Search results for "mathematical analysis"

showing 10 items of 2409 documents

Mappings of finite distortion : removable singularities

2003

mathematical analysismatemaattinen analyysi
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Comparison of the Root Canal Curvatures of Human Teeth with the Curvatures of the Resin Blocks Used as Models for Training

2019

In this paper we develop a method to associate a function curvature to human teeth roots.These functions are calculated from radiographs using mathematical software. We use this procedure to compare the curvatures of the roots with the curvatures of the resin blocks that are used for learning. The comparison is made by calculating the distances of the corresponding functions in the \(L_1\) metric.

medicine.anatomical_structurePlane curveRoot canalMetric (mathematics)Mathematical analysisMathematical softwaremedicineMathematics::Differential GeometryFunction (mathematics)CurvatureMathematics
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Multi axis representation and Euclidean distance of muscle fatigue indexes during evoked contractions

2014

International audience; In this article, we proposed a new representation of muscular fatigue during evoked muscle contractions based on fatigue indexes such as peak to peak amplitude, RMS of the M wave, mean and median frequency and fatigue index calculated from continuous wavelet transform (I CWT). These new representations of muscle fatigue using multi axis represented and Euclidean distance give better insights on changes in physiological characteristics during muscle fatigue. This technique provides a fatigue index using several muscle characteristics. The use of other kinds of fatigue characteristics as force could also be possible.

medicine.diagnostic_testMuscle fatigueSpeech recognitionMulti axis0206 medical engineeringMathematical analysis02 engineering and technologyElectromyography[ SPI.SIGNAL ] Engineering Sciences [physics]/Signal and Image processing020601 biomedical engineering[ SPI.TRON ] Engineering Sciences [physics]/Electronics[SPI.TRON]Engineering Sciences [physics]/ElectronicsEuclidean distance03 medical and health sciences0302 clinical medicineAmplitudeMuscular fatiguemedicineRepresentation (mathematics)[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing030217 neurology & neurosurgeryContinuous wavelet transform[SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processingMathematics
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Mappings of finite distortion between metric measure spaces

2015

We establish the basic analytic properties of mappings of finite distortion between proper Ahlfors regular metric measure spaces that support a ( 1 , 1 ) (1,1) -Poincaré inequality. As applications, we prove that under certain integrability assumption for the distortion function, the branch set of a mapping of finite distortion between generalized n n -manifolds of type A A has zero Hausdorff n n -measure.

metric measure spacesPure mathematicsInjective metric spaceta111Mathematical analysisMathematicsofComputing_GENERALProduct metricEquivalence of metricsConvex metric spaceIntrinsic metricDistortion (mathematics)mappings of finite distortionMetric (mathematics)Metric mapGeometry and TopologyMathematicsConformal Geometry and Dynamics of the American Mathematical Society
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(p,2)-equations resonant at any variational eigenvalue

2018

We consider nonlinear elliptic Dirichlet problems driven by the sum of a p-Laplacian and a Laplacian (a (p,2) -equation). The reaction term at ±∞ is resonant with respect to any variational eigenvalue of the p-Laplacian. We prove two multiplicity theorems for such equations.

multiple solution01 natural sciencesResonance (particle physics)Dirichlet distributionsymbols.namesakeSettore MAT/05 - Analisi Matematicavariational eigenvalues0101 mathematicsEigenvalues and eigenvectorsMathematicsNumerical AnalysisApplied Mathematics010102 general mathematicsMathematical analysisp-LaplacianMathematics::Spectral TheoryTerm (time)010101 applied mathematicsComputational MathematicsNonlinear systemresonancecritical groupsymbolsp-Laplaciannonlinear regularity theoryLaplacianLaplace operatorAnalysis
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Global representation and multiscale expansion for the Dirichlet problem in a domain with a small hole close to the boundary

2019

For each pair (Formula presented.) of positive parameters, we define a perforated domain (Formula presented.) by making a small hole of size (Formula presented.) in an open regular subset (Formula presented.) of (Formula presented.) ((Formula presented.)). The hole is situated at distance (Formula presented.) from the outer boundary (Formula presented.) of the domain. Thus, when (Formula presented.) both the size of the hole and its distance from (Formula presented.) tend to zero, but the size shrinks faster than the distance. Next, we consider a Dirichlet problem for the Laplace equation in the perforated domain (Formula presented.) and we denote its solution by (Formula presented.) Our ai…

multiscale asymptotic expansionmulti-scale asymptotic expansionBoundary (topology)01 natural sciences35J25; 31B10; 45A05; 35B25; 35C20Domain (mathematical analysis)Settore MAT/05 - Analisi MatematicaSituated[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]Dirichlet problem; Laplace operator; multiscale asymptotic expansion; real analytic continuation in Banach space; singularly perturbed perforated domainSmall hole[MATH]Mathematics [math]0101 mathematicsRepresentation (mathematics)MathematicsDirichlet problemDirichlet problemApplied Mathematics010102 general mathematicsMathematical analysisA domain010101 applied mathematicssingularly perturbed perforated domainLaplace operatorLaplace operatorAnalysisreal analytic continuation in Banach space
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Constant Power Model in Arm Rotation—A New Approach to Hill’s Equation

2014

The purpose of this study was to further develop the constant power model of a previous study and to provide the final solution of Hill’s force-velocity equation. Forearm and whole arm rotations of three different subjects were performed downwards (elbow and shoulder extension) and upwards (elbow and shoulder flexion) with maximum velocity. These arm rotations were recorded with a special camera system and the theoretically derived model of constant maximum power was fitted to the experimentally measured data. The moment of inertia of the arm sectors was calculated using immersion technique for determining accurate values of friction coefficients of elbow and whole arm rotations. The experi…

muscle powerarm movementMaximum power principleMathematical analysisElbowMotion (geometry)Moment of inertiaRotationta3111force-velocity relationshipPower (physics)Moment (mathematics)Hill’s equationClassical mechanicsmedicine.anatomical_structuremedicineConstant (mathematics)ta315MathematicsWorld Journal of Mechanics
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Ghost stochastic resonance in FitzHugh–Nagumo circuit

2014

International audience; The response of a neural circuit submitted to a bi-chromatic stimulus and corrupted by noise is investigated. In the presence of noise, when the spike firing of the circuit is analysed, a frequency not present at the circuit input appears. For a given range of noise intensities, it is shown that this ghost frequency is almost exclusively present in the interspike interval distribution. This phenomenon is for the first time shown experimentally in a FitzHugh-Nagumo circuit.

noise[ INFO.INFO-TS ] Computer Science [cs]/Signal and Image ProcessingInterval distribution[ NLIN.NLIN-CD ] Nonlinear Sciences [physics]/Chaotic Dynamics [nlin.CD][ SPI.SIGNAL ] Engineering Sciences [physics]/Signal and Image processingStochastic ResonanceComputer Science::Hardware ArchitectureComputer Science::Emerging Technologies[NLIN.NLIN-PS]Nonlinear Sciences [physics]/Pattern Formation and Solitons [nlin.PS][INFO.INFO-TS]Computer Science [cs]/Signal and Image ProcessingElectronic engineering[ NLIN.NLIN-PS ] Nonlinear Sciences [physics]/Pattern Formation and Solitons [nlin.PS]Electrical and Electronic EngineeringMathematicsCircuit noiseQuantitative Biology::Neurons and CognitionArtificial neural networkStochastic processMathematical analysisneural networksFitzhugh nagumo[ SPI.TRON ] Engineering Sciences [physics]/Electronics[SPI.TRON]Engineering Sciences [physics]/ElectronicsHarmonics[NLIN.NLIN-CD]Nonlinear Sciences [physics]/Chaotic Dynamics [nlin.CD]Nonlinear network analysis[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processingElectronics Letters
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Gradient and Lipschitz Estimates for Tug-of-War Type Games

2021

We define a random step size tug-of-war game and show that the gradient of a value function exists almost everywhere. We also prove that the gradients of value functions are uniformly bounded and converge weakly to the gradient of the corresponding $p$-harmonic function. Moreover, we establish an improved Lipschitz estimate when boundary values are close to a plane. Such estimates are known to play a key role in the higher regularity theory of partial differential equations. The proofs are based on cancellation and coupling methods as well as an improved version of the cylinder walk argument. peerReviewed

osittaisdifferentiaaliyhtälöt91A15 35B65 35J92gradient regularityApplied MathematicsTug of warMathematical analysisstochastic two player zero-sum gameType (model theory)Lipschitz continuityComputational MathematicsMathematics - Analysis of PDEsLipschitz estimateBellman equationtug-of-war with noiseFOS: MathematicsUniform boundednesspeliteoriaAlmost everywherep-LaplaceValue (mathematics)AnalysisAnalysis of PDEs (math.AP)Mathematicsstokastiset prosessit
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Fixed Angle Inverse Scattering for Almost Symmetric or Controlled Perturbations

2020

We consider the fixed angle inverse scattering problem and show that a compactly supported potential is uniquely determined by its scattering amplitude for two opposite fixed angles. We also show that almost symmetric or horizontally controlled potentials are uniquely determined by their fixed angle scattering data. This is done by establishing an equivalence between the frequency domain and the time domain formulations of the problem, and by solving the time domain problem by extending the methods of [RS19] which adapts the ideas introduced in [BK81] and [IY01] on the use of Carleman estimates for inverse problems.

osittaisdifferentiaaliyhtälötApplied MathematicsMathematical analysisscattering amplitudePlane waveFOS: Physical sciencesplane waveMathematical Physics (math-ph)fixed angleinverse scattering01 natural sciencesinversio-ongelmat010101 applied mathematicsScattering amplitudeComputational MathematicsFixed angleMathematics - Analysis of PDEsInverse scattering problemFOS: Mathematics0101 mathematicsAnalysisMathematical PhysicsMathematicsAnalysis of PDEs (math.AP)
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