{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T07:05:46Z","timestamp":1777619146990,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2023,7,13]],"date-time":"2023-07-13T00:00:00Z","timestamp":1689206400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013282","name":"National Magnetic Confinement Fusion Program of China","doi-asserted-by":"publisher","award":["2019YFE03130003"],"award-info":[{"award-number":["2019YFE03130003"]}],"id":[{"id":"10.13039\/501100013282","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013282","name":"National Magnetic Confinement Fusion Program of China","doi-asserted-by":"publisher","award":["11927801"],"award-info":[{"award-number":["11927801"]}],"id":[{"id":"10.13039\/501100013282","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013282","name":"National Magnetic Confinement Fusion Program of China","doi-asserted-by":"publisher","award":["52107009"],"award-info":[{"award-number":["52107009"]}],"id":[{"id":"10.13039\/501100013282","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013282","name":"National Magnetic Confinement Fusion Program of China","doi-asserted-by":"publisher","award":["2023-YBGY-411"],"award-info":[{"award-number":["2023-YBGY-411"]}],"id":[{"id":"10.13039\/501100013282","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2019YFE03130003"],"award-info":[{"award-number":["2019YFE03130003"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["11927801"],"award-info":[{"award-number":["11927801"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52107009"],"award-info":[{"award-number":["52107009"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2023-YBGY-411"],"award-info":[{"award-number":["2023-YBGY-411"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Key R&amp;D Project in Shaanxi Province","award":["2019YFE03130003"],"award-info":[{"award-number":["2019YFE03130003"]}]},{"name":"Key R&amp;D Project in Shaanxi Province","award":["11927801"],"award-info":[{"award-number":["11927801"]}]},{"name":"Key R&amp;D Project in Shaanxi Province","award":["52107009"],"award-info":[{"award-number":["52107009"]}]},{"name":"Key R&amp;D Project in Shaanxi Province","award":["2023-YBGY-411"],"award-info":[{"award-number":["2023-YBGY-411"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Glass Fiber reinforced polymers (GFRPs) are widely used and play an important role in modern society. The multilayer structure of GFRPs can lead to delamination defects during production and service, which can have a significant impact on the integrity and safety of the equipment. Therefore, it is important to monitor these delamination defects during equipment service in order to evaluate their effects on equipment performance and lifespan. Microwave imaging testing, with its high sensitivity and noncontact nature, shows promise as a potential method for detecting delamination defects in GFRPs. However, there is currently limited research on the quantitative characterization of defect images in this field. In order to achieve visual quantitative nondestructive testing (NDT), we propose a 2D-imaging visualization and quantitative characterization method for delamination defects in GFRP, and realize the combination of visual detection and quantitative detection. We built a microwave testing experimental system to verify the effectiveness of the proposed method. The results of the experiment indicate the effectiveness and innovation of the method, which can effectively detect all delamination defects of 0.5 mm thickness inside GFRP with high accuracy, the signal-to-background ratio (SBR) of 2D imaging can reach 4.41 dB, the quantitative error of position is within 0.5 mm, and the relative error of area is within 11%.<\/jats:p>","DOI":"10.3390\/s23146386","type":"journal-article","created":{"date-parts":[[2023,7,14]],"date-time":"2023-07-14T00:49:30Z","timestamp":1689295770000},"page":"6386","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Visual Quantitative Detection of Delamination Defects in GFRP via Microwave"],"prefix":"10.3390","volume":"23","author":[{"given":"Xihan","family":"Yang","sequence":"first","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Centre of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7004-4968","authenticated-orcid":false,"given":"Yang","family":"Fang","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Centre of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruonan","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Centre of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4257-2771","authenticated-orcid":false,"given":"Yong","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Centre of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhenmao","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Centre of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1080\/10589759.2019.1605603","article-title":"A review of microwave testing of glass fibre reinforced polymer composites","volume":"34","author":"Li","year":"2019","journal-title":"Nondestruct. 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