972 resultados para generalized integral transforms
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El propósito de este estudio longitudinal prospectivo es abordar un plan integral de actividad física en niños y niñas entre 6 y 12 años que padezcan sobrepeso y obesidad. El programa se llevará a cabo en el Hospital de San Juan de Dios de Barcelona, donde se utilizarán una serie de variables de medida y tests que serán valorados antes, durante y después de este plan integral. Participarán dos profesionales de la salud, un fisioterapeuta y un nutricionista, quienes intervendrán en 20 niños y niñas con sobrepeso y obesidad. La finalidad de este estudio es disminuir el índice de masa corporal (IMC), así como el porcentaje de grasa corporal total (GCT) en los niños y niñas con sobrepeso y obesidad. También se pretende introducir y fomentar hábitos de vida saludables en relación a la actividad física y la alimentación en los niños y niñas y en su entorno familiar.
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The most suitable method for estimation of size diversity is investigated. Size diversity is computed on the basis of the Shannon diversity expression adapted for continuous variables, such as size. It takes the form of an integral involving the probability density function (pdf) of the size of the individuals. Different approaches for the estimation of pdf are compared: parametric methods, assuming that data come from a determinate family of pdfs, and nonparametric methods, where pdf is estimated using some kind of local evaluation. Exponential, generalized Pareto, normal, and log-normal distributions have been used to generate simulated samples using estimated parameters from real samples. Nonparametric methods include discrete computation of data histograms based on size intervals and continuous kernel estimation of pdf. Kernel approach gives accurate estimation of size diversity, whilst parametric methods are only useful when the reference distribution have similar shape to the real one. Special attention is given for data standardization. The division of data by the sample geometric mean is proposedas the most suitable standardization method, which shows additional advantages: the same size diversity value is obtained when using original size or log-transformed data, and size measurements with different dimensionality (longitudes, areas, volumes or biomasses) may be immediately compared with the simple addition of ln k where kis the dimensionality (1, 2, or 3, respectively). Thus, the kernel estimation, after data standardization by division of sample geometric mean, arises as the most reliable and generalizable method of size diversity evaluation
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A class of three-sided markets (and games) is considered, where value is generated by pairs or triplets of agents belonging to different sectors, as well as by individuals. For these markets we analyze the situation that arises when some agents leave the market with some payoff To this end, we introduce the derived market (and game) and relate it to the Davis and Maschler (1965) reduced game. Consistency with respect to the derived market, together with singleness best and individual anti-monotonicity axiomatically characterize the core for these generalized three-sided assignment markets. These markets may have an empty core, but we define a balanced subclass, where the worth of each triplet is defined as the addition of the worths of the pairs it contains. Keywords: Multi-sided assignment market, Consistency, Core, Nucleolus. JEL Classification: C71, C78
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La fuerte demanda de alimentos que ha tenido lugar a nivel mundial en los últimos años, ha provocadoun cambio en los sistemas de producción agraria y para el caso de la ganadera se ha pasado de lastípicas explotaciones extensivas ligadas al terreno a las granjas intensivas, en donde se ha incrementadola carga ganadera, bien aumentando el número de cabezas en pastoreo o mediante la construcción degranjas intensivas sin suelo
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This thesis deals with distance transforms which are a fundamental issue in image processing and computer vision. In this thesis, two new distance transforms for gray level images are presented. As a new application for distance transforms, they are applied to gray level image compression. The new distance transforms are both new extensions of the well known distance transform algorithm developed by Rosenfeld, Pfaltz and Lay. With some modification their algorithm which calculates a distance transform on binary images with a chosen kernel has been made to calculate a chessboard like distance transform with integer numbers (DTOCS) and a real value distance transform (EDTOCS) on gray level images. Both distance transforms, the DTOCS and EDTOCS, require only two passes over the graylevel image and are extremely simple to implement. Only two image buffers are needed: The original gray level image and the binary image which defines the region(s) of calculation. No other image buffers are needed even if more than one iteration round is performed. For large neighborhoods and complicated images the two pass distance algorithm has to be applied to the image more than once, typically 3 10 times. Different types of kernels can be adopted. It is important to notice that no other existing transform calculates the same kind of distance map as the DTOCS. All the other gray weighted distance function, GRAYMAT etc. algorithms find the minimum path joining two points by the smallest sum of gray levels or weighting the distance values directly by the gray levels in some manner. The DTOCS does not weight them that way. The DTOCS gives a weighted version of the chessboard distance map. The weights are not constant, but gray value differences of the original image. The difference between the DTOCS map and other distance transforms for gray level images is shown. The difference between the DTOCS and EDTOCS is that the EDTOCS calculates these gray level differences in a different way. It propagates local Euclidean distances inside a kernel. Analytical derivations of some results concerning the DTOCS and the EDTOCS are presented. Commonly distance transforms are used for feature extraction in pattern recognition and learning. Their use in image compression is very rare. This thesis introduces a new application area for distance transforms. Three new image compression algorithms based on the DTOCS and one based on the EDTOCS are presented. Control points, i.e. points that are considered fundamental for the reconstruction of the image, are selected from the gray level image using the DTOCS and the EDTOCS. The first group of methods select the maximas of the distance image to new control points and the second group of methods compare the DTOCS distance to binary image chessboard distance. The effect of applying threshold masks of different sizes along the threshold boundaries is studied. The time complexity of the compression algorithms is analyzed both analytically and experimentally. It is shown that the time complexity of the algorithms is independent of the number of control points, i.e. the compression ratio. Also a new morphological image decompression scheme is presented, the 8 kernels' method. Several decompressed images are presented. The best results are obtained using the Delaunay triangulation. The obtained image quality equals that of the DCT images with a 4 x 4
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We present parallel characterizations of two different values in the framework of restricted cooperation games. The restrictions are introduced as a finite sequence of partitions defined on the player set, each of them being coarser than the previous one, hence forming a structure of different levels of a priori unions. On the one hand, we consider a value first introduced in Ref. [18], which extends the Shapley value to games with different levels of a priori unions. On the other hand, we introduce another solution for the same type of games, which extends the Banzhaf value in the same manner. We characterize these two values using logically comparable properties.
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The author studies random walk estimators for radiosity with generalized absorption probabilities. That is, a path will either die or survive on a patch according to an arbitrary probability. The estimators studied so far, the infinite path length estimator and finite path length one, can be considered as particular cases. Practical applications of the random walks with generalized probabilities are given. A necessary and sufficient condition for the existence of the variance is given, together with heuristics to be used in practical cases. The optimal probabilities are also found for the case when one is interested in the whole scene, and are equal to the reflectivities
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We study cooperative and competitive solutions for a many- to-many generalization of Shapley and Shubik (1972)'s assignment game. We consider the Core, three other notions of group stability and two al- ternative definitions of competitive equilibrium. We show that (i) each group stable set is closely related with the Core of certain games defined using a proper notion of blocking and (ii) each group stable set contains the set of payoff vectors associated to the two definitions of competitive equilibrium. We also show that all six solutions maintain a strictly nested structure. Moreover, each solution can be identified with a set of ma- trices of (discriminated) prices which indicate how gains from trade are distributed among buyers and sellers. In all cases such matrices arise as solutions of a system of linear inequalities. Hence, all six solutions have the same properties from a structural and computational point of view.
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Of the many dimensions of the problem of violence exercised by men toward women in the context of the relations of partner or ex partner, this article deals with the analysis of the discursive productions of the institutional actors that are part of the judicial process. Our intention is to investigate the relationship between criminal law and gender-based violence starting from the implementation of the Law of Integral Gender-based Violence in Spain (LO. 1 / 2004) from a theoretical perspective which includes contributions from social psychology, and socio-legal feminism. We have approached the legal instrument - the Law of Integral Gender-based Violence - through the discourse of legal officers with a perspective that questions the values, so often proclaimed, of universality, objectivity and neutrality of the law
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We develop a method for obtaining 3D polarimetric integral images from elemental images recorded in low light illumination conditions. Since photon-counting images are very sparse, calculation of the Stokes parameters and the degree of polarization should be handled carefully. In our approach, polarimetric 3D integral images are generated using the Maximum Likelihood Estimation and subsequently reconstructed by means of a Total Variation Denoising filter. In this way, polarimetric results are comparable to those obtained in conventional illumination conditions. We also show that polarimetric information retrieved from photon starved images can be used in 3D object recognition problems. To the best of our knowledge, this is the first report on 3D polarimetric photon counting integral imaging.
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Básicamente las desviaciones de los dedos medios que a diario nos encontramos en las exploraciones podológicas, son de dos tipos: - Deformaciones longitudinales en el plano sagital: dedos en garra o en martillo con sus múltiples variantes. - Deformaciones laterales en el plano frontal: clinodactilias con dedos supra e infraductus.
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This work is devoted to the development of numerical method to deal with convection diffusion dominated problem with reaction term, non - stiff chemical reaction and stiff chemical reaction. The technique is based on the unifying Eulerian - Lagrangian schemes (particle transport method) under the framework of operator splitting method. In the computational domain, the particle set is assigned to solve the convection reaction subproblem along the characteristic curves created by convective velocity. At each time step, convection, diffusion and reaction terms are solved separately by assuming that, each phenomenon occurs separately in a sequential fashion. Moreover, adaptivities and projection techniques are used to add particles in the regions of high gradients (steep fronts) and discontinuities and transfer a solution from particle set onto grid point respectively. The numerical results show that, the particle transport method has improved the solutions of CDR problems. Nevertheless, the method is time consumer when compared with other classical technique e.g., method of lines. Apart from this advantage, the particle transport method can be used to simulate problems that involve movingsteep/smooth fronts such as separation of two or more elements in the system.
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This thesis studies properties of transforms based on parabolic scaling, like Curvelet-, Contourlet-, Shearlet- and Hart-Smith-transform. Essentially, two di erent questions are considered: How these transforms can characterize H older regularity and how non-linear approximation of a piecewise smooth function converges. In study of Hölder regularities, several theorems that relate regularity of a function f : R2 → R to decay properties of its transform are presented. Of particular interest is the case where a function has lower regularity along some line segment than elsewhere. Theorems that give estimates for direction and location of this line, and regularity of the function are presented. Numerical demonstrations suggest also that similar theorems would hold for more general shape of segment of low regularity. Theorems related to uniform and pointwise Hölder regularity are presented as well. Although none of the theorems presented give full characterization of regularity, the su cient and necessary conditions are very similar. Another theme of the thesis is the study of convergence of non-linear M ─term approximation of functions that have discontinuous on some curves and otherwise are smooth. With particular smoothness assumptions, it is well known that squared L2 approximation error is O(M-2(logM)3) for curvelet, shearlet or contourlet bases. Here it is shown that assuming higher smoothness properties, the log-factor can be removed, even if the function still is discontinuous.
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As exigências sociopolíticas atuais quanto à formação e ao perfil do profissional de saúde se ampliam para além da capacitação técnico-científica, requerendo profissionais capazes de um atendimento integral em equipe interdisciplinar/multiprofissional. Nesse contexto, o objetivo deste estudo foi, através da Educação a Distância, baseada em método fundamentado na teoria construtivista, promover cenários de interação visando à construção de uma prática/pensamento integral em saúde, com a participação de seis graduandos de Medicina e nove profissionais da saúde. Foi utilizado o Teleduc, um ambiente de aprendizagem a distância. O modelo de estudo foi definido como um estudo de caso, e a análise se baseou nas interações dos alunos, na participação nos fóruns de discussão, nas edições dos exercícios individuais e dos portfólios de grupo. O procedimento mostrou-se um valioso promotor de interação em saúde, possibilitando desequilíbrios, reflexões, postura cooperativa e mudanças de conduta, com geração de conhecimento integral em saúde. A análise evidenciou que, para construir relações de cooperação no virtual, são necessários elementos que otimizem as interações, conferindo qualidade pedagógica e proporcionando um contexto favorável, a fim de prolongar o aprendizado rumo a uma prática transformadora
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O uso problemático de álcool (UPA) é um dos principais problemas de saúde pública na lista de prioridades da Estratégia de Saúde da Família (ESF). Este artigo objetiva investigar a visão de enfermeiros e médicos de Saúde da Família sobre o UPA, focando a compreensão que trazem sobre esta temática e o modo como é trabalhada no dia a dia dos serviços da região amazônica. Trata-se de um estudo qualitativo, com 14 trabalhadores da ESF, médicos e enfermeiros recém-formados de um município do interior do Amazonas. Foram utilizados dois grupos focais. Os dados foram analisados por meio de análise temática, a partir dos princípios do SUS e da formação de recursos humanos em saúde. Os profissionais identificaram os fatores de risco para o UPA, mostraram conhecer as consequências para o indivíduo e para a sociedade, e descreveram os critérios utilizados pelos sistemas de classificação de doenças, mas não sabiam como atuar sobre esta questão, indicando problemas na formação universitária.