|
|
QRS detection using zero crossing counts
Kašák, Pavel ; Hrubeš, Jan (referee) ; Vítek, Martin (advisor)
This thesis is focusing on problems of detection of QRS complex. It includes basic description of ECG signal. It acquaints with common methods of searching QRS complex. Main attention is paid to detection based on zero crossing counts, which is realized by MATLAB program. This algorithm is then tested on CSE database, optimised and its efficiency is evaluated.
|
|
|
Detection of QRS complexes in ECG signals
Zhorný, Lukáš ; Ronzhina, Marina (referee) ; Kozumplík, Jiří (advisor)
This thesis deals with the detection of QRS complexes from electrocardiograms using time-frequency analysis. Detection procedures are based on wavelet and Stockwell transform. The theoretical part describes the basics of electrocardiography, then introduces common approaches to time-frequency analysis, such as short-time Fourier transform (STFT), wavelet transform and Stockwell transform. These algorithms were tested on a set of electrograms from the MIT-BIH and CSE-MO1 arrhythmia database. For the CSE database worked best the method based on the wavelet transform with the filter bank Symlet4, with the resulting value of sensitivity 100 % and positive predictivity 99.86%. For the MIT database had the best performance the detector using the Stockwell transform with values of sensitivity 99.54% and positive predictivity 99.68%. The results were compared with the values of other authors mentioned in the text.
|
|
|
Automatic sleep scoring using polysomnographic data
Kříženecká, Tereza ; Potočňák, Tomáš (referee) ; Ronzhina, Marina (advisor)
The thesis is focused on automatic classification of polysomnographic signals based on various parameters in time and frequency domain. The parameters are acquired from 30 seconds long segments of EEG, EMG and EOG signals recorded during different sleep stages. The parameters used for automatic classification of sleep stages are selected according to statistical analysis. Classification is performed using the SVM method and evaluation of the success of the classification is done using sensitivity, specificity and percentage success. Classification method was implemented using Matlab.
|
|
|
Automated Detection of graphic elements in EEG signal
Jančová, Ivana ; Ronzhina, Marina (referee) ; Bubník, Karel (advisor)
This thesis deals with the analysis of EEG, namely detection of graphic elements. The aim of the thesis is to describe methods suitable for detection of graphic elements and implementation of the two methods in MATLAB. The first part of the thesis describes the basics rhythms, artifacts and epileptiform transients occurring in the EEG. The second part deals with the methods of detection and their mutual comparison. The discussed methods are spectral analysis, correlation analysis, wavelet transform, cluster analysis and matched filter. Other parts of the thesis describe the database PhysioBank and implementation of the correlation analysis and matched filter. In the last part is the comparison of the success of selected methods and comparison is done by calculating sensitivity and positive predictive value.
|
|
|
Software for QRS detectors performance evaluation
Veverka, Vojtěch ; Vítek, Martin (referee) ; Ronzhina, Marina (advisor)
QRS complex is the most prominent part of ECG signal. Due to its properties, it is used in calculation of heart rate and serves as one of the reference points for automatic delineation of ECG. Therefore, the accurate detection of QRS complexes is very important. This work is focused on creating of software for evaluation of different QRS detection approaches. The first part includes the basics of electrocardiography, the most common methods for QRS detection and also various artifacts that can affect the detection, The practical part is focused on the development of some detectors and the software itself. The detectors are then tested with software using the CSE database of real ECG recordings.
|
|
|
Fingerprint biometry
Smékal, Ondřej ; Drahanský, Martin (referee) ; Fedra, Petr (advisor)
Algorithms designed for identification and verification persons by fingerprints recognition are spread and used as in forensics aplications as in private sector for a long time. The aim of this thesis is to make us aquainted with various aplicated mathematic models of fingerprint processing in digital way. Second task is the presentation algorithmic solution of chosen subject identification procedure by force of Fingerprint matching. Algorithm is solid in the development environment platform Matlab.
|
|
|
Social Games in Early Mother-Infant Interaction
Hrivíková, Zuzana ; Horáková Hoskovcová, Simona (advisor) ; Šulová, Lenka (referee)
The goal of this thesis was to study early social games in natural interaction between mother and child of 4 month age. Infant's affectivity and gaze orientation as a sign of participation was coded. We also observed how can mother and infant influence the social game routine. We examined mother's warm sensitivity and infant's temperament as a variables potentiallz influenced the social game interaction. Fifty five dyads participated in the present study when infants were four months old. Social games were analyzed in natural mother-infant interaction and identified on the given criterions. To assess maternal warm sensivity Materna Affect Attunement was used. Mother's evaluated infant's temperament on fourteen scales of IBQ-R. The results indicate that social games are an inherent part of mother-infant interactions in infant's 4 months of age, and their occurance is influenced by temperament. Keywords: play, game, social game routine, structure, social interaction, infant's positive affect infant age, sensitivity, temperament
|
|
|
Scoring system for sputum evaluation assessing specificity and sensitivity
Fidra, Dominika ; Trnková, Ivana (advisor) ; Maláska, Jan (referee)
The aim of this diploma thesis is to create a scoring system in sputum evaluation for general nurses in the intensive care unit. It is conceived as a diagnostic study that assesses the ability of the scoring system to accurately determine the ongoing condition - an infectious inflammatory disease. The collected biological material was compared with the gold standard - microbiology, by two independent persons. The result of the diagnostic study is a verified scoring system, where the color, consistency, admixtures and odor of the biological material of sputum are described for individual point evaluations. The main parameters of the diagnostic test - sensitivity, specificity and predictive value (positive and negative) - were used to verify the scoring system. For normal and pathological values, cut-off values were determined, according to which the value of sensitivity and specificity changed. By plotting the values on a graph and creating a ROC curve, it was found that with a cut off value of 1 and 2 for the first evaluator, the resulting area under the curve (AUC)=0.75. The result represents the scoring system according to the first evaluator as a good and effective test. The research was carried out at the anesthesiology and resuscitation clinic at the University Hospital of Kralovske Vinohrady...
|
|
| |
|
|
Image fusion within prostate biopsy
ŽŮČEK, David
This study deals with the use of image fusion within prostate biopsy, which is a method used for several decades, which serves to accurately capture pathological findings in the prostate, primarily prostate cancer. The combination of imaging modalities, which are magnetic resonance and intracavitary ultrasonography, is used to guide the biopsy. The aim of the study was to study the unusual situation where one and the same radiological team performs both procedures at the same time. Procedures from which the prostate biopsy methodology guided by image fusion is formed. Subsequently, we established a hypothesis that specific benefits can be found when the same doctor and radiology assistant perform both procedures. Procedures which consists of image fusion of magnetic resonance imaging and intracavitary ultrasonography, which guide the prostate biopsy of the same patient. The methodology of the theoretical part was the study of mostly foreign professional medical articles and literature and the subsequent use of the information to clarify the described method. In the practical part, the output data of physical examination of 59 patients were processed with the use of ROC analysis and then compared with two foreign studies to verify the established hypothesis. The data were provided by Mr. MUDr. Zdeněk Chudáček Ph.D. The results of the ROC analysis and its comparison with foreign studies confirmed the hypothesis, and therefore the presence of specific advantages of the studied unusual situation of performing a prostate biopsy in the way determined at the beginning of this study. The results of this study will be used in a broader journal publication, which aims to bring the issue of this study to the professional radiological public.
|
guest ::
