On a fast bilateral filtering formulation using functional rearrangements

We introduce an exact reformulation of a broad class of neighborhood filters, among which the bilateral filters, in terms of two functional rearrangements: the decreasing and the relative rearrangements. Independently of the image spatial dimension (one-dimensional signal, image, volume of images, etc.), we reformulate these filters as integral operators defined in a one-dimensional space corresponding to the level sets measures. We prove the equivalence between the usual pixel-based version and the rearranged version of the filter. When restricted to the discrete setting, our reformulation of bilateral filters extends previous results for the so-called fast bilateral filtering. We, in addition, prove that the solution of the discrete setting, understood as constant-wise interpolators, converges to the solution of the continuous setting. Finally, we numerically illustrate computational aspects concerning quality approximation and execution time provided by the rearranged formulation.Comment: 29 pages, Journal of Mathematical Imaging and Vision, 2015. arXiv admin note: substantial text overlap with arXiv:1406.712

Well-posedness of a nonlinear integro-differential problem and its rearranged formulation

We study the existence and uniqueness of solutions of a nonlinear integro-differential problem which we reformulate introducing the notion of the decreasing rearrangement of the solution. A dimensional reduction of the problem is obtained and a detailed analysis of the properties of the solutions of the model is provided. Finally, a fast numerical method is devised and implemented to show the performance of the model when typical image processing tasks such as filtering and segmentation are performed.Comment: Final version. To appear in Nolinear Analysis Real World Applications (2016

¿Son los derechos temporales concesiones temporales? ensayo de genealogía

This paper attempts to outline the “invention of the social” as a strategy whose goal was to neutralize the XIXth century work-capital antagonism. With this purpose in mind, we follow an archeological and genealogical procedure that takes into account both the epistemological transformations which made possible the advent of the new social rationality, and the power struggles in which those may be enshrined.El presente artículo trata de caracterizar la “invención de lo social” como una estrategia para neutralizar el antagonismo capital trabajo que domina el siglo XIX. Para ello, se sigue un método arqueológico y genealógico, que toma en consideración las transformaciones epistemológicas que posibilitaron el advenimiento de la racionalidad social, así como las luchas de poder en las que estas transformaciones deben ser enmarcadas

Relação entre peso do fígado, tamanho corporal e atividade reprodutiva em Atlantoraja cyclophora (Elasmobranchii: Rajidae: Arhynchobatinae) em águas oceânicas do Rio Grande do Sul, Brasil

Samples of Atlantoraja cyclophora were obtained by bottom-trawling surveys on the outer continental shelf and upper slope of the Rio Grande do Sul State, Brazil, at depths between 100 and 300 m. For a sample of 459 individuals, the total length, eviscerated weight and liver weight were recorded. Liver weight of the males varied between 2.4 and 36 g, and 2.4 and 65 for the females. Females had significantly heavier livers in all total length classes. For the males, the hepatosomatic index varied between 1.5 and 3.5 and for the females between 0.53 and 4.95. Mean hepatosomatic index was significantly higher in the females. Liver weight and total length according to the equations LW=0.00065*TL2.648 for males and LW=0.00309*TL2.171 for females. Key words: egg capsules, sexual dimorphism, yolk, reproductive stages.Amostras de Atlantoraja cyclophora foram obtidas através de cruzeiros de pesquisa com arrasto de fundo na plataforma continental externa e talude superior do estado do Rio Grande do Sul, Brasil, em profundidades entre 100 e 300 m. Para 459 indivíduos foram registrados o comprimento total, o peso eviscerado e o peso do fígado. Este último variou nos machos de entre 2.4 a 36 g e nas fêmeas de entre 2.4 a 65 g. As fêmeas tiveram fígados significativamente mais pesados que o dos machos em todas as classes de comprimento total. Nos machos, o índice hepatossomático variou de entre 1.5 e 3.5 e nas fêmeas de entre 0.53 e 4.95. O peso do fígado aumentou com relação ao o peso total segundo a relação LW=0.00065*TL2.648 nos machos e LW=0.00309*TL2.171 nas fêmeas. Palavras-chave: cápsulas ovígeras, dimorfismo sexual, vitelo, estágios reprodutivos