Search results for " space"

showing 10 items of 4562 documents

Quantifying brain tumor tissue abundance in HR-MAS spectra using non-negative blind source separation techniques

2012

Given high-resolution magic angle spinning (HR-MAS) spectra from several glial tumor subjects, our goal is to differentiate between tumor tissue types by separating the different sources that contribute to the profile of each spectrum. Blind source separation techniques are applied for obtaining characteristic profiles for necrosis, highly cellular tumor and border tumor tissue and providing the contribution (abundance) of each of these tumor tissue types to the profile of each spectrum. The problem is formulated as a non-negative source separation problem. Non-negative matrix factorization, convex analysis of non-negative sources and non-negative independent component analysis methods are …

Convex analysisApplied MathematicsAnalytical chemistryGlial tumorIndependent component analysisBlind signal separation030218 nuclear medicine & medical imagingAnalytical ChemistryMatrix decomposition03 medical and health sciences0302 clinical medicineDimension (vector space)Magic angle spinningSource separationBiological system030217 neurology & neurosurgeryMathematicsJournal of Chemometrics
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A four vertex theorem for strictly convex space curves

1993

Convex analysisDiscrete mathematicsConvex hullConvex setSpace curfFour-vertex theoremVertex theoremKrein–Milman theoremConvex spaceStrictly convex spaceVertex (curve)Danskin's theoremGeometry and TopologyMathematics
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On the Euler-Lagrange inequality of a convex variational integral in Orlicz spaces

1987

Convex analysisInequalitymedia_common.quotation_subjectMathematical analysisRegular polygonLinear matrix inequalityMinkowski inequalityGeneral Earth and Planetary SciencesApplied mathematicsBirnbaum–Orlicz spaceLp spaceJensen's inequalityGeneral Environmental Sciencemedia_commonMathematicsBanach Center Publications
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Non absolutely convergent integrals of functions taking values in a locally convex space

2006

Properties of McShane and Kurzweil-Henstock integrable functions taking values in a locally convex space are considered and the relations with other integrals are studied. A convergence theorem for the Kurzweil-Henstock integral is given

Convex analysisMcShane integralGeneral MathematicsMathematical analysisConvex setProper convex functionSubderivativeKurzweil-Henstock integralChoquet theory28B05McShaneintegral Pettis integralSettore MAT/05 - Analisi MatematicaLocally convex topological vector spacelocally convex spacesPettis integralConvex combinationAbsolutely convex setMathematics46G10
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Riemann type integrals for functions taking values in a locally convex space

2006

The McShane and Kurzweil-Henstock integrals for functions taking values in a locally convex space are defined and the relations with other integrals are studied. A characterization of locally convex spaces in which Henstock Lemma holds is given.

Convex analysisPure mathematicsGeneral MathematicsMathematical analysisMathematics::Classical Analysis and ODEsProper convex functionConvex setSubderivativeChoquet theoryLocally convex topological vector spaceConvex combinationPettis integral McShane integral Kurzweil-Henstock integral locally convex spacesAbsolutely convex setMathematicsCzechoslovak Mathematical Journal
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A constructive theory of shape

2021

We formulate a theory of shape valid for objects of arbitrary dimension whose contours are path connected. We apply this theory to the design and modeling of viable trajectories of complex dynamical systems. Infinite families of qualitatively similar shapes are constructed giving as input a finite ordered set of characteristic points (landmarks) and the value of a continuous parameter $\kappa \in (0,\infty)$. We prove that all shapes belonging to the same family are located within the convex hull of the landmarks. The theory is constructive in the sense that it provides a systematic means to build a mathematical model for any shape taken from the physical world. We illustrate this with a va…

Convex hullConnected spacePure mathematicsSeries (mathematics)Dynamical systems theoryPlane curveGeneral MathematicsApplied MathematicsGeneral Physics and AstronomyStatistical and Nonlinear PhysicsNumerical Analysis (math.NA)ConstructiveAttractorFOS: MathematicsMathematics - Numerical AnalysisParametric equationMathematics
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Strictly convex metric spaces with round balls and fixed points

2005

Convex hullConvex analysisStrictly convex spaceCombinatoricsInjective metric spaceMathematical analysisConvex setConvex bodyConvex combinationConvex metric spaceMathematicsBanach Center Publications
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R Code for Hausdorff and Simplex Dispersion Orderings in the 2D Case

2010

This paper proposes a software implementation using R of the Hausdorff and simplex dispersion orderings. A copy can be downloaded from http://www.uv.es/~ayala/software/fun-disp.R . The paper provides some examples using the functions exactHausdorff for the Hausdorff dispersion ordering and the function simplex for the simplex dispersion orderings. Some auxiliary functions are commented too.

Convex hullDiscrete mathematicsSimplexMultivariate random variableMathematicsofComputing_NUMERICALANALYSISHausdorff spaceAuxiliary functionFunction (mathematics)CombinatoricsTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYMathematics::Metric GeometryHausdorff measureStatistical dispersionMathematics
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Weak convergence theorems for asymptotically nonexpansive mappings and semigroups

2001

Convex hullDiscrete mathematicsWeak convergenceSemigroupApplied MathematicsBanach spaceErgodic theoryFixed-point theoremUniformly convex spaceFixed pointAnalysisMathematicsNonlinear Analysis: Theory, Methods & Applications
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Graph cut-based method for segmenting the left ventricle from MRI or echocardiographic images

2017

International audience; In this paper, we present a fast and interactive graph cut method for 3D segmentation of the endocardial wall of the left ventricle (LV) adapted to work on two of the most widely used modalities: magnetic resonance imaging (MRI) and echocardiography. Our method accounts for the fundamentally different nature of both modalities: 3D echocardiographic images have a low contrast, a poor signal-to-noise ratio and frequent signal drop, while MR images are more detailed but also cluttered and contain highly anisotropic voxels. The main characteristic of our method is to work in a 3D Bezier coordinate system instead of the original Euclidean space. This comes with several ad…

Convex hullHeart VentriclesEnergy MinimizationCoordinate systemEchocardiography Three-DimensionalHealth InformaticsBézier curve02 engineering and technology[SDV.IB.MN]Life Sciences [q-bio]/Bioengineering/Nuclear medicinecomputer.software_genreAutomated Segmentation030218 nuclear medicine & medical imaging[ SDV.IB.MN ] Life Sciences [q-bio]/Bioengineering/Nuclear medicine03 medical and health sciences0302 clinical medicineVoxelCut0202 electrical engineering electronic engineering information engineering[INFO.INFO-IM]Computer Science [cs]/Medical ImagingMagnetic-Resonance ImagesHumansRadiology Nuclear Medicine and imagingComputer vision[ SDV.IB ] Life Sciences [q-bio]/BioengineeringCardiac MriImage gradientMathematicsWhole MyocardiumLeft ventricular 3-D segmentationRadiological and Ultrasound Technology[ INFO.INFO-IM ] Computer Science [cs]/Medical ImagingEuclidean spacebusiness.industryComputer Graphics and Computer-Aided DesignMagnetic Resonance ImagingEchocardiographyConstrained Level-SetGraph (abstract data type)020201 artificial intelligence & image processing[SDV.IB]Life Sciences [q-bio]/BioengineeringComputer Vision and Pattern RecognitionArtificial intelligencebusiness2d-EchocardiographycomputerAlgorithmsGraph cutMRI
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