Isomorphism of Intransitive Linear Lie Equations

We show that formal isomorphism of intransitive linear Lie equations along transversal to the orbits can be extended to neighborhoods of these transversal. In analytic cases, the word formal is dropped from theorems. Also, we associate an intransitive Lie algebra with each intransitive linear Lie equation, and from the intransitive Lie algebra we recover the linear Lie equation, unless of formal isomorphism. The intransitive Lie algebra gives the structure functions introduced by E. Cartan

Lead extrusion analysis by finite volume method

Computational numerical simulation is nowadays largely applied in the design and analysis of metal forming process. Extrusion of metals is one main forming process largely applied in the manufacturing of metallic products or parts. Historically, the Finite Element Method has been applied for decades in metal extrusion analysis [4]. However, recently in the academy, there is a trend to use Finite Volume Method: literature suggests that metal flow by extrusion can be analyzed by the flow formulation [1, 2]. Thus, metal flow can be modelled such us an incompressible viscous fluid [2]. This hypothesis can be assumed because extrusion process is an isochoric process. The MacCormack Method is commonly used to simulate compressible fluid flow by the finite volume method [3]. However, metal extrusion and incompressible fluid flow do not present state equations for the evolution of pressure, and therefore, a velocity-pressure coupling method is necessary to obtain a consistent velocity and pressure fields [3]. Present work proposes a new numerical scheme to obtain information about metal flow in the extrusion process, in steady state. The governing equations were discretized by Finite Volume Method, using the Explicit MacCormack Method to structured and collocated mesh. The SIMPLE Method was applied to attain pressure-velocity coupling [3]. These new numerical scheme was applied to forward extrusion process of lead. The incompressible metal extrusion velocity fields achieved faster convergence and a good agreement with analytical and experimental results obtained from literature. The MacCormack Method applied for metals produced consistent results without the need of artificial viscosity as employed by the compressible flow simulation approaches. Furthermore, the present numerical results also suggest that MacCormack Method and SIMPLE can be applied in the solution of metal forming processes besides the traditional application for compressible fluid flow

Aluminium extrusion analysis by the finite volume method

Present work proposes a novel numerical scheme to calculate stress and velocity fields of metal flow in axisymmetric extrusion process in steady state. Extrusion of aluminium is one main metal forming process largely applied in manufacturing bars and products with complex cross section shape. The upper-bound, slab, slip-line methods and more recently the numerical methods such as the Finite Element Method have been commonly applied in aluminium extrusion analysis. However, recently in the academy, the Finite Volume Method has been developed for metal flow analysis: literature suggests that extrusion of metals can be modelled by the flow formulation. Hence, metal flow can be mathematically modelled such us an incompressible non linear viscous fluid, owing to volume constancy and varying viscosity in metal forming. The governing equations were discretized by the Finite Volume Method, using the Explicit MacCormack Method in structured and collocated mesh. The MacCormack Method is commonly used to simulate compressible fluid flow by the finite volume method. However, metal plastic flow and incompressible fluid flow do not present state equations for the evolution of pressure, and therefore, a velocity-pressure coupling method is necessary to obtain a consistent velocity and pressure fields. The SIMPLE Method was applied to attain pressure-velocity coupling. This new numerical scheme was applied to forward hot extrusion process of an aluminium alloy. The metal extrusion velocity fields achieved fast convergence and a good agreement with experimental results. The MacCormack Method applied to metal extrusion produced consistent results without the need of artificial viscosity as employed by the compressible flow simulation approaches. Therefore, present numerical results also suggest that MacCormack method together with SIMPLE method can be applied in the solution of metal forming processes in addition to the traditional application for compressible fluid flow

Structural Analysis of the Formal and Informal Jobs in the Brazilian Economy

The reorganization of the Brazilian economy, in the globalization process, has brought out changes in its productive structure, and, consequently, changes in the job market. These changes had impact on the employment at the sectoral level, with great concerns related to the labor relations and to the growing unemployment rates. In the 1990s, the change in the focus of the development strategy, from a closed protected economy to an open economy with monetary control, has originated deep changes in the labor market. The number of employed persons in the primary and secondary sector was reduced, while in the tertiary sector there was an increase in the number of jobs, but not enough to absorb all the employees released from the previous two sectors. Besides the reduction in the capability of the economy to create new jobs, the last decade of the previous century has also showed an increase in the number of informal jobs. The share of informal jobs in the Brazilian economy was around 52% in 2003. In this way, the question of employment generated by the economic sectors, in number and quality, has become a crucial issue. The goal of this work is to study the characteristics and the evolution of the occupied persons, and to relate it with the formal and informal job market, as well as the economy productive structure, using for that input-output matrices constructed for the Brazilian economy. The main results show that there was a reduction in the capacity of the economy to generate employment for every million of Reais produced in a given sector. The data also shows that despite the ratio of informal workers in the economy being superior to the workers in the formality, the formal sector was responsible for about 60% of the jobs generated in the period of analysis.

The evolutionary ecology of interactive synchronism: The illusion of the optimal phenotype

In this article, we discuss some ecological-evolutionary strategies that allow synchronization of organisms, resources, and conditions. Survival and reproduction require synchronization of life cycles of organisms with favourable environmental and ecological features and conditions. This interactive synchronization can occur directly, through pairwise or diffuse co-evolution, or indirectly, for example, as a result of actions of ecosystem engineers and facilitator species. Observations of specific interactions, especially those which have coevolved, may give the false impression that evolution results in optimal genotypes or phenotypes. However, some phenotypes may arise under evolutionary constraints, such as simultaneous evolution of multiple traits, lack of a chain of fit transitional forms leading to an optimal phenotype, or by limits inherent in the process of selection, set by the number of selective deaths and by interference between linked variants. Although there are no optimal phenotypes, optimization models applied to particular species may be useful for a better understanding of the nature of adaptations. The evolution of adaptive strategies results in variable life histories. These strategies can minimize adverse impacts on the fitness of extreme or severe environmental conditions on survival and reproduction, and may include reproductive strategies such as semelparity and iteroparity, or morphological, physiological, or behavioural traits such as diapause, seasonal polyphenism, migration, or bet-hedging. However, natural selection cannot indefinitely maintain intra-population variation, and lack of variation can ultimately extinguish populations

A politics of conversion: nihilism and love in Toni Morrison's fiction

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Letras.O estudo Uma Política de Conversão: Niilismo e Amor na Ficção de Toni Morrison começa com a idéia de que a Literatura Afro-Americana apresenta um sentido de auto-reflexividade e hibridismo, através do qual autobiografia dialoga com romance, o espiritual se funde com o político. A partir deste traço dialógico a auto-reflexividade é politicamente estabelecida entre niilismo e amor. Na política de conversão, o estudo analisa as formas como mulheres negras, individualmente ou em grupo, fogem da escravidão para a liberdade, avançam da individualidade para a coletividade, ou substituem niilismo por amor. Metodologicamente o estudo apresenta sete capítulos. O primeiro discute os aspectos dialógicos que ilustram as conexões entre narrativas espirituais, de escravos e ficção, entre espiritualidade e política. O segundo examina o diálogo entre a conversão, pregação pública e formação da comunidade em Diário e Experiências Religiosas de Lee. O capítulo sugere que ao afirmar espiritualidade e humanidade a narradora abre profundo espaço para a mulher negra reclamar direitos civis. O terceiro discute o diálogo no interior da política de conversão entre narrativa de escravos e ficção. Este diálogo lida com niilismo e amor em Incidentes de Jacobs e Amada, Sula e O Olho Mais Azul de Morrison. Para a análise de niilismo e amor valores individuais e coletivos são considerados em relação a cinco aspectos: ambiente e agente antagonistas, agente de apoio, propósito da personagem e resultado alcançado. É visível, no estudo, o apoio que certas mulheres recebem de suas comunidades para contra-atacar antagonistas. O apoio nem sempre resulta na superação do niilismo e, por isso, derrota temporária pode ocorrer antes que elas sejam reintegradas à comunidade, como acontece com Linda Brent. O quarto capítulo examina as fraquezas e as energias da política da conversão e a reintegração de Sethe Suggs à comunidade de Bluestone Road. O quinto avalia como a comunidade de Bottom tenta controlar a individualidade de Sula Peace e como um grupo de mulheres lideradas por Nel Wrights consegue resgatar o espírito de independência da heroína. O sexto mostra como a política da conversão das mulheres de Lorain é incapaz de garantir a saúde mental de Pecola Breedlove, mas consegue criar um papel mais consistente para o grupo. No sétimo, a conclusão examina da relação dialética entre niilismo e amor ou auto-amor nas experiências dos indivíduos e dos grupos. O estudo sugere que em Incidentes a busca de Linda Brent por liberdade envolve elementos de autodestruição e de autoempoderamento. Da mesma maneira, o estudo conclui que em Amada o amor que Sethe Suggs tem para as suas crianças mata a própria filha, enfatizando, assim, o desejo de livrá-la da escravidão. Igualmente em Sula, a individualidade de Sula Peace não apenas limita, mas também expande as experiências do grupo, levando-o à emancipação. Finalmente, em O Olho Mais Azul a luta de Pecola Breedlove por amor e beleza reflete auto-ódio ao mesmo tempo em que reconstrói a auto-apreciação de toda a comunidade

Irreversible hypersomnolence after bilateral thalamic infarction

info:eu-repo/semantics/publishedVersio