Search results for "Mathematica"

showing 10 items of 7971 documents

Female reproductive factors are associated with objectively measured physical activity in middle-aged women

2017

Physical activity improves health and may delay the onset of several chronic diseases. For women in particular, the rate of these diseases accelerates at middle age; therefore it is important to identify the determinants of health-enhancing physical activity during midlife in this population. In this study, we focused on determinants that are unique to the female sex, such as childbearing and menopause. The main objective was to characterize the level of physical activity and differences between active and inactive middle-aged Finnish women. In addition, we examined the association of physical activity with female reproductive factors at midlife. The study population consisted of 647 women …

vaihdevuodetPhysiologyMaternal Healthlcsh:Medicinephysical activitymenopauseMiscarriageBody Mass Index0302 clinical medicineMathematical and Statistical TechniquesPregnancyAccelerometryMedicine and Health SciencesMedicinePublic and Occupational Healthpelvic floor dysfunction030212 general & internal medicinelcsh:Scienceta315Reproductive HistoryFinlandeducation.field_of_study030219 obstetrics & reproductive medicineMultidisciplinaryPelvic floorObstetrics and Gynecologyta3142Middle AgedMenopausemedicine.anatomical_structurePhysiological ParametersCohortPhysical SciencesEngineering and TechnologyRegression AnalysisFemaleStatistics (Mathematics)Research ArticleUrologyPopulationLinear Regression AnalysisResearch and Analysis MethodsPelvic Floor Disordersmiddle-aged women03 medical and health sciencesPelvic floor dysfunctionPain ManagementHumansObesityStatistical MethodseducationExerciseIncontinencebusiness.industryBody Weightlcsh:RBiology and Life SciencesMyalgiaPelvic Floormedicine.diseaseta3123Middle agePregnancy ComplicationsLight intensityWomen's Healthlcsh:QElectronicsAccelerometersbusinessBody mass indexMathematicsDemographyPLoS ONE
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A systematic review of functional numeracy measures for 9–12 -year-olds: Validity and reliability evidence

2023

This systematic review aimed to summarize the characteristics and the measurement properties of functional numeracy measures developed for use by teachers among 9–12-year-old children with or without mathematical learning difficulties. A systematic search from five databases was conducted based on pre-defined criteria. PRISMA guidelines were followed for reporting the results. The terminology and classification of measurement properties adopted by the COSMIN taxonomy was used. Twenty-one studies of 18 measures met the inclusion criteria. Most of the identified measures did not report on several measurement properties due to incomplete or missing psychometric data. Knowledge of Mathematical …

validityreliabilityassessmentmittausCOSMIN taxonomyEducationoppimisvaikeudetvaliditeettifunctional numeracymittarit (mittaus)matemaattiset taidotmathematical learning difficultiessystemaattiset kirjallisuuskatsauksetreliabiliteettiInternational Journal of Educational Research
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The roles of achievement-related behaviours and parental beliefs in children´s mathematical performance

2003

This study aimed to investigate the developmental dynamics between children's mathematical performance, the task-focused versus task-avoidant behaviours they show in the classroom, and their parents' beliefs concerning their school competence. The mathematical performance of 111 six- to seven-year-old children was tested, and their task-focused versus task-avoidant behaviours were rated by their teachers four times during their first school year. Parents filled in questionnaires measuring their skill-specific and general beliefs about their children's school competencies at the beginning and at the end of the school year. The results showed that parents' beliefs in their children's general …

vanhempien uskomuksetSchool age childMathematical performancealkuopetuseducationlaskutaitoExperimental and Cognitive PsychologyAcademic achievementbehavioral disciplines and activitiesEducationDevelopmental psychologyDevelopmental dynamicsEl NiñoCorrelation analysisDevelopmental and Educational PsychologyMathematical abilityPsychologyCompetence (human resources)suoritusstrategiat
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Hölder regularity for the gradient of the inhomogeneous parabolic normalized p-Laplacian

2018

In this paper, we study an evolution equation involving the normalized [Formula: see text]-Laplacian and a bounded continuous source term. The normalized [Formula: see text]-Laplacian is in non-divergence form and arises for example from stochastic tug-of-war games with noise. We prove local [Formula: see text] regularity for the spatial gradient of the viscosity solutions. The proof is based on an improvement of flatness and proceeds by iteration.

viscosity solutionsApplied MathematicsGeneral Mathematicsta111010102 general mathematicsMathematical analysisparabolic01 natural sciencesNoise (electronics)non-homogeneouslocal C-alpha regularityTerm (time)010101 applied mathematicsViscosityBounded functionNon homogeneousEvolution equationp-Laplacian0101 mathematicsnormalized p-LaplacianFlatness (mathematics)MathematicsCommunications in Contemporary Mathematics
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Regularity for nonlinear stochastic games

2015

We establish regularity for functions satisfying a dynamic programming equation, which may arise for example from stochastic games or discretization schemes. Our results can also be utilized in obtaining regularity and existence results for the corresponding partial differential equations. peerReviewed

viscosity solutionsDiscretization01 natural sciencesMathematics - Analysis of PDEsBellman equationComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATIONFOS: MathematicsApplied mathematicstug-of-war0101 mathematicsMathematics - Optimization and ControlMathematical PhysicsMathematicsstokastiset prosessitPartial differential equationApplied Mathematics91A15 35J92 35B65 35J60 49N60010102 general mathematicsta111dynamic programming principletug-of-war with noise with space dependent probabilities010101 applied mathematicsNonlinear systemOptimization and Control (math.OC)p-LaplaceAnalysisAnalysis of PDEs (math.AP)
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Remarks on regularity for p-Laplacian type equations in non-divergence form

2018

We study a singular or degenerate equation in non-divergence form modeled by the $p$-Laplacian, $$-|Du|^\gamma\left(\Delta u+(p-2)\Delta_\infty^N u\right)=f\ \ \ \ \text{in}\ \ \ \Omega.$$ We investigate local $C^{1,\alpha}$ regularity of viscosity solutions in the full range $\gamma>-1$ and $p>1$, and provide local $W^{2,2}$ estimates in the restricted cases where $p$ is close to 2 and $\gamma$ is close to 0.

viscosity solutionsintegrability of second derivativesType (model theory)01 natural sciencesDivergencelocal C1ViscosityMathematics - Analysis of PDEsFOS: Mathematicspartial differential equations0101 mathematicsMathematicsMathematical physicsosittaisdifferentiaaliyhtälötα regularityApplied Mathematics010102 general mathematicsta111p-Laplacianlocal C1α regularityviskositeettiDegenerate equation35J60 35B65 35J92010101 applied mathematicsviscosityp-LaplacianAnalysisAnalysis of PDEs (math.AP)Journal of Differential Equations
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The ALICE experiment at the CERN LHC

2008

Journal of Instrumentation 3(08), S08002 (2008). doi:10.1088/1748-0221/3/08/S08002

visible and IR photonsLiquid detectorshigh energyPhotonPhysics::Instrumentation and DetectorsTransition radiation detectorsTiming detectors01 natural sciencesOverall mechanics designParticle identificationSoftware architecturesParticle identification methodsGaseous detectorscluster findingDetector cooling and thermo-stabilizationDetector groundingParticle tracking detectors[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Special cablesDetector alignment and calibration methodsDetectors and Experimental TechniquesNuclear ExperimentVoltage distributions.Photon detectors for UVInstrumentationMathematical PhysicsQuantum chromodynamicsPhysicsLarge Hadron ColliderSpectrometersPhysicsDetectorcalibration and fitting methodsTransition radiation detectorScintillatorsData processing methodsAnalysis and statistical methodsData reduction methodsParticle physicsCherenkov and transition radiationTime projection chambers610dE/dx detectorsNuclear physicsCalorimetersPattern recognitionGamma detectors0103 physical sciencesddc:610Solid state detectors010306 general physicsMuonInstrumentation for heavy-ion acceleratorsSpectrometerLarge detector systems for particle and astroparticle physics010308 nuclear & particles physicsCERN; LHC; ALICE; heavy ion; QGPCherenkov detectorsComputingVoltage distributionsManufacturingscintillation and light emission processesanalysis and statistical methods; calorimeters; cherenkov and transition radiation; cherenkov detectors; computing; data processing methods; data reduction methods; de/dx detectors; detector alignment and calibration methods; detector cooling and thermo-stabilization; detector design and construction technologies and materials; detector grounding; gamma detectors; gaseous detectors; instrumentation for heavy-ion accelerators; instrumentation for particle accelerators and storage rings - high energy; large detector systems for particle and astroparticle physics; liquid detectors; manufacturing; overall mechanics design; particle identification methods; particle tracking detectors; pattern recognition; cluster finding; calibration and fitting methods; photon detectors for uv; visible and ir photons; scintillators; scintillation and light emission processes; simulation methods and programs; software architectures; solid state detectors; special cables; spectrometers; time projection chambers; timing detectors; transition radiation detectors; voltage distributionsInstrumentation for particle accelerators and storage ringsInstrumentation; Mathematical PhysicsHigh Energy Physics::ExperimentSimulation methods and programsDetector design and construction technologies and materials
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Decoupled control scheme of grid-connected split-source inverters

2017

Grid-connected power conversion systems for renewable energy sources must fulfill several requirements, e.g., the high efficiency, the reduced cost and complexity, and, quite often, the boost capabilities that is usually achieved using a front-end dc–dc boost converter before the inversion stage, leading to a two-stage architecture. Meanwhile, single-stage power conversion systems, which perform the boosting operation within the inversion one, offer some potential advantages, in terms of reducing the complexity and the volume of the whole system. Among several proposed options, the split-source inverter (SSI) has been recently proposed by Abdelhakim et al. as an alternative option with some…

voltage-source inverter (VSI)EngineeringDecoupled control; grid connected; impedance-based inverters; renewable energy sources (RESs); single-stage; space vector; split-source inverter (SSI); synchronous reference frame; voltage-source inverter (VSI); Z-source inverter (ZSI); Control and Systems Engineering; Electrical and Electronic Engineering020209 energyModulation index02 engineering and technologySettore ING-INF/01 - Elettronicasynchronous reference frameControl theoryspace vector0202 electrical engineering electronic engineering information engineeringElectronic engineeringElectrical and Electronic EngineeringMATLABcomputer.programming_languagesplit-source inverter (SSI)Z-source inverter Decoupled control Grid-connected Impedance-based inverters Renewable energy sources Single-stage Space vector Split-source inverter Synchronous reference frame Voltage source inverter Mathematical model Inverters Modulation Switches Voltage control Standards Topologybusiness.industry020208 electrical & electronic engineeringInversion (meteorology)Z-source inverter (ZSI)Gridsingle-stageDecoupled controlControl and Systems Engineeringimpedance-based invertersBoost converterrenewable energy sources (RESs)Invertergrid connectedReduced costbusinesscomputerReference frame
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Relationship between volume and energy of vector fields

2001

Abstract A unified study of energy and volume functionals is presented here by determining the critical points of a functional that extends simultaneously energy and volume and that is defined on the product of the manifold of smooth maps C∞(M,N) times the manifold M of riemannian metrics on M. The restriction of this functional to different submanifolds of the space of vector fields X (M)× M is also considered, and used to study several functionals generalizing volume and energy or total bending of vector fields

volumeenergy and total bending of vector fieldscritical pointsMathematical analysisBendingVolume and energy functionalsSpace (mathematics)Manifoldvariational problemsComputational Theory and MathematicsVolume (thermodynamics)Product (mathematics)Fundamental vector fieldVector fieldGeometry and TopologyMathematics::Differential GeometryAnalysisEnergy (signal processing)MathematicsDifferential Geometry and its Applications
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Waste heat recovery from a marine waste incinerator using a thermoelectric generator

2012

Published version of an article published in the journal: Journal of Electronic Materials. Also available from the publisher at: http://dx.doi.org/10.1007/s11664-012-2009-6 A marine waste incinerator has been evaluated for waste heat harvesting using thermoelectric generators (TEG). The application has been evaluated using mathematical modeling to optimize the heat exchanger and some vital design parameters of the TEG. The calculation shows that it is possible to extract 58 kW el at a price of 6.6 US$/W from an 850-kW th incinerator when optimizing for maximum power. However, minimizing the cost, it is possible to get 25 kW el at a price of 2.5 US$/W. A trade-off between the two targets lea…

waste heat recoveryMaximum power principleWaste managementVDP::Technology: 500::Marine technology: 580TEGwaste heatCondensed Matter PhysicsthermoelectricElectronic Optical and Magnetic MaterialsIncinerationWaste heat recovery unitThermoelectric generatorWaste heatmarine incineratorThermoelectric effectHeat exchangerMaterials ChemistryEnvironmental scienceElectrical and Electronic Engineeringmathematical model
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