{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T22:59:58Z","timestamp":1769727598871,"version":"3.49.0"},"reference-count":49,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,12]],"date-time":"2021-05-12T00:00:00Z","timestamp":1620777600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF)","award":["2020R1A2C2013414"],"award-info":[{"award-number":["2020R1A2C2013414"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Distributed optical fiber sensors are a promising technology for monitoring the structural health of large-scale structures. The fiber sensors are usually coated with nonfragile materials to protect the sensor and are bonded onto the structure using adhesive materials. However, local deformation of the relatively soft coating and adhesive layers hinders strain transfer from the base structure to the optical fiber sensor, which reduces and distorts its strain distribution. In this study, we analytically derive a strain transfer function in terms of strain periods, which enables us to understand how the strain reduces and is distorted in the optical fiber depending on the variation of the strain field. We also propose a method for back-calculating the base structure\u2019s strain field using the reduced and distorted strain distribution in the optical fiber sensor. We numerically demonstrate the back-calculation of the base strain using a composite beam model with an open hole and an attached distributed optical fiber sensor. The new strain transfer function and the proposed back-calculation method can enhance the strain field estimation accuracy in using a distributed optical fiber sensor. This enables us to use a highly durable distributed optical fiber sensor with thick protective layers in precision measurement.<\/jats:p>","DOI":"10.3390\/s21103365","type":"journal-article","created":{"date-parts":[[2021,5,12]],"date-time":"2021-05-12T22:46:14Z","timestamp":1620859574000},"page":"3365","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Strain Transfer Function of Distributed Optical Fiber Sensors and Back-Calculation of the Base Strain Field"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2735-4138","authenticated-orcid":false,"given":"Sangyoung","family":"Yoon","sequence":"first","affiliation":[{"name":"Division of Mechanical System Engineering, Jeonbuk National University, Jeonbuk 54896, Korea"}]},{"given":"Meadeum","family":"Yu","sequence":"additional","affiliation":[{"name":"Division of Mechanical System Engineering, Jeonbuk National University, Jeonbuk 54896, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6969-8190","authenticated-orcid":false,"given":"Eunho","family":"Kim","sequence":"additional","affiliation":[{"name":"Division of Mechanical System Engineering, Jeonbuk National University, Jeonbuk 54896, Korea"},{"name":"Automotive Hi-Technology Research Center &amp; LANL-CBNU Engineering Institute-Korea, Jeonbuk National University, Jeonbuk 54896, Korea"},{"name":"Multifunctional Structural Composite Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Jeonbuk 55324, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4014-0548","authenticated-orcid":false,"given":"Jaesang","family":"Yu","sequence":"additional","affiliation":[{"name":"Division of Mechanical System Engineering, Jeonbuk National University, Jeonbuk 54896, Korea"},{"name":"Multifunctional Structural Composite Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Jeonbuk 55324, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kralovec, C., and Schagerl, M. 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