947 resultados para Uniaxial bianisotropic, Transverse transmission line method
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O objetivo deste trabalho é analisar o impacto dos Sistemas de Gestão Integrados (SGI) no desempenho organizacional sob a óptica do Triple Bottom Line (TBL), verificando se esta implementação auxilia a empresa a se tornar mais sustentável. A abordagem multi-método utilizada está dividida em três partes. A primeira compreende uma revisão sistemática da literatura, tendo como base a abordagem bibliométrica. A base de dados escolhida para a seleção dos artigos que compõem a amostra foi a ISI Web of Knowledge (Web of Science). As análises conduzidas sugerem lacunas na literatura a serem pesquisadas de modo a relacionar a integração dos sistemas de gestão como meio para as organizações tornarem-se mais sustentáveis, auxiliando assim na elaboração de um modelo teórico e das hipóteses de pesquisa. Os resultados parciais obtidos ressaltam a lacuna na literatura de estudos nessa área, principalmente que contemplem a dimensão social do Triple Bottom Line. Lacunas na literatura foram identificadas também no que se refere à análise do impacto da adoção dessas abordagens normativas no desempenho organizacional. A segunda etapa da metodologia é composta por estudos de casos múltiplos em empresas de diferentes setores e que tenham implantado sistemas de gestão de maneira integrada. Os resultados obtidos mostram que a certificação auxilia no desenvolvimento de ações sustentáveis, resultando em impactos econômicos, ambientais e sociais positivos. Nesta etapa, testou-se o modelo e as hipóteses levantadas na abordagem bibliométrica. A terceira etapa da metodologia é composta por análises estatísticas de dados secundários extraídos da revista Exame ?Maiores e Melhores\'. Os dados do ano de 2014 das empresas foram tratados por meio do software MINITAB 17 ®. Por meio do teste de mediana de mood, as amostras foram testadas e apresentaram diferenças estatisticamente significativas para o desempenho das empresas em diferentes setores. De maneira geral, as empresas com SGI apresentam melhor desempenho econômico do que as demais. Com a mesma base de dados, utilizando o modelo de equações estruturais e o software Smart PLS 2.0, criou-se um diagrama de caminhos analisando os constructos (SGI) com variáveis de desempenho (Endividamento, Lucratividade, Patrimônio, Crescimento e Retorno). O modelo de equações estruturais testado apresentou força para a relação entre SGI com Endividamento, Lucratividade, Patrimônio e Crescimento. As diferentes metodologias apresentadas contribuíram para responder a hipótese e afirmar com base na amostra deste trabalho que o SGI leva as empresas a terem melhor desempenho econômico, ambiental e social (baseado no TBL).
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The McCabe-Thiele method is a classical approximate graphical method for the conceptual design of binary distillation columns which is still widely used, mainly for didactical purposes, though it is also valuable for quick preliminary calculations. Nevertheless, no complete description of the method has been found and situations such as different thermal feed conditions, multiple feeds, possibilities to extract by-products or to add or remove heat, are not always considered. In the present work we provide a systematic analysis of such situations by developing the generalized equations for: a) the operating lines (OL) of each sector, and b) the changeover line that provides the connection between two consecutive trays of the corresponding sectors separated by a lateral stream of feed, product, or a heat removal or addition.
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Poster presented in the 11th Mediterranean Congress of Chemical Engineering, Barcelona, October 21-24, 2008.
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A microwave-based thermal nebulizer (MWTN) has been employed for the first time as on-line preconcentration device in inductively coupled plasma atomic emission spectrometry (ICP-AES). By the appropriate selection of the experimental conditions, the MWTN could be either operated as a conventional thermal nebulizer or as on-line analyte preconcentration and nebulization device. Thus, when operating at microwave power values above 100 W and highly concentrated alcohol solutions, the amount of energy per solvent mass liquid unit (EMR) is high enough to completely evaporate the solvent inside the system and, as a consequence, the analyte is deposited (and then preconcentrated) on the inner walls of the MWTN capillary. When reducing the EMR to the appropriate value (e.g., by reducing the microwave power at a constant sample uptake rate) the retained analyte is swept along by the liquid-gas stream and an analyte-enriched aerosol is generated and next introduced into the plasma cell. Emission signals obtained with the MWTN operating in preconcentration-nebulization mode improved when increasing preconcentration time and sample uptake rate as well as when decreasing the nozzle inner diameter. When running with pure ethanol solution at its optimum experimental conditions, the MWTN in preconcentration-nebulization mode afforded limits of detection up to one order of magnitude lowers than those obtained operating the MWTN exclusively as a nebulizer. To validate the method, the multi-element analysis (i.e. Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Pb and Zn) of different commercial spirit samples in ICP-AES has been performed. Analyte recoveries for all the elements studied ranged between 93% and 107% and the dynamic linear range covered up to 4 orders of magnitude (i.e. from 0.1 to 1000 μg L−1). In these analysis, both MWTN operating modes afforded similar results. Nevertheless, the preconcentration-nebulization mode permits to determine a higher number of analytes due to its higher detection capabilities.
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Power line interference is one of the main problems in surface electromyogram signals (EMG) analysis. In this work, a new method based on the stationary wavelet packet transform is proposed to estimate and remove this kind of noise from EMG data records. The performance has been quantitatively evaluated with synthetic noisy signals, obtaining good results independently from the signal to noise ratio (SNR). For the analyzed cases, the obtained results show that the correlation coefficient is around 0.99, the energy respecting to the pure EMG signal is 98–104%, the SNR is between 16.64 and 20.40 dB and the mean absolute error (MAE) is in the range of −69.02 and −65.31 dB. It has been also applied on 18 real EMG signals, evaluating the percentage of energy respecting to the noisy signals. The proposed method adjusts the reduction level to the amplitude of each harmonic present in the analyzed noisy signals (synthetic and real), reducing the harmonics with no alteration of the desired signal.
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We present a targetless motion tracking method for detecting planar movements with subpixel accuracy. This method is based on the computation and tracking of the intersection of two nonparallel straight-line segments in the image of a moving object in a scene. The method is simple and easy to implement because no complex structures have to be detected. It has been tested and validated using a lab experiment consisting of a vibrating object that was recorded with a high-speed camera working at 1000 fps. We managed to track displacements with an accuracy of hundredths of pixel or even of thousandths of pixel in the case of tracking harmonic vibrations. The method is widely applicable because it can be used for distance measuring amplitude and frequency of vibrations with a vision system.
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A novel polymer/TiC nanocomposites “PPA/TiC, poly(PA-co-ANI)/TiC and PANI/TiC” was successfully synthesized by chemical oxidation polymerization at room temperature using p-anisidine and/or aniline monomers and titanium carbide (TiC) in the presence of hydrochloric acid as a dopant with ammonium persulfate as oxidant. These nanocomposites obtained were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and thermogravimetric analysis (TGA). XRD indicated the presence of interactions between polymers and TiC nanoparticle and the TGA revealed that the TiC nanoparticles improve the thermal stability of the polymers. The electrical conductivity of nanocomposites is in the range of 0.079–0.91 S cm−1. The electrochemical behavior of the polymers extracted from the nanocomposites has been analyzed by cyclic voltammetry. Good electrochemical response has been observed for polymer films; the observed redox processes indicate that the polymerisation on TiC nanoparticles produces electroactive polymers. These nanocomposite microspheres can potentially used in commercial applications as fillers for antistatic and anticorrosion coatings.
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This layer is a digital raster graphic of the historic 15-minute USGS topographic quadrangle map of Barnstable, Massachusetts. The edition date is 1893 and the map was reprinted in 1907. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.
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This layer is a digital raster graphic of the historic 15-minute USGS topographic quadrangle map of Barre, Massachusetts. The suvery (ground condition) date is 1887, the edition date is March, 1894 and the map was reprinted in 1942. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.
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This layer is a digital raster graphic of the historic 15-minute USGS topographic quadrangle map of Becket, Massachusetts. The survey (ground condition) date is 1886. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.
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This layer is a digital raster graphic of the historic 15-minute USGS topographic map of the Belchertown, Massachusetts quadrangle. The suvey (ground condition) dates are 1885 and 1887; the edition date is November, 1893. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.
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This layer is a digital raster graphic of the historic 15-minute USGS topographic quadrangle map entitled Berlin, (N.Y.) which also shows towns and features in Massachusetts. The survey dates (ground condition) for this map are 1885-88, and the edition date is 1890. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.
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This layer is a digital raster graphic of the historic 15-minute USGS topographic map of the Blackstone, Massachusetts quadrangle. The survey date (ground condition) of this map is 1886 and the edition date is October, 1893. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.
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This layer is a digital raster graphic (DRG) of the historic 15-minute USGS topographic map of the Boston, Massachusetts quadrangle. The survey date (ground condition) of this map ranges from 1898 to 1900, the edition date is July, 1903 and it was reprinted in 1918. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.
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This layer is a digital raster graphic (DRG) of the historic 15-minute USGS topographic map of the Boston North, Massachusetts quadrangle. The survey date (ground condition) of this map is 1943, the edition date is 1946. A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is geo-referenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The names of quadrangles which border this one appear on the map collar in their respective positions (N,S,E,W) in relation to this map.