Dissertations / Theses on the topic 'Heart Rate Variability (HRV) Signals'
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Alghoul, Karim. "Heart Rate Variability Extraction from Video Signals." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33003.
Full textSoler, Anderson Ivan Rincon. "Impact of artifact correction methods on R-R interbeat signals to quantifying heart rate variability (HRV) according to linear and nonlinear methods." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/59/59135/tde-02052016-130306/.
Full textNa análise da variabilidade da frequência cardíaca (Heart Rate Variability - HRV) são usadas séries temporais que contém as distancias entre batimentos cardíacos sucessivos, com o m de avaliar a regulação autonômica do sistema cardiovascular. Estas séries são obtidas a partir da análise de sinais de eletrocardiograma (ECG), as quais podem ser afetados por distintos tipos de artefatos, levando a interpretações incorretas nas análises feitas sob as séries da HRV. Abordagem clássica para lidar com esses artefatos implica a utilização de métodos de correção, alguns deles com base na interpolação, substituição ou técnicas estatísticas. No entanto, existem poucos estudos que mostram a precisão e desempenho destes métodos de correção em sinais reais da HRV. Assim, o presente estudo tem como objetivo determinar cómo os diferentes níveis de artefatos presentes no sinal afetam as caraterísticas da mesma, utilizando-se diferentes métodos lineares e não lineares de correção e posteriormente quanticação dos parâmetros da HRV. Como parte da metodología utilizada, sinais ECG de ratos obtidas mediante a técnica da telemetria foram usadas para gerar séries de HRV reais sem nenhum tipo de erro. Nestas séries foram simulados batimentos perdidos para diferentes taxas de pontos a m de emular a situação real com a maior precisão possível. Adicionalmente, foram aplicados os métodos de eliminação de segmentos (DEL), interpolação linear (LI) e cúbica (CI), janela de média móvel (MAW) e interpolação preditiva não lineal (NPI) como métodos de correção dos artefatos simulados sob as séries com erros. A precisão de cada método de correção foi conhecida através dos resultados obtidos com a quanticação do valor médio da série (AVNN), desvio padrão (SDNN), erro quadrático médio das diferenças entre batimentos sucessivos (RMSSD), periodograma de Lomb (LSP), análise de flutuações destendenciadas (DFA), entropia multiescala (MSE) e dinâmica simbólica (SD) sob cada sinal de HRV com e sem erros. Os resultados obtidos mostram que para baixos níveis de perdas de batimentos o desempenho das técnicas de correção é similar, com valores muito semelhantes para cada parámetro quanticado da HRV. Não obstante, em níveis de perdas maiores só NPI permite obter valores muito próximos e sem muitas diferenças signicativas para os mesmos parâmetros da HRV, em comparação com os valores calculados para as séries sem perdas.
Wang, Yuan. "Heart rate variability and respiration signals as late onset sepsis diagnostic tools in neonatal intensive care units." Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S106/document.
Full textLate-onset sepsis, defined as a systemic infection in neonates older than 3 days, occurs in approximately 10% of all neonates and in more than 25% of very low birth weight infants who are hospitalized in Neonatal Intensive Care Units (NICU). Recurrent and severe spontaneous apneas and bradycardias (AB) is one of the major clinical early indicators of systemic infection in the premature infant. Various hematological and biochemical markers have been evaluated for this indication but they are invasive procedures that cannot be repeated several times. The objective of this Ph.D dissertation was to determine if heart rate variability (HRV), respiration and the analysis of their relationships help to the diagnosis of infection in premature infants via non-invasive ways in NICU. Therefore, we carried out Mono-Channel (MC) and Bi-Channel (BC) Analysis in two selected groups of premature infants: sepsis (S) vs. non-sepsis (NS). (1) Firstly, we studied the RR series not only by distribution methods (moy, varn, skew, kurt, med, SpAs), by linear methods: time domain (SD, RMSSD) and frequency domain (p_VLF, p_LF, p_HF), but also by non-linear methods: chaos theory (alphaS, alphaF) and information theory (AppEn, SamEn, PermEn, Regul). For each method, we attempt three sizes of window 1024/2048/4096, and then compare these methods in order to find the optimal ways to distinguish S from NS. The results show that alphaS, alphaF and SamEn are optimal parameters to recognize sepsis from the diagnosis of late neonatal infection in premature infants with unusual and recurrent AB. (2) The question about the functional coupling of HRV and nasal respiration is addressed. Linear and non-linear relationships have been explored. Linear indexes were correlation (r²), coherence function (Cohere) and time-frequency index (r2t,f), while a non-linear regression coefficient (h²) was used to analyze non-linear relationships. We calculated two directions during evaluate the index h2 of non-linear regression. Finally, from the entire analysis process, it is obvious that the three indexes (r2tf_rn_raw_0p2_0p4, h2_rn_raw and h2_nr_raw) were complementary ways to diagnosticate sepsis in a non-invasive way, in such delicate patients.(3) Furthermore, feasibility study is carried out on the candidate parameters selected from MC and BC respectively. We discovered that the proposed test based on optimal fusion of 6 features shows good performance with the largest Area Under Curves (AUC) and the least Probability of False Alarm (PFA). As a conclusion, we believe that the selected measures from MC and BC signal analysis have a good repeatability and accuracy to test for the diagnosis of sepsis via non-invasive NICU monitoring system, which can reliably confirm or refute the diagnosis of infection at an early stage
Franěk, Pavel. "Analýza variability srdečního rytmu pomocí rekurentního diagramu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220048.
Full textJohnston, William S. "Development of a signal processing library for extraction of SpO2, HR, HRV, and RR from photoplethysmographic waveforms." Worcester, Mass. Worcester Polytechnic Institute, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-073106-130906/.
Full textKeywords: wearable medical sensors; arterial oxygen saturation; software development; embedded systems; heart rate; respiration rate; heart rate variability; pulse oximetry; digital signal processing Includes bibliographical references (leaves 125-133).
Jež, Radek. "Software pro ruční rozměření signálů EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219251.
Full textHeathers, James. "Methodological improvements in heart rate variability." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/13106.
Full textBoman, Kajsa. "Heart rate variability : A possible measure of subjective wellbeing?" Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-15911.
Full textSuh, Sooyeon. "STRESS, ANXIETY, AND HEART RATE VARIABILITY IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275495558.
Full textMinnis, James Michael. "Nutrition and athletic performance: implications of heart rate variability." Kansas State University, 2015. http://hdl.handle.net/2097/20344.
Full textDepartment of Human Nutrition
Mark Haub
The purpose of this review is to examine the role of heart rate variability (HRV) as a predictor of athletic readiness and performance and assess whether nutrition strategies can be implemented to create favorable HRV indices with the goal of improving athletic readiness and performance. The balance between training and recovery is crucial for reaching an optimal adaptation and avoiding overtraining, allowing for improved readiness to train and compete. The measurement of HRV is non-invasive and is used primarily to quantify physical and mental stress in athletes by monitoring the effects of the autonomic nervous system on the heart. Current data suggests a relationship between resting parasympathetic tone, via time and frequency domains, and athletic performance. Parasympathetic modulated HRV indices have been associated with performance metrics such as peripheral work capacity, aerobic power, running and sprint performance, swimming performance, weight lifting performance, anaerobic capacity, strength, and enhanced mental focus/skill execution. The use of nutrition to help enhance sports performance is becoming more common. Evidence-based sports nutrition provides fuel for training/competition, assists in maximizing training adaptations, enhances recovery, improves mental focus, and aids in injury prevention and recovery. The use of nutrition strategies to influence HRV is novel and current evidence is scarce in regards to nutritional effects on HRV, specifically in athletes. Current research suggests that achieving energy balance and decreasing body fat in overweight/obese individuals has positive effects on the vagal component of HRV indices. Proper hydration, fruit and vegetable intake, a moderate carbohydrate diet, omega-3 fatty acid supplementation/intake also seem to have positive effects on HRV indices. Certain individual supplements have been studied in regards to HRV including casein hydrolysate, amaranth oil, and bovine colostrum. Caffeine seems to have the opposite effect on HRV indices, increasing sympathetic modulation while decreasing parasympathetic modulation. Much more research needs to be done in regard to potential nutritional influences on HRV so that sport dietitians feel confident in the methods currently used to assess athlete readiness and determining what types of nutrition strategies may be used to further improve the performance of an athlete.
Free, Matthew Lee. "Heart Rate Variability at Rest and During Worry in Chronic Worriers." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555597778352683.
Full textLedoux, Thomas M. "The Role of Heart Rate Variability in the Treatment of Migraines." Antioch University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1427823107.
Full textJoseph, Nicholas Patrick Joseph. "An Examination of the Association between Heart Rate Variability, Anxiety, and The Need for Affect." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1537810169788763.
Full textShafer, Lauren Marie. "Low-Impact Yoga Improves Flexibility, but Has No Effect on Heart Rate Variability in Sedentary Adult Women." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1535410337213529.
Full textCaha, Martin. "Klasifikace EKG na základě metod HRV analýzy." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220051.
Full textLanglois, Carolyn M. "Levels of Emotional Awareness: A psychophysiological investigation." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1253561949.
Full textHu, Dixie Doreen. "Forgiveness from the Heart: A Psychophysiological Study." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471276252.
Full textMadison, Annelise Alissa. "Social Anxiety Symptoms, Heart Rate Variability, and Vocal Emotion Recognition: Evidence of a Normative Vagally-Mediated Positivity Bias in Women." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu15582676377176.
Full textEllis, Robert J. "The effect of musical tempo on subjective and physiological indices of affective response." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250634561.
Full textPiedmont, Joanna I. "Examining Generalized Anxiety Disorder During Social Interactions: Cardiac Activity, and the Influence of Affect." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449839541.
Full textSpeller, Lassiter F. "The Effects of Training and Individual Differences in Heart Rate Variability on the Golf Swing’s Coordination Structure." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345224279.
Full textČíhal, Martin. "Analýza variability srdečního rytmu pomocí fraktální dimenze." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220052.
Full textSpielmann, Nadine. "Heart rate variability in relation to the menstrual cycle in trained and untrained women." Doctoral thesis, Humboldt-Universität zu Berlin, Philosophische Fakultät IV, 2005. http://dx.doi.org/10.18452/15169.
Full textIntroduction: The autonomic control of the heart is assumed to be affected by endogenous hormonal fluctuations in normal ovulatory females. Analyzing heart rate variability (HRV) had become a tool for the noninvasive measurement of cardiac autonomic control. The purpose of the present study was to investigate the course of the HRV parameters in moderately active as well as in long time endurance trained women during the menstrual cycle. Methods: Normal ovulatory females, untrained and trained were enrolled. Female athletes were involved in individually different training patterns (>5h/week) during the study. HRV recordings were obtained during five different menstrual cycle phases: menstruation (M), middle of follicular (MidF), ovulation (O), middle of luteal (MidL) and pre menstruation phase (PreM). Phases were verified by basal body temperature and analysis of luteinizing hormone (LH), follicular stimulation hormone (FSH), β-17 estrogen (E2) and progesterone (P). HRV measurements took place at subjects’ spontaneous breathing frequency in supine position (20 min) as well as during an orthostatic test. Parameters of short-term recording were calculated in time and frequency domain. Results: All women had normal ovulatory menstrual cycles including typical endogenous hormonal fluctuations; levels of LH, FSH, E2 and P were significantly different (p
Čukić, Iva. "Personality traits and health outcomes : an exploration into associations and potential mechanisms." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/16170.
Full textHerbell, Kayla. "Social Determinants of Health and Psychophysiological Stress in Pregnant Women: Correlates with Maternal Mental Health." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1534160752855093.
Full textZaturenskaya, Mariya. "The Role of Mindfulness in Cardiovascular Recovery from Stress." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1563462730045067.
Full textVykoupil, Pavel. "Použití analýzy HRV pro automatickou detekci ischemie u izolovaného zvířecího srdce." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220564.
Full textPenzlin, Ana Isabel, Kristian Barlinn, Ben Min-Woo Illigens, Kerstin Weidner, Martin Siepmann, and Timo Siepmann. "Effect of short-term heart rate variability biofeedback on long-term abstinence in alcohol dependent patients – a one-year follow-up." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-230932.
Full textHuang, Lin. "Effects of aromatherapy on negative emotions and work and study performance: heart rate variability analysis to assess the balance of the autonomic nervous system." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/402260.
Full textThe general aim of this thesis is to analyse the aromatherapy (AR) efficacy to reduce negative emotions and increase the attention level and performance in the workplace and in academic situations. Its efficacy will be tested through questionnaires and by checking the balance of the Autonomic Nervous System through HRV analysis. To carry out this general objective, we conducted two main studies. We will analyse the AR effects over the heart rate variability (HRV) as a marker of the sympathetic/parasympathetic balance from the ANS. The objective for Study 1 was to analyse the AR efficacy for reducing anxiety and improving study concentration in university students. The sample was composed by 12 students (age between 18 and 33 years old). We analysed the effects of basil essential oil inhalation at short-‐time (1 hour) and at long-‐time (1 month). We found that Inhalation of Basil essential oil reduces anxiety scoring and improves cardiac variability (SDRR and RMSSD parameters). AR in a short session or with an aromatic necklace every day during one month produces emotional and HRV changes on participants. The objective for Study 2 was to analyse the aromatherapy efficacy to improve the work performance and reduce the workplace stress. The sample was composed by 42 administrative university workers (age: 42.21 years, SD=7.12; gender: 10 men and 32 women). All sessions were performed in a university computer classroom. The participants were randomly assigned into an aromatherapy group (AG) and a control group (CG), and they were invited to participate in a specific session only once. They were seated in front of a computer. During the intervention period, some oil diffusers were launched and worked throughout the session with petit grain essential oil for AG sessions and a neutral oil (almond) for CG sessions. At the same time, participants completed a computer task in a specific website typing on their keyboard until they finished it. The single times were different for all participants and were recorded in the website as “Performance Time”. The aromatherapy group performed the website task with the keyboard 2, 28 min faster than CG typing (p=0.05) and showed better cardiac variability (HF, SDNN and RMSSD parameters). Inhalation of Petitgrain essential oil reduces stress and improves performance in the workplace. AR improves the performance time when typing with the keyboard in a simulated computer work session and produces some changes improving HRV. General Conclusions: This doctoral thesis confirms that aromatherapy (inhaling essential oils) can improve performance in the workplace, can help to manage negative emotions and can increment attention level in academic and workplace situations. Our results confirm that inhalation of essential oils produces this effect by balancing the sympathetic/parasympathetic system of the Autonomic Nervous System. HRV analysis is a good marker of this effect. This ANS balance can be explained by a combined action of the Petitgrain and Basil main components. Some of them have sedative effects, which can induce changes on the parasympathetic activity, and other components have activation effects, which stimulate the sympathetic activity. The final effect can be an improvement of the mental and emotional condition by a combination of reducing stress level and increasing arousal level of the participants in terms of attentiveness and alertness. We can also explain our results according to TCM. Essential oils can work through a truly holistic therapy, taking into account the mind, the body and the spirit of the person. Essential oils can connect with our body and help it to find the best way to solve its needs. The relaxing effects (parasympathetic activity) can be related to YIN and the activation effects (sympathetic activity) can be related to YANG.
Nytorpe, Piledahl Staffan, and Daniel Dahlberg. "Detektering av stress från biometrisk data i realtid." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-31248.
Full textJohansson, Amanda. "Idiopathic environmental intolerance attributed to electromagnetic fields : physiological and psychological aspects." Doctoral thesis, Umeå universitet, Yrkes- och miljömedicin, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1886.
Full textPadin, Avelina C. "Implicit attitudes, physical activity and self-regulatory capacity." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1467813684.
Full textShi, Ping. "Photoplethysmography in noninvasive cardiovascular assessment." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/5399.
Full textGunzenhauser, Jan. "Application of real-time HRV biofeedback in the scenario of meditation practice : Feasibility, usability and medical fidelity." Thesis, Linnéuniversitetet, Institutionen för medieteknik (ME), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-45420.
Full textMoreno, Sánchez Jordi. "Esport, salut i HRV: monitorització psicofisiològica de l’estrès i la recuperació amb dispositius mòbils." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/298302.
Full textThe risk of developing overtraining syndrome is a factor to be taken into account in preparing sport. In this sense, proper recovery is crucial to ensure a functional adaptation of the athlete in training and competitions. Continuous assessment of recovery from a psychophysiological perspective can provide information about the actual state of the athlete, but require tools and methodologies that allow to monitor the recovery with fast, in real-time and non-invasive in the natural environment of the athlete. In this context, the two main objectives of this thesis are: 1) Analyse the usefulness of seismocardiography (SCG) and photoplethysmography (PPG) for the analysis of HRV; and 2) Propose the psychophysiological monitoring of the stress and recovery process as a tool of Ecological Momentary Assessment (EMA) in sport situations, from the combined analysis of HRV and cognitive and behavioural indicators. In this Doctoral Thesis has been performed six studies, three related with innovation methodology for analysis of HRV, and three more related with the application of the analysis of HRV in the sport context. In the first part of the thesis, we propose techniques SCG and PPG as a valid to estimate of RR intervals and subsequent analysis of HRV. In the case of the use of the SCG, the results show that is necessary a stringent conditions of record in supine position, total rest and the importance to customize the placement of the device on the sternum of the person to improve the quality signal. SCG signal of iPhone is an effective technique for remote monitoring of the athlete without additional accessory. In the case of facial PPG, the results show that the supine position is more optimal than the sitting position. Although the registration conditions are too strict as for use in a sport context can be effective in natural contexts of hospital for monitoring patients in a controlled environment. In the second part of the thesis proposes HRV analysis for the determination of specific profiles depending on the sport. This methodology could help to determine the predisposition of the athlete to a sport modality or to evaluate the adaptation of the athlete compared to other colleagues who follow the same training plan. The combined analysis of HRV with the mood in a timely evaluation is useful for detecting states of Vigour or Fatigue, but not enough to detect profiles of Tension, Depression or Hostility. Also proposed the use of EMA as a useful methodology for detecting psychophysiological profiles of recovery, suggesting the need to analyse and interpret the HRV parameters individually instead of using scales population. In the case of breathing, the results indicate that the protocol used in the data collection (spontaneous or paced breathing) directly influences the values of the parameters of frequency domain, causing bias in the interpretation of the state of stress-recovery assessed with questionnaires. In this sense, the results show that spontaneous breathing provides relevant information about the state of stress of the athlete. From the results obtained in this thesis, we propose the use of smartphones to analyse HRV, mood and behavioural aspects relating to the recovery or lifestyles, according to a model of EMA and to a non-invasive technology thanks to the integrated sensors themselves. The resulting system, applied to the sports field, allows monitoring of psychophysiological stress-recovery process.
Smith, Brianna. "Assessing the relationship between resting autonomic nervous system functioning, social anxiety, and emotional autobiographical memory retrieval." Thesis, Boston College, 2018. http://hdl.handle.net/2345/bc-ir:108097.
Full textIndividuals with social anxiety disorder (SAD) tend to have emotional memory biases in the encoding and retrieval of social memories. Research has shown reduced heart rate variability (HRV) in clinical populations suffering from anxiety, including social anxiety. Heightened sympathetic activation—as measured by the electrodermal activity (EDA)—has also been associated with anxiety disorders. The aim of the present study was to examine the relation between HRV, social anxiety, and re-experiencing of emotional autobiographical memories. 44 healthy young adults were recruited from the Boston College campus through SONA. Participants were given an online survey that instructed them to retrieve 40 specific events from the past in response to 40 socially relevant cues. For each event, participants were instructed to provide a brief narrative, make several ratings for the event (on a scale from 1-7), and indicate the specific emotions they experienced both at the time of retrieval and of the event. Approximately one month after the completion of the memory survey, participants engaged in a 2-hour memory retrieval session while undergoing psychophysiological monitoring (heart rate, skin conductance, and respiration). Following the retrieval task, participants completed self-report questionnaires of social anxiety symptom severity and trait emotion regulation strategy (i.e., tendency to reappraise or suppress emotions). The present study found that positive memories had higher re-experiencing ratings as compared to negative memories. Contrary to the original study hypothesis, however, there was no significant interaction between average re-experiencing (or arousal) ratings of positive or negative social autobiographical memories and SAD likelihood. A nonlinear, cubic relationship was found between one of three metrics of HRV and social anxiety symptom severity. A significant effect was found between skin conductance and SAD likelihood, which was likely driven by an almost significance difference in skin conductance between the SAD unlikely and the SAD very probable groups; these findings provide further insight into the relationship between autonomic nervous system (ANS) functioning and social anxiety. Further, the present results suggest the intriguing possibility that there may be a nonlinear relationship between HRV and severity of social anxiety. Future research with a larger sample size is needed to corroborate these findings
Thesis (BS) — Boston College, 2018
Submitted to: Boston College. College of Arts and Sciences
Discipline: Departmental Honors
Discipline: Psychology
Dizon, Lucas, and Martin Johansson. "Atrial Fibrillation Detection Algorithm Evaluation and Implementation in Java." Thesis, KTH, Skolan för teknik och hälsa (STH), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-158878.
Full textFörmaksflimmer är en vanlig hjärtrytmrubbning som kännetecknas av en avsaknad eller oregelbunden kontraktion av förmaken. Sjukdomen är en riskfaktor för andra allvarligare sjukdomar och de totala kostnaderna för samhället är betydande. Det skulle därför vara fördelaktigt att effektivisera och förbättra prevention samt diagnostisering av förmaksflimmer. Kliniskt diagnostiseras förmaksflimmer med hjälp av till exempel pulspalpation och auskultation av hjärtat, men diagnosen brukar fastställas med en EKG-undersökning. Det finns idag flertalet algoritmer för att detektera arytmin genom att analysera ett EKG. En av de vanligaste metoderna är att undersöka variabiliteten av hjärtrytmen (HRV) och utföra olika sorters statistiska beräkningar som kan upptäcka episoder av förmaksflimmer som avviker från en normal sinusrytm. I detta projekt har två metoder för att detektera förmaksflimmer utvärderats i Matlab, en baseras på beräkningar av variationskoefficienten och den andra använder sig av logistisk regression. EKG som kommer från databasen Physionet MIT används för att träna och testa modeller av algoritmerna. Innan EKG-signalen kan användas måste den behandlas för att ta bort olika typer av brus och artefakter. Vid test av algoritmen med variationskoefficienten blev resultatet en sensitivitet på 91,38%, en specificitet på 93,93% och en noggrannhet på 92,92%. För logistisk regression blev sensitiviteten 97,23%, specificiteten 93,79% och noggrannheten 95,39%. Algoritmen med logistisk regression presterade bättre och valdes därför för att implementeras i Java, där uppnåddes en sensitivitet på 91,31%, en specificitet på 93,47% och en noggrannhet på 95,25%.
Bonomi, Mattia. "Facial-based Analysis Tools: Engagement Measurements and Forensics Applications." Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/271342.
Full textBonomi, Mattia. "Facial-based Analysis Tools: Engagement Measurements and Forensics Applications." Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/271342.
Full textTiinanen, S. (Suvi). "Methods for assessment of autonomic nervous system activity from cardiorespiratory signals." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526223131.
Full textTiivistelmä Autonominen hermosto säätelee tarkasti sydän- ja verenkiertoelimistöä sekä hengitystä. Autonomisen hermoston toimintaa voidaan analysoida laskennallisin menetelmin noninvasiivisesti mitatuista elektrokardiogrammi- (EKG, sydänsähkökäyrä), verenpaine- ja hengityssignaaleista. Useita tekijöitä ja sairauksia voidaan yhdistää autonomisen hermoston epätasapainoon. Väitöskirjassa kehitettiin menetelmiä sydän- ja verisuonijärjestelmän autonomisen säätelyn kuvaamiseksi lyhytaikaisista kardiorespiratorisista tallenteista. Erityistä huomiota on kiinnitetty hengityksen vaikutukseen perinteisiin taajuustasosta laskettaviin muuttujiin, jotka kuvaavat autonomisen hermoston toimintaa. Väitöskirjan päätuloksia ja -tuotoksia ovat: 1) uusi adaptiiviseen suodatukseen pohjautuva laskennallinen menetelmä hengitysvaikutuksien poistamiseksi sydän- ja verisuonisignaaleista. Adaptiivinen suodatin vähensi matalan hengitystaajuuden aiheuttamaa vääristymää hermoston toimintaa kuvaavista parametreistä. Uusi menetelmä mahdollistaa kontrolloimattoman eli vapaan hengitystaajuus-protokollan käytön autonomisen hermoston toiminnan mittauksissa. 2) Uusia menetelmiä respiratorisen sinus arrytmian (RSA) määrittämiseksi sydän- ja verisuonisignaaleista. Kehitetyissä menetelmistä kahdessa käytetään adaptiivista suodatusta hyödyntäen joko mitattua hengityssignaalia tai EKG:stä johdettua hengityssignaalia. Kolmas menetelmä pohjautuu itsenäisten komponenttien analyysiin. Kehitetyt menetelmät RSA:n laskemiseksi sallivat hengitystaajuuden vaihtelun mittauksien aikana, mikä tekee ne fysiologisesti tarkemmaksi kuin perinteisesti käytetty korkeataajuinen (HF) komponentti, joka lasketaan taajuustasossa tietyltä kaistalta riippumatta hengitystaajuudesta. 3) Kehitettiin ja sovellettiin menetelmiä EKG:n ja verenpaineen matalataajuisten (LF) heilahtelujen tutkimista varten. Yhdessä tutkimuksessa sovellettiin aika-taajuustason esitystapaa vaihtelevan datan analysoimiksi. Kokeellinen tutkimus tehtiin aineistolla, joka oli jatkumo sydän- ja verisuonitautien riskejä omaavista potilaista jo sairastuneisiin potilaisiin. Ikääntyminen pienensi matalataajuisen heilahtelun taajuutta ja sepelvaltimosairaus pienensi sitä edelleen. 4) Kaksi uutta hajotelmatekniikoita hyödyntävää menetelmää, joilla lasketaan EKG:stä hengitysvirtausignaali-estimaatti (EDR). Kehitettyjen EDR-menetelmien suorituskyky osoittautui tilastollisesti paremmaksi kuin aikaisemmat menetelmät. Koska hengityssignaali ja -taajuus voidaan johtaa suoraan EKG:stä, tarvittavien mittaussensoreiden määrää vähenee. Lisäksi EDR:ää voidaan hyödyttää autonomisen hermoston toimintaa kuvaavien parametrien estimoinnissa. Väitöskirja tarjoaa menetelmiä autonomisen hermoston toiminnan mittaamiseksi huomioiden erityisesti hengityksen vaikutus estimoitaviin parametreihin. Väitöskirjan tuloksia voidaan soveltaa useissa kardiorespiratorisia signaaleja hyödyntävissä sovelluksissa aina kliinisestä työstä fysiologian tutkimukseen ja kaupallisiin hyvinvointi-, terveys- ja urheilusovelluksiin
Huomautus/Notice Painetussa virheellinen ISBN: 978-952-62-2312-4, oikea 978-952-62-2310-0. Printed version has incorrect ISBN: 978-952-62-2312-4, it should be 978-952-62-2310-0
Cassirame, Johan. "Intérêts et limites de l'utilisation de l'analyse de la variabilité de la fréquence cardiaque pour la pratique sportive." Thesis, Besançon, 2015. http://www.theses.fr/2015BESA3001/document.
Full textHeart Rate Variability Analysis is a non-invasive method for the evaluation of the Autonomic Nervous System activity. This analytical method initially used for clinical diagnosis progressively installed in the field of physical activity for various applications such as early detection of overreaching, calibration of training intensity, ventilatory threshold determination... These methods can be used outside the laboratory environment, but still require particular attention from a methodological aspect in order to be consistent with mathematical or physiological concepts underlying. Each step of this method requires a specific discipline not to lead to misinterpretation. This document details the process from the RR interval measurement phase including accuracy assessment of the devices used in the field or signal treatment with artifacts correction proposing several methods. This work details index from HRV analysis with their technical and conceptual limitations. External factors mat influence the Autonomic Nervous System are described to facilitate the protocol creation and results interpretation
Benešová, Lenka. "Vyhodnocení variability rychlosti pulzové vlny." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400981.
Full textRöstin, Martin. "Development of a Flexible Software Framework for Biosignal PI : An Open-Source Biosignal Acquisition and Processing System." Thesis, KTH, Skolan för teknik och hälsa (STH), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183525.
Full textAllt eftersom världens befolkning åldras, ställs sjukvården inför nya utmaningar i att behandla fler patienter till en lägre kostnad än idag. En trend för att lösa detta problem är att utöka möjligheterna till vård i hemmet.För att kunna göra detta finns det ett ökande behov av säkra och kostnadseffektiva patientövervakningssystem. Biosignal PI är ett pågående projekt med öppen källkod som skapats för att utveckla en flexibel och prisvärd plattform för utveckling av fristående enheter som kan mäta och bearbeta olika fysiologiska signaler. Detta examensarbete genomfördes vid institutionen för medicinska sensorer, signaler och system vid Skolan för Teknik och Hälsa. Projektet syftade till att vidareutveckla den befintliga mjukvaran för Biosignal PI genom att skapa ett nytt flexibelt mjukvaruramverk som kan användas för mätning och bearbetning av olika typer av biosignaler.Projektet syftade också till att utvidga mjukvaran och lägga till funktioner för att kunna genomföra hjärtfrekvensvariabilitets(HRV) analys i Biosignal PIs mjukvara, samt att utveckla ett grafiskt användargränssnitt(GUI) för hårdvarumodulen PiFace Control and Display. Projektet har utvecklat ett nytt flexibelt mjukvaruramverk för Biosignal PI. Det nya ramverket konstruerades för att abstrahera alla hårdvaruspecifika delar in i mindre utbytbara moduler, med tanken att modulerna ska vara oberoende i hur de hanterar sin specifika uppgift. På så sätt ska det vara möjligt att göra ändringar i Biosignal PIs programvara utan att behöva skriva om hela mjukvaran.Det nyutvecklade Biosignal PI ramverket implementerades i det befintliga hårdvaru systemet, som består av en Raspberry PI, liten och prisvärd enkortsdator, ansluten till ADAS1000, en analog hårdvarumodul med möjlighet att registrera ett elektrokardiografi(EKG/ECG). För att kontrollera Biosignal PI programmet har två olika grafiska användargränssnitt skapats.Det ena gränssnitt är en utvidgning av original programvaran med tillagd funktionalitet för att kunna göra HRV-Analys på Raspberry PI, detta gränssnitt kräver dock mus och dataskärm för att kunna användas.För att kunna styra Biosignal PI utan mus och skärm skapades det även ett gränssnitt för PiFace Control and Display. PiFace gränssnittet gör det möjligt för användaren att samla in och lagra EKG-signaler utan att behöva en stor datorskärm, på så sätt kan man öka Biosignal PI systemets mobilitet. För att underlätta utvecklingsprocessen, samt göra projektet mer förenligt med det medicintekniska regelverket, har ett par utvecklingsverktyg integrerats till Biosignal PI projektet såsom CMake för kontroll av kompileringsprocessen, test ramverket Googletest för automatiserad testning samt integrering med dokumentations generatorn Doxygen för att kunna skapa en dokumentation av mjukvaran.
Doyen, Matthieu. "Méthodes probabilistes pour le monitoring cardio-respiratoire des nouveau-nés prématurés." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S049/document.
Full textThe surveillance of premature newborns placed in intensive care units led to the notion of monitoring and the acquisition of many physiological signals. While this information is well used for the diagnosis and prevention of emergency situations, it must be acknowledged that, to date, it is less the case for predictive purposes. This is mainly due to the difficulty of extracting reliable information in real time, without any visual control, from non-stationary signals. This thesis aims to propose robust methods, adapted to the context of neonatal intensive care units and real time. For this purpose, a set of generic methods applied to cardiac variability, but capable of being adapted to other physiological constants such as respiration, have been developed and tested in clinical context. Four main parts illustrate these points : - The proposal of an original multicharacteristic probabilistic real time detection method for robust detection of interest events of noisy physiological signals. Generic, this solution is applied to the robust QRS complex detection of the ECG signals. It is based on the real time calculation of several posterior probabilities of the signal properties before merging them into a decision node using the weighted Kullback-Leibler divergence. Compared to two classic methods from the literature on two noisy databases, it has a lower detection error rate (20.91% vs. 29.02% (wavelets) and 33.08% (Pan-Tompkins) on the test database). - The proposal of using hidden semi-markovian models for the segmentation of temporal periods with most reliable event detections. Compared to two methods from the literature, the proposed solution achieves better performance, the error criterion obtained is significantly lower (between -21.37% and -74.98% depending on the basis and approach evaluated). - The selection of an optimal detector for the monitoring of apnea-bradycardia events, in terms of reliability and precocity, based on ECG data obtained from newborns. The performance of the selected detector will be compared to the alarms generated by an industrial continuous monitoring device traditionally used in neonatology service (Philips IntelliVue monitor). The method based on the abrupt change of the RR average achieves the best results in terms of time (3.99 s vs. 11.53 s for the IntelliVue monitor) and reliability (error criterion of 43.60% vs. 80.40%). - The design and development of SYNaPSE (SYstem for Noninvasive Physiological Signal Explorations) software platform for the acquisition of various physiological signals in large quantities, and in a non-invasive way, within the care units. The modular design of this platform, as well as its real time properties, allows simple and fast integration of complex signal processing methods. Its translational interest is shown in the analysis of a database in order to study the impact of bilirubin on cardiac variability
Silva, Luiz Eduardo Virgilio da. "Análise do sinal de variabilidade da frequência cardíaca através de estatística não extensiva: taxa de q-entropia multiescala." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/59/59135/tde-22032013-114045/.
Full textHuman body is a complex system composed of several interdependent subsystems, interacting at various scales. It is known that physiological complexity tends to decrease with disease and aging, reducing the adaptative capabilities of the individual. In the cardiovascular system, one way to evaluate its regulatory dynamics is through the analysis of heart rate variability (HRV). Classical methods of HRV analysis are based on linear models, such as spectral analysis. However, as the physiological mechanisms regulating heart rate exhibit nonlinear characteristics, analyzes using such models may be limited. In the last years, several proposals nonlinear methods have emerged. Nevertheless, no one is known to be consistent with the physiological complexity theory, where both periodic and random regimes are characterized as complexity loss. Based on physiological complexity theory, this thesis proposes new methods for nonlinear HRV series analysis. The methods are generalization of existing entropy measures, through Tsallis nonadditive statistical mechanics and surrogate data. We defined a method, called qSDiff, which calculates the difference between the entropy of a signal and its surrogate data average entropy. The entropy method used is a generalization of sample entropy (SampEn), through nonadditive paradigm. From qSDiff we extracted three attributes, which were evaluated as potential physiological complexity indexes. Multiscale entropy (MSE) was also generalized following nonadditive paradigm, and the same attributes were calculated at various scales. The methods were applied to real human and rats HRV series, as well as to a set of simulated signals, consisting of noises and maps, the latter in chaotic and periodic regimes. qSDiffmax attribute proved to be consistent for low scales while qmax and qzero attributes to larger scales, separating and ranking groups in terms of physiological complexity. There was also found a possible relationship between these q-attributes with the presence of chaos, which must be further investigated. The results also suggested the possibility that, in congestive heart failure, degradation occurs rather at small scales or short time mechanisms, while in atrial fibrillation, damage would extend to larger scales. The proposed entropy based measures are able to extract important information of HRV series, being more consistent with physiological complexity theory than SampEn (classical). Results strengthened the hypothesis that complexity is revealed at multiple scales. We believe that the proposed methods can contribute to HRV as well as to other biomedical signals analysis.
Schaffner, Markus. "Behavioural evidence for social preferences." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/48898/1/Markus_Schaffner_Thesis.pdf.
Full textClaesson, Maria. "Women's hearts : ischaemic heart disease and stress management in women." Doctoral thesis, Umeå : Department of Public Health and Clinical Medicine, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-725.
Full textEde, David E. Jr. "Trait Mindfulness and Cardiovascular Reactivity and Recovery During a Laboratory Mental Stress Protocol in Young Adults." Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent1524140223472705.
Full textDuque, Juliano Jinzenji. "Avaliação da q-transformada de Fourier como ferramenta não linear de estudos de sinais biomédicos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/59/59135/tde-29112012-121139/.
Full textBiomedical signals analysis is an important research eld because many physiological processes occurring in human body can have their activities recorded as signals.This study investigated the q-Fourier transform (q-FT), a nonlinear generalization of Fourier transform based on the Tsallis nonextensive formalism, which is characterized by q parameter. Analytical studies and computational experiments with simulated and real signals were conducted. From the denition of q-FT, a generalized spectral analysis method for application in biomedical signals has been developed. This method was assessed through experiments with cardiac RR interval time series, which are used in studies of heart rate variability. The results help to clarify some properties of the q-Fourier transform, but do not indicate that the developed method is efective for the spectral analysis of RR series. However, further studies on new spectral analysis methods based on Tsallis formalism can be developed for biomedical signals investigation.
Friberg, Annika. "Interaktionskvalitet - hur mäts det?" Thesis, Malmö högskola, Fakulteten för teknik och samhälle (TS), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20810.
Full textTechnical developments have led to the broadcasting of massive amounts of information, athigh velocities. We must learn to handle this flow. To maximize the benefits of newtechnologies and avoid the problems that this immense information flow brings, interactionquality should be studied. We must adjust interfaces to the user because the user does nothave the ability to adapt and sort overly large amounts of information. We must developsystems that make the human more efficient when using interfaces.To adjust the interfaces to the user needs and limitations, knowledge about humancognitive processes is required. When cognitive workload is studied it is important that aflexible, easily accessed and non assertive technique is used to get unbiased results. At thesame time reliability is of great importance. To design interfaces with high interaction quality,a technique to evaluate these is required. The aim of this paper is to establish a method that iswell suited for measurement of interaction quality.When measuring interaction quality, a combination of subjective and physiologicalmethods is recommended. This comprises a combination of Functional near-infraredspectroscopy; a physiological measurement which measures brain activity using light sourcesand detectors placed on the frontal lobe, Electrodermal activity; a physiological measurementwhich measures brain activity using electrodes placed over the scalp and NASA task loadindex; a subjective, multidimensional measurement based on card sorting and measures theindividual perceived cognitive workload on a continuum scale. Measuring with these methodscan result in an increase in interaction quality in interactive, physical and digital interfaces.An estimation of interaction quality can contribute to eliminate interaction errors, thusimproving the user’s interaction experience.