Search results for "Boundary value problems"

showing 10 items of 16 documents

On the solution of a parabolic PDE involving a gas flow through a semi-infinite porous medium

2021

Abstract Taking as start point the parabolic partial differential equation with the respective initial and boundary conditions, the present research focuses onto the flow of a sample of waste-water derived from a standard/conventional dyeing process. In terms of a highly prioritized concern, meaning environment decontamination and protection, in order to remove the dyes from the waste waters, photocatalyses like ZnO or TiO2 nanoparticles were formulated, due to their high surface energy which makes them extremely reactive and attractive. According to the basics of ideal fluid, the key point is the gas flow through an ideal porous pipe consisting of nanoparticles bound one to each other, for…

010302 applied physicsPartial differential equationDifferential equationNumerical analysisGeneral Physics and Astronomy02 engineering and technologyMechanicsWastewater decontamination021001 nanoscience & nanotechnology01 natural sciencesParabolic partial differential equationlcsh:QC1-999Parabolic equation and systemsBoundary value problemsDifferential equationFlow (mathematics)0103 physical sciencesNanoporous ZnO particlesBoundary value problem0210 nano-technologyPorosityPorous mediumlcsh:PhysicsNumerical analysisResults in Physics
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A geometrical criterion for nonexistence of constant-sign solutions for some third-order two-point boundary value problems

2020

We give a simple geometrical criterion for the nonexistence of constant-sign solutions for a certain type of third-order two-point boundary value problem in terms of the behavior of nonlinearity in the equation. We also provide examples to illustrate the applicability of our results.

Applied MathematicsMathematical analysislcsh:QA299.6-433lcsh:AnalysisType (model theory)nonexistence of solutionsthird-order two-point boundary value problemsNonlinear systemThird orderSimple (abstract algebra)comparison methods for the first zero functionsBoundary value problemConstant (mathematics)Value (mathematics)AnalysisMathematicsSign (mathematics)Nonlinear Analysis
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Multiple solutions for a Sturm-Liouville problem with mixed boundary conditions

2010

Critical points mixed boundary value problems multiple solutions
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Positive solutions for a discrete two point nonlinear boundary value problem with p-Laplacian

2017

Abstract In the framework of variational methods, we use a two non-zero critical points theorem to obtain the existence of two positive solutions to Dirichlet boundary value problems for difference equations involving the discrete p -Laplacian operator.

Difference equationDiscrete boundary value problemTwo solution01 natural sciencesElliptic boundary value problemDirichlet distributionCritical point theory; Difference equations; Discrete boundary value problems; p-Laplacian; Positive solutions; Two solutions; Analysis; Applied MathematicsPositive solutionsymbols.namesakePoint (geometry)Boundary value problem0101 mathematicsMathematicsApplied Mathematics010102 general mathematicsMathematical analysisp-LaplacianAnalysiMixed boundary condition010101 applied mathematicssymbolsp-LaplacianCritical point theoryNonlinear boundary value problemLaplace operatorAnalysis
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Guaranteed error bounds for a class of Picard-Lindelöf iteration methods

2013

We present a new version of the Picard-Lindelof method for ordinary dif- ¨ ferential equations (ODEs) supplied with guaranteed and explicitly computable upper bounds of an approximation error. The upper bounds are based on the Ostrowski estimates and the Banach fixed point theorem for contractive operators. The estimates derived in the paper take into account interpolation and integration errors and, therefore, provide objective information on the accuracy of computed approximations. peerReviewed

Discrete mathematicsClass (set theory)Banach fixed-point theoremOdeguaranteed error boundsPicard-Lindelöf methodsinversio-ongelmatelliptic boundary value problemsPower iterationApproximation errorOrdinary differential equationComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATIONApplied mathematicsa posteriori estimatesObjective informationInterpolationMathematics
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An augmented MFS approach for brain activity reconstruction

2017

Abstract Weak electrical currents in the brain flow as a consequence of acquisition, processing and transmission of information by neurons, giving rise to electric and magnetic fields, which can be modeled by the quasi-stationary approximation of Maxwell’s equations. Electroencephalography (EEG) and magnetoencephalography (MEG) techniques allow for reconstructing the cerebral electrical currents and thus investigating the neuronal activity in the human brain in a non-invasive way. This is a typical electromagnetic inverse problem which can be addressed in two stages. In the first one a physical and geometrical representation of the head is used to find the relation between a given source mo…

Electromagnetic fieldNumerical AnalysisGeneral Computer Sciencemedicine.diagnostic_testApplied MathematicsScalar (physics)010103 numerical & computational mathematicsMagnetoencephalographyInverse problem01 natural sciencesFinite element methodTheoretical Computer Science010101 applied mathematicsSettore MAT/08 - Analisi NumericaSettore ING-IND/31 - ElettrotecnicaMethod of Fundamental Solutions Boundary value problems M/EEG LOOCV algorithmModeling and SimulationmedicineMethod of fundamental solutionsBoundary value problem0101 mathematicsBoundary element methodAlgorithmMathematics
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Infinitely many solutions for a mixed boundary value problem

2010

The existence of infinitely many solutions for a mixed boundary value problem is established. The approach is based on variational methods.

General MathematicsMathematical analysisFree boundary problemBoundary value problemMixed boundary conditionCritical points mixed boundary value problems infinitely many solutionsMathematics
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Sturm'a metodes parasto otrās kārtas diferenciālvienādojumu robežproblēmās: maģistra darbs

1942

Matemātiskā analīzeDifferential equationsBoundary value problemsDiplomdarbi:MATHEMATICS::Algebra geometry and mathematical analysis::Mathematical analysis [Research Subject Categories]DiferenciālvienādojumiRobežproblēmas (diferenciālvienādojumi)
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Nonlocal Third Order Boundary Value Problems with Solutions that Change Sign

2014

We investigate the existence and the number of solutions for a third order boundary value problem with nonlocal boundary conditions in connection with the oscillatory behavior of solutions. The combination of the shooting method and scaling method is used in the proofs of our main results. Examples are included to illustrate the results.

Mathematical analysisestimation of the number of solutionsMixed boundary conditionSingular boundary methodBoundary knot methodRobin boundary conditionnonlocal boundary conditionsBoundary conditions in CFDShooting methodModeling and SimulationQA1-939nonlinear boundary value problemsBoundary value problemMathematicsAnalysisSign (mathematics)MathematicsMathematical Modelling and Analysis
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Fizikas un matemātikas zinātņu doktors Arnolds Lepins: biobibliogrāfiskais rādītājs

1990

Biobibliogrāfiskajā rādītājā ietverti fizikas un matemātikas zinātņu doktora profesora Arnolda Lepina publicētie darbi no 1952.gada līdz 1991.gadam, kā ari uzrādīta literatūra par viņu.

Professors of the Latvian UniversityДифференциальные уравнения - библиографический указатель:MATHEMATICS [Research Subject Categories]Differential equations - bibliographical indexRobežproblēmas (diferenciālvienādojumi) - bibliogrāfiskais rādītājsBiobibliogrāfiskie rādītājiDiferenciālvienādojumi - bibliogrāfiskais rādītājsMatemātiskā fizika - bibliogrāfiskais rādītājsHistory of the University of LatviaMatemātika - bibliogrāfiskais rādītājsLatvijas Universitātes vēstureBoundary value problems (differential equations) - bibliographical indexLatvijas Universitātes profesoriMatemātikas zinātņu profesori Latvijas Univesitātē
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