{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T17:28:32Z","timestamp":1778347712191,"version":"3.51.4"},"reference-count":50,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,22]],"date-time":"2021-01-22T00:00:00Z","timestamp":1611273600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PKU-Baidu Fund","award":["2019BD005"],"award-info":[{"award-number":["2019BD005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>For a large population of elderly who live alone, a continuous long-term daily monitoring system is critical and imminently needed to enhance the quality of their lives. Continuous monitoring of vitality information (i.e., which area the elder is staying in, the motion state and activity intensity of an elder) is essential for elderly care. In this paper, we use existing commodity Wi-Fi devices to design and implement a long-term device-free human daily vitality system, WiMonitor. Our system can continuously capture the target\u2019s vitality information in a multi-room home environment without compromising the privacy of the target. In a continuous 22-day experiment, WiMonitor successfully captures the human vitality information accurately. We believe our system can provide valuable long-term monitoring data for both researchers and health care personnel.<\/jats:p>","DOI":"10.3390\/s21030751","type":"journal-article","created":{"date-parts":[[2021,1,22]],"date-time":"2021-01-22T11:13:53Z","timestamp":1611314033000},"page":"751","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["WiMonitor: Continuous Long-Term Human Vitality Monitoring Using Commodity Wi-Fi Devices"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1232-6281","authenticated-orcid":false,"given":"Xiaopeng","family":"Niu","sequence":"first","affiliation":[{"name":"Key Laboratory of High Confidence Software Technologies (Ministry of Education), School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China"}]},{"given":"Shengjie","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of High Confidence Software Technologies (Ministry of Education), School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China"}]},{"given":"Yue","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of High Confidence Software Technologies (Ministry of Education), School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China"}]},{"given":"Zhaopeng","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Laboratory of High Confidence Software Technologies (Ministry of Education), School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1740-7440","authenticated-orcid":false,"given":"Dan","family":"Wu","sequence":"additional","affiliation":[{"name":"Key Laboratory of High Confidence Software Technologies (Ministry of Education), School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China"}]},{"given":"Rahul C.","family":"Shah","sequence":"additional","affiliation":[{"name":"Intel Corporation, Santa Clara, CA 95054, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2352-9292","authenticated-orcid":false,"given":"Cagri","family":"Tanriover","sequence":"additional","affiliation":[{"name":"Intel Corporation, Hillsboro, OR 97124, USA"}]},{"given":"Hong","family":"Lu","sequence":"additional","affiliation":[{"name":"Intel Corporation, Santa Clara, CA 95054, USA"}]},{"given":"Daqing","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of High Confidence Software Technologies (Ministry of Education), School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China"},{"name":"T\u00e9l\u00e9com SudPais, Institut Polytechnique de Paris, 91764 Palaiseau, France"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,22]]},"reference":[{"key":"ref_1","unstructured":"Desa, U.N. 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