914 resultados para Cascas (Engenharia)


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A descrição do papel da medicina no Livro III da República pode facilmente deixar o leitor constrangido. O trecho defende que a medicina deveria se espelhar nas práticas do tempo de Asclépio. Neste tempo, a medicina tinha um papel político de não prolongar a vida dos cidadãos tomados pela doença, nem deixá-los procriar. Frente a estas declarações, surgiram várias interpretações que vão desde o totalitarismo de Popper até a ironia de Strauss. Para uma melhor compreensão do texto, seria necessária a interlocução com a medicina hipocrática e com as práticas médicas do tempo dos séculos V e IV aEN. Contudo, a passagem em questão não se reduz ao contexto histórico, mas apresenta uma crítica válida ainda na atualidade. _______________________________________________________________________________ ABSTRACT

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O conhecimento é infinito e tem poderes mágicos: permite-nos pensar mais e melhor e crescer, como seres humanos; liberta-nos da ignorância e dá-nos autonomia para decidirmos, de acordo com os nossos valores e os nossos critérios; capacita-nos a participar, de forma mais qualificada e mais transformadora, naquilo que determina as nossas vidas e torna-nos mais iguais; é um legado de todas as gerações que nos precederam e deverá estar à disposição de todas as que nos sucederem; é um património eterno, que não se gasta com o uso e não se subtrai devido à partilha. O conhecimento é a essência da humanidade e é um direito de todos os seres humanos.

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Droughts surfaced in 1877 as a crucial problem for the birthing Brazilian nation. Engineers, who formed the country's technical and scientific elite, took it upon themselves to study, understand and fight the problem through planned actions of intervention on space. This work, based on proposals and discussions contained in engineering magazines and reports, aims to provide elements for the comprehension of how these systematized actions against droughts, in the Iate nineteenth and early twentieth century, contributed to spatial analysis and the formation of a (then-inexistent) regional and territorial planning discipline in Brazi!. Engineers, by taking up the position of masterminds in the country's modernization, guaranteed for themselves personal economic stability, social prestige and political power. By understanding nature, either as a resource to be exploited or an adversary to national progress, they contributed to the delimitation of the region now known as the Northeast. By seeking to understand the drought phenomenon, they created knowledge about the space they sought to intervene on; by constructing their projects amid political and economical difficulty, they changed the organizational structures of cities and country in the northeast. The proposals for açudes (Iarge water reservoirs) allowed the fixation of population and the resistance against droughts; the roads - railroads and automotive roadways - connected the sertão to the capitais and the coast, speeding up help to the affected populations during droughts and allowing the circulation of goods so as to strengthen the local economies in normal rimes. The adopted practices and techniques, adapted from foreign experience and developed through trial and improvement, were consolidated as an eminently spatial intervention course, even if a theoretical body of regional or territorial planning wasn't formed in Brazil. Regional Planning proper was first applied in the country in the Northeast itself, in the 1950s, based off an economical view of reality in order to achieve development. The engineer's work prior tothat date, however, cannot be dlsconsldered. It was proved that, despite facing financial and political hurdles, engineers had a profound commitment to the problem and intended to act systematically to transform the economical and social relations in the region, in order to be victorious in their struggle against droughts

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Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL

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Mestrado em Arquitectura Paisagista - Instituto Superior de Agronomia - UL

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To produce porcelain tiles fluxing agents are used in order to obtain a liquid phase during firing. This liquid phase fills the pores decreasing porosity, water absorption and contributes to material densification. In the porcelain tiles industry, feldspar is the main flux material used, with quantities ranging between 35 and 50%. Studies focus on the discovery of materials with flux characteristics that can reduce the consumption of feldspar by porcelain tiles industry. In this context, the coffee husk ashes, a residue obtained when coffee husks are burned to produce heat for the dryers during the processing of the green fruit, have as main chemical constituents potassium, calcium and magnesium, giving them characteristics of fluxing material. Brazil is the largest coffee producer in the world and is responsible for over 30% of the world s production. In this work a physical treatment of coffee husk ash was carried out in order to eliminate the organic matter and, after this, two by-products were obtained: residual wastes R1 and R2. Both residues were added separately as single fluxes and also in association with feldspar in mixtures with raw materials collected in a porcelain industry located in Dias d Ávila-Ba. The addition of these residues aimed to contribute to the reduction of the consumption of feldspar in the production of porcelain tiles. Specimens were produced with dimensions of 60 mm x 20 mm x 6 mm in an uniaxial die with compacting pressure of 45 MPa. The samples were heated to a temperature of 1200 °C, for 8 minutes. Tests were performed to characterize the raw materials by XRF, XRD, particle size analysis, DTA and TGA and, additionally, the results of the physical properties of water absorption, apparent porosity, linear shrinkage, density, dilatometry, flexural strength and SEM of sintered body were analyzed. Additions of less than 8% of the residue R1 contributed to the decrease of porosity, but the mechanical strength of the samples was not satisfactory. Additions of 5% the R2 residue contributed significantly to decrease the water absorption and apparent porosity, and also to increase the mechanical strength. Samples with addition of feldspar associated with the R2 residue, in proportions of 6.7% of R2 and 6.7% of feldspar, led to results of water absorption of 0.12% and mechanical strength of 46 MPa, having parameters normalized to the manufacture of porcelain stoneware tiles

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Mestrado em Economia e Gestão de Ciência e Tecnologia

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Actually in the oil industry biotechnological approaches represent a challenge. In that, attention to metal structures affected by electrochemical corrosive processes, as well as by the interference of microorganisms (biocorrosion) which affect the kinetics of the environment / metal interface. Regarding to economical and environmental impacts reduction let to the use of natural products as an alternative to toxic synthetic inhibitors. This study aims the employment of green chemistry by evaluating the stem bark extracts (EHC, hydroalcoholic extract) and leaves (ECF, chloroform extract) of plant species Croton cajucara Benth as a corrosion inhibitor. In addition the effectiveness of corrosion inhibition of bioactive trans-clerodane dehydrocrotonin (DCTN) isolated from the stem bark of this Croton was also evaluated. For this purpose, carbon steel AISI 1020 was immersed in saline media (3,5 % NaCl) in the presence and absence of a microorganism recovered from a pipeline oil sample. Corrosion inhibition efficiency and its mechanisms were investigated by linear sweep voltammetry and electrochemical impedance. Culture-dependent and molecular biology techniques were used to characterize and identify bacterial species present in oil samples. The tested natural products EHC, ECF and DCTN (DMSO as solvent) in abiotic environment presented respectively, corrosion inhibition efficiencies of 57.6% (500 ppm), 86.1% (500 ppm) and 54.5% (62.5 ppm). Adsorption phenomena showed that EHC best fit Frumkin isotherm and ECF to Temkin isotherm. EHC extract (250 ppm) dissolved in a polar microemulsion system (MES-EHC) showed significant maximum inhibition efficiency (93.8%) fitting Langmuir isotherm. In the presence of the isolated Pseudomonas sp, EHC and ECF were able to form eco-compatible organic films with anti-corrosive properties

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Testar software é uma das atividades que faz parte do desenvolvimento de software, e tem como objetivo apresentar evidências de confiabilidade contribuindo para uma maior qualidade do software. Esta atividade consome uma parte significativa do esforço de um projeto de desenvolvimento de software, sempre com o objetivo de encontrar erros antes da fase de manutenção, pois o custo de correção nesta fase pode ser até 100 vezes superior ao custo de correção na fase de conceção. Para auferir mais qualidade ao software, este pode ser certificado por uma norma de qualidade. As normas fornecem processos consistentes, rigorosos e uniformes para o desenvolvimento de software sempre com o objetivo de garantir qualidade ao software. As normas têm um papel importante na definição dos requisitos de teste, casos de teste e relatórios de teste que contemplam a atividade de testes permitindo elaborar um plano de testes mais rigoroso. Como o processo de testes é complexo no desenvolvimento de software, as ferramentas de automatização de testes de software permitem reduzir tempo, recursos e consequentemente os custos para a organização. A automatização deverá ser capaz de produzir os mesmos resultados obtidos através de um processo de testes manual, evidenciando sempre o resultado do teste. Deve também permitir a realização de testes sistemáticos e paralelos em diferentes ambientes de teste, sem o aumento do tempo e de recursos humanos. Nesta dissertação pretende-se desenvolver uma abordagem automatizada com o software Sikuli para a realização de testes seguindo a norma ISO/IEC 25051 para certificação de software. Depois da criação da abordagem e a respetiva criação de testes, é necessário validar a capacidade desta abordagem em comparação com uma abordagem de testes manuais.

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A modernização urbana do que se verificou nas principais cidades urbanas no século XIX foi marcada por dois fenómenos importantes. Por um lado pela criação de novas estruturas urbanas, e, por outro pelo desenvolvimento industrial. A concentração fabril contribuiu para o aumento da poluição do ar e criou problemas ambientais numa altura em que a higiene e salubridade dos espaços urbanos assumiam maior importância. Para tentar a poluição fabril ao longo do século XIX foi publicada uma serie de legislação. Por outro lado, os médicos, os químicos e os engenheiros tentaram propor soluções que diminuíssem a poluição provocada pelas fábricas ao mesmo tempo que procuraram implementar na cidade as modernas infraestruturas urbanas. O seu conhecimento do progresso da tecnologia permitiu-lhes compreender melhor a poluição produzida pela máquina a vapor ou por alguns processos industriais e propor soluções O objetivo desta comunicação é, tendo Lisboa como espaço de análise, abordar: os problemas ambientais provocados pelo desenvolvimento industrial; a forma como a legislação, engenheiros e cientistas tentaram controlar e contribuir para a resolução dos problemas ambientais.

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Over the past decade privatised capital city airports in Australia have planned developed a range of non aviation commercial and retail land uses on airport land. Many surrounding municipalities consider this development in conflict with existing regional land use planning. Conversely airport operators are alarmed at continued urban consolidation and encroachment of incompatible regional development. Land use planning within and surrounding Australian capital city airports does not support compatible and integrated land use. It is currently a fragmented process due to: 1) current legislative and policy frameworks; 2) competing stakeholder priorities and interests; and 3) inadequate coordination and disjointed decision-making. This paper will examine privatised Australian airport development and consider three case studies to detail the context of airport and regional land use planning. A series of stakeholder workshops have served to inform the procedural dynamics and relationships between airport and regional decision-making. This exploratory research will assist in informing the knowledge gaps between aviation, airport development and broader urban land use policy. This paper will provide recommendations to enhance approaches to land use planning for airports and adjacent metropolitan regions in Australia and overseas.

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Indoor air quality is a critical factor in the classroom due to high people concentration in a unique space. Indoor air pollutant might increase the chance of both long and short-term health problems among students and staff, reduce the productivity of teachers and degrade the student’s learning environment and comfort. Adequate air distribution strategies may reduce risk of infection in classroom. So, the purpose of air distribution systems in a classroom is not only to maximize conditions for thermal comfort, but also to remove indoor contaminants. Natural ventilation has the potential to play a significant role in achieving improvements in IAQ. The present study compares the risk of airborne infection between Natural Ventilation (opening windows and doors) and a Split-System Air Conditioner in a university classroom. The Wells-Riley model was used to predict the risk of indoor airborne transmission of infectious diseases such as influenza, measles and tuberculosis. For each case, the air exchange rate was measured using a CO2 tracer gas technique. It was found that opening windows and doors provided an air exchange rate of 2.3 air changes/hour (ACH), while with the Split System it was 0.6 ACH. The risk of airborne infection ranged between 4.24 to 30.86 % when using the Natural Ventilation and between 8.99 to 43.19% when using the Split System. The difference of airborne infection risk between the Split System and the Natural Ventilation ranged from 47 to 56%. Opening windows and doors maximize Natural Ventilation so that the risk of airborne contagion is much lower than with Split System.

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Consultoria Legislativa - Área XI - Meio Ambiente e Direito Ambiental, Organização Territorial, Desenvolvimento Urbano e Regional.