991 resultados para Algebra booleana
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The Companhia Energetica de Sao Paulo - CESP owns six hydroelectric dams in the state of São Paulo. The dams, both in its construction and in operation, cause some environmental impacts, most of them negatives, for example, the flooding in regions before not flooded, deviation of the river’s course, among others, bringing harm to flora and fauna of these environments. As a way to compensating these damages, the CESP has acquired a region that was influenced by Sérgio Motta Hydroelectric Plant Engineer, or Porto Primavera, and turned it into Reserva Particular do Patrimônio Natural Foz do Rio Aguapeí. By law it fits in a Conservation Unit, and thus should be contemplate for a management plan, ie, a multidisciplinary technical document which allows, simply, the practice of actions within and around in a sustainably way. This work aimed at developing a land cover map of the reserve for this plan can be made and executed more efficiently. Initially, the project included field visits and meetings with members of the CESP to be specified classes contained on the map. Later, we ran different types of classifications of multispectral images (TM / Landsat 5)... (Complete abstract click electronic access below)
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A crescente demanda por produtos de melhor qualidade, diferenciados e com custos competitivos tem forçado as manufaturas a se tornarem flexíveis, capacitando-as a responder às mudanças impostas pelo mercado. A flexibilidade permite que as empresas alcancem a customização desejada através da capacitação do sistema de responder e atuar em tempo real, mesmo em um ambiente de incertezas. Para atuar em tempo real, os sistemas de manufatura precisam de representações eficientes dos planos de produção. Muitas vezes, a atuação em tempo real torna-se inviável devido ao crescimento exponencial no número de planos de produção para cada máquina ou operação adicionada ao sistema. Uma possível solução para este problema é uso de representações adequadas para o espaço de estados. A escolha de uma representação adequada para o espaço de estados influencia na capacidade de reposta em tempo real, pois determina o desempenho computacional do sistema através da utilidade e eficiência dos algoritmos desenvolvidos, tornando possível explorar problemas clássicos de flexibilidade, tais como, seqüenciamento, otimização, etc. Entretanto, a geração de uma representação que trabalhe com o espaço de estados completo de uma manufatura é considerada um problema não polinomial (NP). Esta particularidade dificulta o desenvolvimento de algoritmos que trabalhem com uma manufatura flexível. Assim, a geração de uma representação, que trabalhe com pouca memória computacional e permita o desenvolvimento de heurísticas eficientes, é um importante desafio para uma avaliação efetiva da flexibilidade. Este trabalho objetiva o desenvolvimento de uma representação para o espaço de estados de uma manufatura com flexibilidade de seqüência. Na construção desta representação são aplicadas técnicas de modelagem baseadas na teoria dos grafos e nos princípios de álgebra booleana. Inicialmente, os grafos são utilizados para representar todas as seqüências de operações de uma manufatura, posteriormente estas seqüências são convertidas em formas normais disjuntivas (FND). Por fim, é apresentada uma possível aplicação da representação na FND em modelos de programação linear.
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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA
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Pós-graduação em Engenharia Elétrica - FEIS
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Given a separable unital C*-algebra C with norm parallel to center dot parallel to, let E-n denote the Banach-space completion of the C-valued Schwartz space on R-n with norm parallel to f parallel to(2)=parallel to < f, f >parallel to(1/2), < f, g >=integral f(x)* g(x)dx. The assignment of the pseudodifferential operator A=a(x,D) with C-valued symbol a(x,xi) to each smooth function with bounded derivatives a is an element of B-C(R-2n) defines an injective mapping O, from B-C(R-2n) to the set H of all operators with smooth orbit under the canonical action of the Heisenberg group on the algebra of all adjointable operators on the Hilbert module E-n. In this paper, we construct a left-inverse S for O and prove that S is injective if C is commutative. This generalizes Cordes' description of H in the scalar case. Combined with previous results of the second author, our main theorem implies that, given a skew-symmetric n x n matrix J and if C is commutative, then any A is an element of H which commutes with every pseudodifferential operator with symbol F(x+J xi), F is an element of B-C(R-n), is a pseudodifferential operator with symbol G(x - J xi), for some G is an element of B-C(R-n). That was conjectured by Rieffel.
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We describe the realization of the super-Reshetikhin-Semenov-Tian-Shansky (RS) algebra in quantum affine superalgebras, thus generalizing the approach of Frenkel and Reshetikhin to the supersymmetric (and twisted) case. The algebraic homomorphism between the super-RS algebra and the Drinfeld current realization of quantum affine superalgebras is established by using the Gauss decomposition technique of Ding and Frenkel. As an application, we obtain Drinfeld realization of quantum affine superalgebra U-q [osp(1/2)((1))] and its degeneration - central extended super-Yangian double DY(h over bar) [osp(1/2)((1))].
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We present an anisotropic correlated electron model on a periodic lattice, constructed from an R-matrix associated with the Temperley-Lieb algebra. By modification of the coupling of the first and last sites we obtain a model with quantum algebra invariance.
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By generalizing the Reshetikhin and Semenov-Tian-Shansky construction to supersymmetric cases, we obtain the Drinfeld current realization for the quantum affine superalgebra U-q[gl(m\n)((1))]. We find a simple coproduct for the quantum current generators and establish the Hopf algebra structure of this super current algebra.
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A matricial method to solve the decay chain differential equations system is presented. The quantity of each nuclide in the chain at a time t may be evaluated by analytical expressions obtained in a simple way using recurrence relations. This method may be applied to problems of radioactive buildup and decay and can be easily implemented computationally. (C) 2009 Elsevier B.V. All rights reserved.
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Motivated by application of twisted current algebra in description of the entropy of Ads(3) black hole, we investigate the simplest twisted current algebra sl(3, c)(k)((2)). Free field representation of the twisted algebra, and the corresponding twisted Sugawara energy-momentum tensor are obtained by using three (beta, gamma) pairs and two scalar fields. Primary fields and two screening currents of the first kind are presented. (C) 2001 Published by Elsevier Science B.V.
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Map algebra is a data model and simple functional notation to study the distribution and patterns of spatial phenomena. It uses a uniform representation of space as discrete grids, which are organized into layers. This paper discusses extensions to map algebra to handle neighborhood operations with a new data type called a template. Templates provide general windowing operations on grids to enable spatial models for cellular automata, mathematical morphology, and local spatial statistics. A programming language for map algebra that incorporates templates and special processing constructs is described. The programming language is called MapScript. Example program scripts are presented to perform diverse and interesting neighborhood analysis for descriptive, model-based and processed-based analysis.