{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T14:17:37Z","timestamp":1766067457205,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,13]],"date-time":"2022-01-13T00:00:00Z","timestamp":1642032000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology","doi-asserted-by":"publisher","award":["110-2221-E-030 -001"],"award-info":[{"award-number":["110-2221-E-030 -001"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Due to the recent COVID-19 pandemic, many people have faced in-home isolation, as every suspected patient must stay at home. The behavior of such isolated people needs to be monitored to ensure that they are staying at home. Using a camera is a very practical method. However, smart bracelets are more convenient when personal privacy is a concern or when the blood oxygen value or heart rate must be monitored. In this study, a low-cost indoor positioning system that uses a Bluetooth beacon, a smart bracelet, and an embedded system is proposed. In addition to monitoring whether a person living alone is active in a specific environment and tracking the heart rate or blood oxygen value under particular conditions, this system can also send early warning signals to specific observation units or relatives through instant messaging software.<\/jats:p>","DOI":"10.3390\/s22020590","type":"journal-article","created":{"date-parts":[[2022,1,14]],"date-time":"2022-01-14T03:14:03Z","timestamp":1642130043000},"page":"590","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Design and Implementation of an Indoor Warning System with Physiological Signal Monitoring for People Isolated at Home"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6787-3517","authenticated-orcid":false,"given":"Chi-Huang","family":"Hung","sequence":"first","affiliation":[{"name":"Department of Information Technology, Lee-Ming Institute of Technology, New Taipei City 24346, Taiwan"},{"name":"Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 242062, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong-Yi","family":"Fanjiang","sequence":"additional","affiliation":[{"name":"Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 242062, Taiwan"},{"name":"Department of Computer Science and Information Engineering, Fu Jen Catholic University, New Taipei City 242062, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi-Shiune","family":"Lee","sequence":"additional","affiliation":[{"name":"Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 242062, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi-Chao","family":"Wu","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program of Green and Information Technology, National Taitung University, Taitung 95092, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Silapasuphakornwong, P., and Sookhanaphibarn, K. 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