892 resultados para Manufatura em massa atual
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Este trabalho apresenta uma abordagem teórica no que tange a erosão de margens (erosion of margins) e movimentos de massa (mass movement) na calha do rio Solimões (AM). Constitui resultados conduzidos por meio da análise comparativa de trabalhos realizados em ambientes fluviais. A metodologia consistiu de levantamentos de campo onde foram identificados e classificados os processos de erosão de margem e os tipos de movimentos massa, que resultam em impactos socioambientais sobre os moradores da paisagem de várzea na Amazônia. A realização da pesquisa foi trabalhada por meio das seguintes etapas: revisão bibliográfica, observação e mensuração direta no campo com análise descritiva dos processos, ao longo da costa da comunidade do Divino Espírito Santo. Para as mensurações e cadastros dos pontos de erosão utilizou-se trena, GPS, caderneta e fotografias digital (10.0 meg.pixels) obtidas na lateral dos barrancos para a visualização e identificação das formas e cicatrizes de movimentos de massa, nas zonas de perigo e riscos aos moradores. Os resultados citados neste trabalho vêm contribuir para o entendimento da complexa dinâmica fluvial, em especial os processos de erosão de margens e movimentos de massa que ocorrem com bastante intensidade ao longo da costa da comunidade do Divino Espírito Santo.
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A geomorfologia é o ramo da geografia que estuda as formas de relevo atuantes na superfície terrestre. Baseada nos conceitos geomorfológicos, geológicos e geográficos este estudo tem por fundamento a análise dos movimentos de massa e dos processos geomorfológicos (escorregamentos de detritos, sulcos, ravinas) ocorrentes no morro do capóia, localizado na rodovia MT 170, que liga o município de Juína a Castanheira. Esta região se localiza na Mesorregião Norte e Microrregião de Aripuanã na Depressão do Norte de Mato Grosso, no estado de Mato Grosso, região onde se pode diagnosticar relevo bastante acidentado, e que no período de 2008 a 2010 foi realizada a pavimentação asfáltica da rodovia, considerando assim os acidentes geológicos e geomorfológicos encontrados, como conseqüência do uso excessivo de maquinas pesadas e a interferência humana no ciclo natural, observada no aterro realizado no morro e em vários outros pontos da via, além da mudança no curso do Rio das Pedras para a construção da ponte. Durante esta pesquisa foi possível aprofundar acerca da geomorfologia regional e também identificar os riscos de desmoronamentos das encostas bem como outras vertentes que possam interferir diretamente no uso da rodovia pelos seus transeuntes. Para o melhor aprofundamento dos estudos físicos da área foram utilizados estudos topográficos e imagens de satélite, além de acervo fotográfico, que possibilitaram a análise da dinâmica geomorfológica. Para tanto se fez necessário pesquisa bibliográficas sobre geografia física, geomorfologia e geologia, além das pesquisas in loco, onde se pode ver a dimensão das erosões e a composição geomorfológica da área. Utilizou-se também do mapa topográfico da rodovia construído pelos profissionais da Constil (empresa responsável pela construção do asfalto). Pode-se dizer, então, que a rodovia passa por um momento de degradação, ou seja, os movimentos de massa vêm acontecendo gradativamente comprometendo a estrutura mesma.
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As pastagens naturais do Rio Grande do Sul tem sido consideradas como importante base forrageira para a produção animal em sistemas de produção de base familiar.
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Os biofertilizantes, resultantes da fermentação de estercos ou de material vegetal, são insumos alternativos. Por outro lado, o coentro é uma hortaliça folhosa condimentar de grande expressão socioeconômica no norte e nordeste do Brasil. Objetivou-se testar diferentes biofertilizantes em coentro, cv. Verdão, em casa de vegetação, na Embrapa Amazônia Ocidental (Iranduba-AM), de 12/11/13 a 28/11/13.
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2016
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Faz vários anos que se sabe como os blogueiros e outros comentaristas on-line independentes criticam, corrigem, e de outra maneira desafiam o jornalismo convencional, porém isto ainda não foi plenamente aceito pelos jornalistas; as hostilidades entre as empresas de mídia e a nova geração de jornalistas cidadãos continuam a irromper de vez em quando. O antigo monopólio de gatekeeping mantido pela mídia de massa tem sido desafiado pela nova prática de gatewatching: feita pelos blogueiros individuais e pelas comunidades de comentaristas que podem não fazer reportagem das notícias de primeira mão, porém fazem a curation e avaliam as notícias e outras informações fornecidas pelas fontes oficiais, e assim prestam um serviço importante. E isto ocorre atualmente com cada vez mais rapidez, quase em tempo real: usando as redes sociais mais recentes, que divulgam, compartilham, comentam, questionam e desacreditam as matérias noticiosas dentro de minutos, e usando plataformas adicionais que possibilitam a colaboração ad hoc rápida e eficaz entre os usuários. Quando centenas de voluntários podem provar dentro de alguns poucos dias que um ministro alemão foi culpado de plágio sério, quando o mundo inteiro fica sabendo de terremotos e tsunamis pelo Twitter – como é que o jornalismo consegue acompanhar tudo isto?
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In our laboratory we have developed a quantitative-polymerase chain reaction (Q-PCR) strategy to examine the differential expression of adenosine receptor (ADOR), A(1), A(2A), A(2B) and A(3), and estrogen receptors (ER) alpha and beta. Brain and uterine mRNA were first used to optimise specific amplification conditions prior to SYBR Green I real time analysis of receptor subtype expression. SYBR Green I provided a convenient and sensitive means of examining specific PCR amplification product in real time, and allowed the generation of standard curves from which relative receptor abundance could be determined. Real time Q-PCR analysis was then performed, to examine changes in receptor expression levels in brains of adult female Wistar rats 3-month post ovariectomy. Comparison with sham-operated age-matched control rats demonstrated both comparative and absolute-copy number changes in receptor levels. Evaluation of both analytical methods investigated 18S rRNA as an internal reference for comparative gene expression analysis in the brain. The results of this study revealed preferential repression of ADORA(2A) (>4-fold down) and consistent (>2-fold) down-regulation of ADORA(1), ADORA(3), and ER-beta, following ovariectomy. No change was found in ADORA(2B) or ER-alpha. Analysis of absolute copy number in this study revealed a correlation between receptor expression in response to ovariectomy, and relative receptor subtype abundance in the brain.
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Constant changes in the global economic environment require companies to revisit traditional assumptions about how businesses create and capture value (Teece, 2010). In recent years, management practice literature has focused largely on better understanding business models and business model innovation (Amit, Zott and Massa, 2010; Johnson, Christensen and Kagermann, 2008). Much has been written on the benefits of linking design and design thinking to organisational strategies and business transformation. However, very little has been researched and reported on regarding the impact of design led approaches to triple bottom-line opportunities such as, social innovation enterprise. In the context of this paper Design Led Innovation is defined as the tools and approaches which enable design thinking to be embedded as an element of cultural transformation within a business. Being Design Led requires a company to have a vision for top line growth founded on deep customer insights and expanded through customer and stakeholder engagements. The outcomes of this are then mapped to all aspects of the business, enabling the vision to be successfully implemented and achieved. It is the latter part of this definition where we believe Design Led Innovation has the greatest value in transforming social innovation enterprise into a sustainable business venture. However, we also acknowledge that enabling these firms to think strategically about their business model is difficult given the unique operational and funding challenges that often characterize many social enterprises. The purpose of this paper, therefore, is to pose the question, do sustainable innovation enterprise innovate their business model? And if so, how? It is the authors’ opinion that such enterprises only innovate at the product or system level without a complete understanding of the business model structure, which underpins the long term viability. However, in this paper we challenge this notion and explore if such firms can overcome their size and operational constraints to become sustainable enterprises using a design led approach. This is achieved through contextualizing business model innovation, briefly defining social innovation enterprise and profiling a new and emerging industry in Australia – Clean Technology. Future research challenges and opportunities are also presented.
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In technicolor theories the scalar sector of the Standard Model is replaced by a strongly interacting sector. Although the Standard Model has been exceptionally successful, the scalar sector causes theoretical problems that make these theories seem an attractive alternative. I begin my thesis by considering QCD, which is the known example of strong interactions. The theory exhibits two phenomena: confinement and chiral symmetry breaking. I find the low-energy dynamics to be similar to that of the sigma models. Then I analyze the problems of the Standard Model Higgs sector, mainly the unnaturalness and triviality. Motivated by the example of QCD, I introduce the minimal technicolor model to resolve these problems. I demonstrate the minimal model to be free of anomalies and then deduce the main elements of its low-energy particle spectrum. I find the particle spectrum contains massless or very light technipions, and also technibaryons and techni-vector mesons with a high mass of over 1 TeV. Standard Model fermions remain strictly massless at this stage. Thus I introduce the technicolor companion theory of flavor, called extended technicolor. I show that the Standard Model fermions and technihadrons receive masses, but that they remain too light. I also discuss flavor-changing neutral currents and precision electroweak measurements. I then show that walking technicolor models partly solve these problems. In these models, contrary to QCD, the coupling evolves slowly over a large energy scale. This behavior adds to the masses so that even the light technihadrons are too heavy to be detected at current particle accelerators. Also all observed masses of the Standard Model particles can be generated, except for the bottom and top quarks. Thus it is shown in this thesis that, excluding the masses of third generation quarks, theories based on walking technicolor can in principle produce the observed particle spectrum.
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It has been known for decades that particles can cause adverse health effects as they are deposited within the respiratory system. Atmospheric aerosol particles influence climate by scattering solar radiation but aerosol particles act also as the nuclei around which cloud droplets form. The principal objectives of this thesis were to investigate the chemical composition and the sources of fine particles in different environments (traffic, urban background, remote) as well as during some specific air pollution situations. Quantifying the climate and health effects of atmospheric aerosols is not possible without detailed information of the aerosol chemical composition. Aerosol measurements were carried out at nine sites in six countries (Finland, Germany, Czech, Netherlands, Greece and Italy). Several different instruments were used in order to measure both the particulate matter (PM) mass and its chemical composition. In the off-line measurements the samples were collected first on a substrate or filter and gravimetric and chemical analysis were conducted in the laboratory. In the on-line measurements the sampling and analysis were either a combined procedure or performed successively within the same instrument. Results from the impactor samples were analyzed by the statistical methods. This thesis comprises also a work where a method for the determination carbonaceous matter size distribution by using a multistage impactor was developed. It was found that the chemistry of PM has usually strong spatial, temporal and size-dependent variability. In the Finnish sites most of the fine PM consisted of organic matter. However, in Greece sulfate dominated the fine PM and in Italy nitrate made the largest contribution to the fine PM. Regarding the size-dependent chemical composition, organic components were likely to be enriched in smaller particles than inorganic ions. Data analysis showed that organic carbon (OC) had four major sources in Helsinki. Secondary production was the major source in Helsinki during spring, summer and fall, whereas in winter biomass combustion dominated OC. The significant impact of biomass combustion on OC concentrations was also observed in the measurements performed in Central Europe. In this thesis aerosol samples were collected mainly by the conventional filter and impactor methods which suffered from the long integration time. However, by filter and impactor measurements chemical mass closure was achieved accurately, and a simple filter sampling was found to be useful in order to explain the sources of PM on the seasonal basis. The online instruments gave additional information related to the temporal variations of the sources and the atmospheric mixing conditions.
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Recent epidemiological studies have shown a consistent association of the mass concentration of urban air thoracic (PM10) and fine (PM2.5) particles with mortality and morbidity among cardiorespiratory patients. However, the chemical characteristics of different particulate size ranges and the biological mechanisms responsible for these adverse health effects are not well known. The principal aims of this thesis were to validate a high volume cascade impactor (HVCI) for the collection of particulate matter for physicochemical and toxicological studies, and to make an in-depth chemical and source characterisation of samples collected during different pollution situations. The particulate samples were collected with the HVCI, virtual impactors and a Berner low pressure impactor in six European cities: Helsinki, Duisburg, Prague, Amsterdam, Barcelona and Athens. The samples were analysed for particle mass, common ions, total and water-soluble elements as well as elemental and organic carbon. Laboratory calibration and field comparisons indicated that the HVCI can provide a unique large capacity, high efficiency sampling of size-segregated aerosol particles. The cutoff sizes of the recommended HVCI configuration were 2.4, 0.9 and 0.2 μm. The HVCI mass concentrations were in a good agreement with the reference methods, but the chemical composition of especially the fine particulate samples showed some differences. This implies that the chemical characterization of the exposure variable in toxicological studies needs to be done from the same HVCI samples as used in cell and animal studies. The data from parallel, low volume reference samplers provide valuable additional information for chemical mass closure and source assessment. The major components of PM2.5 in the virtual impactor samples were carbonaceous compounds, secondary inorganic ions and sea salt, whereas those of coarse particles (PM2.5-10) were soil-derived compounds, carbonaceous compounds, sea salt and nitrate. The major and minor components together accounted for 77-106% and 77-96% of the gravimetrically-measured masses of fine and coarse particles, respectively. Relatively large differences between sampling campaigns were observed in the organic carbon content of the PM2.5 samples as well as the mineral composition of the PM2.5-10 samples. A source assessment based on chemical tracers suggested clear differences in the dominant sources (e.g. traffic, residential heating with solid fuels, metal industry plants, regional or long-range transport) between the sampling campaigns. In summary, the field campaigns exhibited different profiles with regard to particulate sources, size distribution and chemical composition, thus, providing a highly useful setup for toxicological studies on the size-segregated HVCI samples.
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By detecting leading protons produced in the Central Exclusive Diffractive process, p+p → p+X+p, one can measure the missing mass, and scan for possible new particle states such as the Higgs boson. This process augments - in a model independent way - the standard methods for new particle searches at the Large Hadron Collider (LHC) and will allow detailed analyses of the produced central system, such as the spin-parity properties of the Higgs boson. The exclusive central diffractive process makes possible precision studies of gluons at the LHC and complements the physics scenarios foreseen at the next e+e− linear collider. This thesis first presents the conclusions of the first systematic analysis of the expected precision measurement of the leading proton momentum and the accuracy of the reconstructed missing mass. In this initial analysis, the scattered protons are tracked along the LHC beam line and the uncertainties expected in beam transport and detection of the scattered leading protons are accounted for. The main focus of the thesis is in developing the necessary radiation hard precision detector technology for coping with the extremely demanding experimental environment of the LHC. This will be achieved by using a 3D silicon detector design, which in addition to the radiation hardness of up to 5×10^15 neutrons/cm2, offers properties such as a high signal-to- noise ratio, fast signal response to radiation and sensitivity close to the very edge of the detector. This work reports on the development of a novel semi-3D detector design that simplifies the 3D fabrication process, but conserves the necessary properties of the 3D detector design required in the LHC and in other imaging applications.
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The Transition Radiation Tracker (TRT) of the ATLAS experiment at the LHC is part of the Inner Detector. It is designed as a robust and powerful gaseous detector that provides tracking through individual drift-tubes (straws) as well as particle identification via transition radiation (TR) detection. The straw tubes are operated with Xe-CO2-O2 70/27/3, a gas that combines the advantages of efficient TR absorption, a short electron drift time and minimum ageing effects. The modules of the barrel part of the TRT were built in the United States while the end-cap wheels are assembled at two Russian institutes. Acceptance tests of barrel modules and end-cap wheels are performed at CERN before assembly and integration with the Semiconductor Tracker (SCT) and the Pixel Detector. This thesis first describes simulations the TRT straw tube. The argon-based acceptance gas mixture as well as two xenon-based operating gases are examined for its properties. Drift velocities and Townsend coefficients are computed with the help of the program Magboltz and used to study electron drift and multiplication in the straw using the software Garfield. The inclusion of Penning transfers in the avalanche process leads to remarkable agreements with experimental data. A high level of cleanliness in the TRT s acceptance test gas system is indispensable. To monitor gas purity, a small straw tube detector has been constructed and extensively used to study the ageing behaviour of the straw tube in Ar-CO2. A variety of ageing tests are presented and discussed. Acceptance tests for the TRT survey dimensions, wire tension, gas-tightness, high-voltage stability and gas gain uniformity along each individual straw. The thesis gives details on acceptance criteria and measurement methods in the case of the end-cap wheels. Special focus is put on wire tension and straw straightness. The effect of geometrically deformed straws on gas gain and energy resolution is examined in an experimental setup and compared to simulation studies. An overview of the most important results from the end-cap wheels tested up to this point is presented.
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While there is evidence that science and non-science background students display small differences in performance in basic and clinical sciences, early in a 4-year, graduate entry medical program, this lessens with time. With respect to anatomy knowledge, there are no comparable data as to the impact previous anatomy experience has on the student perception of the anatomy practical learning environment. A study survey was designed to evaluate student perception of the anatomy practical program and its impact on student learning, for the initial cohort of a new medical school. The survey comprised 19 statements requiring a response using a 5-point Likert scale, in addition to a free text opportunity to provide opinion of the perceived educational value of the anatomy practical program. The response rate for a total cohort of 82 students was 89%. The anatomy practical program was highly valued by the students in aiding their learning of anatomy, as indicated by the high mean scores for all statements (range: 4.04-4.7). There was a significant difference between the students who had and had not studied a science course prior to entering medicine, with respect to statements that addressed aspects of the course related to its structure, organization, variety of resources, linkage to problem-based learning cases, and fairness of assessment. Nonscience students were more positive compared to those who had studied science before (P levels ranging from 0.004 to 0.035). Students less experienced in anatomy were more challenged in prioritizing core curricular knowledge. © 2011 Wiley-Liss, Inc.
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Inflation is a period of accelerated expansion in the very early universe, which has the appealing aspect that it can create primordial perturbations via quantum fluctuations. These primordial perturbations have been observed in the cosmic microwave background, and these perturbations also function as the seeds of all large-scale structure in the universe. Curvaton models are simple modifications of the standard inflationary paradigm, where inflation is driven by the energy density of the inflaton, but another field, the curvaton, is responsible for producing the primordial perturbations. The curvaton decays after inflation as ended, where the isocurvature perturbations of the curvaton are converted into adiabatic perturbations. Since the curvaton must decay, it must have some interactions. Additionally realistic curvaton models typically have some self-interactions. In this work we consider self-interacting curvaton models, where the self-interaction is a monomial in the potential, suppressed by the Planck scale, and thus the self-interaction is very weak. Nevertheless, since the self-interaction makes the equations of motion non-linear, it can modify the behaviour of the model very drastically. The most intriguing aspect of this behaviour is that the final properties of the perturbations become highly dependent on the initial values. Departures of Gaussian distribution are important observables of the primordial perturbations. Due to the non-linearity of the self-interacting curvaton model and its sensitivity to initial conditions, it can produce significant non-Gaussianity of the primordial perturbations. In this work we investigate the non-Gaussianity produced by the self-interacting curvaton, and demonstrate that the non-Gaussianity parameters do not obey the analytically derived approximate relations often cited in the literature. Furthermore we also consider a self-interacting curvaton with a mass in the TeV-scale. Motivated by realistic particle physics models such as the Minimally Supersymmetric Standard Model, we demonstrate that a curvaton model within the mass range can be responsible for the observed perturbations if it can decay late enough.