952 resultados para Euclidean sphere
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Esta tese versa sobre a análise de um dos grandes projetos tecnológicos do Estado nacional, o PEB, com o intuito de verificar em que medida o Brasil, enquanto País em desenvolvimento e inserido no processo de globalização econômica, tem a possibilidade de autodeterminar um projeto nacional de desenvolvimento relativamente soberano e sustentável, mediante sua capacitação tecnológica em áreas de ponta, como as tecnologias espaciais. Neste ínterim, é discutido o processo de institucionalização da ciência no País e a implantação de um moderno sistema de C&T no Brasil através de uma aliança entre cientistas e militares, culminando com a criação do CNPq em 1951. Apresentamos uma releitura da nossa recente história política e os projetos nacionais de desenvolvimento de que foi alvo o País, formulados pelos grupos sociais mais representativos da sociedade na época estudada, recuperando uma discussão que, estendendo-se por décadas, reservou à questão científica um lugar privilegiado no planejamento do Estado. O período da ditadura militar é especialmente contemplado, considerando-se ter sido esta a fase em que realmente o Programa Espacial Brasileiro sofreu maiores investimentos, conferindo aos militares um papel de destaque no quadro de atores sociais coletivos empenhados no projeto de desenvolvimento do País, destacando as diversas correntes ideológicas em ação dentro das Forças Armadas. Foi analisado o processo de globalização devido ao seu nexo interno e externo com as políticas científicas implantadas ou preconizadas no País. Esse processo, alavancado pela nova dinâmica tecnológica internacional iniciada nos anos 1980, estabeleceu profundos impactos e mudanças na constituição atual da esfera do político. Este é o cenário onde, de nosso ponto de vista, inscreve-se a questão da capacitação científico-tecnológica como variável estratégica em todos os níveis das relações internacionais. A compreensão desta problemática deve ser entendida como parte do cenário mundial que se configurou nas últimas décadas do século XX, tendo no entrelaçamento das dinâmicas científico-tecnológica e a soberania nacional dos Estados uma sinergia diferenciada na reordenação geopolítica contemporânea.
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A motivação para estudar modelos de democracia, em especial a participativa no viés deliberativo, deita raízes na conjuntura histórica compreendendo pelo menos duas décadas, em que ocorrem debates acadêmicos, lutas democráticas e movimentos sociais que vêm em alguns países nos últimos anos dando voz às reivindicações populares por mudanças nos modelos atuais de democracia, e por maior participação popular e um alargamento dos espaços públicos para discussões. Nesse contexto, o Orçamento Participativo se destaca como experiência no Brasil e em muitos países como instrumento para essas mudanças. O marco teórico escolhido foi a démarche de Jürgen Habermas. Suas digressões sobre democracia deliberativa envolvem diretamente as formulações sobre o conteúdo da esfera pública e seu reposicionamento em arranjo interno mais amplo relacionando-a com os sistemas da sociedade. A principal experiência objeto da pesquisa foi o Orçamento Participativo de Cascais, em razão do estágio de doutoramento com bolsa concedida pela CAPES no ano de 2013.
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Esta Tese examina as implicações políticas da cooperação internacional para o desenvolvimento de Moçambique em três momentos: (i) o período referente à solidariedade socialista; (ii) o contexto da cooperação tradicional Norte-Sul; (iii) a experiência (re) emergente da Cooperação Sul-Sul. Nossa incursão analítica mostra que foram cerca de 40 anos de cooperação internacional que permitiram uma série de transformações em nível político, econômico e social, e que construíram um país como um autêntico artefato de intervenção externa. Nesse sentido, analisam-se os efeitos políticos provocados pelas três propostas sugeridas de cooperação na esfera doméstica de Moçambique. Por um lado, constata-se que a cooperação internacional acaba por constituir-se em projeto de poder que afeta a produção de políticas públicas, a construção da autonomia e, mais recentemente, o processo de democratização em curso. Por outro, evidencia-se que os atores internacionais que atuam no campo da cooperação para o desenvolvimento em Moçambique agem imbuídos de seus respectivos interesses e agendas de política externa. Na relação entre os distintos atores e o Estado moçambicano, identificam-se alguns fatores-chave, tais como a fraca capacidade estatal, a existência de enormes assimetrias entre Moçambique e seus parceiros, o vício em receber cooperação que transforma essa relação em uma das principais fontes de manutenção do Estado, bem como a preservação das elites políticas tradicionais fatores que limitam o alcance dos objetivos reais de desenvolvimento que as distintas formas e modalidades de cooperação internacional prometem e buscam promover.
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A dissertação apresenta um estudo sobre a constituição do Fundo Público no capitalismo contemporâneo, a partir das três grandes crises do capital do século XX. Realizaremos, para tanto, uma incursão histórica e analítica, percorrendo o início do século XX até os dias atuais, demonstrando a importância e imprescindibilidade do Fundo Público para a reprodução do capital e do trabalhador. Neste contexto, de expansão e retração da economia em nível mundial, analisaremos os rebatimentos no Brasil, a partir da contrarreforma do Estado, na apropriação e composição do fundo público brasileiro. Ao garantir a reprodução do trabalhador, o Fundo Público o faz por meio das políticas sociais, e em especial, trabalharemos a Política de Assistência Social. O objetivo deste trabalho é realizar análise sobre todos os recursos destinados ao Fundo Municipal de Assistência Social do município de Campos dos Goytacazes, que servirão para o financiamento da rede socioassistencial em âmbito municipal no período de 2004 a 2012. Analisaremos, portanto, os recursos municipal, estadual e federal, tendo como base os segintes documentos: Demonstrativo da Evolução Orçamentária e de Despesas, Relatório de Receitas Geral, Lei de Diretrizes Orçamentária e a lei Orçamentária Anual, que serão transferidos para o fundo e de que forma o poder executivo prioriza a gestão destes recursos, por meio de suas despesas. O resultado da pesquisa nos mostrou que a Política de Assistência Social é cofinanciada pelos três entes federativos, no entanto, evidenciamos grandes dificuldades para a gestão compartilhada. O município é o maior financiador desta política, entremente, seus recursos são alocados prioritariamente nos Programas de Transferência de Renda municipais e nas entidades filantrópicas, enquanto os programas federais ficam sob a responsabilidade majoritária da União. O estado neste processo, quase que esquecido, se mostra com um financiamento extremamente pontual, descontínuo e ínfimo. Dos recursos direcionados a esta política, identificamos um grande montante que não são executados, o que consideramos hoje um dos grandes desafios para a efetivação desta Política em Campos dos Goytacazes.
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A presente dissertação investiga o jornalismo exercido pela TV Alerj (Assembleia Legislativa do Estado do Rio de Janeiro), estabelecendo como objeto específico a análise do Jornal da Alerj, principal telejornal da emissora. A partir do método do modo de endereçamento de telejornais exibidos 2013, seus resultados nos permitem afirmar que as edições recorrem a uma série de recursos e formatos de construção da imagem do Parlamento como instituição que presta contas ao cidadão, oferece transparência em seus atos e procura dar significatividade a assuntos que geralmente estão à margem do conhecimento público. Por outro lado, a mesma metodologia possibilitou identificar estratégias que contribuem para o silenciamento de discursos e gestos políticos e práticas que reforçam o centralismo de atores políticos, distanciando-se da missão de um veículo estatal com papel público de informar e com uma alta carga de institucionalidade. Para aferir os resultados, adotamos como percurso teórico o princípio da publicidade de Kant e dialogamos o conceito com a esfera pública habermasiana, sob a perspectiva de ser mais do que uma arena de debates, mas um referencial de visibilidade e discussão públicas. Desse modelo, resultam propostas em torno da Comunicação Pública em diferentes realidades (França, Itália, Reino Unido, Colômbia e Brasil) e a aplicação nas emissoras legislativas
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Os métodos de otimização que adotam condições de otimalidade de primeira e/ou segunda ordem são eficientes e normalmente esses métodos iterativos são desenvolvidos e analisados através da análise matemática do espaço euclidiano n-dimensional, o qual tem caráter local. Esses métodos levam a algoritmos iterativos que são usados para o cálculo de minimizadores globais de uma função não linear, principalmente não-convexas e multimodais, dependendo da posição dos pontos de partida. Método de Otimização Global Topográfico é um algoritmo de agrupamento, o qual é fundamentado nos conceitos elementares da teoria dos grafos, com a finalidade de gerar bons pontos de partida para os métodos de busca local, com base nos pontos distribuídos de modo uniforme no interior da região viável. Este trabalho tem como objetivo a aplicação do método de Otimização Global Topográfica junto com um método robusto e eficaz de direções viáveis por pontos-interiores a problemas de otimização que tem restrições de igualdade e/ou desigualdade lineares e/ou não lineares, que constituem conjuntos viáveis com interiores não vazios. Para cada um destes problemas, é representado também um hiper-retângulo compreendendo cada conjunto viável, onde os pontos amostrais são gerados.
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We have developed a novel human facial tracking system that operates in real time at a video frame rate without needing any special hardware. The approach is based on the use of Lie algebra, and uses three-dimensional feature points on the targeted human face. It is assumed that the roughly estimated facial model (relative coordinates of the three-dimensional feature points) is known. First, the initial feature positions of the face are determined using a model fitting technique. Then, the tracking is operated by the following sequence: (1) capture the new video frame and render feature points to the image plane; (2) search for new positions of the feature points on the image plane; (3) get the Euclidean matrix from the moving vector and the three-dimensional information for the points; and (4) rotate and translate the feature points by using the Euclidean matrix, and render the new points on the image plane. The key algorithm of this tracker is to estimate the Euclidean matrix by using a least square technique based on Lie algebra. The resulting tracker performed very well on the task of tracking a human face.
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Fishing in Sri Lanka has been carried on largely with the use of traditional methods and in recent years there has been a marked increase in the use of mechanized craft for fishing. Although some effort has been made in the sphere of deep-sea fishing both by trawlers and long line tuna boats, such efforts have not made a significant contribution towards improving the industry. The progress of deep-sea fishing in Sri Lanka has been hindered due to a number of reasons described by the author.
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Spined loach, Cobitis taenia, is a predominant fish in the river systems of the southern Caspian Sea basin. Although there is evidence of the geographical divergence of this taxon, but no information is available on morphological differences within the species populations. This study was designed to evaluate some biological factors including; morphometric and meristic characters, length-weight, age-growth, condition factor, diet, reproduction, variation and differentiation, in the Babolrud, Talar and Siahrud Rivers in south of the Caspian Sea basin. Age, sex ratio, fecundity, ova diameter and gonadosomatic index were estimated. Also, regression analyses was tested the relation between fecundity and fish length, weight, gonad weight, and also age. Totally 858 fish of which 721 were matures, were collected from these rivers by electrofishing. 37 morphometric characters, 9 meristic characters and 78 truss network system characters were estimated. Resulats of DFA analysis based on data of morphometric and meristic showd that these populations are highly (94.5%) varios from each other. In discriminate function analysis, the proportion of individuals correctly classified into their original groups was 61%, 65.4% and 86.5% for upstream and downstream, respectively. Clustering based on Euclidean distances among groups of centroids using an UPGMA and also principal component analysis’ results for morphometric data indicated that these populations from these three rivers were clearly distinct from each other. Regression equations between length and weight in these three populations were significantly different from Folton factor (b=3), that showed the fish has a negative Alometric growth process. Condition factor was estimated between 0.8912 to 1.2736 and 0.8131 to 1.4489 for males and females, respectively. Sex ratio (female: male) in these populations was 1.2816:1. The difference between the number of females and males was significant and females were more than males. The female and male specimens reach maturity by Tl more than 40 and 30 mm and at the age of 2+ and 1+, respectively. The mean of ova diameter was 0.5824±0.2882. The spawning took place from May to late July, at the water temperature from 18.7 to 24.0°C. The GSI values average at the beginning of the reproduction period was about 9%, with ranged from 2 to 26% in ripe mature females. The absolute and relative fecundity were 2109±792 and 579±208 respectively. The absolute fecundity was significantly related to body weight and gonads weight. Based on the pattern of gonado-somatic index, it was concluded that this fish has prolong active reproductive period, which is a type of adaptation by short-lived small fishes to environmental conditions. The macroscopic and histological results showed that the female and male have 5 and 4 stages in their maturation process, respectively. The RLG index was about 0.4732, which showed the fish is a carnivorous species. Significant difference was observed between fishes with different length and diet. The main foods of the fish were Trichoptera, Chironomidae larvae and Ephemeroptera which were their prefered food as well, however it was estimated that the food selection and diet are affected by environmental conditions.
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One of the most endangered populations of Black-necked Cranes (Grus nigricollis), the central population, is declining due to habitat loss and degradation, but little is known about their space use patterns and habitat preferences. We examined the space use and habitat preferences of Black-necked Cranes during the winter of 2007-2008 at the Napahai wetland in northwest Yunnan, China, where approximately 300 Black-necked Cranes (>90% of the total central population) spent the winter. Euclidean distance analysis was employed to determine the habitat preferences of Black-necked Cranes, and a local nearest-neighbor, convex-hull construction method was used to examine space use. Our results indicate that Black-necked Cranes preferred shallow marsh and wet meadow habitats and avoided farmland and dry grassland. Core-use areas (50% isopleths) and total-use areas (100% isopleths) accounted for only 1.2% and 28.2% of the study area, respectively. We recommend that habitat protection efforts focus on shallow marsh and wet meadow habitats to maintain preferred foraging sites. Core-use areas, such as the primary foraging areas of Black-necked Cranes, should be designated as part of the core zone of the nature reserve. Monthly shifts in the core-use areas of the cranes also indicate that the reserve should be large enough to permit changes in space use. In addition to preserving habitat, government officials should also take measures to decrease human activity in areas used by foraging Black-necked Cranes.
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Over the past 50 years, economic and technological developments have dramatically increased the human contribution to ambient noise in the ocean. The dominant frequencies of most human-made noise in the ocean is in the low-frequency range (defined as sound energy below 1000Hz), and low-frequency sound (LFS) may travel great distances in the ocean due to the unique propagation characteristics of the deep ocean (Munk et al. 1989). For example, in the Northern Hemisphere oceans low-frequency ambient noise levels have increased by as much as 10 dB during the period from 1950 to 1975 (Urick 1986; review by NRC 1994). Shipping is the overwhelmingly dominant source of low-frequency manmade noise in the ocean, but other sources of manmade LFS including sounds from oil and gas industrial development and production activities (seismic exploration, construction work, drilling, production platforms), and scientific research (e.g., acoustic tomography and thermography, underwater communication). The SURTASS LFA system is an additional source of human-produced LFS in the ocean, contributing sound energy in the 100-500 Hz band. When considering a document that addresses the potential effects of a low-frequency sound source on the marine environment, it is important to focus upon those species that are the most likely to be affected. Important criteria are: 1) the physics of sound as it relates to biological organisms; 2) the nature of the exposure (i.e. duration, frequency, and intensity); and 3) the geographic region in which the sound source will be operated (which, when considered with the distribution of the organisms will determine which species will be exposed). The goal in this section of the LFA/EIS is to examine the status, distribution, abundance, reproduction, foraging behavior, vocal behavior, and known impacts of human activity of those species may be impacted by LFA operations. To focus our efforts, we have examined species that may be physically affected and are found in the region where the LFA source will be operated. The large-scale geographic location of species in relation to the sound source can be determined from the distribution of each species. However, the physical ability for the organism to be impacted depends upon the nature of the sound source (i.e. explosive, impulsive, or non-impulsive); and the acoustic properties of the medium (i.e. seawater) and the organism. Non-impulsive sound is comprised of the movement of particles in a medium. Motion is imparted by a vibrating object (diaphragm of a speaker, vocal chords, etc.). Due to the proximity of the particles in the medium, this motion is transmitted from particle to particle in waves away from the sound source. Because the particle motion is along the same axis as the propagating wave, the waves are longitudinal. Particles move away from then back towards the vibrating source, creating areas of compression (high pressure) and areas of rarefaction (low pressure). As the motion is transferred from one particle to the next, the sound propagates away from the sound source. Wavelength is the distance from one pressure peak to the next. Frequency is the number of waves passing per unit time (Hz). Sound velocity (not to be confused with particle velocity) is the impedance is loosely equivalent to the resistance of a medium to the passage of sound waves (technically it is the ratio of acoustic pressure to particle velocity). A high impedance means that acoustic particle velocity is small for a given pressure (low impedance the opposite). When a sound strikes a boundary between media of different impedances, both reflection and refraction, and a transfer of energy can occur. The intensity of the reflection is a function of the intensity of the sound wave and the impedances of the two media. Two key factors in determining the potential for damage due to a sound source are the intensity of the sound wave and the impedance difference between the two media (impedance mis-match). The bodies of the vast majority of organisms in the ocean (particularly phytoplankton and zooplankton) have similar sound impedence values to that of seawater. As a result, the potential for sound damage is low; organisms are effectively transparent to the sound – it passes through them without transferring damage-causing energy. Due to the considerations above, we have undertaken a detailed analysis of species which met the following criteria: 1) Is the species capable of being physically affected by LFS? Are acoustic impedence mis-matches large enough to enable LFS to have a physical affect or allow the species to sense LFS? 2) Does the proposed SURTASS LFA geographical sphere of acoustic influence overlap the distribution of the species? Species that did not meet the above criteria were excluded from consideration. For example, phytoplankton and zooplankton species lack acoustic impedance mis-matches at low frequencies to expect them to be physically affected SURTASS LFA. Vertebrates are the organisms that fit these criteria and we have accordingly focused our analysis of the affected environment on these vertebrate groups in the world’s oceans: fishes, reptiles, seabirds, pinnipeds, cetaceans, pinnipeds, mustelids, sirenians (Table 1).
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This paper follows the work of A.V. Shanin on diffraction by an ideal quarter-plane. Shanin's theory, based on embedding formulae, the acoustic uniqueness theorem and spherical edge Green's functions, leads to three modified Smyshlyaev formulae, which partially solve the far-field problem of scattering of an incident plane wave by a quarter-plane in the Dirichlet case. In this paper, we present similar formulae in the Neumann case, and describe a numerical method allowing a fast computation of the diffraction coefficient using Shanin's third modified Smyshlyaev formula. The method requires knowledge of the eigenvalues of the Laplace-Beltrami operator on the unit sphere with a cut, and we also describe a way of computing these eigenvalues. Numerical results are given for different directions of incident plane wave in the Dirichlet and the Neumann cases, emphasising the superiority of the third modified Smyshlyaev formula over the other two. © 2011 Elsevier B.V.
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As a first step in reviewing the classification of the two stump-tailed macaque species, Macaca arctoides and M. thibetana, as compared with other species of the genus Macaca, 72 linear dental and cranial variables of 11 macaque species were examined by morphometric analyses. The results indicate that the two stump-tailed species are the largest of the macaques and although rather similar overall, they exhibit significant differences in the pattern of variation in most of the five skull regions as shown by Principal Components and Canonical Variate Analyses. Euclidean Distances based on Canonical Variate scores indicate that the females of M. arctoides and M. thibetana are more widely separated than eight other pairs of macaque species, and that the separations of the respective males are greater than those of three other pairs of species. These findings are consistent with FOODEN's classification of the stump-tailed macaques as two separate species (FOODEN, 1976; FOODEN et al., 1985). The present results suggest, as other researchers have proposed on the basis of external features, biochemistry and genetics, that the two stump-tailed macaque species and M. assamensis are closely related. The results also tentatively imply associations with M. fuscata and M. sylvanus but these require further study. The findings have implications for the assessment of the various Chinese Pleistocene macaque fossils.
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This paper presents a method for vote-based 3D shape recognition and registration, in particular using mean shift on 3D pose votes in the space of direct similarity transforms for the first time. We introduce a new distance between poses in this spacethe SRT distance. It is left-invariant, unlike Euclidean distance, and has a unique, closed-form mean, in contrast to Riemannian distance, so is fast to compute. We demonstrate improved performance over the state of the art in both recognition and registration on a real and challenging dataset, by comparing our distance with others in a mean shift framework, as well as with the commonly used Hough voting approach. © 2011 IEEE.
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A lattice Boltzmann method is used to model gas-solid reactions where the composition of both the gas and solid phase changes with time, while the boundary between phases remains fixed. The flow of the bulk gas phase is treated using a multiple relaxation time MRT D3Q19 model; the dilute reactant is treated as a passive scalar using a single relaxation time BGK D3Q7 model with distinct inter- and intraparticle diffusivities. A first-order reaction is incorporated by modifying the method of Sullivan et al. [13] to include the conversion of a solid reactant. The detailed computational model is able to capture the multiscale physics encountered in reactor systems. Specifically, the model reproduced steady state analytical solutions for the reaction of a porous catalyst sphere (pore scale) and empirical solutions for mass transfer to the surface of a sphere at Re=10 (particle scale). Excellent quantitative agreement between the model and experiments for the transient reduction of a single, porous sphere of Fe 2O 3 to Fe 3O 4 in CO at 1023K and 10 5Pa is demonstrated. Model solutions for the reduction of a packed bed of Fe 2O 3 (reactor scale) at identical conditions approached those of experiments after 25 s, but required prohibitively long processor times. The presented lattice Boltzmann model resolved successfully mass transport at the pore, particle and reactor scales and highlights the relevance of LB methods for modelling convection, diffusion and reaction physics. © 2012 Elsevier Inc.