Search results for "Local analysis"

showing 10 items of 14 documents

Fourier integral operators and inhomogeneous Gevrey classes

1988

Fourier integral operators with inhomogeneous amplitude and phase junction are studied in the frame of Gevrey classes. Applications are given to propagation of singularities for a pseudodifferential equation.

AmplitudeApplied MathematicsMathematical analysisFrame (networking)Mathematics::Analysis of PDEsMicrolocal analysisPhase (waves)Gravitational singularityMathematics::Spectral TheoryOscillatory integral operatorFourier integral operatorMathematicsAnnali di Matematica Pura ed Applicata
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Determining a Random Schrödinger Operator : Both Potential and Source are Random

2020

We study an inverse scattering problem associated with a Schr\"odinger system where both the potential and source terms are random and unknown. The well-posedness of the forward scattering problem is first established in a proper sense. We then derive two unique recovery results in determining the rough strengths of the random source and the random potential, by using the corresponding far-field data. The first recovery result shows that a single realization of the passive scattering measurements uniquely recovers the rough strength of the random source. The second one shows that, by a single realization of the backscattering data, the rough strength of the random potential can be recovered…

Complex systemMicrolocal analysis01 natural sciencesinversio-ongelmatsähkömagneettinen säteilysymbols.namesakeOperator (computer programming)Mathematics - Analysis of PDEs0103 physical sciencessironta0101 mathematicsMathematical PhysicsMathematics35Q60 35J05 31B10 35R30 78A40osittaisdifferentiaaliyhtälötScattering010102 general mathematicsMathematical analysisErgodicityStatistical and Nonlinear PhysicsInverse scattering problemsymbols010307 mathematical physicsmatemaattiset mallitRealization (probability)Schrödinger's cat
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Existence of fixed points for the sum of two operators

2010

The purpose of this paper is to study the existence of fixed points for the sum of two nonlinear operators in the framework of real Banach spaces. Later on, we give some examples of applications of this type of results (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Discrete mathematicsGeneral MathematicsMicrolocal analysisBanach spaceDissipative operatorFixed pointOperator theoryType (model theory)Integral equationFourier integral operatorMathematicsMathematische Nachrichten
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Territorial Capital and Growth over the Great Recession: a Local Analysis for Italy"

2017

The consequences of the crisis have been mainly analyzed at national/ international levels, neglecting its differential effects on local areas. Notwithstanding the international character of the Great Recession, the different local structural features might have influenced the economic and social impact of the crisis, determining effects on the resilience and recovery chance. In this paper, we focus on the role of different territorial indicators by looking at how their relevance has changed during the recent crisis at provincial level. Our aim is threefold. First, we identify the strategic territorial elements which might be particularly relevant in ensuring a greater local absorption capa…

Economies of agglomerationmedia_common.quotation_subject05 social sciencesControl (management)0211 other engineering and technologiesGeneral Social Sciences021107 urban & regional planning02 engineering and technologySettore SECS-P/06 - Economia ApplicataGreat recessionVariable (computer science)Panel analysisLocal analysisCapital (economics)0502 economics and businessEconomicsTerritorial capital Crisis NUTS-3 regionsEconomic geographyPsychological resilience050207 economicsEconomic systemGeneral Environmental Sciencemedia_common
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Local analysis of the mechanical behaviour of inclusions-containing stainless steels under straining conditions

2003

Abstract A numerical method is described for determining the surface stress distribution under straining conditions from the real microstructure of materials containing local heterogeneities. The method is applied to resulfurized steels with a high density of MnS and oxide inclusions. The results are compared to those obtained from surface observations.

Materials scienceMechanical EngineeringSurface stressNumerical analysisMetallurgyMetals and AlloysOxideCondensed Matter PhysicsMicrostructurechemistry.chemical_compoundchemistryLocal analysisMechanics of MaterialsGeneral Materials ScienceScripta Materialia
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Reflection and Refraction of Singularities for Wave Equations with Interface Conditions given by Fourier Integral Operators

1992

Cauchy problems for hyperbolic operators often have the property, that the singularities of the initial data propagate along the bicharacteristic strips of the operator (cf. e.g. [13]). We consider, in the linear case, the situation where the bicharacteristics hit transversally a spacelike interface, which is ‘active’ in the sense that the interface condition is given via certain Fourier integral operators. Taking the identity, we obtain classical transmission conditions. A suitable functional analytic setting is furnished by the interaction concept [3], [6], [7], which covers very general mutual influences of evolution phenomena on different domains.

Operator (computer programming)Mathematical analysisRefraction (sound)Reflection (physics)Microlocal analysisCauchy distributionGravitational singularityWave equationFourier integral operatorMathematics
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Towards a quantitative comparison between global and local stability analysis

2017

A methodology is proposed here to estimate the stability characteristics of bluff-body wakes using local analysis under the assumption of weakly non-parallel flows. In this connection, a generalisation of the classic spatio-temporal stability analysis for fully three-dimensional flows is first described. Secondly, an additional higher-order correction term with respect to the common saddle-point global frequency estimation is included in the analysis. The proposed method is first validated for the case of the flow past a circular cylinder and then applied to two fully three-dimensional flows: the boundary layer flow over a wall-mounted hemispherical body and the wake flow past a fixed spher…

PhysicsMechanical Engineeringabsolute/convective instabilityMechanicsinstability; Key words absolute/convective instability; wakes; Condensed Matter Physics; Mechanics of Materials; Mechanical EngineeringKey words absolute/convective instabilityCondensed Matter Physics01 natural sciencesStability (probability)Instabilitywakes010305 fluids & plasmasTerm (time)Boundary layerinstabilityFlow (mathematics)Local analysisMechanics of Materials0103 physical sciencesApplied mathematics010306 general physicsabsolute/convective instability; instability; wakesEigenvalues and eigenvectorsSaddle
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Two Minicourses on Analytic Microlocal Analysis

2018

These notes correspond roughly to the two minicourses prepared by the authors for the workshop on Analytic Microlocal Analysis, held at Northwestern University in May 2013. The first part of the text gives an elementary introduction to some global aspects of the theory of metaplectic FBI transforms, while the second part develops the general techniques of the analytic microlocal analysis in exponentially weighted spaces of holomorphic functions.

Pure mathematics010102 general mathematics0103 physical sciencesMicrolocal analysisHolomorphic function0101 mathematics010306 general physics01 natural sciencesMathematics
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Analytic Bergman operators in the semiclassical limit

2018

Transposing the Berezin quantization into the setting of analytic microlocal analysis, we construct approximate semiclassical Bergman projections on weighted $L^2$ spaces with analytic weights, and show that their kernel functions admit an asymptotic expansion in the class of analytic symbols. As a corollary, we obtain new estimates for asymptotic expansions of the Bergman kernel on $\mathbb{C}^n$ and for high powers of ample holomorphic line bundles over compact complex manifolds.

Pure mathematicsadjoint operatorsMicrolocal analysis32A2501 natural sciences[MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph]Limit (mathematics)Bergman projectionComplex Variables (math.CV)[MATH]Mathematics [math]Mathematics::Symplectic GeometryMathematical PhysicsBergman kernelMathematicsasymptotic expansionweighted L2-estimates58J40[MATH.MATH-CV]Mathematics [math]/Complex Variables [math.CV]Mathematical Physics (math-ph)16. Peace & justiceFunctional Analysis (math.FA)Mathematics - Functional Analysisasymptoticstheoremkernelanalytic pseudodifferential operator010307 mathematical physicsAsymptotic expansion47B35classical limitAnalysis of PDEs (math.AP)Toeplitz operatorGeneral Mathematics70H15Holomorphic functionFOS: Physical sciencesSemiclassical physicsKähler manifold[MATH.MATH-FA]Mathematics [math]/Functional Analysis [math.FA]analytic symbolsMathematics - Analysis of PDEskahler-metrics0103 physical sciencesFOS: Mathematics[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]0101 mathematicsMathematics - Complex VariablesMathematics::Complex Variables010102 general mathematics32W25space35A27Kähler manifoldmicrolocal analysisToeplitz operatorquantizationsemiclassical analysis
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A penalty-based interface technology

2009

Modern computers have enabled engineers to perform large scale analyses of complex structures like entire aircrafts, automobiles, and ships. One issue that arises often is the need to perform a unified analysis of a structural assembly using sub-structural models created independently. These sub-structural models are frequently designed by different engineers, thus they are likely to be incompatible at their interfaces. Finite element interface technology has been developed to facilitate the joining of independently modeled substructures. Here an effective and robust interface element is presented. This method has been developed using penalty constraints and allows computationally efficient…

Settore ING-IND/14 - Progettazione Meccanica E Costruzione Di MacchineFinite Element Interface Element Penalty Method Lagrange Multiplier Global/Local Analysis Substructure Composite materials Delamination Mixed-mode propagation.
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