Search results for " Regularity"

showing 10 items of 67 documents

Corners in non-equiregular sub-Riemannian manifolds

2014

We prove that in a class of non-equiregular sub-Riemannian manifolds corners are not length minimizing. This extends the results of (G.P. Leonardi and R. Monti, Geom. Funct. Anal. 18 (2008) 552-582). As an application of our main result we complete and simplify the analysis in (R. Monti, Ann. Mat. Pura Appl. (2013)), showing that in a 4-dimensional sub-Riemannian structure suggested by Agrachev and Gauthier all length-minimizing curves are smooth. Mathematics Subject Classification. 53C17, 49K21, 49J15.

Mathematics - Differential GeometryPure mathematicsClass (set theory)Control and Optimizationregularity of geodesicsStructure (category theory)Mathematics - Analysis of PDEsMathematics - Metric GeometryFOS: MathematicsGEOMSub-Riemannian geometry regularity of geodesics cornersMathematics - Optimization and ControlMathematicsta111Computational mathematicsMetric Geometry (math.MG)cornerssub-riemannian geometryComputational MathematicsCorners; Regularity of geodesics; Sub-Riemannian geometry; Control and Systems Engineering; Control and Optimization; Computational MathematicsDifferential Geometry (math.DG)Mathematics Subject ClassificationOptimization and Control (math.OC)Control and Systems EngineeringMathematics::Differential GeometryAnalysis of PDEs (math.AP)
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Superlinear (p(z), q(z))-equations

2017

AbstractWe consider Dirichlet boundary value problems for equations involving the (p(z), q(z))-Laplacian operator in the principal part and prove the existence of one and three nontrivial weak solutions, respectively. Here, the nonlinearity in the reaction term is allowed to depend on the solution, but does not satisfy the Ambrosetti–Rabinowitz condition. The hypotheses on the reaction term ensure that the Euler–Lagrange functional, associated to the problem, satisfies both the -condition and a mountain pass geometry.

Mathematics::Analysis of PDEs01 natural sciencesDirichlet distributionsymbols.namesakeSettore MAT/05 - Analisi MatematicaBoundary value problemMountain pass0101 mathematicsMathematicsNumerical Analysisgeographygeography.geographical_feature_category (p(z)q(z))-Laplacian operatorApplied MathematicsWeak solutionOperator (physics)010102 general mathematicsMathematical analysisweak solutionTerm (time)010101 applied mathematicsComputational MathematicsNonlinear system(Cc)-condition(p(z)critical groupsymbolsnonlinear regularityPrincipal partAnalysisComplex Variables and Elliptic Equations
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Regularity of some method of summation for double sequences

2010

Some generalization of Toeplitz method of summation is introduced for double sequences and condition of regularity of it is obtained.

Mathematics::Functional AnalysisMathematics::Operator AlgebrasToeplitz method of summationlcsh:MathematicsDouble sequenceslcsh:QA1-939Method of summationConditions of regularity.Le Matematiche
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Nonlinear Robin problems with unilateral constraints and dependence on the gradient

2018

We consider a nonlinear Robin problem driven by the p-Laplacian, with unilateral constraints and a reaction term depending also on the gradient (convection term). Using a topological approach based on fixed point theory (the Leray-Schauder alternative principle) and approximating the original problem using the Moreau-Yosida approximations of the subdifferential term, we prove the existence of a smooth solution.

Mathematics::Functional Analysisfixed pointSettore MAT/05 - Analisi Matematicalcsh:Mathematicsp-LaplacianMathematics::Analysis of PDEsnonlinear regularityconvection termRobin boundary conditionlcsh:QA1-939maximal monotone mapsubdifferential termElectronic Journal of Differential Equations
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Positive solutions for parametric singular Dirichlet (p,q)-equations

2020

We consider a nonlinear elliptic Dirichlet problem driven by the (p,q)-Laplacian and a reaction consisting of a parametric singular term plus a Caratheodory perturbation f(z,x) which is (p-1)-linear as x goes to + infinity. First we prove a bifurcation-type theorem describing in an exact way the changes in the set of positive solutions as the parameter lambda>0 moves. Subsequently, we focus on the solution multifunction and prove its continuity properties. Finally we prove the existence of a smallest (minimal) solution u*_lambda and investigate the monotonicity and continuity properties of the map lambda --> u*_lambda.

Minimal solutionSettore MAT/05 - Analisi MatematicaNonlinear maximum principleBifurcation-type theoremSolution multifunctionNonlinear regularity
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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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Approximation of plurisubharmonic functions

2015

We extend a result by Fornaaess and Wiegerinck [Ark. Mat. 1989;27:257-272] on plurisubharmonic Mergelyan type approximation to domains with boundaries locally given by graphs of continuous functions.

Numerical AnalysisPure mathematicsApplied Mathematics010102 general mathematicsMathematical analysista111Type (model theory)01 natural sciences010101 applied mathematicsComputational Mathematicsboundary regularityMergelyan type approximationcontinuous boundaryplurisubharmonic functions0101 mathematicsapproximationAnalysisMathematicsComplex Variables and Elliptic Equations
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Nonlinear concave-convex problems with indefinite weight

2021

We consider a parametric nonlinear Robin problem driven by the p-Laplacian and with a reaction having the competing effects of two terms. One is a parametric (Formula presented.) -sublinear term (concave nonlinearity) and the other is a (Formula presented.) -superlinear term (convex nonlinearity). We assume that the weight of the concave term is indefinite (that is, sign-changing). Using the Nehari method, we show that for all small values of the parameter (Formula presented.), the problem has at least two positive solutions and also we provide information about their regularity.

Numerical AnalysisPure mathematicslocal minimizerspositive solutionsNehari manifoldApplied MathematicsRegular polygonLagrange multiplierComputational MathematicsNonlinear systemSettore MAT/05 - Analisi Matematicanonlinear regularityAnalysisMathematics
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The Wage Curve, Once More with Feeling: Bayesian Model Averaging of Heckit Models

2018

The sensitivity of the wage curve to sample-selection and model uncertainty was evaluated with Bayesian methods. More than 8000 Heckit wage curves were estimated using data from the 2017 household survey of Bolivia. After averaging the estimates with the posterior probability of each model being true, the wage curve elasticity in Bolivia is close to -0.01. This result suggests that in this country the wage curve is inelastic and does not follow the international statistical regularity of wage curves. 

Physics::Physics and SocietyStatistical regularityWage curveStatistics::Applicationsmedia_common.quotation_subjectBayesian probabilityPosterior probabilityMathematics::History and OverviewWageBayesian inferenceComputer Science::Computers and SocietyHousehold surveylcsh:Financelcsh:HG1-9999EconometricsMathematicsmedia_common
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A singular (p,q)-equation with convection and a locally defined perturbation

2021

We consider a parametric Dirichlet problem driven by the (p,q)-Laplacian and a reaction which is gradient dependent (convection) and the competing effects of two more terms, one a parametric singular term and a locally defined perturbation. We show that for all small values of the parameter the problem has a positive smooth solution.

Positive solutionPseudomonotone operatorSettore MAT/05 - Analisi MatematicaSettore MAT/03 - GeometriaNonlinear maximum principleConvectionNonlinear regularity
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