Search results for "PD"

showing 10 items of 1971 documents

A Mönch type fixed point theorem under the interior condition

2009

Abstract In this paper we show that the well-known Monch fixed point theorem for non-self mappings remains valid if we replace the Leray–Schauder boundary condition by the interior condition. As a consequence, we obtain a partial generalization of Petryshyn's result for nonexpansive mappings.

Discrete mathematicsMathematics::Functional AnalysisGeneralizationApplied MathematicsInterior conditionMathematics::Analysis of PDEsBanach spaceFixed-point theoremType (model theory)Mönch fixed point theoremBanach spacesStrictly star-shaped setLeray–Schauder conditionBoundary value problemAnalysisMathematicsJournal of Mathematical Analysis and Applications
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Radon–Nikodym Property and Area Formula for Banach Homogeneous Group Targets

2013

We prove a Rademacher-type theorem for Lipschitz mappings from a subset of a Carnot group to a Banach homogeneous group, equipped with a suitably weakened Radon-Nikodym property. We provide a metric area formula that applies to these mappings and more generally to all almost everywhere metrically differentiable Lipschitz mappings defined on a Carnot group. peerReviewed

Discrete mathematicsMathematics::Functional AnalysisProperty (philosophy)General Mathematicsmetric area formulata111Mathematics::Analysis of PDEsCarnot groupBanach homogeneous groupsalmost everywhere differentiabilityRadon-Nikodym propertyLipschitz continuityRadon–Nikodym theoremBanach homogeneous groups; metric area formula; almost everywhere differentiability; Radon-Nikodym propertyMetric (mathematics)Homogeneous groupMathematics::Metric GeometryAlmost everywhereDifferentiable functionMathematics
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Shrinking and boundedly complete Schauder frames in Fréchet spaces

2014

We study Schauder frames in Fréchet spaces and their duals, as well as perturbation results. We define shrinking and boundedly complete Schauder frames on a locally convex space, study the duality of these two concepts and their relation with the reflexivity of the space. We characterize when an unconditional Schauder frame is shrinking or boundedly complete in terms of properties of the space. Several examples of concrete Schauder frames in function spaces are also presented.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsShrinkingReflexivitySchauder basisFunction space(LB)-spacesApplied MathematicsMathematics::Analysis of PDEsConvex setMathematics::General TopologyFréchet spacesSchauder basisAtomic decompositionSchauder fixed point theoremSchauder frameLocally convex spacesLocally convex topological vector spaceBoundedly completeDual polyhedronAtomic decompositionMATEMATICA APLICADAAnalysisMathematics
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A weak comparison principle for solutions of very degenerate elliptic equations

2012

We prove a comparison principle for weak solutions of elliptic quasilinear equations in divergence form whose ellipticity constants degenerate at every point where \(\nabla u\in K\), where \(K\subset \mathbb{R }^N\) is a Borel set containing the origin.

Discrete mathematicsPure mathematicsApplied MathematicsDegenerate energy levelsWeak comparison principleMathematics::Analysis of PDEs35B51 35J70 35D30 49K20Mathematics - Analysis of PDEsSettore MAT/05 - Analisi Matematicavery degenerate elliptic equationsFOS: MathematicsPoint (geometry)Nabla symbolBorel setDivergence (statistics)Analysis of PDEs (math.AP)MathematicsAnnali di Matematica Pura ed Applicata (1923 -)
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The p-Laplacian with respect to measures

2013

We introduce a definition for the $p$-Laplace operator on positive and finite Borel measures that satisfy an Adams-type embedding condition.

Discrete mathematicsPure mathematicsApplied Mathematicsta111Mathematics::Algebraic Topology35J92 35P30 35D99 35B65Mathematics - Analysis of PDEsAnalysis on fractalsp-LaplacianFOS: MathematicsEmbeddingLaplace operatorAnalysisMathematicsAnalysis of PDEs (math.AP)Journal of mathematical analysis and applications
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Geometric Properties of Planar BV -Extension Domains

2009

We investigate geometric properties of those planar domains that are extension for functions with bounded variation.We start from a characterization of such domains given by Burago–Maz'ya and prove that a bounded, simply connected domain is a BV -extension domain if and only if its com- plement is quasiconvex. We further prove that the extension property is a bi-Lipschitz invariant and give applications to Sobolev extension domains.

Discrete mathematicsQuasiconformal mappingMathematics::Analysis of PDEsGeometric propertySobolev spaceQuasiconvex functionExtension domains; Sobolev spaces; Functions with bounded variationPlanarSobolev spacesFunctions with bounded variationBounded functionSimply connected spaceInvariant (mathematics)Extension domainsMathematics
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Conditional Random Quantities and Iterated Conditioning in the Setting of Coherence

2013

We consider conditional random quantities (c.r.q.’s) in the setting of coherence. Given a numerical r.q. X and a non impossible event H, based on betting scheme we represent the c.r.q. X|H as the unconditional r.q. XH + μH c , where μ is the prevision assessed for X|H. We develop some elements for an algebra of c.r.q.’s, by giving a condition under which two c.r.q.’s X|H and Y|K coincide. We show that X|HK coincides with a suitable c.r.q. Y|K and we apply this representation to Bayesian updating of probabilities, by also deepening some aspects of Bayes’ formula. Then, we introduce a notion of iterated c.r.q. (X|H)|K, by analyzing its relationship with X|HK. Our notion of iterated conditiona…

Discrete mathematicsSettore MAT/06 - Probabilita' E Statistica MatematicaSettore INF/01 - Informaticaconditional random quantitiesCoherence (statistics)Bayesian inferencebayesian updatingcoherenceCombinatoricsconditional previsionsBayes' theoremIterated functionbayesian updating; conditional random quantities; betting scheme; conditional previsions; coherence; iterated conditioning; iterated conditioning.Coherence betting scheme conditional random quantities conditional previsions Bayesian updating iterated conditioning.Scheme (mathematics)iterated conditioningConditioningRepresentation (mathematics)betting schemeEvent (probability theory)Mathematics
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Extensions and Imbeddings

1998

AbstractWe establish a connection between the Sobolev imbedding theorem and the extendability of Sobolev functions. As applications we give geometric criteria for extendability and give a result on the dependence of the extension property on the exponentp.

Discrete mathematicsSobolev spacePure mathematicsMathematics::Functional AnalysisProperty (philosophy)Mathematics::Analysis of PDEsExtension (predicate logic)AnalysisConnection (mathematics)Sobolev inequalityMathematicsJournal of Functional Analysis
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Weighted norm inequalities in a bounded domain by the sparse domination method

2019

AbstractWe prove a local two-weight Poincaré inequality for cubes using the sparse domination method that has been influential in harmonic analysis. The proof involves a localized version of the Fefferman–Stein inequality for the sharp maximal function. By establishing a local-to-global result in a bounded domain satisfying a Boman chain condition, we show a two-weight p-Poincaré inequality in such domains. As an application we show that certain nonnegative supersolutions of the p-Laplace equation and distance weights are p-admissible in a bounded domain, in the sense that they support versions of the p-Poincaré inequality.

Discrete mathematicsosittaisdifferentiaaliyhtälötInequalityGeneral Mathematicsmedia_common.quotation_subject010102 general mathematicsPoincaré inequalityharmoninen analyysi01 natural sciences35A23 (Primary) 42B25 42B37 (Secondary)Harmonic analysis010104 statistics & probabilitysymbols.namesakeMathematics - Analysis of PDEsNorm (mathematics)Bounded functionFOS: MathematicssymbolsMaximal function0101 mathematicsepäyhtälötAnalysis of PDEs (math.AP)Mathematicsmedia_common
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Widening the applicability of AnMBR for urban wastewater treatment through PDMS membranes for dissolved methane capture: Effect of temperature and hy…

2021

[EN] AnMBR technology is a promising alternative to achieve future energy-efficiency and environmental-friendly urban wastewater (UWW) treatment. However, the large amount of dissolved methane lost in the effluent represents a potential high environmental impact that hinder the feasibility of this technology for full-scale applications. The use of degassing membranes (DM) to capture the dissolved methane from AnMBR effluents can be considered as an interesting alternative to solve this problem although further research is required to assess the suitability of this emerging technology. The aim of this study was to assess the effect of operating temperature and hydrodynamics on the capture of…

Dissolved methane captureEnvironmental EngineeringGreenhouse gas (GHG) emissions0208 environmental biotechnology02 engineering and technology010501 environmental sciencesManagement Monitoring Policy and LawWastewater01 natural sciencesWaste Disposal FluidMethaneWater Purificationchemistry.chemical_compoundBioreactorsOperating temperatureMass transferAnaerobiosisDimethylpolysiloxanesWaste Management and DisposalEffluentTECNOLOGIA DEL MEDIO AMBIENTE0105 earth and related environmental sciencesPDMS degassing MembraneEnergy recoveryFoulingAnaerobic membrane bioreactor (AnMBR)Membrane foulingUrban wastewaterTemperatureMembranes ArtificialGeneral MedicinePulp and paper industry020801 environmental engineeringWastewaterchemistryHydrodynamicsEnvironmental scienceMethaneJournal of environmental management
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