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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.
81

SIMULERING AV SPECIFIK ENERGIANVÄNDNING FÖR ETT FIKTIVT ATTEFALLSHUS : En undersökning om ett generellt Attefallshus kan klara det nu gällande BBR-kravet för småhus

Netzell, Pontus January 2016 (has links)
Energy efficiency in the building sector is crucial for many countries in succeeding with the completion of goals regarding energy efficiency. This study has investigated if there are any possible and reasonable solutions for Attefallshus in Sweden to meet the demands of the National Board of Housing regarding energy performance in houses. By building a model and calculating the annual energy usage for a specific Attefallshus, through simulations with the software IDA ICE and general input, an energy audit has been obtained. By comparing the specific energy usage for the studied case with the requirement the conclusion that it is possible for this small building to achieve a low enough energy usage to meet the demand. Solar cells are the key to accomplish the target of a low specific energy usage and by combining this with an effective system for heating it possible to get under the limit. The usage of domestic hot water is a very large part of the building specific energy usage and alone almost reaches the set bounds which is why it is of great importance to carefully design systems and to regain heat with effective ventilation. A large part of the energy usage in Attefallshus is related to the user why awareness and careful usage of energy is a significant factor in reaching a low specific energy usage.
82

Sistemas prediais de aquecimento de água a gás: Parâmetros de dimensionamento e gerenciamento / Building systems of gas water heating: parameters of design and management

Chaguri Junior, Jose Jorge 30 March 2009 (has links)
Os sistemas prediais de aquecimento de água são responsáveis por uma parcela significativa no consumo de energia do país, sendo que a eficiência do uso desta energia está relacionada com a qualidade dos projetos e de alternativas construtivas que possibilitam racionalizar o uso dos recursos naturais. Com a tendência de incorporação da medição individualizada de água e do aquecimento solar, algumas concepções de projetos hidráulicos foram alteradas, entre elas, a introdução de sistemas centrais coletivos de aquecimento de água no setor residencial. Porém, os métodos de dimensionamento destes sistemas são restritos à determinação do estado estático da infraestrutura e dos equipamentos envolvidos. Conhecendo as características de uso da população é possível introduzir sistemas de monitoração e gestão que alterem o dimensionamento das centrais de aquecimento, conforme a demanda instantânea, gerando reduções de perdas térmicas. Este trabalho consiste em analisar as variáveis de um sistema predial de aquecimento central a gás e o impacto na implantação de sistemas de monitoração e gestão. / The building systems of water heating are responsible for a significant parcel of energy consumption in country, and the efficiency of use of this energy is related to the quality of projects and constructive alternatives that allow rationalizing the use of natural resources. With the trend of incorporating the measurement of individual water and solar heating, some conceptions of hydraulic projects were changed including the introduction of collective central heating water in the residential sector. However, the methods of these systems are restricted to the determination of the static state of infrastructure and equipment involved. Knowing the characteristics of populations use is possible to introduce systems of monitoring and management to change the design of central heating as the instant demand, causing reductions in thermal losses.
83

Avaliação de coliformes totais residuais em creches de suínos após lavagem, desinfecção e vazio sanitário / Evaluation of total coliforms contamination in nursery pigs facilities after washing, disinfection and downtime

Mion, Ligiani January 2017 (has links)
A colonização por micro-organismos patogênicos em creches de suínos é um fator importante na disseminação de doenças e surtos no rebanho. O controle desses patógenos se dá principalmente por medidas de biosseguridade, como a prática da limpeza, desinfecção e vazio sanitário das instalações. O presente estudo avaliou a carga bacteriana após o processo de limpeza e desinfecção, durante o período de 3 dias de vazio sanitário, em duas creches de suínos, pelo uso de placas de contato com meio seletivo para coliformes totais. As contagens bacterianas foram analisadas considerando três fatores (água, detergente e desinfetante) em dois níveis para cada (água: fria/quente, detergente e desinfetante: presença/ausência). Foram usadas 4 baias em cada tratamento, 4 pontos de cada baia e cada ponto foi amostrado em triplicata. Foi feita a média de crescimento bacteriano das 3 placas e pontuada em escala de 5 escores. Após limpeza e desinfecção, no primeiro dia de vazio sanitário, houve efeito da interação da água com o detergente (P<0,05), em que o uso do detergente aumentou a chance de diminuir a contaminação quando usado com água quente, mas não com água fria. Na ausência de detergente, a água fria foi mais eficaz em reduzir a contaminação do que a água quente. Houve, também, efeito da interação do detergente com o desinfetante (P<0,05), em que a presença de ambos foi mais eficaz em reduzir a contaminação do que na sua ausência ou quando apenas um dos dois foi utilizado. No terceiro dia, foi verificado que a ausência de desinfetante diminuiu a chance de reduzir a contaminação (P < 0,0001) em comparação com o uso de detergente. A água quente não representou ganho adicional quando comparada a água fria. As evidências aqui observadas reiteram a importância da lavagem, desinfecção e vazio sanitário na redução da carga bacteriana em creche de suínos. A metodologia usada no presente trabalho pode servir como um sistema simples de monitoria dos processos de lavagem e desinfecção de instalações usadas para criação de suínos. / The colonization by pathogenic microorganisms in nursery pig units is an important factor in the spread and outbreaks of diseases in the herds. Pathogens are mainly controlled by biosecurity measures, such as cleaning, disinfection and downtime on facilities. The present study evaluated the bacterial load after the cleaning and disinfection process, during the three days of vacancy, in two pig nurseries, by the use of contact plates selective for enterobacteria. Data were analyzed considering three factors (water, detergent and disinfectant) in two levels (water: cold / hot, detergent and disinfectant: presence / absence). Were used 4 pen for each treatment, and 3 plates for 4 points of the pen. A mean of the 3 bacterial growths was calculated and scored on a 5 point scale. After cleaning and disinfection, there was no detergent - water effect (P <0.05) with cold water. In the absence of detergent, cold water was more effective in reducing contamination than hot water. There was also an effect of the interaction of detergent and disinfectant (P <0.05), where a presence of both was more effective in reducing contamination than in its absence or when only one was used. On the third day, it was found that the absence of disinfectant decreased a chance of reducing contamination (P <0.0001) when compared with the use of detergent. Addition of detergent decreased the chance of contamination when combined with disinfectant, as detergent helps in removing dirt and exposes bacteria which were protected by organic matter and biofilms. The use of hot water did not how advantage when compared with cold water. As there was a fall on contamination between the 1st and 3rd day, the time of action of the disinfectant must be considered to calculate the time of vacancy to permit the action on surviving microorganisms. The results of the present work reinforce the importance of cleaning, disinfection and downtime to reduce bacterial load in swine nurseries. The methodology used in this work may serve as a practical system for monitoring cleaning and disinfection of pig facilities.
84

Atividade antioxidante, compostos fenólicos totais e cor em abacate 'hass' submetido a diferentes tratamentos físicos /

Tremocoldi, Maria Augusta, 1983- January 2011 (has links)
Orientador: Rogério Lopes Vieites / Banca: Erica Regina Daiuto / Banca: Severino Matias de Alencar / Resumo: O presente trabalho teve por objetivo determinar a atividade antioxidante, compostos fenólicos totais e cor em abacate 'Hass' submetido ao tratamento térmico, radiação gama e ultravioleta. Após a colheita, os frutos foram selecionados para tornar o lote homogêneo. Foi realizada a caracterização do fruto verde e amadurecido quanto a acidez titulável, pH, umidade, teor de lipídios, cinzas (minerais), proteína (nitrogênio bruto), açúcar total e coloração. Foram realizados 3 experimentos com frutos recém colhidos. Experimento I: imersão dos frutos em água a 45ºC por 5, 10, 15 e 20 minutos; Experimento II: radiação gama nas doses 0,2; 0,4; 0,6 e 1,0kGy e Experimento III: radiação ultravioleta (UVC) por 5, 10, 15 e 20 minutos. Após os tratamentos, os frutos foram armazenados em temperatura ambiente (21ºC±1 e 70±5% de UR) e refrigerado (10ºC±1 e 90±5% de UR). Os frutos foram analisados quanto à capacidade antioxidante pelo método DPPH e compostos fenólicos totais aos 0, 3, 9 e 12 dias. A coloração foi avaliada aos 0, 3, 6, 9, 12 e 15 dias. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey ao nível de 1% de probabilidade. Nas condições em que os experimentos foram realizados, pode-se concluir que os frutos do tratamento testemunha e mantidos sob refrigeração apresentaram maior capacidade antioxidante e teor de compostos fenólicos totais ao longo do período de armazenamento; o tratamento térmico por 5 e 10 minutos foi efetivo na manutenção da capacidade antioxidante e dos compostos fenólicos; a dose de 0,6kGy não foi efetiva na manutenção da capacidade antioxidante; a radiação ultravioleta (UV-C) não manteve a capacidade antioxidante dos frutos, no entanto ocasionou aumento na quantidade de compostos fenólicos; o tratamento térmico e a radiação ultravioleta não afetaram a coloração da polpa / Abstract: This study aimed to determine the antioxidant activity, total phenolic compounds and color in avocado 'Hass' submitted to heat treatment, gamma and ultraviolet radiation. After harvest, fruits were selected to make the homogeneous portion. The characterization was performed of the green fruit and mature as acidity, pH, moisture, lipids, ash (minerals), protein (nitrogen gross), total sugar and coloring. 3 experiments were performed with freshly harvested fruits. Experiment I: immersion of fruits in water at 45 ° C for 5, 10, 15 and 20 minutes; Experiment II: gamma radiation doses 0.2, 0.4, 0.6 and 1.0 kGy and Experiment III: ultraviolet radiation (UV-C) for 5, 10, 15 and 20 minutes. After treatments, fruits were stored at room temperature (21±1ºC and 70±5% HR) and refrigeration (10ºC±1 and 90±5% HR). The fruits were analyzed for their antioxidant capacity by DPPH method and phenolic compounds at 0, 3, 9 and 12 days. The color was measured at 0, 3, 6, 9, 12 and 15 days. Data were subjected to analysis of variance and mean comparison using Tukey's test at 1% probability. In conditions where the experiments were performed, one can conclude that the fruits of control treatment and kept under refrigeration had higher antioxidant capacity and content of phenolic compounds during the storage period, the heat treatment for 5 and 10 minutes was effective the maintenance of antioxidant capacity and phenolic compounds, the dose of 0.6 kGy was not effective in maintenance the antioxidant capacity, ultraviolet radiation (UV-C) did not maintain the antioxidant capacity of fruits, however caused an increase in the content of phenolic compounds, heat treatment and ultraviolet radiation did not affect the pulp color / Mestre
85

Sistemas prediais de aquecimento de água a gás: Parâmetros de dimensionamento e gerenciamento / Building systems of gas water heating: parameters of design and management

Jose Jorge Chaguri Junior 30 March 2009 (has links)
Os sistemas prediais de aquecimento de água são responsáveis por uma parcela significativa no consumo de energia do país, sendo que a eficiência do uso desta energia está relacionada com a qualidade dos projetos e de alternativas construtivas que possibilitam racionalizar o uso dos recursos naturais. Com a tendência de incorporação da medição individualizada de água e do aquecimento solar, algumas concepções de projetos hidráulicos foram alteradas, entre elas, a introdução de sistemas centrais coletivos de aquecimento de água no setor residencial. Porém, os métodos de dimensionamento destes sistemas são restritos à determinação do estado estático da infraestrutura e dos equipamentos envolvidos. Conhecendo as características de uso da população é possível introduzir sistemas de monitoração e gestão que alterem o dimensionamento das centrais de aquecimento, conforme a demanda instantânea, gerando reduções de perdas térmicas. Este trabalho consiste em analisar as variáveis de um sistema predial de aquecimento central a gás e o impacto na implantação de sistemas de monitoração e gestão. / The building systems of water heating are responsible for a significant parcel of energy consumption in country, and the efficiency of use of this energy is related to the quality of projects and constructive alternatives that allow rationalizing the use of natural resources. With the trend of incorporating the measurement of individual water and solar heating, some conceptions of hydraulic projects were changed including the introduction of collective central heating water in the residential sector. However, the methods of these systems are restricted to the determination of the static state of infrastructure and equipment involved. Knowing the characteristics of populations use is possible to introduce systems of monitoring and management to change the design of central heating as the instant demand, causing reductions in thermal losses.
86

Utilização da energia solar em sistemas de aquecimento de água residencial / The solar energy uses in home water heater systems

Basso, Luiz Henrique 27 June 2008 (has links)
Made available in DSpace on 2017-07-10T19:24:30Z (GMT). No. of bitstreams: 1 LUIZ HENRIQUE BASSO.pdf: 2154844 bytes, checksum: 4e4e8b56f9c25a2ef13e0c7368a8197b (MD5) Previous issue date: 2008-06-27 / The awareness of the importance of the environment has stimulated the study of new energy sources renewed and less pollutant. Amongst these sources, solar energy stands alone for being perennial and clean. The use of solar energy in systems of residential water heating, instead of the electric shower, can compliment the economy of electric energy, based of the Brazilian energy matrix. To know all the factors that influence the operation of a system of water heating by solar energy is important in the determination of its economic viabilities, techniques and, distribution targeting in urban and agricultural residences. To evaluate equipment of water heating for solar energy in the region west of the Paraná, an archetype with similar characteristics to equipment used in residences for two inhabitants was built, to function with natural circulation or thermosiphon and without help of a complementary heating system. The room temperature and the speed of the wind were also evaluated, verifying its influence in the heating system. The equipment revealed technical viability, reaching the minimum temperature of 35°C for shower, whenever the solar radiation was above the 3500 W.m-2, for the majority of the studied days. The system operated without interruptions and it did not need maintenance, except for the monthly glass cleaning. Economic viability was clearly demonstrated since the useful life of the equipment exceeded the period of use to gain its investment. / A conscientização da importância do meio ambiente tem incentivado o estudo de novas fontes energéticas renováveis e menos poluentes. Dentre essas fontes, a energia solar se destaca por ser perene e limpa. A utilização da energia solar em sistemas de aquecimento de água residenciais, pela substituição do chuveiro elétrico, pode colaborar com a economia de energia elétrica, base da matriz energética brasileira. Conhecer todos os fatores que influenciam a operação de um sistema de aquecimento de água por energia solar é importante na determinação de suas viabilidades técnica e econômica, visando sua difusão em residências urbanas e rurais. Para avaliar um equipamento de aquecimento de água por energia solar na região oeste do Paraná, construiu-se um protótipo com características similares a um equipamento utilizado em residências para dois habitantes, para funcionar com circulação natural ou termossifão e sem auxílio de sistema de aquecimento complementar. A temperatura ambiente e a velocidade do vento também foram avaliadas, verificando-se sua influência no sistema de aquecimento. O equipamento mostrou-se viável tecnicamente, alcançando a temperatura mínima de 35°C para banho, sempre que a radiação solar foi superior a 3500 W.m-2, o que aconteceu para a maioria dos dias estudados. O sistema operou sem interrupções e não necessitou de manutenção, exceto pela limpeza mensal do vidro. Constatou-se a viabilidade econômica, já que a vida útil do equipamento é superior ao período de retorno do investimento.
87

Utilização da energia solar em sistemas de aquecimento de água residencial / The solar energy uses in home water heater systems

Basso, Luiz Henrique 27 June 2008 (has links)
Made available in DSpace on 2017-05-12T14:47:49Z (GMT). No. of bitstreams: 1 LUIZ HENRIQUE BASSO.pdf: 2154844 bytes, checksum: 4e4e8b56f9c25a2ef13e0c7368a8197b (MD5) Previous issue date: 2008-06-27 / The awareness of the importance of the environment has stimulated the study of new energy sources renewed and less pollutant. Amongst these sources, solar energy stands alone for being perennial and clean. The use of solar energy in systems of residential water heating, instead of the electric shower, can compliment the economy of electric energy, based of the Brazilian energy matrix. To know all the factors that influence the operation of a system of water heating by solar energy is important in the determination of its economic viabilities, techniques and, distribution targeting in urban and agricultural residences. To evaluate equipment of water heating for solar energy in the region west of the Paraná, an archetype with similar characteristics to equipment used in residences for two inhabitants was built, to function with natural circulation or thermosiphon and without help of a complementary heating system. The room temperature and the speed of the wind were also evaluated, verifying its influence in the heating system. The equipment revealed technical viability, reaching the minimum temperature of 35°C for shower, whenever the solar radiation was above the 3500 W.m-2, for the majority of the studied days. The system operated without interruptions and it did not need maintenance, except for the monthly glass cleaning. Economic viability was clearly demonstrated since the useful life of the equipment exceeded the period of use to gain its investment. / A conscientização da importância do meio ambiente tem incentivado o estudo de novas fontes energéticas renováveis e menos poluentes. Dentre essas fontes, a energia solar se destaca por ser perene e limpa. A utilização da energia solar em sistemas de aquecimento de água residenciais, pela substituição do chuveiro elétrico, pode colaborar com a economia de energia elétrica, base da matriz energética brasileira. Conhecer todos os fatores que influenciam a operação de um sistema de aquecimento de água por energia solar é importante na determinação de suas viabilidades técnica e econômica, visando sua difusão em residências urbanas e rurais. Para avaliar um equipamento de aquecimento de água por energia solar na região oeste do Paraná, construiu-se um protótipo com características similares a um equipamento utilizado em residências para dois habitantes, para funcionar com circulação natural ou termossifão e sem auxílio de sistema de aquecimento complementar. A temperatura ambiente e a velocidade do vento também foram avaliadas, verificando-se sua influência no sistema de aquecimento. O equipamento mostrou-se viável tecnicamente, alcançando a temperatura mínima de 35°C para banho, sempre que a radiação solar foi superior a 3500 W.m-2, o que aconteceu para a maioria dos dias estudados. O sistema operou sem interrupções e não necessitou de manutenção, exceto pela limpeza mensal do vidro. Constatou-se a viabilidade econômica, já que a vida útil do equipamento é superior ao período de retorno do investimento.
88

Assessing the effects of the solar water heaters programme on the socio-economic development of the Mbombela Local Municipality residents, Mpumalanga Province, Republic of South Africa

Khoza, Vusumuzi Patrick January 2016 (has links)
Thesis (MPA.) --University of Limpopo, 2016 / Refer to the document
89

Life on the margins : the autobiographical fiction of Charles Bukowski

Bigna, Daniel, Humanities & Social Sciences, Australian Defence Force Academy, UNSW January 2005 (has links)
Charles Bukowski devoted his writing career to turning his own life into poetry and prose. In poems and stories about his experiences as one of the working poor in post war America, and in those depicting his experiences as a writer of the American underground, Bukowski represents himself as both a literary and social outsider. Bukowski expresses an alternative literary aesthetic through his fictional persona, Henry Chinaski, who struggles to overcome his suffering in a world he finds absurd, and who embarks on a quest for freedom in his youth to which he remains committed all his life. This thesis examines Charles Bukowski's autobiographical fiction with a specific emphasis on five novels and one collection of short stories. In the novels, Post Office (1970), Factotum (1975), Women (1978), Ham on Rye (1982) and Hollywood (1989), and in a number of short stories in the collection Hot Water Music (1983), Bukowski explores different periods of Chinaski???s life with a dark humour, revealing links between Chinaski???s struggle with the absurd and those aspects comprising Bukowski???s alternative aesthetic. The thesis focuses on such aspects of Bukowski???s art as the uncommercial nature of his publishing history, his strong emphasis on literary simplicity, the appearance of the grotesque and Bukowski???s obsession with nonconformity, drinking and sex. These aspects illuminate the distinctive nature of Bukowski???s art and its purpose, which is the transformation of an ordinary life into literature. This thesis argues that Bukowski illuminates possibilities that exist for individuals to create an identity for themselves through aesthetic self-expression. The thesis traces the development of Chinaski's non-conformist personality from Ham on Rye, based on Bukowski's youth in Los Angeles during the Depression, to Hollywood, Bukowski's ironic portrayal of Chinaski's brush with the commercial film industry. Through meeting the many challenges he faced throughout his life with defiance, honesty and an irreverent sense of humour, Bukowski invites readers to identify with his alternative world view. The thesis argues this particular aspect of his writing constitutes his most valuable contribution to twentieth century American fiction.
90

Domestic Heating with Solar Thermal : Studies of Technology in a Social Context and Social Components in Technical Studies

Lundh, Magdalena January 2009 (has links)
Research in solar heating has traditionally focused solely on increasing the system efficiency by improving the technical components. In this thesis the technical methodology and system boundaries are widened to connect the technical aspects with market actors that are highly influential on the implementation of solar technology. The research was focused on how social aspects can be brought into technical studies to improve the understanding of solar heating, and how solar thermal technology can be optimized in a larger energy system. Both heat storage and different system solutions have been investigated. The thesis is built on a number of sub-projects exploring different aspects of solar heating. Improved components and system configurations may result in higher fractional energy savings and thereby make solar energy go from a marginal contribution to be the main energy supplier. Both components and systems are considered in this thesis. The solar heating technology has been shown to work well, also in unique system solutions. Technical possibilities with medium-sized stores for single-family houses and seasonal stores for residential areas are presented. Methods to bring studies of technology and actor studies together are also proposed; domestic hot water use has been modelled based on time-use data, while a multifaceted market situation, in which new system solutions must find their way, has been described by the solar and pellet industries. The complexity of assessing installation and use of a particular heating system in relation to the overall energy system is also discussed. Overall, this thesis shows that successful use of solar heating does not only come down to proper technical solutions, but also depends on the interaction between technology and market actors. A widened perspective, including the social context in which the heating system appears, is then essential. This thesis constitutes a step in that direction.

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