Search results for "total variation"

showing 6 items of 26 documents

Solutions to the 1-harmonic flow with values into a hyper-octant of the N-sphere

2013

Abstract We announce existence results for the 1-harmonic flow from a domain of R m into the first hyper-octant of the N -dimensional unit sphere, under homogeneous Neumann boundary conditions. The arguments rely on a notion of “geodesic representative” of a BV-vector field on its jump set.

Unit spheren-sphereGeodesicApplied MathematicsMathematical analysisA domainharmonic flowsOctant (solid geometry)non-convex variational problems1-harmonic flowlower semi-continuity and relaxation; total variation flow; 1-harmonic flow; non-convex variational problems; image processing; geodesic; partial differential equations; harmonic flowsimage processingHomogeneoustotal variation flowNeumann boundary conditionJumppartial differential equationslower semi-continuity and relaxationgeodesicMathematics
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THE 1-HARMONIC FLOW WITH VALUES IN A HYPEROCTANT OF THE N-SPHERE

2014

We prove the existence of solutions to the 1-harmonic flow — that is, the formal gradient flow of the total variation of a vector field with respect to the [math] -distance — from a domain of [math] into a hyperoctant of the [math] -dimensional unit sphere, [math] , under homogeneous Neumann boundary conditions. In particular, we characterize the lower-order term appearing in the Euler–Lagrange formulation in terms of the “geodesic representative” of a BV-director field on its jump set. Such characterization relies on a lower semicontinuity argument which leads to a nontrivial and nonconvex minimization problem: to find a shortest path between two points on [math] with respect to a metric w…

Unit spherenonconvex variational problemsriemannian manifolds with boundaryGeodesicn-sphereharmonic flows68U1053C2253C4435K9235K67Neumann boundary conditionpartial differential equations49J45MathematicsNumerical Analysisnonlinear parabolic systems; lower semicontinuity and relaxation; total variation flow; 1-harmonic flow; image processing; harmonic flows; partial differential equations; image processing.; geodesics; riemannian manifolds with boundary; nonconvex variational problemslower semicontinuity and relaxation58E20Applied MathematicsMathematical analysis49Q201-harmonic flowimage processingFlow (mathematics)35K55Metric (mathematics)total variation flowVector fieldnonlinear parabolic systemsBalanced flowAnalysisgeodesics
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Regularization of chattering phenomena via bounded variation controls

2018

In control theory, the term chattering is used to refer to strong oscillations of controls, such as an infinite number of switchings over a compact interval of times. In this paper we focus on three typical occurences of chattering: the Fuller phenomenon, referring to situations where an optimal control switches an infinite number of times over a compact set; the Robbins phenomenon, concerning optimal control problems with state constraints, meaning that the optimal trajectory touches the boundary of the constraint set an infinite number of times over a compact time interval; the Zeno phenomenon, referring as well to an infinite number of switchings over a compact set, for hybrid optimal co…

[ MATH.MATH-OC ] Mathematics [math]/Optimization and Control [math.OC]0209 industrial biotechnologyState constraintsBoundary (topology)02 engineering and technologyInterval (mathematics)01 natural sciences020901 industrial engineering & automationShooting methodConvergence (routing)FOS: MathematicsApplied mathematicsHybrid problems0101 mathematicsElectrical and Electronic EngineeringMathematics - Optimization and ControlMathematicsTotal variation010102 general mathematics[MATH.MATH-OC] Mathematics [math]/Optimization and Control [math.OC]Optimal controlComputer Science ApplicationsControllabilityControl and Systems EngineeringOptimization and Control (math.OC)Chattering controlBounded variationTrajectory[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC]Fuller phenomenon
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Modified total variation regularization using fuzzy complement for image denoising

2015

In this paper, we propose a denoising algorithm based on the Total Variation (TV) model. Specifically, we associate to the regularization term of the Rodin-Osher-Fatimi (ROF) functional a small weight whenever denoising is performed in edge and texture regions, which means less regularization and more details preservation. On the other hand, a large weight is associated if the region being filtered is smooth which means noise will be well suppressed. The weight computation is inspired from the fuzzy edge complement. Experiments on well-known images and comparison with state of the art denoising algorithms demonstrate that the proposed method not only presents good denoising performance but …

fuzzy complementbusiness.industryNoise reductionPattern recognitionTotal variation denoisingNon-local meansRegularization (mathematics)Fuzzy logicElectronic mailtotal variationComputer Science::Computer Vision and Pattern RecognitiondenoisingComputer visionVideo denoisingArtificial intelligenceNoise (video)edge detectorbusinessMathematics2015 International Conference on Image and Vision Computing New Zealand (IVCNZ)
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Broglie and Young, visionaries who shed light in the polar topology that grounds our reality: a hypothesis

2020

Una observación matemática que relaciona los patrones fractales y la operación de convolución en el contexto del procesamiento de imágenes digitales interrumpió una investigación que nos lleva a plantear la hipótesis de que el concepto de onda de materia (o dualidad onda-partícula) se encuentra en la dicotomía entre el par débil y un topología fuerte en el ámbito del marco de atractores singulares continuos en ninguna parte diferenciables y el concepto de fotón-solitón de Vigier. Tal inferencia parece ser más evidente en la interpretación de Broglie-Bohm de la mecánica cuántica en el cruce de características locales x globales. De esto se deduce también que la relación de los fenómenos natu…

staircase functionsreproducing kernelnormally hyperbolic invariant manifoldsnormal topologyUNESCO::FÍSICAtotal variation filteringconvergence of power seriessmall-divisorssurface of controlevel-set methods:FÍSICA [UNESCO]lebesgue-cantor measurearithmetic physicsinteracting ieldperturbation theory
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On elliptic equations involving the 1-Laplacian operator

2018

El objetivo de esta tesis doctoral es dar a conocer los resultados obtenidos sobre existencia, unicidad y regularidad de las soluciones de diferentes ecuaciones elípticas regidas por el operador 1-laplaciano. El primer capítulo está dedicado al estudio de la ecuación - div (Du/|Du|) + g(u) |Du| = f(x) en un subconjunto abierto y acotado U de R^N con frontera Lipschitz, con la condición de Dirichlet u=0 en la frontera, tomando una función f positiva y siendo g una función real, continua y positiva. Por un lado, obtenemos soluciones no acotadas cuando el dato f pertenece al espacio de Marcinkiewicz L^{N,\infty}(U), por lo que debemos introducir la definición apropiada para este tipo de soluci…

total variation termdynamical boundary conditionsl-laplacian operatornonlinear elliptic equations
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