{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:09:58Z","timestamp":1760234998574,"version":"build-2065373602"},"reference-count":16,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,19]],"date-time":"2021-07-19T00:00:00Z","timestamp":1626652800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"New Energy and Industrial Technology Development Organization","award":["P19101705\u20100"],"award-info":[{"award-number":["P19101705\u20100"]}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["17H04903"],"award-info":[{"award-number":["17H04903"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100015280","name":"Precise Measurement Technology Promotion Foundation","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/100015280","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper reports on a mask-type sensor for simultaneous pulse wave and respiration measurements and eye blink detection that uses only one sensing element. In the proposed sensor, a flexible air bag-shaped chamber whose inner pressure change can be measured by a microelectromechanical system-based piezoresistive cantilever was used as the sensing element. The air bag-shaped chamber is fabricated by wrapping a sponge pad with plastic film and polyimide tape. The polyimide tape has a hole to which the substrate with the piezoresistive cantilever adheres. By attaching the sensor device to a mask where it contacts the nose of the subject, the sensor can detect the pulses and eye blinks of the subject by detecting the vibration and displacement of the nose skin caused by these physiological parameters. Moreover, the respiration of the subject causes pressure changes in the space between the mask and the face of the subject as well as slight vibrations of the mask. Therefore, information about the respiration of the subject can be extracted from the sensor signal using either the low-frequency component (&lt;1 Hz) or the high-frequency component (&gt;100 Hz). This paper describes the sensor fabrication and provides demonstrations of the pulse wave and respiration measurements as well as eye blink detection using the fabricated sensor.<\/jats:p>","DOI":"10.3390\/s21144895","type":"journal-article","created":{"date-parts":[[2021,7,19]],"date-time":"2021-07-19T04:55:40Z","timestamp":1626670540000},"page":"4895","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Mask-Type Sensor for Pulse Wave and Respiration Measurements and Eye Blink Detection"],"prefix":"10.3390","volume":"21","author":[{"given":"Thanh-Vinh","family":"Nguyen","sequence":"first","affiliation":[{"name":"Sensing System Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8564, Ibaraki, Japan"}]},{"given":"Masaaki","family":"Ichiki","sequence":"additional","affiliation":[{"name":"Sensing System Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8564, Ibaraki, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"451","DOI":"10.1161\/HYPERTENSIONAHA.117.10368","article-title":"Pulse Wave Velocity Predicts the Progression of Blood Pressure and Development of Hypertension in Young Adults","volume":"71","author":"Koivistoinen","year":"2018","journal-title":"Hypertension"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1291\/hypres.30.237","article-title":"Pulse Wave Velocity as a Marker of Arteriosclerosis and Its Comorbidities in Chinese Patients","volume":"30","author":"Liu","year":"2007","journal-title":"Hypertens. 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Med."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Miller, D.J., Capodilupo, J.V., Lastella, M., Sargent, C., Roach, G.D., Lee, V.H., and Capodilupo, E.R. (2020). Analyzing changes in respiratory rate to predict the risk of COVID-19 infection. PLoS ONE, 15.","DOI":"10.1101\/2020.06.18.20131417"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1208","DOI":"10.1038\/s41551-020-00640-6","article-title":"Pre-symptomatic detection of COVID-19 from smartwatch data","volume":"4","author":"Mishra","year":"2020","journal-title":"Nat. Biomed. Eng."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1038\/s41928-020-00533-1","article-title":"Wearable devices for the detection of COVID-19","volume":"4","author":"Ates","year":"2021","journal-title":"Nat. Electron."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Nguyen, T.-V., and Ichiki, M. (2019). MEMS-Based Sensor for Simultaneous Measurement of Pulse Wave and Respiration Rate. 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Microeng."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/14\/4895\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:31:37Z","timestamp":1760164297000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/14\/4895"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,19]]},"references-count":16,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2021,7]]}},"alternative-id":["s21144895"],"URL":"https:\/\/doi.org\/10.3390\/s21144895","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2021,7,19]]}}}