{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T19:07:14Z","timestamp":1774638434217,"version":"3.50.1"},"reference-count":22,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2017,5,8]],"date-time":"2017-05-08T00:00:00Z","timestamp":1494201600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Monitoring multiple biosignals, such as heart rate, respiration cycle, and weight transitions, contributes to the health management of individuals. Specifically, it is possible to measure multiple biosignals using load information obtained through contact with the environment, such as a chair and bed, in daily use. A wide-range load sensor is essential since load information contains multiple biosignals with various load ranges. In this study, a load sensor is presented by using a quartz crystal resonator (QCR) with a wide measurement range of 1.5 \u00d7 106 (0.4 mN to 600 N), and its temperature characteristic of load is improved to \u22127 Hz\/\u00b0C (\u221218 mN\/\u00b0C). In order to improve the measurement range of the load, a design method of this sensor is proposed by restraining the buckling of QCR and by using a thinner QCR. The proposed sensor allows a higher allowable load with high sensitivity. The load sensor mainly consists of three layers, namely a QCR layer and two holding layers. As opposed to the conventional holding layer composed of silicon, quartz crystal is utilized for the holding layers to improve the temperature characteristic of the load sensor. In the study, multiple biosignals, such as weight and pulse, are detected by using a fabricated sensor.<\/jats:p>","DOI":"10.3390\/s17051067","type":"journal-article","created":{"date-parts":[[2017,5,8]],"date-time":"2017-05-08T11:45:16Z","timestamp":1494243916000},"page":"1067","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Improvement of the Measurement Range and Temperature Characteristics of a Load Sensor Using a Quartz Crystal Resonator with All Crystal Layer Components"],"prefix":"10.3390","volume":"17","author":[{"given":"Yuichi","family":"Murozaki","sequence":"first","affiliation":[{"name":"Department of Micro-Nano Systems Engineering, Nagoya University, Nagoya 464-8603, Japan"}]},{"given":"Shinya","family":"Sakuma","sequence":"additional","affiliation":[{"name":"Department of Micro-Nano Systems Engineering, Nagoya University, Nagoya 464-8603, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2508-1615","authenticated-orcid":false,"given":"Fumihito","family":"Arai","sequence":"additional","affiliation":[{"name":"Department of Micro-Nano Systems Engineering, Nagoya University, Nagoya 464-8603, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2017,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"423","DOI":"10.1016\/j.sna.2007.11.019","article-title":"Flexible polymeric dry electrodes for the long-term monitoring of ECG","volume":"143","author":"Baek","year":"2008","journal-title":"Sens. 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