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ECG quality estimation
Pospíšil, Jan ; Smíšek, Radovan (referee) ; Smital, Lukáš (advisor)
This bachelor thesis deals with the question of estimation of the quality of the ECG signals, which is a key parameter for determining the diagnosis. The theoretical part deals with the basic knowledge concerning cardiac physiology, electrocardiography and finally the types of interferences that can occur during the measurement. The following practical part will deal with the published methods and the proposal of methods for estimating signal quality and their testing on artificial and real data.
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Optimal detection of the Twave end in ECG signals
Lorenc, Patrik ; Kozumplík, Jiří (referee) ; Vítek, Martin (advisor)
This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.
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Wavelet Filtering of ECG Signals
Mrázek, Jiří ; Vítek, Martin (referee) ; Smital, Lukáš (advisor)
This thesis deals myopotential denoising of ECG signals with using wavelet transform. There was used wavelet denoising subsequently wiener wavelet filtering. In both cases were found the most suitable coeficients for the best denoising. It is meant mainly settings suitable parameters for ideal filtration setting value of threshold, number of decomposition level, selection of thresholding and type of filter. These parameters are tested on real signals. Denoising is realized in Matlab version R2009b.
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Image noise reduction method based on discrete wavelet transform
Holiš, Michal ; Přinosil, Jiří (referee) ; Malý, Jan (advisor)
This bachelor's thesis contains theoretical treatise on noises, which occur in digital visual data, their classification and possibilities of their removal. The next part is applied to theory of wavelets, wavelet transforms and their usage in working with one-dimensional, but mostly with two-dimensional signals. It is than mainly applied on visual data with a view to removing of failures contained in these data. The last part of the thesis is about implementation of demonstrational programme. This programme is created for removing of noise from the chosen visual data on the basis of user's chosen variables.
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Wiener Wavelet Filtering of ECG Signals
Sizov, Vasily ; Vítek, Martin (referee) ; Kozumplík, Jiří (advisor)
Tato práce se zabývá možností využití vlnkové transformace v aplikacích, které se zabývají potlačením šumu. Především se jedná o oblast filtrace signálu EKG. Úkolem je zhodnotit vliv různých parametrů nastavení samotné filtrace a zjistit jaký vliv má různé nastavení prahování wavelet koeficientů. Výsledkem práce je také stanovení hodnot prahů, stanovení nejlepšího způsobu rozkladu signálu a volba rekonstrukčních bank filtrů. Text obsahuje výsledky Wienerovy filtrace, při které byly testovány různé banky rozkladových a rekonstrukčních filtrů.Všechny popsané filtrační metody byly testovány na reálných záznamech EKG s aditivním myopotenciálním šumem. Algoritmy byly realizovány v prostředí MATLAB.
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Liveness Detection on Touchless Fingerprint Scanner
Fořtová, Kateřina ; Kanich, Ondřej (referee) ; Heidari, Mona (advisor)
This Bachelor's Thesis is focused on liveness detection of fingerprints with using touchless sensor. Work summarizes theoretical introduction to biometrics, fingerprint processing and some of present researches for liveness detection. The new approach is introduced with using Local Binary Pattern algorithm, Sobel and Laplacian operator and Wavelet transform. Artificial Neural Networks, Support Vector Machines and Decision Trees were used for final classification. Several experiments with dataset illuminated by lights with various wavelengths were realized. It was discovered, that fingerprints illuminated by red light reached the best accuracy 90.1% compared to other considered wavelenghts of visible light. The classification with vector based on Local Binary Pattern achieved average accuracy 89.8%, accuracy with vector based on Sobel and Laplacian operator was 91.5%. Several Wavelet families were used for Wavelet transform during experiments. The best accuracy achieved wavelets of Biorthogonal spline wavelet family (85.1%) and wavelets from Reverse biorthogonal spline wavelet family (86.6%).
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Biosignal processing - clusetr analysis
Příhodová, Petra ; Maděránková, Denisa (referee) ; Kolářová, Jana (advisor)
This thesis deals with the problem with cluster analysis and biosignal classification options. The principle of cluster analysis, methods for calculating distances between objects and the standard process in the implementation of clustering are described in the first part. For biosignals processing,it is necessary to get familiar with the primary parameters of these signals in the following sections of thesis, process biosignals and methods for recording of action potentials described. Based on studying different clustering methods is presented a program with the applied method kmedoid in the next section of this thesis. The steps of this program are described in detail and in the end of thesis functionality is tested on a database of signals ÚBMI.
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Optimal detection of the Twave end in ECG signals
Lorenc, Patrik ; Kozumplík, Jiří (referee) ; Vítek, Martin (advisor)
This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.
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Multilead decision rules in delineation of ECG signals
Richter, Zdeněk ; Smital, Lukáš (referee) ; Vítek, Martin (advisor)
This work deals with ECG signal measuring and methods of its processing. It compares some of the QRS detection methods and describes some of the testing databases. In this work a detector of QRS complex is realized, it is based on the approach of zero crossings. Next section makes combination of results from separate leads to one, which improves efficiency of detection. One section of this work deals with design and realization delination of ECG signal. In the last part outputs of this delineation are compared with the results of the other authors.
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Delineation of ECG signals using leads transformation
Ondroušek, Lukáš ; Ronzhina, Marina (referee) ; Vítek, Martin (advisor)
The goal of this work is to study the principles of delineation of ECG signals, wavelet transformation and transformation approaches to increase the number of available leads. Consequently, the knowledge was used to create delineation algorithm in Matlab. The algorithm was tested on complete CSE database. The obtained results were compared with the criteria which are set for the CSE database. In this work were realized six transformation approaches to increase the number of available leads. All of them were analyzed by delineation algorithm. In the work was examined, whether the transformation increase the efficiency of detection.
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