892 resultados para Sports facilities -- Heating and ventilation
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We present optical spectra and light curves for three hydrogen-poor superluminous supernovae followed by the Public ESO Spectroscopic Survey of Transient Objects (PESSTO). Time series spectroscopy from a fewdays aftermaximum light to 100 d later shows them to be fairly typical of this class, with spectra dominated by Ca II, MgII, FeII, and Si II, which evolve slowly over most of the post-peak photospheric phase. We determine bolometric light curves and apply simple fitting tools, based on the diffusion of energy input by magnetar spin-down, Ni-56 decay, and collision of the ejecta with an opaque circumstellar shell. We investigate how the heterogeneous light curves of our sample (combined with others from the literature) can help to constrain the possible mechanisms behind these events. We have followed these events to beyond 100-200 d after peak, to disentangle host galaxy light from fading supernova flux and to differentiate between the models, which predict diverse behaviour at this phase. Models powered by radioactivity require unrealistic parameters to reproduce the observed light curves, as found by previous studies. Both magnetar heating and circumstellar interaction still appear to be viable candidates. A large diversity is emerging in observed tail-phase luminosities, with magnetar models failing in some cases to predict the rapid drop in flux. This would suggest either that magnetars are not responsible, or that the X-ray flux from the magnetar wind is not fully trapped. The light curve of one object shows a distinct rebrightening at around 100 d after maximum light. We argue that this could result either from multiple shells of circumstellar material, or from a magnetar ionization front breaking out of the ejecta.
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This is an article on ‘tone’ for the 1360 pages SAGE Encyclopedia "Music in the Social and Behavioral Sciences". This Encyclopedia is considered the first definitive reference resource to take a broad interdisciplinary approach to the nexus between music and the social and behavioral sciences examines how music affects human beings and their interactions in and with the world. The interdisciplinary nature of the work provides a starting place for students to situate the status of music within the social sciences in fields such as anthropology, communications, psychology, linguistics, sociology, sports, political science and economics, as well as biology and the health sciences.
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This paper explores the potential for façade located solar thermal collectors. Building typologies with limited roof space area are highlighted. A relationship exists between hot water consumption and the solar collector area; hence, a literature review of the hot water consumption of different building typologies is conducted. The review showed that there is a paucity of information on the hot water consumption of buildings, primarily attributed to the difficulty in quantifying it. The hot water consumption is typically describedusing liters per capita per day (Lcd) units, with a broad range of values existing, dependent, primarily on the building's function and location. Asimulation-based study is conducted to size solar thermal systems for different buildings and their associated hot water loads. High solar fractions,for buildings with high levels of hot water consumption, could only be achievedby using significantly largercollector surface areas. As a result, façade located solar thermal collectors are required for certain high-rise buildings that aim to provide for their hot water needs using a considerable portion of solar energy.
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Glazed Double Skin Facades (DSF) offer the potential to improve the performance of all-glass building skins, common to commercial office buildings in which full facade glazing has almost become the standard. Single skin glazing results in increased heating and cooling costs over opaque walls, due to lower thermal resistance of glass, and the increased impact of solar gain through it. However, the performance benefit of DSF technology continues to be questioned and its operation poorly understood, particularly the nature of airflow through the cavity. This paper deals specifically with the experimental analysis of the air flow characteristics in an automated double skin façade. The benefit of the DSF as a thermal buffer, and to limit overheating is evaluated through analysis of an extensive set of parameters including air and surface temperatures at each level in the DSF, airflow readings in the cavity and at the inlet and outlet, solar and wind data, and analytically derived pressure differentials. The temperature and air-flow are monitored in the cavity of a DSF using wireless sensors and hot wire anemometers respectively. Automated louvre operation and building set-points are monitored via the BMS. Thermal stratification and air flow variation during changing weather conditions are shown to effect the performance of the DSF considerably and hence the energy performance of the building. The relative pressure effects due to buoyancy and wind are analysed and quantified. This research aims to developed and validate models of DSFs in the maritime climate, using multi-season data from experimental monitoring. This extensive experimental study provides data for training and validation of models.
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Models of ground source heat pump (GSHP) systems are used as an aid for the correct design and optimization of the system. For this purpose, it is necessary to develop models which correctly reproduce the dynamic thermal behavior of each component in a short-term basis. Since the borehole heat exchanger (BHE) is one of the main components, special attention should be paid to ensuring a good accuracy on the prediction of the short-term response of the boreholes. The BHE models found in literature which are suitable for short-term simulations usually present high computational costs. In this work, a novel TRNSYS type implementing a borehole-to-ground (B2G) model, developed for modeling the short-term dynamic performance of a BHE with low computational cost, is presented. The model has been validated against experimental data from a GSHP system located at Universitat Politècnica de València, Spain. Validation results show the ability of the model to reproduce the short-term behavior of the borehole, both for a step-test and under normal operating conditions.
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This paper presents the results from the experimental investigation on heat activated prestressing of Shape Memory Alloy (SMA) wires for active confinement of concrete sections. Active confinement of concrete is found to be much more effective than passive confinement which becomes effective only when the concrete starts to dilate. Active confinement achieved using conventional prestressing techniques often faces many obstacles due to practical limitations. A class of smart materials that has recently drawn attention in civil engineering is the super elastic SMA which has the ability to undergo reversible hysteretic shape change known as the shape memory effect. The shape memory effect of SMAs can be utilized to develop a convenient prestressing technique for active confinement of concrete sections.
In this study a series of experimental tests are conducted to study Heat Activated Prestress (HAP) in SMAs. Three different types of tests are conducted with different loading protocol to determine parameters such as HAP, residual strain after heating and range of strain that can be used for effective active confinement after HAP. Test results show a maximum HAP of about 500 MPa can be achieved after heating and approximately 450MPa is retained at 25oC in specimens pre-strained by 6%. A substantial amount of strain recovery upon unloading and after heating the SMA wires is recorded. About 2.5% elastic strain recovery upon unloading from 6% strain level is observed. In the specimen pre-strained by 6%, a total of 4% strain is recovered when unloaded after heating. A strain range of 3% is found available for effective confinement after HAP. Test results demonstrate that SMAs have unique features that can be intelligently employed in many civil engineering applications including active confinement of concrete sections.
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Na divulgação de qualquer destino turístico é necessário ter em conta diversos fatores. Esta dissertação teve como principal objetivo analisar a procura e a oferta ao nível do turismo desportivo no concelho de Évora. Foi estudado o turismo desportivo no município de Évora, que é um dos maiores destinos turísticos da região Alentejo. Aplicando questionários de maneira a saber qual a opinião dos turistas relativamente a atividades desportivas praticadas neste destino. Foram ainda realizadas duas entrevistas a responsáveis da Câmara Municipal de Évora e ao Diretor de uma empresa de Animação Turística. A falta de estratégia no sector é evidenciada pelo facto dos visitantes não apresentarem como motivação primária a prática de atividades desportivas. Sendo o Turismo e o Desporto sectores económicos de grande importância em termos globais e locais, verificou-se que no concelho de Évora o Turismo Desportivo pode ser um grande agente de desenvolvimento em diversas áreas; Abstract: Sports Tourism in Évora Municipality The disclosure of any tourist destination should be taken into account several factors. This work aimed to analise the demand and supply in terms of sports tourism in Évora municipality. An investigation was made to the city of Évora, which is one of the biggest tourist destinations in Alentejo region, applying questionnaire in order to know the opinion of tourists with regard to sports activities practiced in this destination. They were also carried out two interviews with officials of the Municipality of Évora, and the Director of a Tourism Entertainment company. The lack of strategy in the sector is demonstrated by the fact that visitors do not present as the primary motivation to practice sports activities. Tourism and Sports are sectors of great importance in global and local economy, it was found that in Évora county, Sports Tourism can be a major agent of development in several areas.
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A presente dissertação contempla estudos de reactividade na periferia e no interior do macrociclo corrólico, nomeadamente do 5,10,15- tris(pentafluorofenil)corrol. Nesses estudos foram estabelecidas novas rotas de síntese para a preparação de novos derivados tetrapirrólicos do tipo corrol, alguns deles com potencial aplicação medicinal. Na primeira parte, foi estudado o comportamento de 5,10,15- tris(pentafluorofenil)corrol como componente 2ʌ em reacções de cicloadição de Diels-Alder com hidrocarbonetos aromáticos policíclicos, designadamente antraceno, tetraceno, nafto[2,3-a]pireno e pentaceno. Estas reacções foram efectuadas em aquecimento clássico e com radiação de microondas. Desses estudos concluiu-se que todos os hidrocarbonetos aromáticos considerados, à excepção do nafto[2,3-a]pireno, reagem segundo reacções de Diels-Alder, mas apenas com o pentaceno se obtêm aductos provenientes de reacções de cicloadição [4+4]. Os resultados obtidos em algumas destas reacções levaram a um estudo aprofundado sobre a estabilidade do macrociclo considerado. Este estudo foi efectuado sob condições térmicas, sob a acção da luz e na presença de um agente promotor de radicais. Desses estudos concluiu-se que apenas com aquecimento clássico é possível obter o dímero com o anel ciclooctatetraeno ligado pelas posições C-2, C-2’ e C-18, C-18’ e o dímero assimétrico ligado pelas posições C-2 e C-3’. Na presença de luz ou na presença de agente promotor de radicais obtém-se o dímero simétrico ligado pelas posições C-3 e C-3’. O estudo do mecanismo da reacção de dimerização na presença de luz levou ainda à síntese de um corrol mono-iodado. Foi ainda analisado o comportamento de 5,10,15-tris(pentafluorofenil)corrol e de 5,10,15-tris(pentafluorofenil)corrolatogálio(III)(piridina) na presença de iletos de azometino. Destes estudos resultou o desenvolvimento de novas rotas de síntese para a obtenção de novos derivados do tipo amina e do tipo éter. Na terceira parte, descrevem-se estudos de complexação do 5,10,15- tris(pentafluorofenil)corrol com diferentes sais metálicos por espectrometria de massa. Foram usados como fontes de ionização o Electrospray e o LSIMS. Os resultados obtidos comprovaram que os metalocorróis obtidos na fonte são idênticos aos metalocorróis sintetizados. Na quarta parte deste trabalho foram sintetizados novos conjugados corrolciclodextrina por meio de reacções de substituição nucleófila. A actividade fotodinâmica destes derivados foi avaliada numa linha celular cancerígena. A estrutura dos compostos sintetizados foi estabelecida recorrendo a diversas técnicas espectroscópicas actuais, principalmente espectroscopia de Ressonância Magnética Nuclear (RMN de 1H, 13C e 19F, DEPT, COSY, HSQC, HMBC e NOESY), espectrometria de massa em LSIMS, ESI e MALDI e ainda recorrendo a espectrofotometria de Ultravioleta-Visível (UV-vis).
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O presente trabalho tem como objectivo o estudo, desenvolvimento e aplicações na área da biomecânica de sensores intrínsecos baseados em redes de Bragg em fibras ópticas (FBG). As aplicações são feitas em modelos biomecânicos in vitro tais como: implantes de anca, prótese de joelho, placas de osteossíntese e implantes dentários. A optimização do desenvolvimento de próteses e respectivos elementos de fixação é actualmente dependente da geração e validação experimental de seus modelos computacionais. A validação destes modelos é normalmente feita utilizando-se dados de ensaios não invasivos e invasivos em modelos sintéticos. Em ensaios in vitro os sensores convencionais têm um princípio de funcionamento eléctrico e apresentam por vezes dimensões inadequadas. Existem situações exploradas no presente trabalho, tais como sensoriamento de superfícies irregulares e junções ou ainda análises de deformações internas, onde é recomendável a utilização de sensores FBG, pois apresentam dimensões reduzidas e flexibilidade o que permite efectuar medidas localizadas. O desenvolvimento de um protocolo de utilização de FBG e a sua aplicação no contexto apresentado demonstrou-se mais adequado, pela precisão e segurança futura oferecidas. Foi desenvolvida uma metodologia experimental para medidas de deformações utilizando FBG ao longo de uma placa de osteossíntese metálica aparafusada a um fémur sintético fracturado. Foi efectuada a monitorização da cura do cimento ósseo utilizado como fixador do prato tibial na artroplastia total do joelho através da medida da sua contracção e temperatura. Foi também desenvolvido um sistema refrigerador com resposta às leituras de temperatura com vista a evitar a necrose do osso. Foram efectuados estudos de deformação nesse cimento após a sua cura, como resultado da aplicação de cargas mecânicas estáticas. Foram efectuados estudos da cura de cimento ósseo aplicado a próteses de anca e também de deformações nestas próteses. Foi ainda efectuado o estudo comparativo de vários implantes dentários através da medida da distribuição de deformações como resposta a excitações mecânicas impulsivas. Para a desmodulação das FBG foram inicialmente utilizados sistemas comerciais. Entretanto algumas aplicações não puderam ser implementadas com estes sistemas comerciais devido à baixa reflectividade das FBG utilizadas, mas fundamentalmente devido à necessidade de executar testes com uma taxa de aquisição maior do que os 5 Hz disponíveis (cerca de 15 kHz). Por estes motivos foi desenvolvido um sistema optoelectrónico completo de desmodulação de FBG baseado num filtro sintonizável e que tem como característica principal a alta taxa de aquisição (até 1,2 MHz) mas também se destaca pela facilidade na reconfiguração dos parâmetros de leitura, pela apresentação duma interface de utilizador amigável e pela capacidade de operar com até 5 FBG na mesma fibra óptica.
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In Portugal, it was estimated that around 1.95 Mton/year of wood is used in residential wood burning for heating and cooking. Additionally, in the last decades, burnt forest area has also been increasing. These combustions result in high levels of toxic air pollutants and a large perturbation of atmospheric chemistry, interfere with climate and have adverse effects on health. Accurate quantification of the amounts of trace gases and particulate matter emitted from residential wood burning, agriculture and garden waste burning and forest fires on a regional and global basis is essential for various purposes, including: the investigation of several atmospheric processes, the reporting of greenhouse gas emissions, and quantification of the air pollution sources that affect human health at regional scales. In Southern Europe, data on detailed emission factors from biomass burning are rather inexistent. Emission inventories and source apportionment, photochemical and climate change models use default values obtained for US and Northern Europe biofuels. Thus, it is desirable to use more specific locally available data. The objective of this study is to characterise and quantify the contribution of biomass combustion sources to atmospheric trace gases and aerosol concentrations more representative of the national reality. Laboratory (residential wood combustion) and field (agriculture/garden waste burning and experimental wildland fires) sampling experiments were carried out. In the laboratory, after the selection of the most representative wood species and combustion equipment in Portugal, a sampling program to determine gaseous and particulate matter emission rates was set up, including organic and inorganic aerosol composition. In the field, the smoke plumes from agriculture/garden waste and experimental wildland fires were sampled. The results of this study show that the combustion equipment and biofuel type used have an important role in the emission levels and composition. Significant differences between the use of traditional combustion equipment versus modern equipments were also observed. These differences are due to higher combustion efficiency of modern equipment, reflecting the smallest amount of particulate matter, organic carbon and carbon monoxide released. With regard to experimental wildland fires in shrub dominated areas, it was observed that the largest organic fraction in the samples studied was mainly composed by vegetation pyrolysis products. The major organic components in the smoke samples were pyrolysates of vegetation cuticles, mainly comprising steradienes and sterol derivatives, carbohydrates from the breakdown of cellulose, aliphatic lipids from vegetation waxes and methoxyphenols from the lignin thermal degradation. Despite being a banned practice in our country, agriculture/garden waste burning is actually quite common. To assess the particulate matter composition, the smoke from three different agriculture/garden residues have been sampled into 3 different size fractions (PM2.5, PM2.5-10 and PM>10). Despite distribution patterns of organic compounds in particulate matter varied among residues, the amounts of phenolics (polyphenol and guaiacyl derivatives) and organic acids were always predominant over other organic compounds in the organosoluble fraction of smoke. Among biomarkers, levoglucosan, β-sitosterol and phytol were detected in appreciable amounts in the smoke of all agriculture/garden residues. In addition, inositol may be considered as an eventual tracer for the smoke from potato haulm burning. It was shown that the prevailing ambient conditions (such as high humidity in the atmosphere) likely contributed to atmospheric processes (e.g. coagulation and hygroscopic growth), which influenced the particle size characteristics of the smoke tracers, shifting their distribution to larger diameters. An assessment of household biomass consumption was also made through a national scale survey. The information obtained with the survey combined with the databases on emission factors from the laboratory and field tests allowed us to estimate the pollutant amounts emitted in each Portuguese district. In addition to a likely contribution to the improvement of emission inventories, emission factors obtained for tracer compounds in this study can be applied in receptor models to assess the contribution of biomass burning to the levels of atmospheric aerosols and their constituents obtained in monitoring campaigns in Mediterranean Europe.
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For a greenhouse with a double polyethylene cover, it will be presented a dynamic climate transfer function and an adaptive controller for the air temperature. The model employ data acquired from the outside weather and from the heating and cooling inputs.
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If you're planning to build a new house or replace your heating and cooling system, you may want to consider a geothermal heat pump system. A GHP system can be installed in virtually any area of the country and will save energy and money. This gives tips on how to save money on heat pumps.
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Thesis (Ph. D.)--University of Washington, 1998
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Tese de doutoramento, Biologia (Biologia Molecular), Universidade de Lisboa, Faculdade de Ciências, 2015
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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica