Search results for "spektrianalyysi"

showing 5 items of 5 documents

MATLAB codes implementing the generalized cross-wavelet transform (GXWT) algorithm described in the paper "Analyzing multidimensional movement intera…

2021

MATLAB codes implementing the generalized cross-wavelet transform (GXWT) algorithm described in the paper "Analyzing multidimensional movement interaction with generalized cross-wavelet transform" (Toiviainen & Hartmann, 2021). Basic workflow for multivariate (time by channel) signals d1 and d2: [w1,f] = cwtensor(d1,FS,MINF,MAXF); [w2,f] = cwtensor(d2,FS,MINF,MAXF); [xs p1 p2] = getxwt(w1,w2); NOTE: cwtensor.m requires the Wavelet Toolbox for MATLAB.

MATLABcoordinationvuorovaikutusfrequencytaajuusinteractionspectrum analysiskoordinaatiospektrianalyysi
researchProduct

Spectral analysis and quantum chaos in two-dimensional nanostructures

2015

This thesis describes a study into the eigenvalues and eigenstates of twodimensional (2D) quantum systems. The research is summarized in four scientific publications by the author. The underlying motivation for this work is the grand question of quantum chaos: how does chaos, as known in classical mechanics, manifest in quantum mechanics? The search and analysis of these quantum fingerprints of chaos requires efficient numerical tools and methods, the development of which is given a special emphasis in this thesis. The first publication in this thesis concerns the eigenspectrum analysis of a nanoscale device. It is shown that a measured addition energy spectrum can be explained by a simple …

kaaosteoriaominaisarvotnumeeriset menetelmätkaksiulotteisuusEigenvaluesSpectrum analysisNanostructuresnanorakenteetkvanttikaaosQuantum systemskvanttimekaniikkaQuantum chaosNumerical analysisspektrianalyysi
researchProduct

Assessment of nonnegative matrix factorization algorithms for electroencephalography spectral analysis.

2020

AbstractBackgroundNonnegative matrix factorization (NMF) has been successfully used for electroencephalography (EEG) spectral analysis. Since NMF was proposed in the 1990s, many adaptive algorithms have been developed. However, the performance of their use in EEG data analysis has not been fully compared. Here, we provide a comparison of four NMF algorithms in terms of accuracy of estimation, stability (repeatability of the results) and time complexity of algorithms with simulated data. In the practical application of NMF algorithms, stability plays an important role, which was an emphasis in the comparison. A Hierarchical clustering algorithm was implemented to evaluate the stability of NM…

lcsh:Medical technologyComputer scienceBiomedical EngineeringStability (learning theory)ElectroencephalographySignal-To-Noise RatioClusteringNon-negative matrix factorizationBiomaterialsNonnegative matrix factorization03 medical and health sciencesklusterit0302 clinical medicineEeg dataalgoritmitmedicineHumansRadiology Nuclear Medicine and imagingSpectral analysisstabiilius (muuttumattomuus)EEGCluster analysisTime complexity030304 developmental biology0303 health sciencesRadiological and Ultrasound Technologymedicine.diagnostic_testResearchnonnegative matrix factorizationElectroencephalographySignal Processing Computer-AssistedGeneral MedicinestabilityModels TheoreticalHierarchical clusteringlcsh:R855-855.5AlgorithmStability030217 neurology & neurosurgeryAlgorithmsclusteringspektrianalyysiBiomedical engineering online
researchProduct

Numerical simulation of fluid-structure interaction between acoustic and elastic waves

2011

sovelluksetneste-rakenne-mallitfluid-structure interactionexact controllabilityspectral element methodcoupled problematk-ohjelmatacoustictietokonesimulaatiotelasticnumerical simulationtutkimusmenetelmätelastiset aallotwave equationsimulointiakustiset aallotspektrianalyysi
researchProduct

CMaS spektrianalysoinnin automatisointi

2011

Viimeisien vuosikymmenien aikana maailman sähkönkulutus on noussut tasaisesti. Tähän kehitykseen eri sähköntuottamisen teollisuuden alat ovat joutuneet vastaamaan lisäämällä tuotantokapasiteettiaan. Uusiutuvista energiamuodoista tuulienergia on lisännyt tuotantokapasiteettiaan ehkä eniten. Koko kehityksensä ajan tuulienergian tuotantokapasiteetin lisääntyminen on ollut eksponentiaalista ja tämän kehityksen ennustetaan myös jatkuvan. Samaan aikaan kilpailu tuuliturbiinien osien valmistajien välillä kiristyy. Erittäin tärkeänä osana kilpailussa on tuotteen mukana myytävät palvelut. Tästä hyvä esimerkki on tuuliturbiinien vaihteiden valmistajan Moventaksen myymä kunnonvalvontajärjestelmä. Kyse…

spektritvärähtelytvärähtelyspetkrianalyysituuliturbiiniturbiinitvärähtelyspektrispektrianalyysi
researchProduct