Search results for "boundary value problems"

showing 6 items of 16 documents

Stability of the Calderón problem in admissible geometries

2014

In this paper we prove log log type stability estimates for inverse boundary value problems on admissible Riemannian manifolds of dimension n ≥ 3. The stability estimates correspond to the uniqueness results in [13]. These inverse problems arise naturally when studying the anisotropic Calderon problem. peerReviewed

Pure mathematicsCalderón problemControl and Optimizationta111Stability (learning theory)InversestabilityInverse problemType (model theory)Dimension (vector space)Log-log plotModeling and SimulationInverse boundary value problemsDiscrete Mathematics and CombinatoricsPharmacology (medical)UniquenessBoundary value problemAnalysisMathematicsInverse Problems & Imaging
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Morse-Smale index theorems for elliptic boundary deformation problems.

2012

AbstractMorse-type index theorems for self-adjoint elliptic second order boundary value problems arise as the second variation of an energy functional corresponding to some variational problem. The celebrated Morse index theorem establishes a precise relation between the Morse index of a geodesic (as critical point of the geodesic action functional) and the number of conjugate points along the curve. Generalization of this theorem to linear elliptic boundary value problems appeared since seventies. (See, for instance, Smale (1965) [12], Uhlenbeck (1973) [15] and Simons (1968) [11] among others.) The aim of this paper is to prove a Morse–Smale index theorem for a second order self-adjoint el…

Pure mathematicsGeodesicApplied MathematicsMathematical analysisMixed boundary conditionSpectral flow Maslov index Index Theory Elliptic boundary value problemsElliptic boundary value problemsElliptic boundary value problemElliptic boundary deformation problemMaslov indexNeumann boundary conditionFree boundary problemSpectral flowElliptic boundary deformation problemsIndex TheoryBoundary value problemAtiyah–Singer index theoremAnalysisEnergy functionalMathematics
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Green’s function and existence of solutions for a third-order three-point boundary value problem

2019

The solutions of third-order three-point boundary value problem x‘‘‘ + f(t, x) = 0, t ∈ [a, b], x(a) = x‘(a) = 0, x(b) = kx(η), where η ∈ (a, b), k ∈ R, f ∈ C([a, b] × R, R) and f(t, 0) ≠ 0, are the subject of this investigation. In order to establish existence and uniqueness results for the solutions, attention is focused on applications of the corresponding Green’s function. As an application, also one example is given to illustrate the result. Keywords: Green’s function, nonlinear boundary value problems, three-point boundary conditions, existence and uniqueness of solutions.

Pure mathematicsthree-point boundary conditionsValue (computer science)010103 numerical & computational mathematicsFunction (mathematics)Green’s function01 natural sciences010101 applied mathematicsThird ordersymbols.namesakeexistence and uniqueness of solutionsModeling and SimulationGreen's functionsymbolsQA1-939nonlinear boundary value problemsOrder (group theory)Nonlinear boundary value problemBoundary value problemUniqueness0101 mathematicsAnalysisMathematicsMathematicsMathematical Modelling and Analysis
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Existence of a unique solution for a third-order boundary value problem with nonlocal conditions of integral type

2021

The existence of a unique solution for a third-order boundary value problem with integral condition is proved in several ways. The main tools in the proofs are the Banach fixed point theorem and the Rus’s fixed point theorem. To compare the applicability of the obtained results, some examples are considered.

QA299.6-433Pure mathematicsintegral boundary conditionsBanach fixed point theoremBanach fixed-point theoremApplied MathematicsFixed-point theoremthird-order nonlinear boundary value problemsGreen’s functionType (model theory)Mathematical proofRus’s fixed point theoremThird ordersymbols.namesakeexistence and uniqueness of solutionsGreen's functionsymbolsBoundary value problemAnalysisMathematicsNonlinear Analysis: Modelling and Control
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Estimates of the modeling error generated by homogenization of an elliptic boundary value problem

2016

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch)

posteriori error estimateshomogenizationmodeling error010103 numerical & computational mathematics01 natural sciencesHomogenization (chemistry)Elliptic boundary value problem510 Mathematicselliptic boundary value problemsBoundary value problemNumerical testsperiodic structures0101 mathematicsMathematicsHomogenization510: Mathematik010102 general mathematicsMathematical analysisElliptic boundary value problemPeriodic structureModeling error10123 Institute of MathematicsComputational MathematicsExact solutions in general relativityRate of convergenceNorm (mathematics)A priori and a posteriori2605 Computational MathematicsA posteriori error estimateJournal of Numerical Mathematics
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Generalized wave propagation problems and discrete exterior calculus

2018

We introduce a general class of second-order boundary value problems unifying application areas such as acoustics, electromagnetism, elastodynamics, quantum mechanics, and so on, into a single framework. This also enables us to solve wave propagation problems very efficiently with a single software system. The solution method precisely follows the conservation laws in finite-dimensional systems, whereas the constitutive relations are imposed approximately. We employ discrete exterior calculus for the spatial discretization, use natural crystal structures for three-dimensional meshing, and derive a “discrete Hodge” adapted to harmonic wave. The numerical experiments indicate that the cumulat…

raja-arvotHelmholtz equationDiscretizationWave propagationboundary value problemssähkömagnetismielectromagnetism010103 numerical & computational mathematics02 engineering and technologyalgebra01 natural sciencesdiscrete exterior calculusdifferentiaaligeometriaakustiikka0202 electrical engineering electronic engineering information engineeringApplied mathematicsBoundary value problemkvanttimekaniikkadifferential geometry0101 mathematicsacousticsMathematicsta113Numerical AnalysisConservation lawfinite differenceApplied MathematicsFinite difference020206 networking & telecommunicationsFinite element methodComputational MathematicsDiscrete exterior calculusModeling and SimulationelasticityAnalysisexterior algebra
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