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.

This diploma thesis deals with location optimal wavelet for detecton charakterics points of QRS complex in ECG signals. The first part of this thesis deals with description of heart, genesis of electric signals on heart and problem of noise. The second part describes the wavelet transform and the designed program and the third part evaluate detection results. The created program is working with 10 ECG signals from the CSE database and is testing 12 different mother wavelets. The program was developed in Matlab environment and is based on the finding zero-points in the transformed signal.

This thesis deals with a proposition of an algorithm for QRS complex and typical ECG waves boundaries detection. It incorporates a literature research focused on heart electrophysiology and commonly used methods for ECG fiducial points detection and delineation. Out of the presented methods an algorithm based on a continuous wavelet transform is implemented. Detection and delineation algorithm is tested on CSE standard signal database towards references determined both manually and automatically. Obtained results are compared to other congenerous methods. The diploma thesis is further concerned with an algorithm modification for experimental electrocardiograms of isolated rabbit hearts. Recording specifics of these data are introduced. Additionally, based on time and frequency analysis, particular modifications of the algorithm are proposed and realized. Due to a large extent of records functionality is verified on randomly selected database samples. Efficiency of the modified algorithm is evaluated through manually annotated references.

This master's thesis deals with the optimization of numerical coefficients of the Wiener filter for muscle noise filtering in ECG signals. The theoretical part deals with ECG signal characteristic and muscle interference. It also contains a summary of the wavelet transform, wavelet Wiener's filtration, methods for calculating of the threshold and thresholding. In the last theoretical part the characteristic optimization techniques, the exhausive search and Nelder-Mead simplex method are mentioned, which were implemented in the practical part of this thesis in MATLAB. The functional verification and Wiener's filter optimization were tested on the standard electrocardiograms database CSE. By using the methods of exhausive search, the initial estimate for the solution method Nelder-Mead was obtained. The optimization method Nelder-Mead gives better results in the orders of hundredths or tenths than the method of exhausive search. The practical part is finished by the comparison of results of implemented algorithm with optimum coefficients, implemented in this thesis, with the results of other methods for filtering muscle interference in ECG signals.

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-06-29T12:10:42Z No. of bitstreams: 1 Daygles Maria De Souza Lima_.pdf: 4072480 bytes, checksum: 7d3039003678a4d4fd291ceb3ae3bfcf (MD5) / Made available in DSpace on 2017-06-29T12:10:42Z (GMT). No. of bitstreams: 1 Daygles Maria De Souza Lima_.pdf: 4072480 bytes, checksum: 7d3039003678a4d4fd291ceb3ae3bfcf (MD5) Previous issue date: 2017-03-30 / IFRR - Instituto Federal de Educação Ciência e Tecnologia de Roraima / A temática desta tese se articula com Juventude, identidade e violência na perspectiva dos socioeducandos em cumprimento de medida socioeducativa no CSE-RR por ato infracional de natureza grave. O objeto de estudo consiste, então, na percepção si e da violência, a partir da perspectiva e trajetória de vida dos socioeducandos em cumprimento de medida socioeducativa no CSE-RR por ato infracional de natureza grave. O objetivo geral é compreender a percepção do jovem sobre si, sobre os atos de violências na sua natureza mais grave e como são subjetivamente elaborados. Frente a este contexto, o universo empírico do qual esta pesquisa se ocupa é o jovem que cometeu ato infracional de natureza grave (conduta descrita como crime ou contravenção penal), mais especificamente latrocínio, estupro e homicídio qualificado, que está internado no Centro Socioeducativo Homero de Souza Cruz, respondendo medida socioeducativa com ou sem possibilidade de atividade externa. Para cumprir com o objetivo, optou-se de método qualitativo com viés antropológico e etnográfico por compreender que permitem uma abordagem naturalista, interpretativa do mundo circundante sob a ótica do outro. A seleção e coleta de dados se deu por análise de documentos, entrevistas e voluntariedade por parte dos participantes. Os instrumentos de coleta de dados utilizados foram entrevistas semiestruturadas, interações por meio da observação direta e de análise de documentos, por meio de roteiro semiestruturado, registro em diário de campo e análise de documentos. As categorias trabalhadas foram juventude, violência e identidade. Da teia de informações coletas e registradas em gravações e no diário de campo, foi possível interpretar e compreender os sentidos da violência cruel dos atos infracionais cometidos pelos jovens participantes, sob a lente de seus olhos. Da análise, resultou as concepções de violência, os sentidos da violência naturalizada na prática criminal e o sentido da violência cruel a partir da percepção do jovem interno do CSE-RR. / The subject matter of this thesis is articulated with Youth, Identity and Violence in the perspective of individuals participating in a social educational program under social educational measure in CSE-RR for an infraction of a serious nature. Therefore, the object of study is the perception of self and violence, based on the perspective and life trajectory of individuals participating in a social educational program under social educational measure in CSE-RR for an infraction of a serious nature. The general objective is to understand the young people’s perception of themselves when it comes to the acts of violence in their most serious nature and how they are subjectively elaborated. In the face of this context, the empirical universe of this research is the young person who committed a conduct described as crime or criminal contravention, more specifically robbery, rape and qualified homicide, who is interned at Homero de Souza Cruz Social-Educational Center, under social educational measure with or without the possibility of external activity. In order to comply with the objective, we chose a qualitative method with anthropological and ethnographic bias because we understand that they allow a naturalistic, interpretative approach to the surrounding world from the perspective of the other. The data selection and collection took place through the analysis of documents, interviews and willingness on the part of the participants. The instruments of data collection were semi-structured interviews, interactions through direct observation and document analysis, through semi-structured script, field journal and document analysis. The categories used were youth, violence and identity. From the web of information collected and recorded in recordings and in the field journal, it was possible to understand the meanings of the cruel violence related to the infractions committed by the young participants from their point of view. From the analysis, it is possible to access the notions of violence, the senses of the naturalized violence in the criminal practice and the sense of cruel violence from the perception of the young inmates in CSE-RR.

Various scales have previously been developed to measure coping strategies (Taylor & Stanton, 2007; Devonport & Lane, 2006; Stapelberg, 1999) or self–efficacy (Carroll et al., 2005; Chen et al., 2001; Tipton & Worthington, 1984); and some of them have been validated in a South African context, but the validation of a coping self–efficacy scale as a single measurement has not been conducted in an African context. Therefore, the aim of this study was to validate Chesney et al.’s 2006 Coping Self–Efficacy Scale (CSE) in an African context. A multicultural convenience sample of 2 214 South African adolescents and adults, including both male and female participants, participated in this study. Measuring instruments such as the Coping Self–Efficacy Scale (CSE) (Chesney, Neilands, Chambers, Taylor & Folkman, 2006), the Mental Health Continuum - Short Form for adults (MHC–SF) (Keyes et al., 2008), the New General Self–Efficacy Scale (NGSE) (Chen, Gully & Eden, 2001; 2004), the Fortitude Questionnaire (FORQ) (Pretorius, 1998), the Patient Health Questionnaire: Depression Symptoms (PHQ–9) (Kroenke, Spitzer & Williams, 2001) and the General Health Questionnaire (GHQ) (Goldberg & Hillier, 1979) were used in this study. Criterion–related validity of the CSE was established. Construct validity was determined by conducting confirmatory and exploratory factor analyses as well as SEM on the CSE. Results indicated a Cronbach alpha reliability coefficient of 0.87 and satisfactory inter–item correlations ranging from 0.19–0.21. Criterion–related validity was satisfactory. Confirmatory analysis indicated a good fit and exploratory factor analysis confirmed the three major factors similar to Chesney et al.’s (2006) findings. Construct validity was further supported by SEM analysis, which confirmed the three–factor structure. The CSE can be viewed as reliable and valid for use in further research in the African context. Future studies should validate this scale in various population groups, with translated versions of the scale and with randomly selected groups. / Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2011.

Various scales have previously been developed to measure coping strategies (Taylor & Stanton, 2007; Devonport & Lane, 2006; Stapelberg, 1999) or self–efficacy (Carroll et al., 2005; Chen et al., 2001; Tipton & Worthington, 1984); and some of them have been validated in a South African context, but the validation of a coping self–efficacy scale as a single measurement has not been conducted in an African context. Therefore, the aim of this study was to validate Chesney et al.’s 2006 Coping Self–Efficacy Scale (CSE) in an African context. A multicultural convenience sample of 2 214 South African adolescents and adults, including both male and female participants, participated in this study. Measuring instruments such as the Coping Self–Efficacy Scale (CSE) (Chesney, Neilands, Chambers, Taylor & Folkman, 2006), the Mental Health Continuum - Short Form for adults (MHC–SF) (Keyes et al., 2008), the New General Self–Efficacy Scale (NGSE) (Chen, Gully & Eden, 2001; 2004), the Fortitude Questionnaire (FORQ) (Pretorius, 1998), the Patient Health Questionnaire: Depression Symptoms (PHQ–9) (Kroenke, Spitzer & Williams, 2001) and the General Health Questionnaire (GHQ) (Goldberg & Hillier, 1979) were used in this study. Criterion–related validity of the CSE was established. Construct validity was determined by conducting confirmatory and exploratory factor analyses as well as SEM on the CSE. Results indicated a Cronbach alpha reliability coefficient of 0.87 and satisfactory inter–item correlations ranging from 0.19–0.21. Criterion–related validity was satisfactory. Confirmatory analysis indicated a good fit and exploratory factor analysis confirmed the three major factors similar to Chesney et al.’s (2006) findings. Construct validity was further supported by SEM analysis, which confirmed the three–factor structure. The CSE can be viewed as reliable and valid for use in further research in the African context. Future studies should validate this scale in various population groups, with translated versions of the scale and with randomly selected groups. / Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2011.

京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13378号 / 論医博第2212号 / 新制||医||1047(附属図書館) / (主査)教授 井上 治久, 教授 髙橋 良輔, 教授 渡邉 大 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

This master’s thesis deals with the detection of QRS complex detection using zero crossing counts. QRS detection is an important part of the analysis of ECG signal. From the point of determining the R wave detection is based on the other waves and intervals necessary for the diagnosis of heart. This method is very effective even for very noisy signals. Implementation of the method in Matlab, and the success of detection is tested on the CSE and MIT-BIH database. The optimization algorithm is an optional value for the detector.

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.