51 resultados para Design Methodologies
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MultiBand OFDM (MB-OFDM) UWB [1] is a short-range promising wireless technology for high data rate communications up to 480 Mbps. In this paper, we have designed and implemented in an Virtex-6 FPGA an MB-OFDM UWB receiver for the highest data rate of 480 Mbps. To test the system, we have also implemented an MB-OFDM transmitter and an AWGN generator in VHDL and determined the bit error rates at the receiver running in an FPGA.
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Formaldehyde (FA) ranks 25th in the overall U.S. chemical production, with more than 5 million tons produced each year. Given its economic importance and widespread use, many people are exposed to FA occupationally. Recently, based on the correlation with nasopharyngeal cancer in humans, the International Agency for Research on Cancer (IARC) confirmed the classification of FA as a Group I substance. Considering the epidemiological evidence of a potential association with leukemia, the IARC has concluded that FA can cause this lymphoproliferative disorder. Our group has developed a method to assess the exposure and genotoxicity effects of FA in two different occupational settings, namely FAbased resins production and pathology and anatomy laboratories. For exposure assessment we applied simultaneously two different techniques of air monitoring: NIOSH Method 2541 and Photo Ionization Detection Equipment with simultaneously video recording. Genotoxicity effects were measured by cytokinesis-blocked micronucleus assay in peripheral blood lymphocytes and by micronucleus test in exfoliated oral cavity epithelial cells, both considered target cells. The two exposure assessment techniques show that in the two occupational settings peak exposures are still occurring. There was a statistical significant increase in the micronucleus mean of epithelial cells and peripheral lymphocytes of exposed individuals compared with controls. In conclusion, the exposure and genotoxicity effects assessment methodologies developed by us allowed to determine that these two occupational settings promote exposure to high peak FA concentrations and an increase in the micronucleus mean of exposed workers. Moreover, the developed techniques showed promising results and could be used to confirm and extend the results obtained by the analytical techniques currently available.
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Low-density parity-check (LDPC) codes are nowadays one of the hottest topics in coding theory, notably due to their advantages in terms of bit error rate performance and low complexity. In order to exploit the potential of the Wyner-Ziv coding paradigm, practical distributed video coding (DVC) schemes should use powerful error correcting codes with near-capacity performance. In this paper, new ways to design LDPC codes for the DVC paradigm are proposed and studied. The new LDPC solutions rely on merging parity-check nodes, which corresponds to reduce the number of rows in the parity-check matrix. This allows to change gracefully the compression ratio of the source (DCT coefficient bitplane) according to the correlation between the original and the side information. The proposed LDPC codes reach a good performance for a wide range of source correlations and achieve a better RD performance when compared to the popular turbo codes.
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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica
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Water covers over 70% of the Earth's surface, and is vital for all known forms of life. But only 3% of the Earth's water is fresh water, and less than 0.3% of all freshwater is in rivers, lakes, reservoirs and the atmosphere. However, rivers and lakes are an important part of fresh surface water, amounting to about 89%. In this Master Thesis dissertation, the focus is on three types of water bodies – rivers, lakes and reservoirs, and their water quality issues in Asian countries. The surface water quality in a region is largely determined both by the natural processes such as climate or geographic conditions, and the anthropogenic influences such as industrial and agricultural activities or land use conversion. The quality of the water can be affected by pollutants discharge from a specific point through a sewer pipe and also by extensive drainage from agriculture/urban areas and within basin. Hence, water pollutant sources can be divided into two categories: Point source pollution and Non-point source (NPS) pollution. Seasonal variations in precipitation and surface run-off have a strong effect on river discharge and the concentration of pollutants in water bodies. For example, in the rainy season, heavy and persistent rain wash off the ground, the runoff flow increases and may contain various kinds of pollutants and, eventually, enters the water bodies. In some cases, especially in confined water bodies, the quality may be positive related with rainfall in the wet season, because this confined type of fresh water systems allows high dilution of pollutants, decreasing their possible impacts. During the dry season, the quality of water is largely related to industrialization and urbanization pollution. The aim of this study is to identify the most common water quality problems in Asian countries and to enumerate and analyze the methodologies used for assessment of water quality conditions of both rivers and confined water bodies (lakes and reservoirs). Based on the evaluation of a sample of 57 papers, dated between 2000 and 2012, it was found that over the past decade, the water quality of rivers, lakes, and reservoirs in developing countries is being degraded. Water pollution and destruction of aquatic ecosystems have caused massive damage to the functions and integrity of water resources. The most widespread NPS in Asian countries and those which have the greatest spatial impacts are urban runoff and agriculture. Locally, mine waste runoff and rice paddy are serious NPS problems. The most relevant point pollution sources are the effluents from factories, sewage treatment plant, and public or household facilities. It was found that the most used methodology was unquestionably the monitoring activity, used in 49 of analyzed studies, accounting for 86%. Sometimes, data from historical databases were used as well. It can be seen that taking samples from the water body and then carry on laboratory work (chemical analyses) is important because it can give an understanding of the water quality. 6 papers (11%) used a method that combined monitoring data and modeling. 6 papers (11%) just applied a model to estimate the quality of water. Modeling is a useful resource when there is limited budget since some models are of free download and use. In particular, several of used models come from the U.S.A, but they have their own purposes and features, meaning that a careful application of the models to other countries and a critical discussion of the results are crucial. 5 papers (9%) focus on a method combining monitoring data and statistical analysis. When there is a huge data matrix, the researchers need an efficient way of interpretation of the information which is provided by statistics. 3 papers (5%) used a method combining monitoring data, statistical analysis and modeling. These different methods are all valuable to evaluate the water quality. It was also found that the evaluation of water quality was made as well by using other types of sampling different than water itself, and they also provide useful information to understand the condition of the water body. These additional monitoring activities are: Air sampling, sediment sampling, phytoplankton sampling and aquatic animal tissues sampling. Despite considerable progress in developing and applying control regulations to point and NPS pollution, the pollution status of rivers, lakes, and reservoirs in Asian countries is not improving. In fact, this reflects the slow pace of investment in new infrastructure for pollution control and growing population pressures. Water laws or regulations and public involvement in enforcement can play a constructive and indispensable role in environmental protection. In the near future, in order to protect water from further contamination, rapid action is highly needed to control the various kinds of effluents in one region. Environmental remediation and treatment of industrial effluent and municipal wastewaters is essential. It is also important to prevent the direct input of agricultural and mine site runoff. Finally, stricter environmental regulation for water quality is required to support protection and management strategies. It would have been possible to get further information based in the 57 sample of papers. For instance, it would have been interesting to compare the level of concentrations of some pollutants in the diferente Asian countries. However the limit of three months duration for this study prevented further work to take place. In spite of this, the study objectives were achieved: the work provided an overview of the most relevant water quality problems in rivers, lakes and reservoirs in Asian countries, and also listed and analyzed the most common methodologies.
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A figura do iluminador (lighting designer) surge nesta dissertação como ponto de partida para um esboço de estudo acerca do autor do desenho de luz no espectáculo teatral em Portugal. Baseámo-nos num dos mais conceituados iluminadores (lighting designer) portugueses, Orlando Worm, para pesquisarmos o que o próprio trouxe aos novos designers de luz que continuam a percorrer um longo e, por vezes, solitário caminho nesta arte criativa. Considerámos para tal tecnologias criadas entre as décadas de 30 a 70 por alguns dos maiores nomes ligados à matéria: Stanley McCandless, Frederick Bentham, Richard Pilbrow e Francis Reid. Estes autores servem-nos como ponto de partida para depois indagarmos se a partir da década de 80 se utiliza algum destes métodos. Ao reflectir acerca destas tecnologias e da própria experiência de Orlando Worm, pretende-se concluir que o trabalho de desenho de luz é, de facto, um trabalho criativo e artístico, na medida em que a figura do iluminador (lighting designer) tem, ou deve ter, um contributo activo no processo teatral.
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Dissertação de natureza Científica para obtenção do grau de Mestre na Área de Especialização de Estruturas
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Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Educação Artística, na Especialização de Artes Plásticas na Educação
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Objectives - Identify radiographers’ postures during frequent mammography procedures related to the mammography equipment and patient characteristics. Methods - A postural task analysis was performed using images acquired during the simulation of mammography positioning procedures. Simulations included craniocaudal/(CC) and mediolateral-oblique/(MLO) positioning in three different settings: radiographers and patients with similar statures, radiographers smaller than the patients and radiographers taller than the patients. Measurements of postural angles were performed by two raters using adequate software and classified according to the European Standard EN1005-4:2005 + A1:2008. Results - The simulations revealed that the most awkward posture in mammography is during the positioning of MLO projection in short-stature patients. Postures identified as causing work-related musculoskeletal disorder (WRMSD) risk were neck extension, arms elevated and the back stooped, presenting angles of 87.2, 118.6 and 63.6, respectively. If radiographers were taller than patients, then the trunk and arm postures were not acceptable. Conclusions - Working in a mammography room leads to awkward postures that can have an impact on radiographers’ health, namely WRMSDs. The results in this study showed that there are non-acceptable postures associated with frequent working procedures in mammography. MLO is the most demanding procedure for radiographer postures and may be related to WRMSDs. Mammography devices should be redesigned considering adjustability for radiographers. Main Messages: • Mammography constraints for radiographers in mammography procedures have not been well studied. • Performing mammography leads to awkward postures that can impact radiographers’ health. • MLO, the most demanding procedure for radiographers, is possibly related to WRMSDs.
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To become an open to outer space, the "museum" acquired new forms and new expressions. The complexity of museological activity thus leads to new representations that alter the initial image of the museum as a building with objects. Their 'boundaries' are now less sharp, not only in relation to the spatial relationship, but also to its temporal dimension, creating an additional challenge which is the recognition of the museum itself. The design, while transdisciplinary activity, thereby assumes a key role in the communication of the museums in its visual representation and recognition of their action. The present study results from a survey conducted in 2010 to 364 Portuguese museums (from a universe of 849 museums), presenting an analysis to its base elements of visual expression of identity (name, logo, symbol, and color).
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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica
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Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Audiovisual e Multimédia.
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O presente Relatório de Estágio tem como objecto de pesquisa a concepção e monitorização de duas Oficinas de Teatro dirigidas a dois grupos de mulheres constituídos, respectivamente, por estudantes universitárias e desempregadas. O estágio realizou-se entre Novembro/2013 e Junho/2014 na Quarta Parede - Associação de Artes Performativas da Covilhã e inseriu-se nos Empowerment Labs, laboratórios formativos que cruzam artes performativas e ciências sociais na reflexão e intervenção sobre a igualdade de género com foco no desemprego feminino. Este relatório expõe os três momentos do processo do estágio: pesquisa de referenciais teórico-práticos, concepção e monitorização das Oficinas de Teatro e reflexão a partir da prática laboratorial. Na pesquisa de referenciais, essencial para delinear a metodologia operacional e o programa de conteúdos, explorei dimensões como o feminismo e a igualdade de género, e procurei compreender de que forma o empowerment, a pedagogia de Paulo Freire e as metodologias do teatro aplicado serviam os objectivos do meu trabalho. A realização das oficinas foi o momento de experimentar as metodologias e o programa delineado. Tendo a igualdade de género como temática unificadora, o empowerment através da arte como objectivo maior e o teatro aplicado como base metodológica, as oficinas inserem-se nos processos de educação não-formal aplicados ao incremento de recursos intelectuais, emocionais, sociais, expressivos e criativos e, neste caso específico, à ampliação da consciência de género. Neste sentido, as oficinas desenvolveram uma abordagem metodológica processual, participativa e multidisciplinar, orientada para a pesquisa performativa, primeiro de uma dramaturgia individual, depois de uma dramaturgia do colectivo e, por fim, de uma dramaturgia orientada para a igualdade de género. O conceito de “dramaturgia” surge aqui no sentido metodológico do pachwork (trabalho com retalhos) e do sampling (recolha e transformação de materiais), relevante sobretudo na última fase, dedicada à construção colectiva de um exercício performativo apresentado publicamente.
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Dissertação de Natureza Científica para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Hidráulica
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This article addresses the problem of obtaining reduced complexity models of multi-reach water delivery canals that are suitable for robust and linear parameter varying (LPV) control design. In the first stage, by applying a method known from the literature, a finite dimensional rational transfer function of a priori defined order is obtained for each canal reach by linearizing the Saint-Venant equations. Then, by using block diagrams algebra, these different models are combined with linearized gate models in order to obtain the overall canal model. In what concerns the control design objectives, this approach has the advantages of providing a model with prescribed order and to quantify the high frequency uncertainty due to model approximation. A case study with a 3-reach canal is presented, and the resulting model is compared with experimental data. © 2014 IEEE.