Search results for "Quadrat"

showing 10 items of 344 documents

On Optimizing Locally Linear Nearest Neighbour Reconstructions Using Prototype Reduction Schemes

2010

This paper concerns the use of Prototype Reduction Schemes (PRS) to optimize the computations involved in typical k-Nearest Neighbor (k-NN) rules. These rules have been successfully used for decades in statistical Pattern Recognition (PR) applications, and have numerous applications because of their known error bounds. For a given data point of unknown identity, the k-NN possesses the phenomenon that it combines the information about the samples from a priori target classes (values) of selected neighbors to, for example, predict the target class of the tested sample. Recently, an implementation of the k-NN, named as the Locally Linear Reconstruction (LLR) [11], has been proposed. The salien…

Optimization problemComputer science020206 networking & telecommunications02 engineering and technologyReduction (complexity)Set (abstract data type)Data point0202 electrical engineering electronic engineering information engineeringFeature (machine learning)A priori and a posteriori020201 artificial intelligence & image processingPoint (geometry)Quadratic programmingAlgorithm
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2020

This work introduces a method to estimate reflectance, shading, and specularity from a single image. Reflectance, shading, and specularity are intrinsic images derived from the dichromatic model. Estimation of these intrinsic images has many applications in computer vision such as shape recovery, specularity removal, segmentation, or classification. The proposed method allows for recovering the dichromatic model parameters thanks to two independent quadratic programming steps. Compared to the state of the art in this domain, our approach has the advantage to address a complex inverse problem into two parallelizable optimization steps that are easy to solve and do not require learning. The p…

Parallelizable manifoldGeneral Computer Sciencebusiness.industryComputer scienceMultispectral imageComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION02 engineering and technologyInverse problem01 natural sciencesDomain (software engineering)010309 opticsSpecularity0103 physical sciences0202 electrical engineering electronic engineering information engineeringRGB color model020201 artificial intelligence & image processingSegmentationComputer visionArtificial intelligenceQuadratic programmingbusinessPeerJ Computer Science
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Hadronic light-by-light contribution to $(g-2)_\mu $ from lattice QCD: a complete calculation

2021

The European physical journal / C 81(7), 651 (2021). doi:10.1140/epjc/s10052-021-09455-4

Particle physicsmagnetic momentPhysics and Astronomy (miscellaneous)High Energy Physics::LatticeHadronNuclear TheoryLattice (group)hep-lat01 natural sciences530pi: massPionHigh Energy Physics - Latticemuon0103 physical sciencesddc:530010306 general physicsEngineering (miscellaneous)latticeParticle Physics - PhenomenologyPhysicsMuon010308 nuclear & particles physicsScattering[PHYS.HLAT]Physics [physics]/High Energy Physics - Lattice [hep-lat]High Energy Physics::Phenomenologylattice field theoryphoton photon: scatteringhep-phParticle Physics - LatticeFunction (mathematics)Lattice QCDtensionQuadrature (mathematics)High Energy Physics - Phenomenology[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]High Energy Physics::Experimentn-point function: 4statistical
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On the Construction of Optimum Categories in Biomedical Data Recognition Problems

1979

The recognition of patterns within sets of biomedical data involves the following problems: a) Proper recording of the data to be used b) Extraction of suitable features c) Choice of categories or classes which are relevant to the medical decision task d) Estimation of the underlying distributions in the case of using parametric methods e) Choice of an adequate classification rule Whereas a lot of theories and procedures exists for most of these steps — particularly in the field of computer-aided differential diagnosis of electrocardiograms (ECG) (see [6]) — there has been only rare considerations on the problems of definition of appropriate categories.

Pattern vectorComputer sciencebusiness.industryQuadratic classifierMachine learningcomputer.software_genreField (computer science)Task (project management)Biomedical dataClassification ruleParametric methodsArtificial intelligencebusinesscomputer
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Bond-Based 2D Quadratic Fingerprints in QSAR Studies: Virtual and In vitro Tyrosinase Inhibitory Activity Elucidation

2010

In this report, we show the results of quantitative structure–activity relationship (QSAR) studies of tyrosinase inhibitory activity, by using the bond-based quadratic indices as molecular descriptors (MDs) and linear discriminant analysis (LDA), to generate discriminant functions to predict the anti-tyrosinase activity. The best two models [Eqs (6) and (12)] out of the total 12 QSAR models developed here show accuracies of 93.51% and 91.21%, as well as high Matthews correlation coefficients (C) of 0.86 and 0.82, respectively, in the training set. The validation external series depicts values of 90.00% and 89.44% for these best two equations (6) and (12), respectively. Afterwards, a second …

PharmacologyVirtual screeningQuantitative structure–activity relationshipChemistryStereochemistryTyrosinaseOrganic ChemistryLinear discriminant analysisBiochemistrychemistry.chemical_compoundQuadratic equationDiscriminantMolecular descriptorDrug DiscoveryMolecular MedicineKojic acidChemical Biology & Drug Design
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Scaling and data collapse for the mean exit time of asset prices

2005

We study theoretical and empirical aspects of the mean exit time of financial time series. The theoretical modeling is done within the framework of continuous time random walk. We empirically verify that the mean exit time follows a quadratic scaling law and it has associated a pre-factor which is specific to the analyzed stock. We perform a series of statistical tests to determine which kind of correlation are responsible for this specificity. The main contribution is associated with the autocorrelation property of stock returns. We introduce and solve analytically both a two-state and a three-state Markov chain models. The analytical results obtained with the two-state Markov chain model …

Physics - Physics and SocietyFísica matemàticaFOS: Physical sciencesMarkov processPhysics and Society (physics.soc-ph)FOS: Economics and businessFINANCEsymbols.namesakeFRACTIONAL CALCULUSQuadratic equationEconometricsNonlinear systemsApplied mathematicsDISTRIBUTIONSTime seriesScalingBrownian motionMathematicsStatistical hypothesis testingRANDOM-WALKSStatistical Finance (q-fin.ST)Series (mathematics)Markov chainStochastic processSistemes no linealsPhysicsAutocorrelationQuantitative Finance - Statistical FinanceFísicaFLUCTUATIONSMathematical physicssymbolsContinuous-time random walk
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Dissecting the Hadronic Contributions to (g−2)μ by Schwinger’s Sum Rule

2018

The theoretical uncertainty of $(g\ensuremath{-}2{)}_{\ensuremath{\mu}}$ is currently dominated by hadronic contributions. In order to express those in terms of directly measurable quantities, we consider a sum rule relating $g\ensuremath{-}2$ to an integral of a photoabsorption cross section. The sum rule, attributed to Schwinger, can be viewed as a combination of two older sum rules: Gerasimov-Drell-Hearn and Burkhardt-Cottingham. The Schwinger sum rule has an important feature, distinguishing it from the other two: the relation between the anomalous magnetic moment and the integral of a photoabsorption cross section is linear, rather than quadratic. The linear property makes it suitable …

PhysicsAnomalous magnetic dipole moment010308 nuclear & particles physicsNuclear TheoryHadronGeneral Physics and AstronomyOrder (ring theory)01 natural sciencesQuadratic equation0103 physical sciencesSum rule in quantum mechanicsNuclear Experiment010306 general physicsNuclear theoryMathematical physicsPhysical Review Letters
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Inelastic scattering and interactions of three-wave parametric solitons.

2006

We study the interactions of velocity-locked three-wave parametric solitons in a medium with quadratic nonlinearity and dispersion. We reveal that the inelastic scattering between three-wave solitons and linear waves may be described in terms of analytical solutions with dynamically varying group velocity, or boomerons. Moreover, we demonstrate the elastic nature of three-wave soliton-soliton collisions and interactions.

PhysicsClassical mechanicsNonlinear Sciences::Exactly Solvable and Integrable SystemsQuantum electrodynamicsQuadratic nonlinearityDispersion (optics)Group velocityFOS: Physical sciencesInelastic scatteringNonlinear Sciences::Pattern Formation and SolitonsPhysics - OpticsParametric statisticsOptics (physics.optics)Physical review. E, Statistical, nonlinear, and soft matter physics
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An extrinsic interface developed in an equilibrium based finite element formulation

2019

Abstract The phenomenon of delamination in composite material is studied in the framework of hybrid equilibrium based formulation with extrinsic cohesive zone model. The hybrid equilibrium formulation is a stress based approaches defined in the class of statically admissible solutions. The formulation is based on the nine-node triangular element with quadratic stress field which implicitly satisfy the homogeneous equilibrium equations. The inter-element equilibrium condition and the boundary equilibrium condition are imposed by considering independent side displacement fields as interfacial Lagrangian variable, in a classical hybrid formulation. The hybrid equilibrium element formulation is…

PhysicsCohesive Zone Model Delamination Extrinsic interface Hybrid equilibrium elementBoundary (topology)02 engineering and technologyMechanics021001 nanoscience & nanotechnologyDisplacement (vector)Finite element methodStress (mechanics)Stress fieldCohesive zone model020303 mechanical engineering & transportsQuadratic equation0203 mechanical engineeringDamage mechanicsSettore ICAR/08 - Scienza Delle Costruzioni0210 nano-technologyEarth-Surface ProcessesProcedia Structural Integrity
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Watch-hand-like optical rogue waves in three-wave interactions

2015

11 págs.; 6 figs.; OCIS codes: (190.3100) Instabilities and chaos; (190.5530) Pulse propagation and temporal solitons; (190.4410) Nonlinear optics, parametric processes.

PhysicsDiffractionComputer simulationbusiness.industryOptical rogue wavesAtomic and Molecular Physics and OpticsOpticsAmplitudeQuadratic equationGroup velocityRogue wavebusinessNonlinear Sciences::Pattern Formation and SolitonsPhotonic-crystal fiberOptics Express
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