Search results for "Polynomial"

showing 10 items of 566 documents

Reliability of a new analysis to compute time to stabilization following a single leg drop jump landing in children.

2019

Although a number of different methods have been proposed to assess the time to stabilization (TTS), none is reliable in every axis and no tests of this type have been carried out on children. The purpose of this study was thus to develop a new computational method to obtain TTS using a time-scale (frequency) approach [i.e. continuous wavelet transformation (WAV)] in children. Thirty normally-developed children (mean age 10.16 years, SD = 1.52) participated in the study. Every participant performed 30 single-leg drop jump landings with the dominant lower limb (barefoot) on a force plate from three different heights (15cm, 20cm and 25cm). Five signals were used to compute the TTS: i) Raw, ii…

MaleResearch ValidityMuscle PhysiologyTime FactorsPhysiologyIntraclass correlationPolynomialsSignalRoot mean square0302 clinical medicineContinuous waveletStatisticsMedicine and Health SciencesBiomechanicsChildMusculoskeletal SystemReliability (statistics)MathematicsSignal processingMultidisciplinaryQRResearch AssessmentBiomechanical PhenomenaSignal FilteringPhysiological ParametersPhysical SciencesEngineering and TechnologyLegsMedicineFemaleAnatomyResearch ArticleMovementScienceResearch and Analysis Methods03 medical and health sciencesHumansMechanical PhenomenaLegBody WeightBiology and Life SciencesReproducibility of Results030229 sport sciencesAlgebraTransformation (function)Standard errorBody LimbsSignal ProcessingMusculoskeletal MechanicsMathematics030217 neurology & neurosurgeryPLoS ONE
researchProduct

Differentiation between acute and chronic myocardial infarction by means of texture analysis of late gadolinium enhancement and cine cardiac magnetic…

2017

[EN] The purpose of this study was to differentiate acute from chronic myocardial infarction using machine learning techniques and texture features extracted from cardiac magnetic resonance imaging (MRI). The study group comprised 22 cases with acute myocardial infarction (AMI) and 22 cases with chronic myocardial infarction (CMI). Cine and late gadolinium enhancement (LGE) MRI were analyzed independently to differentiate AMI from CMI. A total of 279 texture features were extracted from predefined regions of interest (ROIs): the infarcted area on LGE MRI, and the entire myocardium on cine MRI. Classification performance was evaluated by a nested cross-validation approach combining a feature…

Malemedicine.medical_specialtySupport Vector MachineMyocardial InfarctionContrast MediaMagnetic Resonance Imaging CineInfarctionGadolinium030204 cardiovascular system & hematologySensitivity and Specificity030218 nuclear medicine & medical imagingDiagnosis DifferentialTECNOLOGIA ELECTRONICA03 medical and health sciences0302 clinical medicinePolynomial kernelCardiac magnetic resonance imagingmedicineHumansLate gadolinium enhancementRadiology Nuclear Medicine and imagingMyocardial infarctioncardiovascular diseasesCardiac MRIChronic myocardial infarctionReceiver operating characteristicmedicine.diagnostic_testbusiness.industryMyocardiumReproducibility of ResultsGeneral MedicineMiddle Agedmedicine.diseaseSupport vector machineClassification Myocardial infarctionROC CurveTexture analysisArea Under CurveAcute DiseaseChronic Diseasecardiovascular systemFemaleRadiologyNuclear medicinebusinessAlgorithmsMagnetic Resonance Angiography
researchProduct

A new hyperelastic model for anisotropic hyperelastic materials with one fiber family

2016

International audience; The main goal of this study is to propose a practical application of a new family of transverse anisotropic invariants by designing a strain energy function (SEF) for incompressible fiber-reinforced materials. In order to validate the usability and creativeness of the proposed model, two different fiber-reinforced rubber materials under uniaxial and shear testing are considered. For each kind of material, numerical simulations based on the proposed model are consistent with experimental results and provide information about the effect of the new family of invariants in the construction of the SEF.

Materials science02 engineering and technologyStrain energy0203 mechanical engineeringNatural rubberGeneral Materials ScienceBiomechanicsAnisotropyPolynomial (hyperelastic model)Fiber (mathematics)business.industryApplied MathematicsMechanical EngineeringFunction (mathematics)Structural engineering[SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]021001 nanoscience & nanotechnologyCondensed Matter PhysicsAnisotropic hyperelasticity020303 mechanical engineering & transportsMechanics of MaterialsModeling and Simulationvisual_artHyperelastic materialvisual_art.visual_art_mediumCompressibilityTheory of invariant polynomials0210 nano-technologybusiness
researchProduct

Explicit polynomial solutions of fourth order linear elliptic Partial Differential Equations for boundary based smooth surface generation

2011

We present an explicit polynomial solution method for surface generation. In this case the surface in question is characterized by some boundary configuration whereby the resulting surface conforms to a fourth order linear elliptic Partial Differential Equation, the Euler–Lagrange equation of a quadratic functional defined by a norm. In particular, the paper deals with surfaces generated as explicit Bézier polynomial solutions for the chosen Partial Differential Equation. To present the explicit solution methodologies adopted here we divide the Partial Differential Equations into two groups namely the orthogonal and the non-orthogonal cases. In order to demonstrate our methodology we discus…

Mathematical analysisFirst-order partial differential equationExplicit and implicit methodsAerospace EngineeringPartial differential equationExplicit polynomial solutionExponential integratorComputer Graphics and Computer-Aided DesignParabolic partial differential equationSurface generationPDE surfaceLinear differential equationElliptic partial differential equationModeling and SimulationAutomotive EngineeringSymbol of a differential operatorMathematicsComputer Aided Geometric Design
researchProduct

Fully Polynomial Time Approximation Scheme for the Two-Parallel Capacitated Machines Scheduling Problem Under Unavailability Constraint

2010

Abstract Decision Support Systems (DSS) ensure the computer-based support for the conscientious decision-making in solving problems that require a large amount of information processing and complex scenarios. DSS for Transportation (DSST) are intelligent systems that are used at operational and organizational management levels. Operating a DSST in a public transportation web-based monitoring system is presented in this paper.

Mathematical optimizationDecision support systemJob shop schedulingbusiness.industryDistributed computingIntelligent decision support systemInformation processingGeneral MedicinePolynomial-time approximation schemeConstraint (information theory)Public transportUnavailabilitybusinessMathematicsIFAC Proceedings Volumes
researchProduct

Solving continuous models with dependent uncertainty: a computational approach

2013

This paper presents a computational study on a quasi-Galerkin projection-based method to deal with a class of systems of random ordinary differential equations (r.o.d.e.'s) which is assumed to depend on a finite number of random variables (r.v.'s). This class of systems of r.o.d.e.'s appears in different areas, particularly in epidemiology modelling. In contrast with the other available Galerkin-based techniques, such as the generalized Polynomial Chaos, the proposed method expands the solution directly in terms of the random inputs rather than auxiliary r.v.'s. Theoretically, Galerkin projection-based methods take advantage of orthogonality with the aim of simplifying the involved computat…

Mathematical optimizationPolynomial chaosArticle SubjectApplied Mathematicslcsh:MathematicsPolynomial chaoslcsh:QA1-939Projection (linear algebra)Orthogonal basisStochastic differential equationOrthogonalityStochastic differential equationsOrthonormal basisGalerkin methodMATEMATICA APLICADARandom variableAnalysisMathematics
researchProduct

Relaxed Stability and Performance LMI Conditions for Takagi-Sugeno Fuzzy Systems With Polynomial Constraints on Membership Function Shapes

2008

Most linear matrix inequality (LMI) fuzzy control results in literature are valid for any membership function, i.e., independent of the actual membership shape. Hence, they are conservative (with respect to other nonlinear control approaches) when specific knowledge of the shapes is available. This paper presents relaxed LMI conditions for fuzzy control that incorporate such shape information in the form of polynomial constraints, generalizing previous works by the authors. Interesting particular cases are overlap (product) bounds and ellipsoidal regions. Numerical examples illustrate the achieved improvements, as well as the possibilities of solving some multiobjective problems. The result…

Mathematical optimizationPolynomialApplied MathematicsPolynomial fuzzy systemsQuadratic stabilityLinear matrix inequalityFuzzy control systemNonlinear controlLinear matrix inequalityRelaxed conditionTakagi–Sugeno fuzzy controlDefuzzificationComputational Theory and MathematicsArtificial IntelligenceControl and Systems EngineeringRelaxed stabilityFuzzy numberParallel distributed compensationMembership functionMathematics
researchProduct

Decomposition of Dynamic Single-Product and Multi-product Lotsizing Problems and Scalability of EDAs

2008

In existing theoretical and experimental work, Estimation of Distribution Algorithms (EDAs) are primarily applied to decomposable test problems. State-of-the-art EDAs like the Hierarchical Bayesian Optimization Algorithm (hBOA), the Learning Factorized Distribution Algorithm (LFDA) or Estimation of Bayesian Networks Algorithm (EBNA) solve these problems in polynomial time. Regarding this success, it is tempting to apply EDAs to real-world problems. But up to now, it has rarely been analyzed which real-world problems are decomposable. The main contribution of this chapter is twofold: (1) It shows that uncapacitated single-product and multi-product lotsizing problems are decomposable. (2) A s…

Mathematical optimizationPolynomialDistribution (mathematics)Estimation of distribution algorithmComputer scienceBounded functionScalabilityEDASBayesian networkTime complexity
researchProduct

The multiple vehicle pickup and delivery problem with LIFO constraints

2015

Abstract This paper approaches a pickup and delivery problem with multiple vehicles in which LIFO conditions are imposed when performing loading and unloading operations and the route durations cannot exceed a given limit. We propose two mixed integer formulations of this problem and a heuristic procedure that uses tabu search in a multi-start framework. The first formulation is a compact one, that is, the number of variables and constraints is polynomial in the number of requests, while the second one contains an exponential number of constraints and is used as the basis of a branch-and-cut algorithm. The performances of the proposed solution methods are evaluated through an extensive comp…

Mathematical optimizationPolynomialInformation Systems and ManagementGeneral Computer ScienceManagement Science and Operations ResearchIndustrial and Manufacturing EngineeringTabu searchFIFO and LIFO accountingModeling and SimulationVehicle routing problemBenchmark (computing)Integer programmingAlgorithmBranch and cutInteger (computer science)MathematicsEuropean Journal of Operational Research
researchProduct

On the use of a meshless solver for PDEs governing electromagnetic transients

2009

In this paper some key elements of the Smoothed Particle Hydrodynamics methodology suitably reformulated for analyzing electromagnetic transients are investigated. The attention is focused on the interpolating smoothing kernel function which strongly influences the computational results. Some issues are provided by adopting the polynomial reproducing conditions. Validation tests involving Gaussian and cubic B-spline smoothing kernel functions in one and two dimensions are reported.

Mathematical optimizationPolynomialPartial differential equationApplied MathematicsB-splineNumerical analysisGaussianMeshless particle methodSmoothed Particle Hydrodynamics methodMaxwell's equationSolverSmoothed-particle hydrodynamicsSettore MAT/08 - Analisi NumericaSettore ING-IND/31 - ElettrotecnicaComputational Mathematicssymbols.namesakeElectromagnetic transientsymbolsApplied mathematicsSmoothingMathematicsApplied Mathematics and Computation
researchProduct