999 resultados para Amostrador automático
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Trabalho de Projeto para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização em Estruturas
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Nos dias de hoje a sociedade exige níveis qualitativos de vida cada vez mais elevados, o que torna prioritária a conceção de sistemas eficientes, não poluidores, económicos e diversificados que permitam uma gestão integrada e racionalizada de recursos tão escasso como é o da água e da energia. Em sistemas de abastecimento de água, o uso de válvulas redutoras de pressão (VRP) visa a uniformização e controlo de pressões, promovendo uma perda de carga localizada que dissipa a energia hidráulica presente através da redução dos valores de pressão a jusante. Estas são fundamentais no controlo e redução de pressão. A utilização de microturbinas é uma alternativa sustentável para o controle de pressão e, simultaneamente, para a produção de energia elétrica. Trata-se de um método de mitigação para controlar as perdas referidas convergindo no âmbito da eficiência energética. Na perspetiva de promover um aproveitamento de energia nas redes de abastecimento de água, o presente trabalho sugere a substituição de válvulas redutoras de pressão (VRP) por microturbinas. Desse modo, apresenta-se um método automático de seleção de (i) local para implementação e (ii) projeto de microturbinas para sistemas de abastecimento de água. Para a modelação do funcionamento dos sistemas hidráulicos recorre-se ao simulador hidráulico EPANET. Esta ferramenta possibilita avaliação de caudais e pressões em todos os pontos da rede durante um determinado intervalo de tempo. A metodologia desenvolvida permite selecionar o local ideal no sistema hidráulico através de uma análise de cada secção conduta-nó escolhendo-se a melhor opção baseada na produção de energia. Depois da localização procede-se à seleção do tipo de turbina (Kaplan, Francis, Pelton e Cross-flow) que vai depender das características do sistema hidráulico. Na etapa seguinte apresenta-se os resultados obtidos pela turbina nomeadamente a produção de energia elétrica anual, o investimento necessário, o tempo de retorno e a rentabilização ao final de um período de 25 anos. Na última etapa da metodologia, de forma avaliar o comportamento do sistema final, realiza-se uma nova simulação da rede mas tendo em conta a introdução da microturbina no local. Apresentam-se alguns casos de estudo que validam a ferramenta desenvolvida. A metodologia desenvolvida é comparada com um caso de estudo real. Em ambos os exemplos simulados a metodologia aplicada permite obter soluções com ganhos energéticos significativos associados ao sistema. Apenas num dos exemplos se observaram que a implementação da microturbina no sistema hidráulico não seria economicamente rentável.
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Nervous system disorders are associated with cognitive and motor deficits, and are responsible for the highest disability rates and global burden of disease. Their recovery paths are vulnerable and dependent on the effective combination of plastic brain tissue properties, with complex, lengthy and expensive neurorehabilitation programs. This work explores two lines of research, envisioning sustainable solutions to improve treatment of cognitive and motor deficits. Both projects were developed in parallel and shared a new sensible approach, where low-cost technologies were integrated with common clinical operative procedures. The aim was to achieve more intensive treatments under specialized monitoring, improve clinical decision-making and increase access to healthcare. The first project (articles I – III) concerned the development and evaluation of a web-based cognitive training platform (COGWEB), suitable for intensive use, either at home or at institutions, and across a wide spectrum of ages and diseases that impair cognitive functioning. It was tested for usability in a memory clinic setting and implemented in a collaborative network, comprising 41 centers and 60 professionals. An adherence and intensity study revealed a compliance of 82.8% at six months and an average of six hours/week of continued online cognitive training activities. The second project (articles IV – VI) was designed to create and validate an intelligent rehabilitation device to administer proprioceptive stimuli on the hemiparetic side of stroke patients while performing ambulatory movement characterization (SWORD). Targeted vibratory stimulation was found to be well tolerated and an automatic motor characterization system retrieved results comparable to the first items of the Wolf Motor Function Test. The global system was tested in a randomized placebo controlled trial to assess its impact on a common motor rehabilitation task in a relevant clinical environment (early post-stroke). The number of correct movements on a hand-to-mouth task was increased by an average of 7.2/minute while the probability to perform an error decreased from 1:3 to 1:9. Neurorehabilitation and neuroplasticity are shifting to more neuroscience driven approaches. Simultaneously, their final utility for patients and society is largely dependent on the development of more effective technologies that facilitate the dissemination of knowledge produced during the process. The results attained through this work represent a step forward in that direction. Their impact on the quality of rehabilitation services and public health is discussed according to clinical, technological and organizational perspectives. Such a process of thinking and oriented speculation has led to the debate of subsequent hypotheses, already being explored in novel research paths.
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Las dificultades a las que los estudiantes se enfrentan y su lucha por dominar los temas, podría aumentar como consecuencia de la inadecuada utilización de materiales de evaluación. Generalmente se encuentran en el aula alumnos que hacen buen uso del material de los cursos y de una manera rápida, mientras que otros presentan dificultades con el aprendizaje del material. Esta situación es fácilmente visto en los resultados de los exámenes, un grupo de estudiantes podrían obtener buenas calificaciones animándoles, mientras que otros obtendrían la mala percepción de que los temas son difíciles, y en algunos casos, obligándolos a abandonar el curso o en otros casos a cambiar de carrera. Creemos que mediante el uso de técnicas de aprendizaje automático, y en nuestro caso la utilización de redes neuronales, sería factible crear un entorno de evaluación que podrían ajustarse a las necesidades de cada estudiante. Esto último disminuiría la sensación de insatisfacción de los alumnos y el abandono de los cursos.
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This study aims to compare the thermal performance of tiles made from recycled material (waste packaging cardboard with aluminized film) with the tiles of fiber and bitumen, fiber cement and red ceramic with the aim of verifying the suitability of tile to be used in hot and humid climate of low latitude. The samples were selected according to the availability from Natal - RN market, as they are sold to the consumers. The methodology was based on studies that used experimental apparatus composed of thermal chambers heated by banks of incandescent bulbs, to analyze the thermal performance of materials. The tiles in the study were submitted to analysis of thermal performance, thermophysical properties and absorptance, using chambers of thermal performance, measuring the thermophysical properties and portable spectrometer, respectively. Comparative analysis of thermal performance between two samples of the recycled material with dimple sizes and different amounts of aluminum were made, in order to verify, if these characteristics had some interference on the thermal performance of them; the results showed no significant performance differences between the samples. The data obtained in chambers of thermal performance and confirmed by statistical analysis, showed, that the tile of recycled material have similar thermal performance to the tile of fiber cement. In addition to these tests was carried out the automatic monitoring of a building covered with tiles of recycled material, to verify its thermal performance in a real situation. The results showed that recycled shingles must be used with technical criteria similar to those used for fiber cement tiles, with regard to the heat gain into the building. Within these criteria should be taken into account local characteristics, especially in regions with hot and humid climate, and its use must be associated, according to the literature, to elements of thermal insulation and use of passive techniques such as vented attics, ceilings and right foot higher
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We propose a study of the mathematical properties of voice as an audio signal -- This work includes signals in which the channel conditions are not ideal for emotion recognition -- Multiresolution analysis- discrete wavelet transform – was performed through the use of Daubechies Wavelet Family (Db1-Haar, Db6, Db8, Db10) allowing the decomposition of the initial audio signal into sets of coefficients on which a set of features was extracted and analyzed statistically in order to differentiate emotional states -- ANNs proved to be a system that allows an appropriate classification of such states -- This study shows that the extracted features using wavelet decomposition are enough to analyze and extract emotional content in audio signals presenting a high accuracy rate in classification of emotional states without the need to use other kinds of classical frequency-time features -- Accordingly, this paper seeks to characterize mathematically the six basic emotions in humans: boredom, disgust, happiness, anxiety, anger and sadness, also included the neutrality, for a total of seven states to identify
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Hoje, há um interesse crescente pela aprendizagem de uma segunda língua, quer seja por razões profissionais ou pessoais. Esta é uma tendência que se vai afirmando num mundo cada vez mais interconectado. Por outro lado, a democratização das tecnologias computacionais torna possível pensar em desenvolver novas técnicas de ensino de línguas mais automatizadas e personalizadas. Esta dissertação teve como objetivo estudar e implementar um conjunto de técnicas de processamento de sinal e de classificação de séries temporais úteis para o desenvolvimento de metodologias do ensino oral com feedback automático. São apresentados resultados preliminares sobre a prestação destas técnicas, e avaliada a viabilidade deste tipo de abordagem.
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This study aimed to determine the concentration and inorganic chemical composition of samples from airborne particulate matter inhaled in fine and coarse fractions. Aerosol samples were collected in 2013 and 2014, from sites located in the cities of Londrina and Maringa, in the state of Paraná, Brazil. The samples were collected daily (24h) in two campaigns: winter and summer. For the collection, was used a dichotomous sampler with quartz fiber filter with 47 mm in size and 2 µm porosity, 97% efficiency, retaining particles of up to 0.3 µm. Quantification of the airborne particulate matter mass was performed by gravimetry method. The results from Londrina to PM2.5 and MP2,5-10 represent, respectively, 29.2% and 70.8% of airborne particulate matter in the winter campaign (2013), 30.9% (PM2.5) and 69.1 % (MP2,5-10) in the summer campaign (2013), and 35.9% (PM2.5) and 64.1% (MP2,5-10) in the winter 2014 campaign. In the city of Maringa, the results presented the percentage of 42.0% (PM2.5) and 58.0% (MP2,5-10) for the winter season (2014), and 28.8% (PM2.5) and 71.2 % (MP2,5-10) for the summer season (2014). The PM2.5/PM10 ratio was on average 0.3, demonstrating that both cities are developing urban areas. Analysis of the major soluble inorganic species in water (NO3-, SO42- and Cl-) associated with MP2,5-10 were quantified by ion chromatography at the LACA Laboratory in the State University of Londrina, with the largest contribution found in all campaigns was to NO3-. The NO3-/SO42- ratios above 1.0 indicate the local traffic contribution. The analysis of metals associated with PM2.5 was carried out by mass spectrometry with inductively coupled plasma (ICP-MS) in the Federal University of Santa Catarina. The Zn, Pb, Cu and Mn concentrations found in all campaigns indicate the contribution of mobile sources to PM2.5. The concentration of BCe in PM2.5 was determined by reflectance, with higher BCe concentrations being found in winter campaigns. In general, Londrina presented the highest concentrations from the species analyzed when compared to Maringá. In addition, the analysis of the air mass trajectories indicated the transportation of pollutants coming mainly from fires in the southeastern region of the country.
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Trabalho de Projeto para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização em Estruturas
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Trabalho de Projeto para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização Estruturas
Resumo:
Trabalho de Projeto para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização em Estruturas
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El reconocimiento de las emociones supone la integración de los aspectos físicos relativos a los movimientos de la musculatura facial, pero también y desde diferentes enfoques se da relevancia al contexto que rodea a dicha expresión en el momento de ser percibida. En la presente investigación se analizó el papel del contexto verbal sobre el reconocimiento de la expresión facial de alegría y tristeza. Participaron 50 sujetos a los que se les pidió que visualizaran expresiones mixtas neutras rodeadas por cinco palabras positivas, negativas o neutras (contexto verbal), que describían la vida de dicha persona (fase I). Posteriormente se les presentaron durante 39 milisegundos expresiones faciales mixtas de alegría o tristeza de las mismas personas que aparecieron en la fase anterior para que decidieran lo más rápido posible si la emoción expresada era de alegría o tristeza (fase II). Los resultados mostraron un peor reconocimiento de la expresión de tristeza respecto a la de alegría cuando el contexto verbal previo era positivo. Por otro lado, la expresión de tristeza se reconoció mejor cuando iba precedida de un contexto verbal negativo respecto a cuando era positivo. Se discuten los resultados dentro del modelo constructivista de la emoción.
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In the last decades, the effects of the air pollution have been increasing, especially in the case of the human health diseases. In order to overcome this problem, scientists have been studying the components of the air. As a part of water-soluble organic compounds, amino acids are present in the atmospheric environment as components of diverse living organisms which can be responsible for spreading diseases through the air. Liquid chromatography is one technique capable of distinguish the different amino acids from each other. In this work, aiming at separating the amino acids found in the aerosols samples collected in Aveiro, the ability of four columns (Mixed-Mode WAX-1, Mixed-Mode HILIC-1, Luna HILIC and Luna C18) to separate four amino acids (aspartic acid, lysine, glycine and tryptophan) and the way the interaction of the stationary phases of the columns with the analytes is influenced by organic solvent concentration and presence/concentration of the buffer, are being assessed. In the Mixed-Mode WAX-1 column, the chromatograms of the distinct amino acids revealed the separation was not efficient, since the retention times were very similar. In the case of lysine, in the elution with 80% (V/V) MeOH, the peaks appeared during the volume void. In the Mixed-Mode HILIC-1 column, the variation of the organic solvent concentration did not affect the elution of the four studied amino acids. Considering the Luna HILIC column, the retention times of the amino acids were too close to each other to ensure a separation among each other. Lastly, the Luna C18 column revealed to be useful to separate amino acids in a gradient mode, being the variation of the mobile phase composition in the organic solvent concentration (ACN). Luna C18 was the column used to separate the amino acids in the real samples and the mobile phase had acidified water and ACN. The gradient consisted in the following program: 0 – 2 min: 5% (V/V) ACN, 2 – 8 min: 5 – 2 % (V/V) ACN, 8 – 16 min: 2% (V/V) ACN, 16 – 20 min: 2 – 20 % (V/V) ACN, 20 – 35 min: 20 – 35 % (V/V) ACN. The aerosols samples were collected by using three passive samplers placed in two different locations in Aveiro and each sampler had two filters - one faced up and the other faced down. After the sampling, the water-soluble organic compounds was extracted by dissolution in ultra-pure water, sonication bath and filtration. The resulting filtered solutions were diluted in acidified water for the chromatographic separation. The results from liquid chromatography revealed the presence of the amino acids, although it was not possible to identify each one of them individually. The chromatograms and the fluorescence spectra showed the existence of some patterns: the samples that correspond to the up filters had more intense peaks and signals, revealing that the up filters collected more organic matter.
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Humans have a high ability to extract visual data information acquired by sight. Trought a learning process, which starts at birth and continues throughout life, image interpretation becomes almost instinctively. At a glance, one can easily describe a scene with reasonable precision, naming its main components. Usually, this is done by extracting low-level features such as edges, shapes and textures, and associanting them to high level meanings. In this way, a semantic description of the scene is done. An example of this, is the human capacity to recognize and describe other people physical and behavioral characteristics, or biometrics. Soft-biometrics also represents inherent characteristics of human body and behaviour, but do not allow unique person identification. Computer vision area aims to develop methods capable of performing visual interpretation with performance similar to humans. This thesis aims to propose computer vison methods which allows high level information extraction from images in the form of soft biometrics. This problem is approached in two ways, unsupervised and supervised learning methods. The first seeks to group images via an automatic feature extraction learning , using both convolution techniques, evolutionary computing and clustering. In this approach employed images contains faces and people. Second approach employs convolutional neural networks, which have the ability to operate on raw images, learning both feature extraction and classification processes. Here, images are classified according to gender and clothes, divided into upper and lower parts of human body. First approach, when tested with different image datasets obtained an accuracy of approximately 80% for faces and non-faces and 70% for people and non-person. The second tested using images and videos, obtained an accuracy of about 70% for gender, 80% to the upper clothes and 90% to lower clothes. The results of these case studies, show that proposed methods are promising, allowing the realization of automatic high level information image annotation. This opens possibilities for development of applications in diverse areas such as content-based image and video search and automatica video survaillance, reducing human effort in the task of manual annotation and monitoring.
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The faunal inventory of the macroinvertebrate community is important to the environmental assessment, since this biota is sensitive to human disturbance. The reservoir of Rio Verde, located on the first plateau of Paraná, is inserted into an agricultural region with several forest fragments Araucaria. The aim of this study was to evaluate the environmental integrity of the reservoir through ecological indexes of macroinvertebrate community benthic and associated with macrophytes. Five sampling points were defined in the study area, which comprise distinct microhabitats in the basin. There were four sampling campaigns, each by weather station: Spring (2014); Summer (2015); Autumn (2015) and Winter (2015). In each sample were measured abiotic various parameters in the field and be collected water samples for nutrient analysis in the laboratory. The macroinvertebrates were collected in triplicate at adapted Macan method using mesh sieve 1 mm and CPUE (catch per unit effort) for 20 minutes. In order to pellet sample was used a dredger model Petersen 2L. Still in the field, by season, samples were collected from macrophytes Myriophyllum aquaticum (Vell) Verdc. and Potamogeton montevidensis A. Benn. in triplicates in the fluvial region of the reservoir, to analyze the associated fractal dimension and macrofauna. For this we used a PVC sampler specific volume 0.025 m3. the following ecological descriptors were calculated in each case: abundance, wealth tax, wealth Margalef, Shannon-Wiener diversity, evenness evenness through the Past software. The index Biological Monitoring Working Party (BMWP) for monitoring sampling points was also calculated. Regarding the statistical analysis, we used the analysis of PERMANOVA to compare points and seasons and canonical correspondence analysis (CCoA) for variables. Regarding M. aquaticum and P. montevidensis it was not verified difference to the average associated macroinvertebrates. However there was a difference for abundance of organisms in the fractal dimension and biomass of specimens. M. aquaticum is more complex and took more macrofauna in relation to P. montevidensis. Regarding the monitoring of the reservoir, it showed up mesotrophic with moderate nutrient concentrations and within the regulatory limits. Benthic macrofauna showed statistical differences in relation to the reservoir region, sample point and temporal variation. The BMWP index showed that the river region has the highest biotic integrity (in all samples above 70 points), and the ecological descriptors of wealth and Margalef diversity of Shannon- Wiener higher. In point 4 (dam downstream) were recorded evidence of possible impacts due to lower wealth and BMWP index which resulted in a questionable quality water. New approaches are needed to focus on the aquatic community in the best understanding of this ecosystem and also with a view to environmental preservation of the Green River Basin.