Search results for "value"

showing 10 items of 5321 documents

Weighted Extrapolation Techniques for Finite Difference Methods on Complex Domains with Cartesian Meshes

2016

The design of numerical boundary conditions in high order schemes is a challenging problem that has been tackled in different ways depending on the nature of the problem and the scheme used to solve it numerically. In this paper we propose a technique to extrapolate the information from the computational domain to ghost cells for schemes with structured Cartesian Meshes on complex domains. This technique is based on the application of Lagrange interpolation with weighted filters for the detection of discontinuities that permits a data dependent extrapolation, with high order at smooth regions and essentially non oscillatory properties near discontinuities. This paper is a sequel of Baeza et…

Discrete mathematicsComputer scienceMathematicsofComputing_NUMERICALANALYSISExtrapolationFinite difference methodLagrange polynomialBoundary (topology)Classification of discontinuitieslaw.inventionsymbols.namesakelawsymbolsApplied mathematicsPolygon meshCartesian coordinate systemBoundary value problem
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Single-valued extension property at the points of the approximate point spectrum

2003

Abstract A localized version of the single-valued extension property is studied at the points which are not limit points of the approximate point spectrum, as well as of the surjectivity spectrum. In particular, we shall characterize the single-valued extension property at a point λ o ∈ C in the case that λoI−T is of Kato type. From this characterizations we shall deduce several results on cluster points of some distinguished parts of the spectrum.

Discrete mathematicsFredholm theoryFredholm operatorApplied MathematicsSpectrum (functional analysis)Banach spaceExtension (predicate logic)Type (model theory)Fredholm theorySingle valued extension propertysymbols.namesakeLimit pointsymbolsPoint (geometry)AnalysisMathematicsJournal of Mathematical Analysis and Applications
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Operators Which Do Not Have the Single Valued Extension Property

2000

Abstract In this paper we shall consider the relationships between a local version of the single valued extension property of a bounded operator T  ∈  L ( X ) on a Banach space X and some quantities associated with T which play an important role in Fredholm theory. In particular, we shall consider some conditions for which T does not have the single valued extension property at a point λ o  ∈  C .

Discrete mathematicsFredholm theoryProperty (philosophy)Applied MathematicsFredholm operatorBanach spaceExtension (predicate logic)Fredholm theoryBounded operatorLinear mapsymbols.namesakesingle valued extension propertysymbolsAnalysisMathematicsResolventJournal of Mathematical Analysis and Applications
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On set-valued cone absolutely summing maps

2009

Spaces of cone absolutely summing maps are generalizations of Bochner spaces Lp(μ, Y), where (Ω, Σ, μ) is some measure space, 1 ≤ p ≤ ∞ and Y is a Banach space. The Hiai-Umegaki space \( \mathcal{L}^1 \left[ {\sum ,cbf(X)} \right] \) of integrably bounded functions F: Ω → cbf(X), where the latter denotes the set of all convex bounded closed subsets of a separable Banach space X, is a set-valued analogue of L1(μ, X). The aim of this work is to introduce set-valued cone absolutely summing maps as a generalization of \( \mathcal{L}^1 \left[ {\sum ,cbf(X)} \right] \) , and to derive necessary and sufficient conditions for a set-valued map to be such a set-valued cone absolutely summing map. We …

Discrete mathematicsGeneral MathematicsBanach spaceBochner spaceSpace (mathematics)Measure (mathematics)Separable spaceCombinatoricsBanach lattice Bochner space Cone absolutely summing operator Integrably bounded set-valued function Set-valued operatorNumber theoryCone (topology)Settore MAT/05 - Analisi MatematicaBounded functionMathematicsCentral European Journal of Mathematics
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Description of the limit set of Henstock–Kurzweil integral sums of vector-valued functions

2015

Abstract Let f be a function defined on [ 0 , 1 ] and taking values in a Banach space X . We show that the limit set I HK ( f ) of Henstock–Kurzweil integral sums is non-empty and convex when the function f has an integrable majorant and X is separable. In the same setting we give a complete description of the limit set.

Discrete mathematicsHenstock–Kurzweil integralApplied MathematicsMathematics::Classical Analysis and ODEsBanach spaceRiemann integralFunction (mathematics)Separable spacesymbols.namesakeSettore MAT/05 - Analisi MatematicaImproper integralsymbolsHenstock–Kurzweil integral Limit set of integral sums Multifunction Aumann integralLimit setVector-valued functionAnalysisMathematicsJournal of Mathematical Analysis and Applications
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A homotopy fixed point theorem in 0-complete partial metric space

2015

We generalize a result of Feng and Liu, on multi-valued contractive mappings, for studying the relationship between fixed point sets and homotopy fixed point sets. The presented results are discussed in the generalized setting of 0-complete partial metric spaces. An example and a nonlinear alternative of Leray-Schauder type are given to support our theorems.

Discrete mathematicsHomotopic mappings multi-valued mappings partial metric spacesGeneral MathematicsHomotopyFixed-point theoremProduct metricFixed pointType (model theory)Nonlinear systemMetric spaceSettore MAT/05 - Analisi MatematicaSettore MAT/03 - GeometriaCoincidence pointMathematics
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Fixed point and homotopy results for mixed multi-valued mappings in 0-complete partial metric spaces*

2015

We give sufficient conditions for the existence of common fixed points for a pair of mixed multi-valued mappings in the setting of 0-complete partial metric spaces. An example is given to demonstrate the usefulness of our results over the existing results in metric spaces. Finally, we prove a homotopy theorem via fixed point results.

Discrete mathematicsHomotopy categoryPartial metric spacefixed pointsApplied MathematicsInjective metric spacepartial metric spaceslcsh:QA299.6-433multi-valued mappingslcsh:AnalysisFixed pointFixed-point propertyIntrinsic metricConvex metric spacen-connectedMetric spaceSettore MAT/05 - Analisi Matematicamulti-valued mappingMetric (mathematics)AnalysisMathematics
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A Structural Theorem for Metric Space Valued Mappings of Φ-bounded Variation

2009

In this paper we introduce the notion of $\Phi$-bounded variation for metric space valued mappings defined on a subset of the real line. Such a notion generalizes the one for real functions introduced by M. Schramm, and many previous generalized variations. We prove a structural theorem for mappings of $\Phi$-bounded variation. As an application we show that each mapping of $\Phi$-bounded variation defined on a subset of $\mathbb{R}$ possesses a $\Phi$-variation preserving extension to the whole real line.

Discrete mathematicsInjective metric spaceextensionstructural theoremTotally bounded space54C35$\Phi$-bounded variation54E35Intrinsic metricmetric space valued mapings variation $Phi$-variation extension structural theorem.metric space valued mappingsUniform normSettore MAT/05 - Analisi MatematicaBounded functionBounded variationGeometry and Topologyvariation26A45Metric differentialReal lineAnalysisMathematics
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A Suzuki type fixed point theorem for a generalized multivalued mapping on partial Hausdorff metric spaces

2013

Abstract In this paper, we obtain a Suzuki type fixed point theorem for a generalized multivalued mapping on a partial Hausdorff metric space. As a consequence of the presented results, we discuss the existence and uniqueness of the bounded solution of a functional equation arising in dynamic programming.

Discrete mathematicsInjective metric spacepartial metric spaceFixed-point theoremFixed-point propertyCommon fixed pointSchauder fixed point theoremHausdorff distanceSettore MAT/05 - Analisi Matematicamulti-valued mappingContraction mappingGeometry and TopologyBrouwer fixed-point theoremKakutani fixed-point theoremMathematicsTopology and its Applications
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VECTOR-VALUED FUNCTIONS INTEGRABLE WITH RESPECT TO BILINEAR MAPS

2008

Let $(\Omega, \Sigma, \mu)$ be a $\sigma-$finite measure space, $1\le p \lt \infty$, $X$ be a Banach space $X$ and ${\cal B} :X\times Y \to Z$ be a bounded bilinear map. We say that an $X$-valued function $f$ is $p-$integrable with respect to ${\cal B}$ whenever $\sup\{\int_\Omega\|{\cal B}(f(w),y)\|^pd\mu: \|y\|=1\}$ is finite. We identify the spaces of functions integrable with respect to the bilinear maps arising from H\"older's and Young's inequalities. We apply the theory to give conditions on $X$-valued kernels for the boundedness of integral operators $T_{{\cal B}}(f) (w)=\int_{\Omega'}{{\cal B}}(k(w,w'),$ $f(w'))d\mu'(w')$ from ${\mathrm L}^p(Y)$ into ${\mathrm L}^p(Z)$, extending t…

Discrete mathematicsIntegrable systemGeneral MathematicsBanach spaceFunction (mathematics)Space (mathematics)Measure (mathematics)Omegavector-valued functionsbilinear mapBounded function42B3047B35Vector-valued functionMathematics
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