Antti, Paffumi, Elena, De Gennaro, Michele, Huld, Thomas, Malfettani, Stefano 21 December 2020 (has links)
The European Union has adopted a range of policies aiming at reducing greenhouse gas emissions from road transport, including setting binding targets for tailpipe CO2 emissions for new light-duty fleets. The legislative framework for implementing such targets allows taking into account the CO2 savings from innovative technologies that cannot be adequately quantified by the standard test cycle CO2 measurement. This paper presents a methodology to define the average productivity of vehicle-mounted photovoltaic roofs and to quantify the resulting CO2 benefits for conventional combustion engine-powered passenger cars in the European Union. The method relies on the analysis of a large dataset of vehicles activity data, i.e. urban driving patterns acquired with GPS systems, combined with an assessment of the shading effect from physical obstacles and indoor parking. The results show that on average the vehicle photovoltaic roof receives 58% of the available solar radiation in real-world conditions, making it possible to reduce CO2 emissions from passenger cars in a range from 1% to 3%, assuming a storage capacity of 20% of the 12 V battery dedicated to solar energy. This methodology can be applied to other vehicles types, such as light and heavy-duty, as well as to different powertrain configurations, such as hybrid and full electric.

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