{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T23:44:55Z","timestamp":1787701495316,"version":"build-2784847793"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,12,20]],"date-time":"2019-12-20T00:00:00Z","timestamp":1576800000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Center for Advanced Soft Electronics under the Global Frontier Research Program","award":["2012M3A6A5055728"],"award-info":[{"award-number":["2012M3A6A5055728"]}]},{"name":"Sports Promotion Fund of Seoul Olympic Sports Promotion Foundation from Ministry of Culture, Sports and Tourism","award":["s072016022016"],"award-info":[{"award-number":["s072016022016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Numerous wearable sensors have been developed for a variety of needs in medical\/healthcare\/wellness\/sports applications, but there are still doubts about their usefulness due to uncomfortable fit or frequent battery charging. Because the size or capacity of battery is the major factor affecting the convenience of wearable sensors, power consumption must be reduced. We developed a method that can significantly reduce the power consumption by introducing a signal repeater and a special switch that provides power only when needed. Antenna radiation characteristics are an important factor in wireless wearable sensors, but soft material encapsulation for comfortable fit results in poor wireless performance. We improved the antenna radiation characteristics by a local encapsulation patterning. In particular, ultra-low power operation enables the use of paper battery to achieve a very thin and flexible form factor. Also, we verified the human body safety through specific absorption rate simulations. With these methods, we demonstrated a wearable infant sleep position sensor. Infants are unable to call for help in unsafe situations, and it is not easy for caregivers to observe them all the time. Our wearable sensor detects infants\u2019 sleep positions in real time and automatically alerts the caregivers when needed.<\/jats:p>","DOI":"10.3390\/s20010061","type":"journal-article","created":{"date-parts":[[2019,12,23]],"date-time":"2019-12-23T03:15:01Z","timestamp":1577070901000},"page":"61","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Ultra-Low Power Wearable Infant Sleep Position Sensor"],"prefix":"10.3390","volume":"20","author":[{"given":"Inyeol","family":"Yun","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinpyeo","family":"Jeung","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mijung","family":"Kim","sequence":"additional","affiliation":[{"name":"Korea Sport Industry Development Institute, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Young-Seok","family":"Kim","sequence":"additional","affiliation":[{"name":"Korea Sport Industry Development Institute, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8348-7042","authenticated-orcid":false,"given":"Yoonyoung","family":"Chung","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Chung, H.U., Kim, B.H., Lee, J.Y., Lee, J., Xie, Z.Q., Ibler, E.M., Lee, K., Banks, A., Jeong, J.Y., and Kim, J. 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