Search results for " analyysi"

showing 10 items of 155 documents

On a Continuous Sárközy-Type Problem

2022

Abstract We prove that there exists a constant $\epsilon> 0$ with the following property: if $K \subset {\mathbb {R}}^2$ is a compact set that contains no pair of the form $\{x, x + (z, z^{2})\}$ for $z \neq 0$, then $\dim _{\textrm {H}} K \leq 2 - \epsilon $.

Szemerédi’s theoremfractalsGeneral Mathematicspolynomitpolynomial configurationsHausdorff dimensionfraktaalitmittateoriafinite fieldsharmoninen analyysiFourier transforms of measuresminimeasuresInternational Mathematics Research Notices
researchProduct

Toimijuuden ja identiteetin yksilölliset ja sosiaaliset painotukset korkeakoulutettujen urapoluilla

2021

Tarkastelemme tutkimuksessa toimijuutta ja identiteettiä korkeakoulutettujen uratarinoissa. korkeakoulutettujen urapolkuja tutkimalla tunnistamme sekä korkeakoulutettujen urien rakentumisen tapoja että yksilön ja yhteiskunnan asettamien odotusten ja tavoitteiden merkitystä urapoluilla. Aineisto koostui Töissä.fi-verkkopalvelun kautta kerätyistä korkeakoulutettujen uratarinoista (N = 462). Tutkimusaineiston narratiivisessa analyysissa tarkastelimme, millaisia urapolkuja uratarinoista oli tunnistettavissa sekä millaisia toimijuuden ja identiteetin yksilöllisiä ja sosiaalisia painotuksia uratarinat sisälsivät. Analyysin pohjalta loimme seitsemän uratyyppitarinaa, jotka nimesimme urapolun raken…

Tiedeartikkeliuratnarratiivinen analyysikorkeakoulutetuttyöuraidentiteettiGeneral MedicineGeneral ChemistrytoimijuusAikuiskasvatus
researchProduct

Rotational coherence imaging and control for CN molecules through time-frequency resolved coherent anti-Stokes Raman scattering

2011

Numerical wave packet simulations are performed for studying coherent anti-Stokes Raman scattering (CARS) for CN radicals. Electronic coherence is created by femtosecond laser pulses between the X²Σ and B²Σ states. Due to the large energy separation of vibrational states, the wave packets are superpositions of rotational states only. This allows for a specially detailed inspection of the second- and third-order coherences by a two-dimensional imaging approach. We present the time-frequency domain images to illustrate the intra- and intermolecular interferences, and discuss the procedure to rationally control and experimentally detect the interferograms in solid Xe environment. peerReviewed

Wave packetvibraatiotilatGeneral Physics and Astronomyrotaatiotilatvapaat radikaalit01 natural sciencesMolecular physicslaw.inventionsymbols.namesakeNuclear magnetic resonancecoherent antiStokes Raman scatteringlaw0103 physical sciencesCoherent anti-Stokes Raman spectroscopyPhysical and Theoretical Chemistry010306 general physicsta116010304 chemical physicsta114rotationla statesChemistryIntermolecular forcekoherentti anti-Stokes Raman spektroskopiaLaserTime–frequency analysisFemtosecondsymbolshiiliyhdisteetcarbon comboundsnumeerinen analyysivibrational statesRaman scatteringCoherence (physics)The Journal of Chemical Physics
researchProduct

Higher-order Hamilton–Jacobi perturbation theory for anisotropic heterogeneous media: dynamic ray tracing in Cartesian coordinates

2018

With a Hamilton–Jacobi equation in Cartesian coordinates as a starting point, it is common to use a system of ordinary differential equations describing the continuation of first-order derivatives of phase-space perturbations along a reference ray. Such derivatives can be exploited for calculating geometrical spreading on the reference ray and for establishing a framework for second-order extrapolation of traveltime to points outside the reference ray. The continuation of first-order derivatives of phase-space perturbations has historically been referred to as dynamic ray tracing. The reason for this is its importance in the process of calculating amplitudes along the reference ray. We exte…

Wave propagationBody wavesta1171body waveswave propagation010502 geochemistry & geophysics01 natural sciencesHamilton–Jacobi equationlaw.inventionGeochemistry and PetrologylawaaltoliikeCartesian coordinate system0101 mathematicsAnisotropy0105 earth and related environmental sciencesPhysics010102 general mathematicsMathematical analysista111computational seismologynumerical modellingseismic anisotropyseismologiaRay tracing (physics)Geophysicsnumeerinen analyysiapproksimointidifferentiaaliyhtälötComputational seismologynumerical approximations and analysis
researchProduct

Analysis of errors caused by incomplete knowledge of material data in mathematical models of elastic media

2011

a posteriori error estimatesosittaisdifferentiaaliyhtälötDifferential equations Elliptictarkkuusfunctional deviation estimatesapproximation errorindeterminate datalinear elasticityDifferential equations PartialPDEepätarkkuuspartial differential equationsnumeerinen analyysimatemaattiset mallituncertaintytietojenkäsittelylaskentamenetelmät
researchProduct

Students at the core of English-medium instruction : research on the study paths of international master's degree students and the role of academic E…

2018

The present study focuses on the International Master’s Degree Programs (IMDP) of the University of Jyväskylä and issues related to English-medium instruction (EMI). At the core of the present study are the IMDP students’ conceptualizations of, and reflections on, academic English. Furthermore, the study examines the IMDP students’ reported language gains in academic English as well as the internal and external factors to which the students’ attribute these gains, or the lack of them. In order to map out these aspects, 15 IMDP students were interviewed at the end of their two-year program. These interviews were then analyzed inductively with the help of Atlas.ti software and by adhering to …

academic Englishtekstitaitokielitaitokorkeakoulututkinnotkorkeakouluopetussisällönanalyysiacademic literacieskvalitatiivinen analyysistudent's perspectivevieraskielinen opetusdiskurssikorkea-asteen koulutuslukutaitokirjoitustaitoLaadullinen sisällönanalyysiopetuskieliqualitative content analysisenglannin kieliEnglish-medium instruction
researchProduct

A Kinematic Analysis of Three Best 100 m Performances Ever

2013

The purpose of this investigation was to compare and determine the relevance of the morphological characteristics and variability of running speed parameters (stride length and stride frequency) between Usain Bolt’s three best 100 m performances. Based on this, an attempt was made to define which factors determine the performance of Usain Bolt's sprint and, therefore, distinguish him from other sprinters. We analyzed the previous world record of 9.69 s set in the 2008 Beijing Olympics, the current record of 9.58 s set in the 2009 Berlin World Championships in Athletics and the O lympic record of 9.63 s set in 2012 London Olympics Games by Usain Bolt. The application of VirtualDub Programme …

anthropometric characteristicskinematic analysismaailmanennätyskinemaattinen analyysiworld recordpikajuoksuantropometria
researchProduct

Optimal recovery of a radiating source with multiple frequencies along one line

2020

We study an inverse problem where an unknown radiating source is observed with collimated detectors along a single line and the medium has a known attenuation. The research is motivated by applications in SPECT and beam hardening. If measurements are carried out with frequencies ranging in an open set, we show that the source density is uniquely determined by these measurements up to averaging over levelsets of the integrated attenuation. This leads to a generalized Laplace transform. We also discuss some numerical approaches and demonstrate the results with several examples.

attenuated Radon transformMultispectralRAYUniqueness theorem01 natural sciencesinversio-ongelmat44A10 (Primary) 65R32 44A60 46N40 65Z05 (Secondary)030218 nuclear medicine & medical imaging0302 clinical medicine111 MathematicsDiscrete Mathematics and CombinatoricstietokonetomografiaPharmacology (medical)INVERSIONnuclear medicineBeam hardeningPhysicsLaplace transformDetectorNumerical Analysis (math.NA)Inverse problemuniqueness theoremFunctional Analysis (math.FA)Mathematics - Functional AnalysisMultiplicative system theoremkuvantaminensovellettu matematiikkaModeling and SimulationSPECTLine (geometry)numeerinen analyysipositroniemissiotomografiaemission computed tomographyAttenuated Radon transformEmission computed tomographyControl and OptimizationLaplace transformmultispectralOpen setCollimated light03 medical and health sciencesnuclear medicine.multiplicative system theoremFOS: Mathematicsinverse source problemMathematics - Numerical Analysis0101 mathematicsAttenuation010102 general mathematicsInverse source problemRangingComputational physicsTENSOR TOMOGRAPHYPETbeam hardeningNuclear MedicineAnalysis
researchProduct

Examining stability of independent component analysis based on coefficient and component matrices for voxel-based morphometry of structural magnetic …

2018

Independent component analysis (ICA) on group-level voxel-based morphometry (VBM) produces the coefficient matrix and the component matrix. The former contains variability among multiple subjects for further statistical analysis, and the latter reveals spatial maps common for all subjects. ICA algorithms converge to local optimization points in practice and the mostly applied stability investigation approach examines the stability of the extracted components. We found that the practically stable components do not guarantee to produce the practically stable coefficients of ICA decomposition for the further statistical analysis. Consequently, we proposed a novel approach including two steps: …

back-projectioncomponent matrixaivokuoridiabetescoefficient matrixvoxel-based morphometrysignaalianalyysimagneettitutkimusriippumattomien komponenttien analyysiMontreal cognitive assessmentstability
researchProduct

Korpusavusteinen virheanalyysi tarkkuuden kehityksestä EVK:n taitotasoilla A2–B2

2020

Artikkelissa tarkastellaan kielitaidon taitotasoittaista kehittymistä potentiaalisten esiintymien analyysin (Potential Occasion Analysis, Thewissen, 2015) avulla. Kehittymistä analysoidaan tarkkuuden näkökulmasta, ja sitä mitataan kohdekielen muoto- ja käyttökonventioista poikkeavien muotojen määrällä. Tutkimus on korpuspohjaista virheanalyysia (Corpus-aided Error Analysis, Dagneaux, Dennes & Granger, 1998), ja se perustuu taitotasoilla havaittujen, yhdeksään virheluokkaan sijoittuvien virheiden määrien tilastolliseen testaukseen. Aineistona on Kansainvälinen oppijansuomen korpus(ICLFI). Analyysi osoittaa, että merkittävintä kehitys on tasojen B1 ja B2 välillä; tasojen A2 ja B1 välillä tark…

corpus-aided error analysispotential occasion analysisaccuracytarkkuusPoint (typography)Computer sciencepotentiaalisten esiintymien analyysidevelopment of language proficiencykielitaitoLinguisticsRegressionCulminationkielitaidon kehittyminenError analysisPhraseologyGeneral Earth and Planetary SciencesLanguage proficiencykehityskorpusavusteinen virheanalyysiGeneral Environmental ScienceStatistical hypothesis testingPuhe ja kieli
researchProduct