Search results for "Regular"

showing 10 items of 855 documents

Optimization and Inversion

2009

Tikhonov regularizationComputer scienceGeophysicsDensity contrastInversion (discrete mathematics)Bouguer anomaly
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Validation of the solution method using Tikhonov regularization algorithm for spectral line diagnostics of microsize plasma

2014

This paper is devoted obtaining the threshold of the credibility of the solution by means of Tikhonov's regularization method in case of spectral lines, emitted from microsize plasma sources. The reliability of Tikhonov algorithm was verified by means of solving model tasks with different ratio between instrumental function and measured profile and, with different levels of noise.

Tikhonov regularizationInstrumental functionPlasmaRegularization (mathematics)AlgorithmSpectral lineMathematicsSPIE Proceedings
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Regularization Method in Infrared Image Processing

2003

Abstract Infrared images often present distortions induced by the measurement system. Thus, image processing is a vital part of infrared measurements. A distortion model based on a convolution product is presented. Image restoration is an ill-posed problem and its solution can be obtained using regularization methods. In this paper, image restoration is performed using a variation of Tikhonov regularization that makes use of the particular form of the convolution kernel matrix, which is built as a block-circulant matrix that admits a diagonal form in the two-dimensional Fourier space. The restoration procedure is used to restore a knife-edge infrared source image.

Tikhonov regularizationKernel (image processing)Diagonal formbusiness.industrySystem of measurementFrequency domainImage processingComputer visionArtificial intelligencebusinessRegularization (mathematics)Image restorationMathematicsIFAC Proceedings Volumes
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New Regularization Method for EXAFS Analysis

2007

As an alternative to the analysis of EXAFS spectra by conventional shell fitting, the Tikhonov regularization method has been proposed. An improved algorithm that utilizes a priori information about the sample has been developed and applied to the analysis of U L3‐edge spectra of soddyite, (UO2)2SiO4⋅2H2O, and of U(VI) sorbed onto kaolinite. The partial radial distribution functions g1(UU), g2(USi), and g3(UO) of soddyite agree with crystallographic values and previous EXAFS results.

Tikhonov regularizationX-ray spectroscopyExtended X-ray absorption fine structureAbsorption spectroscopyChemistryRegularization (physics)Analytical chemistryCrystal structureSpectroscopySpectral lineAIP Conference Proceedings
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Deconvolution of Multiple Spectral Lines Shapes by Means of Tikhonov’s Regularization Method

2013

We present deconvolution of multiple narrow Zeeman split Hg lines, emitted from Hg/Xe micro-size capillary and measured by the Fourier Transform spectrometer. The ill-posed inverse problem was solved using the Tikhonov& rsquo;s regularization method.

Tikhonov regularizationsymbols.namesakeZeeman effectFourier transform spectrometersAnalytical chemistrysymbolsDeconvolutionInverse problemRegularization (mathematics)Spectral lineMathematicsMagnetic fieldComputational physicsImaging and Applied Optics
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Measurement of t ¯ t production with a veto on additional central jet activity in pp collisions at √ s = 7 TeV using the ATLAS detector

2012

A measurement of the jet activity in t[bar over t] events produced in proton–proton collisions at a centre-of-mass energy of 7 TeV is presented, using 2.05 fb[superscript −1] of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. The t[bar over t] events are selected in the dilepton decay channel with two identified b-jets from the top quark decays. Events are vetoed if they contain an additional jet with transverse momentum above a threshold in a central rapidity interval. The fraction of events surviving the jet veto is presented as a function of this threshold for four different central rapidity interval definitions. An alternate measurement is also perfor…

Top quarkPhysics and Astronomy (miscellaneous)Hadron7. Clean energy01 natural sciencesHigh Energy Physics - ExperimentQuark Pair ProductionHigh Energy Physics - Experiment (hep-ex)[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Detectors de radiacióPhysicsddc:539Jet (fluid)Large Hadron ColliderLuminosity (scattering theory)central jet activity; pp collisions; ATLAS detectorSettore FIS/01 - Fisica SperimentaleProduction Cross-SectionATLASmedicine.anatomical_structurePhysical SciencesComputingMethodologies_DOCUMENTANDTEXTPROCESSINGFísica nuclearLHCParticle Physics - ExperimentParticle physicsjet activityCiências Naturais::Ciências FísicasRegular Article - Experimental PhysicsScalar (mathematics):Ciências Físicas [Ciências Naturais]FOS: Physical sciencesddc:500.2530Partícules (Física nuclear)Nuclear physicsAtlas (anatomy)0103 physical sciencesmedicineFysikRapidityddc:530High Energy Physics010306 general physicsEngineering (miscellaneous)QUARK PAIR PRODUCTIONCiencias ExactasScience & TechnologyATLAS detector010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyHADRON-HADRON COLLISIONSCol·lisions (Física nuclear)Experimental High Energy PhysicsHigh Energy Physics::Experimentproton-proton collisions
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Some classes of topological quasi *-algebras

2001

The completion $\overline{A}[\tau]$ of a locally convex *-algebra $A [ \tau ]$ with not jointly continuous multiplication is a *-vector space with partial multiplication $xy$ defined only for $x$ or $y \in A_{0}$, and it is called a topological quasi *-algebra. In this paper two classes of topological quasi *-algebras called strict CQ$^*$-algebras and HCQ$^*$-algebras are studied. Roughly speaking, a strict CQ$^*$-algebra (resp. HCQ$^*$-algebra) is a Banach (resp. Hilbert) quasi *-algebra containing a C$^*$-algebra endowed with another involution $\sharp$ and C$^*$-norm $\| \|_{\sharp}$. HCQ$^*$-algebras are closely related to left Hilbert algebras. We shall show that a Hilbert space is a H…

Topological quasi *-algebraTopological algebraHilbert algebraApplied MathematicsGeneral MathematicsHilbert spaceRegular polygonFOS: Physical sciencesHCQ*-algebraMathematical Physics (math-ph)TopologyCQ*-algebrasymbols.namesakesymbolsSettore MAT/07 - Fisica MatematicaSubspace topologyMathematical PhysicsMathematics
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Trace and density results on regular trees

2019

We give characterizations for the existence of traces for first order Sobolev spaces defined on regular trees.

Trace (linear algebra)Mathematics::Analysis of PDEsBoundary (topology)01 natural sciencesMeasure (mathematics)Potential theorySet (abstract data type)Combinatoricsregular treeMathematics - Metric Geometry0103 physical sciencesEuclidean geometryClassical Analysis and ODEs (math.CA)FOS: Mathematics0101 mathematicsMathematicsdensityMathematics::Functional Analysis010102 general mathematicsMetric Geometry (math.MG)Functional Analysis (math.FA)Sobolev spaceMathematics - Functional AnalysisMathematics - Classical Analysis and ODEs010307 mathematical physicsTree (set theory)46E35 30L99funktionaalianalyysiAnalysisboundary traceNewtonian space
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Singular Neumann (p, q)-equations

2019

We consider a nonlinear parametric Neumann problem driven by the sum of a p-Laplacian and of a q-Laplacian and exhibiting in the reaction the competing effects of a singular term and of a resonant term. Using variational methods together with suitable truncation and comparison techniques, we show that for small values of the parameter the problem has at least two positive smooth solutions.

TruncationGeneral MathematicsResonant nonlinearity0211 other engineering and technologies02 engineering and technology01 natural sciencesPotential theoryTruncation and comparisonTheoretical Computer ScienceSettore MAT/05 - Analisi MatematicaNeumann boundary conditionApplied mathematics0101 mathematics(p q)-equationNonlinear regularityMathematicsParametric statistics021103 operations research010102 general mathematicsSingular termSingular termMathematics::Spectral TheoryOperator theoryTerm (time)Nonlinear systemNonlinear strong maximum principleAnalysisPositivity
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Multiple solutions for (p,2)-equations at resonance

2019

We consider a nonlinear nonhomogeneous Dirichlet problem driven by the sum of a p-Laplacian and a Laplacian and a reaction term which is (p− 1)-linear near ±∞ and resonant with respect to any nonprincipal variational eigenvalue of (−∆p, W01,p(Ω)). Using variational tools together with truncation and comparison techniques and Morse Theory (critical groups), we establish the existence of six nontrivial smooth solutions. For five of them we provide sign information and order them.

TruncationSettore MAT/05 - Analisi MatematicaComparison techniqueNonlinear maximum principleNodal solutionResonanceCritical groupConstant signNonlinear regularity
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