Search results for "Regular"

showing 10 items of 855 documents

Restoration of Videos Degraded by Local Isoplanatism Effects in the Near-Infrared Domain

2008

When observing a scene horizontally at a long distance in the near-infrared domain, degradations due to atmospheric turbulence often occur. In our previous work, we presented two hybrid methods to restore videos degraded by such local perturbations. These restoration algorithms take advantages of a space-time Wiener filter and a space-time regularization by the Laplacian operator. Wiener and Laplacian regularization results are mixed differently depending on the distance between the current pixel and the nearest edge point. It was shown that a gradation between Wiener and Laplacian areas improves results quality, so that only the algorithm using a gradation will be used in this article. In …

Computer engineering. Computer hardwareComputer scienceComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONRegularization (mathematics)Image (mathematics)Local degradationAdaptive restorationTK7885-7895symbols.namesakeSegmentationComputer visionPixelbusiness.industryWiener filterAtmospheric turbulenceImage and Video ProcessingVideo SurveillanceQA75.5-76.95Video processingElectronic computers. Computer sciencesymbolsGradationComputer Vision and Pattern RecognitionArtificial intelligenceAutomatic segmentationbusinessLaplace operatorSoftwareELCVIA: electronic letters on computer vision and image analysis
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An abstract inf-sup problem inspired by limit analysis in perfect plasticity and related applications

2021

This paper is concerned with an abstract inf-sup problem generated by a bilinear Lagrangian and convex constraints. We study the conditions that guarantee no gap between the inf-sup and related sup-inf problems. The key assumption introduced in the paper generalizes the well-known Babuška–Brezzi condition. It is based on an inf-sup condition defined for convex cones in function spaces. We also apply a regularization method convenient for solving the inf-sup problem and derive a computable majorant of the critical (inf-sup) value, which can be used in a posteriori error analysis of numerical results. Results obtained for the abstract problem are applied to continuum mechanics. In particular…

Computer scienceApplied MathematicsRegular polygonDuality (optimization)Bilinear interpolationPlasticityRegularization (mathematics)Mathematics::Numerical Analysissymbols.namesakeLimit analysisTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYModeling and SimulationConvex optimizationsymbolsApplied mathematicsLagrangianMathematical Models and Methods in Applied Sciences
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From the nearest neighbour rule to decision trees

1998

This paper proposes an algorithm to design a tree-like classifier whose result is equivalent to that achieved by the classical Nearest Neighbour rule. The procedure consists of a particular decomposition of a d-dimensional feature space into a set of convex regions with prototypes from just one class. Some experimental results over synthetic and real databases are provided in order to illustrate the applicability of the method.

Computer scienceFeature vectorDecision treeRegular polygonNearest neighbourNearest neighbour distributionClassifier (UML)Algorithm
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CRISPR sequences are sometimes erroneously translated and can contaminate public databases with spurious proteins containing spaced repeats

2020

© The Author(s) 2020.

Computer scienceGene predictionGenomicscomputer.software_genreGeneral Biochemistry Genetics and Molecular BiologyHomology (biology)03 medical and health sciencesAnnotation0302 clinical medicineCRISPRClustered Regularly Interspaced Short Palindromic RepeatsDatabases Protein030304 developmental biology0303 health sciencesDatabasePalindromeProteinsComputational geneGenomicsAcademicSubjects/SCI00960Original ArticleUniProtGeneral Agricultural and Biological Sciencescomputer030217 neurology & neurosurgeryInformation Systems
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Total Variation Regularization in Digital Breast Tomosynthesis

2013

We developed an iterative algebraic algorithm for the reconstruction of 3D volumes from limited-angle breast projection images. Algebraic reconstruction is accelerated using the graphics processing unit. We varied a total variation (TV)-norm parameter in order to verify the influence of TV regularization on the representation of small structures in the reconstructions. The Barzilai-Borwein algorithm is used to solve the inverse reconstruction problem. The quality of our reconstructions was evaluated with the Quart Mam/Digi Phantom, which features so-called Landolt ring structures to verify perceptibility limits. The evaluation of the reconstructions was done with an automatic LR detection a…

Computer scienceGraphics processing unitInverseDigital Breast TomosynthesisTotal variation denoisingSolverAlgebraic numberAlgorithmRegularization (mathematics)Imaging phantom
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Group Nonnegative Matrix Factorization with Sparse Regularization in Multi-set Data

2021

Constrained joint analysis of data from multiple sources has received widespread attention for that it allows us to explore potential connections and extract meaningful hidden components. In this paper, we formulate a flexible joint source separation model termed as group nonnegative matrix factorization with sparse regularization (GNMF-SR), which aims to jointly analyze the partially coupled multi-set data. In the GNMF-SR model, common and individual patterns of particular underlying factors can be extracted simultaneously with imposing nonnegative constraint and sparse penalty. Alternating optimization and alternating direction method of multipliers (ADMM) are combined to solve the GNMF-S…

Computer scienceGroup (mathematics)020206 networking & telecommunications02 engineering and technologySparse approximationNon-negative matrix factorizationSet (abstract data type)Constraint (information theory)Computer Science::Computer Vision and Pattern Recognition0202 electrical engineering electronic engineering information engineeringSource separation020201 artificial intelligence & image processingJoint (audio engineering)Sparse regularizationAlgorithm2020 28th European Signal Processing Conference (EUSIPCO)
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Hartree-Fock-Bogoliubov solution of the pairing Hamiltonian in finite nuclei

2013

We present an overview of the Hartree-Fock-Bogoliubov (HFB) theory of nucleonic superfluidity for finite nuclei. After introducing basic concepts related to pairing correlations, we show how the correlated pairs are incorporated into the HFB wave function. Thereafter, we present derivation and structure of the HFB equations within the superfluid nuclear density functional formalism and discuss several aspects of the theory, including the unitarity of the Bogoliubov transformation in truncated single-particle and quasiparticle spaces, form of the pairing functional, structure of the HFB continuum, regularization and renormalization of pairing fields, and treatment of pairing in systems with …

Condensed Matter::Quantum GasesPhysicsUnitarityta114Nuclear TheoryHartree–Fock methodRenormalizationBogoliubov transformationsymbols.namesakeRegularization (physics)PairingsymbolsWave functionHamiltonian (quantum mechanics)Mathematical physics
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Structure and Thermodynamics of Binary Mixtures (Solutions)

2014

The concepts of chapter 2 are generalized to binary liquid mixtures (solutions). With the help of the concept of number and concentration fluctuations contact to the thermodynamics of solutions and physical chemistry of solutions is made. The perturbative RPA is shown to be equivalent to Flory’s theory of regular solutions. The phase diagrams of regular solutions and metal-salt solutions are discussed and explained in terms of the theories.

Condensed Matter::Soft Condensed MatterPhysicssymbols.namesakesymbolsRegular solutionStructure (category theory)Binary numberThermodynamicsGibbs free energyPhase diagram
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From Wigner-Yanase-Dyson conjecture to Carlen-Frank-Lieb conjecture

2020

Abstract In this paper we study the joint convexity/concavity of the trace functions Ψ p , q , s ( A , B ) = Tr ( B q 2 K ⁎ A p K B q 2 ) s , p , q , s ∈ R , where A and B are positive definite matrices and K is any fixed invertible matrix. We will give full range of ( p , q , s ) ∈ R 3 for Ψ p , q , s to be jointly convex/concave for all K. As a consequence, we confirm a conjecture of Carlen, Frank and Lieb. In particular, we confirm a weaker conjecture of Audenaert and Datta and obtain the full range of ( α , z ) for α-z Renyi relative entropies to be monotone under completely positive trace preserving maps. We also give simpler proofs of many known results, including the concavity of Ψ p…

ConjectureTrace (linear algebra)General Mathematics010102 general mathematicsRegular polygonPositive-definite matrix01 natural sciencesConvexitylaw.inventionCombinatoricsMonotone polygonInvertible matrixDyson conjecturelaw0103 physical sciences010307 mathematical physics0101 mathematicsMathematicsAdvances in Mathematics
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Separation properties of continuous maps in codimension 1 and geometrical applications

1992

Abstract Nuno Ballesteros, J.J. and M.C. Romero Fuster, Separation properties of continuous maps in codimension 1 and geometrical applications, Topology and its Applications 46 (1992) 107-111. We show that the image of a proper closed continuous map, f , from an n -manifold X to an ( n + 1)-manifold Y , such that H 1 (Y; Z 2 ) =0 , separates Y into at least two connected components provided the self-intersections set of f is not dense in any connected component of Y . We also obtain some geometrical applications.

Connected componentPure mathematicsContinuous mapImage (category theory)Alexander-Čech cohomology with compact supportCodimensionconvex curvesManifoldSet (abstract data type)Combinatoricsquasi-regular immersionsTangent developableGeometry and Topologyself-intersections setConnected componentstangent developableTopology (chemistry)MathematicsTopology and its Applications
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