988 resultados para ESTIMATIVA DE TEMPO


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Increased demand for energy and the search for alternative energy sources are remarkable and current facts. The management of domestic solid waste is also part of the issue in view of the possibility of power generation in existing landfills, which could provide financial autonomy to the system of waste management and improve the environmental balance of landfills in Brazil, currently only used for final solids disposal. Landfill gas is a viable alternative energy source has been tested in landfills in the World and in Brazil. Thus, the research aimed to evaluate the percentage of methane (CH4) present in three sinks of gases from a landfill in the municipality of Rio Claro – SP (Brazil), and to estimate the potential methane generation over its life through the application of a mathematical model. As a result it was found that in general the percentage of methane present in the gases is significant, between 50 and 62%. It was also noted that waste with disposal time between 8 and 12 months already are in the methanogenic stage. Finally, there was a tendency to increase the generation of methane in the transition periods of rain and drought

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The wide territorial extension of Brazil derails the installation and maintenance of instruments for measuring solar radiation, which makes necessary the development and application of models that are able to estimate reliable and sufficient data for many different activities that use such data. And these, in most cases, are estimated from the Ångström equation. Based on this model, this project aimed to estimate the global solar radiation at Presidente Prudente-SP, Brazil, using daily data from 1999 to 2007. The solar radiation data have been extracted from the paper tapes of actinograph bi-metallic (Robitsch) daily records at the meteorological station in the Faculty of Science and Technology, UNESP. These tapes were scanned, resulting in digital images with x and y coordinates pairs (x = time; y = solar radiation, cal/min.cm²). The daily global solar radiation is the area under the curve of the image. This value has been calculated by computer algorithms. After the acquisition and calculation of the values needed to develop the Ångström equation have been determined the constants a and b, using linear regression between the values of Rg/R0 (solar radiation/solar radiation on a horizontal surface at the top of atmosphere), as ordered, and n/N (number of hours of sunshine/day length in hours) as abscissa. The slope of the line will be the constant b and the linear coefficient, the constant a. The estimated results were compared to the observed using the Kolmogorov-Smirnov test, realizing that the models can be accepted. So, the equation to aim the solar global radiation is: Rg = R0 (0,2662+0,3592 n/N)

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Brazil faces a complex problem in respect to municipal solid waste, having been in recent years an increase of its generation without the country there be adequate for proper disposal thereof. In many states , the percentage of waste destined improperly , ie , in dumps , landfills, send- outs , among others , is greater than that disposed in landfills , which would be the most correct way to be made. It can be argued that this discrepancy is due to the high cost of implementation and operation of the landfill, and the same need large areas with physical characteristics that suit their operations . When there is a provision in properly constructed landfills , municipal solid waste grounded generate gases with high potential energy through biochemical reactions during the anaerobic decomposition of organic material stored . Such gases can be used for power generation within the landfill or other economic means . To estimate the gas generation will be sufficient for such economic compensation , there are mathematical models that make estimating the amount of gas produced . These models calculate the energy capacity and generation , using parameters obtained based on the characteristics of solid waste , climate of the region where they are grounded and grounding time . Such models have been raised and studied so that it was possible to perform simulations that demonstrate the behavior of biogas generation related to the external conditions of the landfill that interfere with biological reactions within. The results show differences between the values obtained , it shows that the preparation of the models found and used in the simulations were allocated amounts for different parameters that determine this difference in the estimate . Therefore, to rule, the models have difficulty understanding this because there is no clarity in the formulation of the equations , and the definition of variables and parameters would require a detailed study to...

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The study of mathematical modeling assists in evaluation of the capacity of production and measurement of generation time of biogas in landfills, enabling the implantation of projects of energy generation from methane. Thus, the work aims, by simulating scenarios of potential methane generation in the landfill in Rio Claro, the use of field data from methane flow and waste grounded parameters as references for selecting values of k e L0 used to estimate methane generation model in LandGEM. As a result it was found that compared the characteristics adopted in the four scenarios recommended by the USEPA literature with those found in the landfill of Rio Claro (high amount of organic matter in the waste landed and daily practice of leachate recirculation), the scenario that apparently better represent the rate of methane generation is the scenario 01, with k = 0.7 and L0 = 96. Now, the adjustment of parameters in relation to the data field of methane flow, the value of L0 which best fits the methane generation from the landfill in Rio Claro is 150, while for k the line behavior that best represents the reality are values between 0.7 and 0.3. Regarding the parameters of the waste grounded, between the suggested values of k, 0,3 is most consistent with the intermediate level of biological degradation of the residue grounded, while L0 due to the biodegradability of the waste, a new value between 120 and 150 may be more appropriate for the study

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OBJETIVO: Explorar quais medidas poderiam predizer a persistência de alterações específicas no desenvolvimento da linguagem (AEDL) a partir da associação entre os dados do desempenho na primeira avaliação fonoaudiológica e do prognóstico terapêutico da criança. MÉTODOS: Neste estudo retrospectivo, foram analisados 42 prontuários pertencentes a crianças com diagnóstico de AEDL. As idades variavam entre 21 e 63 meses no momento da primeira avaliação fonoaudiológica, que incluiu as provas de vocabulário, fonologia, pragmática e fluência. O desempenho dos sujeitos em cada prova foi pontuado de 0 a 4, com base na gravidade das alterações, sendo a pontuação máxima a adequada para a idade. Como medida prognóstica, contabilizamos o tempo de terapia (em sessões) dos pacientes que receberam alta, foram encaminhados (o quadro havia se tornado muito leve), ou permaneceram em terapia (dificuldades persistentes de linguagem). RESULTADOS: Houve associação entre os dados da avaliação inicial (classificação normal ou levemente alterada no vocabulário e pragmática) e o prognóstico (<135 sessões terapêuticas). A variável referente ao vocabulário foi a única capaz de predizer o tempo de terapia. A classificação como grave nesta medida aumentou, em média, 112 sessões na estimativa do tratamento. CONCLUSÃO: A primeira avaliação do vocabulário pode contribuir para predizer o prognóstico terapêutico da criança. Este achado é de relevância clínica e científica para a Fonoaudiologia, visto que oferece um recurso auxiliar para a realização do prognóstico e planejamento terapêutico nos quadros de AEDL.

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Desde o seu desenvolvimento na década de 1970 a tomografia computadorizada (TC) passou por grandes mudanças tecnológicas, tornando-se uma importante ferramenta diagnóstica para a medicina. Consequentemente o papel da TC em diagnóstico por imagem expandiu-se rapidamente, principalmente devido a melhorias na qualidade da imagem e tempo de aquisição. A dose de radiação recebida por pacientes devido a tais procedimentos vem ganhando atenção, levando a comunidade científica e os fabricantes a trabalharem juntos em direção a determinação e otimização de doses. Nas últimas décadas muitas metodologias para dosimetria em pacientes têm sido propostas, baseadas especialmente em cálculos utilizando a técnica Monte Carlo ou medições experimentais com objetos simuladores e dosímetros. A possibilidade de medições in vivo também está sendo investigada. Atualmente as principais técnicas para a otimização da dose incluem redução e/ou modulação da corrente anódica. O presente trabalho propõe uma metodologia experimental para estimativa de doses absorvidas pelos pulmões devido a protocolos clínicos de TC, usando um objeto simulador antropomórfico adulto e dosímetros termoluminescentes de Fluoreto de Lítio (LiF). Sete protocolos clínicos diferentes foram selecionados, com base em sua relevância com respeito à otimização de dose e frequência na rotina clínica de dois hospitais de grande porte: Instituto de Radiologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InRad) e Instituto do Câncer do Estado de São Paulo Octávio Frias de Oliveira (ICESP). Quatro protocolos de otimização de dose foram analisados: Auto mA, Auto + Smart mA, Baixa Dose (BD) e Ultra Baixa Dose (UBD). Os dois primeiros protocolos supracitados buscam redução de dose por meio de modulação da corrente anódica, enquanto os protocolos BD e UBD propõem a redução do valor da corrente anódica, mantendo-a constante. Os protocolos BD e UBD proporcionaram redução de dose de 72,7(8) % e 91(1) %, respectivamente; 16,8(1,3) % e 35,0(1,2) % de redução de dose foram obtidas com os protocolos Auto mA e Auto + Smart mA, respectivamente. As estimativas de dose para os protocolos analisados neste estudo são compatíveis com estudos similares publicados na literatura, demonstrando a eficiência da metodologia para o cálculo de doses absorvidas no pulmão. Sua aplicabilidade pode ser estendida a diferentes órgãos, diferentes protocolos de CT e diferentes tipos de objetos simuladores antropomórficos (pediátricos, por exemplo). Por fim, a comparação entre os valores de doses estimadas para os pulmões e valores de estimativas de doses dependentes do tamanho (Size Specific Dose Estimates SSDE) demonstrou dependência linear entre as duas grandezas. Resultados de estudos similares exibiram comportamentos similares para doses no reto, sugerindo que doses absorvidas pelos uma órgãos podem ser linearmente dependente dos valores de SSDE, com coeficientes lineares específicos para cada órgão. Uma investigação mais aprofundada sobre doses em órgãos é necessária para avaliar essa hipótese.

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A significant part of the life of a mechanical component occurs, the crack propagation stage in fatigue. Currently, it is had several mathematical models to describe the crack growth behavior. These models are classified into two categories in terms of stress range amplitude: constant and variable. In general, these propagation models are formulated as an initial value problem, and from this, the evolution curve of the crack is obtained by applying a numerical method. This dissertation presented the application of the methodology "Fast Bounds Crack" for the establishment of upper and lower bounds functions for model evolution of crack size. The performance of this methodology was evaluated by the relative deviation and computational times, in relation to approximate numerical solutions obtained by the Runge-Kutta method of 4th explicit order (RK4). Has been reached a maximum relative deviation of 5.92% and the computational time was, for examples solved, 130,000 times more higher than achieved by the method RK4. Was performed yet an Engineering application in order to obtain an approximate numerical solution, from the arithmetic mean of the upper and lower bounds obtained in the methodology applied in this work, when you don’t know the law of evolution. The maximum relative error found in this application was 2.08% which proves the efficiency of the methodology "Fast Bounds Crack".

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Dissertação (mestrado)—Universidade de Brasília, Faculdade UnB Gama, Faculdade de Tecnologia, Programa de Pós-graduação em Integridade de Materiais da Engenharia, 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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Radical-directed dissociation of gas phase ions is emerging as a powerful and complementary alternative to traditional tandem mass spectrometric techniques for biomolecular structural analysis. Previous studies have identified that coupling of 2-[(2,2,6,6-tetramethylpiperidin-1-oxyl)methyl] benzoic acid (TEMPO-Bz) to the N-terminus of a peptide introduces a labile oxygen-carbon bond that can be selectively activated upon collisional activation to produce a radical ion. Here we demonstrate that structurally-defined peptide radical ions can also be generated upon UV laser photodissociation of the same TEMPO-Bz derivatives in a linear ion-trap mass spectrometer. When subjected to further mass spectrometric analyses, the radical ions formed by a single laser pulse undergo identical dissociations as those formed by collisional activation of the same precursor ion, and can thus be used to derive molecular structure. Mapping the initial radical formation process as a function of photon energy by photodissociation action spectroscopy reveals that photoproduct formation is selective but occurs only in modest yield across the wavelength range (300-220 nm), with the photoproduct yield maximised between 235 and 225 nm. Based on the analysis of a set of model compounds, structural modifications to the TEMPO-Bz derivative are suggested to optimise radical photoproduct yield. Future development of such probes offers the advantage of increased sensitivity and selectivity for radical-directed dissociation. © 2014 the Owner Societies.

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Potenital pathways for the deactivation of hindered amine light stabilisers (HALS) have been investigated by observing reactions of model compounds-based on 4-substituted derivatives of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO)-with hydroxyl radicals. In these reactions, dilute aqueous suspensions of photocatalytic nanoparticulate titanium dioxide were irradiated with UV light in the presence of water-soluble TEMPO derivatives. Electron spin resonance (ESR) and electrospray ionisation mass-spectrometry (ESI-MS) data were acquired to provide complementary structural elucidation of the odd-and even-electron products of these reactions and both techniques show evidence for the formation of 4-oxo-TEMPO (TEMPONE). TEMPONE formation from the 4-substituted TEMPO compounds is proposed to be initiated by hydrogen abstraction at the 4-position by hydroxyl radical. High-level ab initio calculations reveal a thermodynamic preference for abstraction of this hydrogen but computed activation barriers indicate that, although viable, it is less favoured than hydrogen abstraction from elsewhere on the TEMPO scaffold. If a radical is formed at the 4-position however, calculations elucidate two reaction pathways leading to TEMPONE following combination with either a second hydroxyl radical or dioxygen. An alternate mechanism for conversion of TEMPOL to TEMPONE via an alkoxyl radical intermediate is also considered and found to be competitive with the other pathways. ESI-MS analysis also shows an increased abundance of analogous 4-substituted piperidines during the course of irradiation, suggesting competitive modification at the 1-position to produce a secondary amine. This modification is confirmed by characteristic fragmentation patterns of the ionised piperidines obtained by tandem mass spectrometry. The conclusions describe how reaction at the 4-position could be responsible for the gradual depletion of HALS in pigmented surface coatings and secondly, that modification at nitrogen to form the corresponding secondary amine species may play a greater role in the stabilisation mechanisms of HALS than previously considered.

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Many insect clades, especially within the Diptera (true flies), have been considered classically ‘Gondwanan’, with an inference that distributions derive from vicariance of the southern continents. Assessing the role that vicariance has played in the evolution of austral taxa requires testing the location and tempo of diversification and speciation against the well-established predictions of fragmentation of the ancient super-continent. Several early (anecdotal) hypotheses that current austral distributions originate from the breakup of Gondwana derive from studies of taxa within the family Chironomidae (non-biting midges). With the advent of molecular phylogenetics and biogeographic analytical software, these studies have been revisited and expanded to test such conclusions better. Here we studied the midge genus Stictocladius Edwards, from the subfamily Orthocladiinae, which contains austral-distributed clades that match vicariance-based expectations. We resolve several issues of systematic relationships among morphological species and reveal cryptic diversity within many taxa. Time-calibrated phylogenetic relationships among taxa accorded partially with the predicted tempo from geology. For these apparently vagile insects, vicariance-dated patterns persist for South America and Australia. However, as often found, divergence time estimates for New Zealand at c. 50 mya post-date separation of Zealandia from Antarctica and the remainder of Gondwana, but predate the proposed Oligocene ‘drowning’ of these islands. We detail other such ‘anomalous’ dates and suggest a single common explanation rather than stochastic processes. This could involve synchronous establishment following recovery from ‘drowning’ and/or deleteriously warming associated with the mid-Eocene climatic optimum (hence ‘waving’, which refers to cycles of drowning events) plus new availability of topography providing of cool running waters, or all these factors in combination. Alternatively a vicariance explanation remains available, given the uncertain duration of connectivity of Zealandia to Australia–Antarctic–South America via the Lord Howe and Norfolk ridges into the Eocene.

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Consultoria Legislativa - Área XVII - Segurança Pública e Defesa Nacional.