Search results for " Analisi"

showing 10 items of 1252 documents

Homoclinic Solutions of Nonlinear Laplacian Difference Equations Without Ambrosetti-Rabinowitz Condition

2021

The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using Ambrosetti-Rabinowitz type-conditions. The main tools are mountain pass theorem and Palais-Smale compactness condition involving suitable functionals.

Nonlinear systemCompact spaceSettore MAT/05 - Analisi MatematicaDifferential equationGeneral MathematicsMountain pass theoremMathematical analysisMathematics::Analysis of PDEsGeneral Physics and AstronomyHomoclinic orbitLaplace operator(p q)-Laplacian operator Difference equations homoclinic solutions non-zero solutionsMathematicsActa Mathematica Scientia
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Two Nontrivial Solutions for Robin Problems Driven by a p–Laplacian Operator

2020

By variational methods and critical point theorems, we show the existence of two nontrivial solutions for a nonlinear elliptic problem under Robin condition and when the nonlinearty satisfies the usual Ambrosetti-Rabinowitz condition.

Nonlinear systemPure mathematicsRobin problemSettore MAT/05 - Analisi Matematicap-LaplacianCritical point theoryMathematics::Analysis of PDEsp-LaplacianRobin problem p-Laplacian Critical point theoryCritical point (mathematics)Mathematics
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Pairs of nontrivial smooth solutions for nonlinear Neumann problems

2020

Abstract We consider a nonlinear Neumann problem driven by a nonhomogeneous differential operator with a reaction term that exhibits strong resonance at infinity. Using variational tools based on the critical point theory, we prove the existence of two nontrivial smooth solutions.

Nonlinear systemStrong resonanceSettore MAT/05 - Analisi MatematicaApplied MathematicsC_c-conditionMathematical analysisNeumann boundary conditionDifferential operatorCritical point (mathematics)Second deformation theoremMathematicsNonlinear regularity
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Semilinear Robin problems driven by the Laplacian plus an indefinite potential

2019

We study a semilinear Robin problem driven by the Laplacian plus an indefinite potential. We consider the case where the reaction term f is a Carathéodory function exhibiting linear growth near ±∞. So, we establish the existence of at least two solutions, by using the Lyapunov-Schmidt reduction method together with variational tools.

Numerical AnalysisApplied Mathematics010102 general mathematicsFunction (mathematics)Mathematics::Spectral Theory01 natural sciencesTerm (time)010101 applied mathematicsComputational MathematicsSettore MAT/05 - Analisi MatematicaApplied mathematicsLyapunov-Schmidt reduction methodindefinite potential0101 mathematicsCarathéodory reactionLinear growthSemilinear Robin problemLaplace operatorAnalysisMathematicsComplex Variables and Elliptic Equations
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The local boundedness of solutions for a class of degenerate nonlinear elliptic higher-order equations withL1-data

2008

We prove local boundedness of solutions for a class of degenerate nonlinear elliptic higher-order equations with L(1)-data.

Numerical AnalysisClass (set theory)Higher order equationsHigher-order equationApplied MathematicsMathematical analysisDegenerate energy levelsWeighted functionComputational MathematicsNonlinear systemSettore MAT/05 - Analisi MatematicaLocal boundednessBoundedness of solutionsApplied mathematicsAnalysisMathematicsComplex Variables and Elliptic Equations
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CQ *-algebras of measurable operators

2022

Abstract We study, from a quite general point of view, a CQ*-algebra (X, 𝖀0) possessing a sufficient family of bounded positive tracial sesquilinear forms. Non-commutative L 2-spaces are shown to constitute examples of a class of CQ*-algebras and any abstract CQ*-algebra (X, 𝖀0) possessing a sufficient family of bounded positive tracial sesquilinear forms can be represented as a direct sum of non-commutative L 2-spaces.

Numerical AnalysisControl and OptimizationBanach C*-modules Non commutative integration Partial algebras of operators.Settore MAT/05 - Analisi MatematicaApplied MathematicsAnalysisMoroccan Journal of Pure and Applied Analysis
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A normalized iterative Smoothed Particle Hydrodynamics method

2020

Abstract In this paper we investigate on a normalized iterative approach to improve the Smoothed Particle Hydrodynamics (SPH) estimate of a function. The method iterates on the residuals of an initial SPH approximation to obtain a more accurate solution. The iterative strategy preserves the matrix-free nature of the method, does not require changes on the kernel function and it is not affected by disordered data distribution. The iterative refinement is further improved by ensuring linear approximation order to the starting iterative values. We analyze the accuracy and the convergence of the method with the standard and normalized formulation giving evidence of the enhancements obtained wit…

Numerical AnalysisGeneral Computer ScienceApplied Mathematics010103 numerical & computational mathematics02 engineering and technologyFunction (mathematics)01 natural sciencesDomain (mathematical analysis)Theoretical Computer ScienceSmoothed-particle hydrodynamicsSettore MAT/08 - Analisi NumericaDistribution (mathematics)Iterated residuals Normalized Smoothed Particle Hydrodynamics Accuracy ConvergenceIterated functionIterative refinementModeling and SimulationConvergence (routing)0202 electrical engineering electronic engineering information engineeringApplied mathematics020201 artificial intelligence & image processingLinear approximation0101 mathematicsMathematics
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Localization of the spectra of dual frames multipliers

2022

This paper concerns dual frames multipliers, i.e. operators in Hilbert spaces consisting of analysis, multiplication and synthesis processes, where the analysis and the synthesis are made by two dual frames, respectively. The goal of the paper is to give some results about the localization of the spectra of dual frames multipliers, i.e. to individuate regions of the complex plane containing the spectra using some information about the frames and the symbols.

Numerical AnalysisMatematikApplied MathematicsFunctional Analysis (math.FA)spectrumMathematics - Functional Analysisdual framesSettore MAT/05 - Analisi MatematicaFOS: Mathematicsmultipliers42C15 47A10 47A12multipliers;dual frames;spectrumAnalysisMathematics
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On the reconstruction of discontinuous functions using multiquadric RBF–WENO local interpolation techniques

2020

Abstract We discuss several approaches involving the reconstruction of discontinuous one-dimensional functions using parameter-dependent multiquadric radial basis function (MQ-RBF) local interpolants combined with weighted essentially non-oscillatory (WENO) techniques, both in the computation of the locally optimized shape parameter and in the combination of RBF interpolants. We examine the accuracy of the proposed reconstruction techniques in smooth regions and their ability to avoid Gibbs phenomena close to discontinuities. In this paper, we propose a true MQ-RBF–WENO method that does not revert to the classical polynomial WENO approximation near discontinuities, as opposed to what was pr…

Numerical AnalysisPolynomialLocal multiquadric radial basis function (RBF) interpolationAdaptive parameterGeneral Computer ScienceApplied MathematicsComputationJump discontinuityClassification of discontinuitiesShape parameterTheoretical Computer ScienceApproximation orderGibbs phenomenonMAT/08 - ANALISI NUMERICAsymbols.namesakeWeighted Essentially Non-Oscillatory (WENO) interpolationModeling and SimulationsymbolsApplied mathematicsRadial basis functionMathematicsInterpolation
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On Ekeland's variational principle in partial metric spaces

2015

In this paper, lower semi-continuous functions are used to extend Ekeland's variational principle to the class of parti al metric spaces. As consequences of our results, we obtain some fixed p oint theorems of Caristi and Clarke types.

Numerical AnalysisPure mathematicsClass (set theory)Applied MathematicsMathematical analysisFixed-point theoremEkeland's variational principleComputer Science ApplicationsMetric spaceComputational Theory and MathematicsVariational principleSettore MAT/05 - Analisi MatematicaEkeland's principle fixed point theory lower-semi continuity partial metric space.AnalysisMathematics
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