Search results for "Inverse"

showing 10 items of 630 documents

Increasing stability in the linearized inverse Schrödinger potential problem with power type nonlinearities

2022

We consider increasing stability in the inverse Schr\"{o}dinger potential problem with power type nonlinearities at a large wavenumber. Two linearization approaches, with respect to small boundary data and small potential function, are proposed and their performance on the inverse Schr\"{o}dinger potential problem is investigated. It can be observed that higher order linearization for small boundary data can provide an increasing stability for an arbitrary power type nonlinearity term if the wavenumber is chosen large. Meanwhile, linearization with respect to the potential function leads to increasing stability for a quadratic nonlinearity term, which highlights the advantage of nonlinearit…

osittaisdifferentiaaliyhtälötincreasing stabilityreconstruction algorithmsApplied Mathematicspower type nonlinearitiesinversio-ongelmatComputer Science ApplicationsTheoretical Computer ScienceMathematics - Analysis of PDEsSignal ProcessingFOS: Mathematicsinverse Schrödinger potential problemMathematical PhysicsAnalysis of PDEs (math.AP)
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On some partial data Calderón type problems with mixed boundary conditions

2021

In this article we consider the simultaneous recovery of bulk and boundary potentials in (degenerate) elliptic equations modelling (degenerate) conducting media with inaccessible boundaries. This connects local and nonlocal Calderón type problems. We prove two main results on these type of problems: On the one hand, we derive simultaneous bulk and boundary Runge approximation results. Building on these, we deduce uniqueness for localized bulk and boundary potentials. On the other hand, we construct a family of CGO solutions associated with the corresponding equations. These allow us to deduce uniqueness results for arbitrary bounded, not necessarily localized bulk and boundary potentials. T…

osittaisdifferentiaaliyhtälötinverse problemsApplied Mathematics(fractional) Calderón problem010102 general mathematicsDegenerate energy levelsMathematical analysisBoundary (topology)Duality (optimization)Type (model theory)partial dataCarleman estimates01 natural sciencesinversio-ongelmatrunge approximationcomplex geometrical optics solutions010101 applied mathematicsBounded functionBoundary value problemUniqueness0101 mathematicsapproksimointiAnalysisMathematicsestimointiJournal of Differential Equations
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Partial Data Problems and Unique Continuation in Scalar and Vector Field Tomography

2022

AbstractWe prove that if P(D) is some constant coefficient partial differential operator and f is a scalar field such that P(D)f vanishes in a given open set, then the integrals of f over all lines intersecting that open set determine the scalar field uniquely everywhere. This is done by proving a unique continuation property of fractional Laplacians which implies uniqueness for the partial data problem. We also apply our results to partial data problems of vector fields.

osittaisdifferentiaaliyhtälötvector field tomographyinverse problemstomografiaApplied MathematicsGeneral MathematicsX-ray tomographyregion of interest tomographyunique continuationinversio-ongelmatAnalysisJournal of Fourier Analysis and Applications
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Dziecko w roli rodzica – pomylone role rodzinne. O parentyfikacji w doniesieniach światowych i polskich

2018

Cel. Celem artykułu, o charakterze przeglądowym, jest wyjaśnienie zjawiska parentyfikacji, jej uwarunkowań i konsekwencji z nią związanych. Parentyfikacja najczęściej określana jest jako odwrócona rola w rodzinie i dotyczy zamiany roli między rodzicem a dzieckiem. Dochodzi do niej wówczas gdy rodzic, częściowo lub całkowicie rezygnuje ze swoich zadań i obowiązków rodzicielskich. Abdykacja rodzica uruchamia proces parentyfikacji, w którym zwykle jedno, najczęściej najstarsze dziecko w rodzinie, czuje się oddelegowane do przejęcia roli rodzicielskiej, w różnych sferach życia rodzinnego. Świadoma pomoc i obowiązki mogą mieć charakter instrumentalny lub emocjonalny. Dziecko poddane procesowi pa…

parentyfikacjaodwrócona rola rodzicielskainversed parenting rolerole inversionmylenie rólinwersja roli Abstractparentificationrole confusionWychowanie w rodzinie
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"Table 2" of "First study of the two-body scattering involving charm hadrons"

2022

$1\sigma$ confidence interval for the $\mathrm{N\overline{D}}$ inverse scattering length for the isospin $\mathrm{I}=0$ channel, $f_{0,~\mathrm{I}=0}^{-1}$, as a function of the effective source radius $R_\mathrm{eff}$.

pp --> \mathrm{pD^-}(\mathrm{\overline{p}D^+}) + Xinverse scattering length13000
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"Table 3" of "First study of the two-body scattering involving charm hadrons"

2022

Best fit for the $\mathrm{N\overline{D}}$ inverse scattering length for the isospin $\mathrm{I}=0$ channel, $f_{0,~\mathrm{I}=0}^{-1}$, as a function of the effective source radius $R_\mathrm{eff}$.

pp --> \mathrm{pD^-}(\mathrm{\overline{p}D^+}) + Xinverse scattering length13000
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The Abelian Kernel of an Inverse Semigroup

2020

The problem of computing the abelian kernel of a finite semigroup was first solved by Delgado describing an algorithm that decides whether a given element of a finite semigroup S belongs to the abelian kernel. Steinberg extended the result for any variety of abelian groups with decidable membership. In this paper, we used a completely different approach to complete these results by giving an exact description of the abelian kernel of an inverse semigroup. An abelian group that gives this abelian kernel was also constructed.

profinite topologiesPure mathematicsabelian kernelsSemigroupGeneral Mathematicslcsh:Mathematics010102 general mathematicsfinite semigroup010103 numerical & computational mathematicslcsh:QA1-93901 natural sciencesDecidabilityextension problemKernel (algebra)Inverse semigroupComputer Science (miscellaneous)0101 mathematicsAbelian groupVariety (universal algebra)Element (category theory)partial automorphismsEngineering (miscellaneous)MathematicsMathematics
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Applications of Microlocal Analysis in Inverse Problems

2020

This note reviews certain classical applications of microlocal analysis in inverse problems. The text is based on lecture notes for a postgraduate level minicourse on applications of microlocal analysis in inverse problems, given in Helsinki and Shanghai in June 2019.

radon transformRadon transforminverse problemsGeneral Mathematicslcsh:Mathematics010102 general mathematicscalderón problemMicrolocal analysisDirichlet-to-Neumann mapInverse problemlcsh:QA1-93901 natural sciencesinversio-ongelmatGel’fand problem010104 statistics & probabilitymicrolocal analysisComputer Science (miscellaneous)Calculus0101 mathematicsPostgraduate levelEngineering (miscellaneous)MathematicsMathematics
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Mappings of L p -integrable distortion: regularity of the inverse

2016

Let X be an open set in R n and suppose that f : X → R n is a Sobolev homeomorphism. We study the regularity of f −1 under the L p -integrability assumption on the distortion function Kf . First, if X is the unit ball and p > n−1, then the optimal local modulus of continuity of f −1 is attained by a radially symmetric mapping. We show that this is not the case when p 6 n − 1 and n > 3, and answer a question raised by S. Hencl and P. Koskela. Second, we obtain the optimal integrability results for |Df −1 | in terms of the L p -integrability assumptions of Kf . peerReviewed

regularity of the inverseSobolev homeomorphismmappings of finite distortionmodulus of continuityhigher integrability
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Mappings of Lp-integrable distortion: regularity of the inverse

2016

Let be an open set in ℝn and suppose that is a Sobolev homeomorphism. We study the regularity of f–1 under the Lp-integrability assumption on the distortion function Kf. First, if is the unit ball and p > n – 1, then the optimal local modulus of continuity of f–1 is attained by a radially symmetric mapping. We show that this is not the case when p ⩽ n – 1 and n ⩾ 3, and answer a question raised by S. Hencl and P. Koskela. Second, we obtain the optimal integrability results for ∣Df–1∣ in terms of the Lp-integrability assumptions of Kf.

regularity of the inverseUnit sphereDistortion functionDiscrete mathematicsPure mathematicsSobolev homeomorphismGeneral Mathematicsta111010102 general mathematicsOpen setInverse01 natural sciencesModulus of continuityHomeomorphism010101 applied mathematicsSobolev spaceDistortion (mathematics)mappings of finite distortionmodulus of continuityhigher integrability0101 mathematicsMathematicsProceedings of the Royal Society of Edinburgh: Section A Mathematics
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