{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,17]],"date-time":"2025-10-17T13:47:17Z","timestamp":1760708837307,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2015,5,14]],"date-time":"2015-05-14T00:00:00Z","timestamp":1431561600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2012R1A2A2A02010714"],"award-info":[{"award-number":["NRF-2012R1A2A2A02010714"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, we developed and tested a capacitively coupled electrocardiogram (ECG) measurement system using conductive textiles on a bed, for long-term healthcare monitoring. The system, which was designed to measure ECG in a bed with no constraints of sleep position and posture, included a foam layer to increase the contact region with the curvature of the body and a cover to ensure durability and easy installation. Nine healthy subjects participated in the experiment during polysomnography (PSG), and the heart rate (HR) coverage and heart rate variability (HRV) parameters were analyzed to evaluate the system. The experimental results showed that the mean of R-peak coverage was 98.0% (95.5%\u201399.7%), and the normalized errors of HRV time and spectral measures between the Ag\/AgCl system and our system ranged from 0.15% to 4.20%. The root mean square errors for inter-beat (RR) intervals and HR were 1.36 ms and 0.09 bpm, respectively. We also showed the potential of our developed system for rapid eye movement (REM) sleep and wake detection as well as for recording of abnormal states.<\/jats:p>","DOI":"10.3390\/s150511295","type":"journal-article","created":{"date-parts":[[2015,5,15]],"date-time":"2015-05-15T07:57:02Z","timestamp":1431676622000},"page":"11295-11311","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":53,"title":["Heart Rate Variability Monitoring during Sleep Based on Capacitively Coupled Textile Electrodes on a Bed"],"prefix":"10.3390","volume":"15","author":[{"given":"Hong Ji","family":"Lee","sequence":"first","affiliation":[{"name":"Interdisciplinary Program for Bioengineering, Graduate School, Seoul National University,  Seoul 110-799, Korea"}]},{"given":"Su Hwan","family":"Hwang","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program for Bioengineering, Graduate School, Seoul National University,  Seoul 110-799, Korea"}]},{"given":"Hee Nam","family":"Yoon","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program for Bioengineering, Graduate School, Seoul National University,  Seoul 110-799, Korea"}]},{"given":"Won Kyu","family":"Lee","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program for Bioengineering, Graduate School, Seoul National University,  Seoul 110-799, Korea"}]},{"given":"Kwang Suk","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, College of Medicine, Seoul National University,  Seoul 110-799, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2015,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"956","DOI":"10.1109\/TBME.2006.872823","article-title":"ECG measurement on a chair without conductive contact","volume":"53","author":"Lim","year":"2006","journal-title":"IEEE Trans. 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