Search results for "Linear system"

showing 10 items of 1558 documents

Positive solutions of Dirichlet and homoclinic type for a class of singular equations

2018

Abstract We study a nonlinear singular boundary value problem and prove that, depending on a relationship between exponents of power terms, the problem has either solutions of Dirichlet type or homoclinic solutions. We make use of shooting techniques and lower and upper solutions.

Dirichlet problemPure mathematicsClass (set theory)SingularityApplied Mathematics010102 general mathematicsAnalysiType (model theory)01 natural sciencesDirichlet distributionPositive solution010101 applied mathematicssymbols.namesakeNonlinear systemSingularityHomoclinic solutionsymbolsHomoclinic orbitBoundary value problem0101 mathematicsAnalysisDirichlet problemMathematicsJournal of Mathematical Analysis and Applications
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Existence of non-zero solutions for a Dirichlet problem driven by (p(x),q(x)-Laplacian

2021

The paper focuses on a Dirichlet problem driven by the (Formula presented.) -Laplacian. The existence of at least two non-zero solutions under suitable conditions on the nonlinear term is established. The approach is based on variational methods.

Dirichlet problemPure mathematicsmultiple solutionscritical pointsApplied Mathematics010102 general mathematicsZero (complex analysis)q(x))-LaplacianMathematics::Spectral Theory-Laplacian01 natural sciences(p(x)q(x))-Laplacian critical points multiple solutions Dirichlet problemTerm (time)010101 applied mathematicsNonlinear systemSettore MAT/05 - Analisi Matematica0101 mathematics(p(x)Laplace operatorAnalysisDirichlet problemMathematicsApplicable Analysis
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On Noncoercive (p, q)-Equations

2021

We consider a nonlinear Dirichlet problem driven by a (p, q)-Laplace differential operator (1 < q < p). The reaction is (p - 1)-linear near +/-infinity and the problem is noncoercive. Using variational tools and truncation and comparison techniques together with critical groups, we produce five nontrivial smooth solutions all with sign information and ordered. In the particular case when q = 2, we produce a second nodal solution for a total of six nontrivial smooth solutions all with sign information.

Dirichlet problemTruncationGeneral MathematicsMathematical analysisGeneral Physics and AstronomyDifferential operator(pq)-LaplacianNonlinear systemextremal solutionsprincipal eigenvalueSettore MAT/05 - Analisi Matematicanonlinear regularityconstant sign and nodal solutionsSign (mathematics)Mathematics
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Nonlinear Diffusion in Transparent Media

2021

Abstract We consider a prototypical nonlinear parabolic equation whose flux has three distinguished features: it is nonlinear with respect to both the unknown and its gradient, it is homogeneous, and it depends only on the direction of the gradient. For such equation, we obtain existence and uniqueness of entropy solutions to the Dirichlet problem, the homogeneous Neumann problem, and the Cauchy problem. Qualitative properties of solutions, such as finite speed of propagation and the occurrence of waiting-time phenomena, with sharp bounds, are shown. We also discuss the formation of jump discontinuities both at the boundary of the solutions’ support and in the bulk.

Dirichlet problemflux-saturated diffusion equationsGeneral Mathematicsneumann problemMathematical analysisparabolic equationsBoundary (topology)waiting time phenomenaClassification of discontinuitiesparabolic equations; dirichlet problem; cauchy problem; neumann problem; entropy solutions; flux-saturated diffusion equations; waiting time phenomena; conservation lawsNonlinear systemMathematics - Analysis of PDEsFOS: MathematicsNeumann boundary conditionInitial value problemcauchy problemUniquenessdirichlet problemconservation lawsEntropy (arrow of time)entropy solutionsAnalysis of PDEs (math.AP)MathematicsInternational Mathematics Research Notices
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Fixed point theory for 1-set contractive and pseudocontractive mappings

2013

The purpose of this paper is to study the existence and uniqueness of fixed point for a class of nonlinear mappings defined on a real Banach space, which, among others, contains the class of separate contractive mappings, as well as to see that an important class of 1-set contractions and of pseudocontractions falls into this type of nonlinear mappings. As a particular case, we give an iterative method to approach the fixed point of a nonexpansive mapping. Later on, we establish some fixed point results of Krasnoselskii type for the sum of two nonlinear mappings where one of them is either a 1-set contraction or a pseudocontraction and the another one is completely continuous, which extend …

Discrete mathematicsComputational MathematicsNonlinear systemIterative methodApplied MathematicsBanach spaceFixed-point theoremUniquenessFixed pointFixed-point propertyCoincidence pointMathematicsApplied Mathematics and Computation
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When is the Haar measure a Pietsch measure for nonlinear mappings?

2012

We show that, as in the linear case, the normalized Haar measure on a compact topological group $G$ is a Pietsch measure for nonlinear summing mappings on closed translation invariant subspaces of $C(G)$. This answers a question posed to the authors by J. Diestel. We also show that our result applies to several well-studied classes of nonlinear summing mappings. In the final section some problems are proposed.

Discrete mathematicsGeneral MathematicsTranslation (geometry)Linear subspaceMeasure (mathematics)Functional Analysis (math.FA)Section (fiber bundle)Mathematics - Functional AnalysisNonlinear systemFOS: MathematicsTopological groupInvariant (mathematics)MathematicsHaar measure
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Random analysis of geometrically non-linear FE modelled structures under seismic actions

1990

Abstract In the framework of the finite element (FE) method, by using the “total Lagrangian approach”, the stochastic analysis of geometrically non-linear structures subjected to seismic inputs is performed. For this purpose the equations of motion are written with the non-linear contribution in an explicit representation, as pseudo-forces, and with the ground motion modelled as a filtered non-stationary white noise Gaussian process, using a Tajimi-Kanai-like filter. Then equations for the moments of the response are obtained by extending the classical Ito's rule to vectors of random processes. The equations of motion, and the equations for moments, obtained here, show a perfect formal simi…

Discrete mathematicsHermite polynomialsSimilarity (geometry)Random excitation; non-linear structuresStochastic processMathematical analysisEquations of motionBuilding and ConstructionWhite noiseFinite element methodRandom excitationNonlinear systemsymbols.namesakesymbolsnon-linear structuresSafety Risk Reliability and QualityGaussian processCivil and Structural EngineeringMathematics
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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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Summability and estimates for polynomials and multilinear mappings

2008

Abstract In this paper we extend and generalize several known estimates for homogeneous polynomials and multilinear mappings on Banach spaces. Applying the theory of absolutely summing nonlinear mappings, we prove that estimates which are known for mappings on l p spaces in fact hold true for mappings on arbitrary Banach spaces.

Discrete mathematicsMultilinear mapPure mathematicsMathematics::Functional AnalysisMathematics(all)General MathematicsBanach spaceAbsolutely summingNonlinear systemCotypeHomogeneousEstimatesMultilinear mappingsMathematicsIndagationes Mathematicae
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Finite Groups with Only One NonLinear Irreducible Representation

2012

Let 𝕂 be an algebraically closed field. We classify the finite groups having exactly one irreducible 𝕂-representation of degree bigger than one. The case where the characteristic of 𝕂 is zero, was done by G. Seitz in 1968.

Discrete mathematicsNonlinear systemAlgebra and Number TheoryDegree (graph theory)Irreducible representationZero (complex analysis)Algebraically closed fieldMathematicsCommunications in Algebra
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