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Sleep scoring using EEG
Holdova, Kamila ; Smital, Lukáš (referee) ; Ronzhina, Marina (advisor)
This thesis deals with wavelet analysis of sleep electroencephalogram to sleep stages scoring. The theoretical part of the thesis deals with the theory of EEG signal creation and analysis. The polysomnography (PSG) is also described. This is the method for simultaneous measuring the different electrical signals; main of them are electroencephalogram (EEG), electromyogram (EMG) and electrooculogram (EOG). This method is used to diagnose sleep failure. Therefore sleep, sleep stages and sleep disorders are also described in the present study. In practical part, some results of application of discrete wavelet transform (DWT) for decomposing the sleep EEGs using mother wavelet Daubechies 2 „db2“ are shown and the level of the seven. The classification of the resulting data was used feedforward neural network with backpropagation errors.
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QRS detection based on Stockwell transform
Kašík, Ondřej ; Kozumplík, Jiří (referee) ; Smital, Lukáš (advisor)
This bachelor´s thesis deals with the detection of QRS complexes in ECG record. The thesis provides a brief information related to the heart anatomy, generation of electrical signals in the heart, recording and description of the ECG record. In more detail, there is a description of the detection of QRS complexes by various methods and realization of a detector based on Stockwell transform, Shannon energy and adaptive thresholding. The evaluation process of the detection efficiency is also included. Sensitivity and positive prediction of the proposed detector on the complete MIT-BIH Arrhythmia database reached 99.80 % and 99.88 % respectively.
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QRS complex detection in multilead ECG signals
Šlancar, Matěj ; Smital, Lukáš (referee) ; Kozumplík, Jiří (advisor)
The aim of this thesis is to introduce the principles of software QRS detection, which is based on different combinations of orthogonal (pseudoorthogonal) leads. The thesis describes the main components of the ECG signal, a selection of methods that can be used for QRS detection in orthogonal leads and finally the evaluation of the effectiveness of the chosen methods and a comparing the approaches with the results of other authors. Functionality of detection algorithm has been tested on signals of CSE standard library.
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ECG baseline wander correction based on the empirical mode decomposition
Šlancar, Matěj ; Smital, Lukáš (referee) ; Kozumplík, Jiří (advisor)
The aim of this thesis is to introduce with principle of Empirical Mode Decomposition method and possibility use for correction of baseline wander in ECG signals. The thesis describes the main components of the ECG signal, a selection of possible types of signal noise, its property and principles of chosen methods for filtration of ECG signals. In conclusion the evaluation of the effectiveness of the EMD method for filtering a baseline wander and it comparing with effectiveness of the linear filtration. Functionality of used algorithms has been tested on signals of CSE standard library.
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Biometric fingerprint identification
Dašek, Filip ; Vítek, Martin (referee) ; Smital, Lukáš (advisor)
In biometrics we use distinctive physical features for identification and verification of identity. The most famous technique is identification by fingerprints. This technique use unique structure created by papillary lines for unambiguous identification. Thesis contains methods which were created throughout the years for analysis and adjustments of fingerprint. The algorithm is based on compairng two pairs of minitua and calculating transform matrix for correct alignment. Algorithm is tested on dataset created from LivDet databases. Performance of algorithm is represented by value EER which is compared with EERs of other algorithms tested in FVC 2006.
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Automatic delineation of ECG signals
Žiak, Milan ; Smital, Lukáš (referee) ; Vítek, Martin (advisor)
This thesis deals about automatic delineation of ECG. We use algorithm, which is descriped by autors Lagune, Jané and Caminale. Their work uses first derivation for delineation ECG signal. This bachelor thesis also uses a wavelet transform to reach better results.
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Averaging of biological signals
Kubík, Adam ; Čmiel, Vratislav (referee) ; Smital, Lukáš (advisor)
The main aim of this thesis is to introduce issue of averaging of biological signals. The first part of the thesis deals with the principles of individual averaging methods (constant, floating and exponential window) and describes their basic features. Moreover, the principle of filtered residue, detection of QRS complex, and stretching/shrinking the length of RR-interval to the standardized length are explicated. In the second part of the thesis the outcomes of practically realized (Matlab and GUI) methods of averaging (by final signal-to-noise ratio) are evaluated. Signals from MIT-BIH database are used.
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P wave detection in ECG signals
Bajgar, Jiří ; Kozumplík, Jiří (referee) ; Smital, Lukáš (advisor)
The aim of this diploma thesis is to introduce methods of detection of the QRS complex and the subsequent detection of P waves. The intention is to create a program by specified method in the software Matlab which will be able to implement this method. The thesis describes the basic and important methods of detection and subsequent algorithm to detect P waves. Solution of the algorithm is tested on real data. It also describes the automatic signal evaluation and the results of this automatic function.
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Plagiarism detection of text documents
Lízal, Radek ; Vítek, Martin (referee) ; Smital, Lukáš (advisor)
This diploma thesis introduces the definition of plagiarism, distinguishes the types of plagiaries which often take place in praxis and the ways of determining the suspected texts. The means of detection are essential; therefore a whole chapter is dedicated to those. For the detection purposes, it is vital to pre-process the data to reduce the demand factor of the program. There is a preview of some programs which are already being used for the detection of plagiarism. The following chapter introduces some selected indications which have been implemented in the Matlab environment to create a detector of plagiaries in text documents. The created program is described in chapter eight. The applied indications and the detector response are described in a chapter called Indications testing. The testing proved the quality of these indications. The results together with pros and cons of the particular methods are discussed in the conclusion.
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Maximization of ECG signals diagnostic yield
Beháňová, Andrea ; Smital, Lukáš (referee) ; Vítek, Martin (advisor)
This bachelor thesis deals with the maximization of ECG signals diagnostic yield. In the theoretical section we deal with the physiology of the heart, electrocardiography, types of ECG noises. It describes some known methods for the estimation of quality of the ECG signal. The practical section contains two parts. The first one contains a continuous Signal-to-Noise Ratio (SNR). It includes generating artificial ECG signal, artificial myopotentials and implementation of Adaptive Wiener Wiener Filtrate (AWWF). After verification of the correctness of the filter on the artificial data, we started to use real data from MIT-BIH database. The second part involves a segmentation process that divides the ECG signal into three categories: a signal suitable for full analysis, suitable for detection of QRS complexes and a signal unsuitable for further analysis.
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