{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,15]],"date-time":"2025-11-15T09:55:28Z","timestamp":1763200528263,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,1,9]],"date-time":"2020-01-09T00:00:00Z","timestamp":1578528000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["No. 2017YFC0804503"],"award-info":[{"award-number":["No. 2017YFC0804503"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 51574276 and No. 51675536"],"award-info":[{"award-number":["No. 51574276 and No. 51675536"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012152","name":"National Postdoctoral Program for Innovative Talents","doi-asserted-by":"publisher","award":["BX20190386"],"award-info":[{"award-number":["BX20190386"]}],"id":[{"id":"10.13039\/501100012152","id-type":"DOI","asserted-by":"publisher"}]},{"name":"China Postdoctoral Science Foundation funded project","award":["2019M662461"],"award-info":[{"award-number":["2019M662461"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>It is still a big challenge to identify tiny surface cracks in a rugged weld due to the lift-off variations using the nondestructive testing (NDT) method. In this paper, the signal gradient algorithm is presented to identify the tiny surface crack in the rugged weld using the alternating current field measurement (ACFM) technique. The ACFM simulation model and testing system was set up to obtain the insensitive signal to the lift-off variations. The signal gradient algorithm was presented to process the insensitive signal for the identification of the tiny surface crack in the rugged weld. The results show that the Bz signal is the insensitive signal to lift-off variations caused by the rugged weld. The signal to noise ratio (SNR) of the crack identification signal was greatly improved by the signal gradient algorithm, and a tiny surface crack can be identified effectively in the weld and the heat affected zone (HAZ).<\/jats:p>","DOI":"10.3390\/s20020380","type":"journal-article","created":{"date-parts":[[2020,1,10]],"date-time":"2020-01-10T04:06:51Z","timestamp":1578629211000},"page":"380","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Identification of Tiny Surface Cracks in a Rugged Weld by Signal Gradient Algorithm Using the ACFM Technique"],"prefix":"10.3390","volume":"20","author":[{"given":"Xin\u2019an","family":"Yuan","sequence":"first","affiliation":[{"name":"Center for Offshore Engineering and Safety Technology, China University of Petroleum (East China), Qingdao 266580, China"}]},{"given":"Wei","family":"Li","sequence":"additional","affiliation":[{"name":"Center for Offshore Engineering and Safety Technology, China University of Petroleum (East China), Qingdao 266580, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3247-8730","authenticated-orcid":false,"given":"Xiaokang","family":"Yin","sequence":"additional","affiliation":[{"name":"Center for Offshore Engineering and Safety Technology, China University of Petroleum (East China), Qingdao 266580, China"}]},{"given":"Guoming","family":"Chen","sequence":"additional","affiliation":[{"name":"Center for Offshore Engineering and Safety Technology, China University of Petroleum (East China), Qingdao 266580, China"}]},{"given":"Jianming","family":"Zhao","sequence":"additional","affiliation":[{"name":"Center for Offshore Engineering and Safety Technology, China University of Petroleum (East China), Qingdao 266580, China"}]},{"given":"Weiyu","family":"Jiang","sequence":"additional","affiliation":[{"name":"Center for Offshore Engineering and Safety Technology, China University of Petroleum (East China), Qingdao 266580, China"}]},{"given":"Jiuhao","family":"Ge","sequence":"additional","affiliation":[{"name":"Nondestructive Detection and Monitoring Technology for High Speed Transportation Facilities, Key Laboratory of Ministry of Industry and Information Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, Jiangsu, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,9]]},"reference":[{"doi-asserted-by":"crossref","unstructured":"Taheri, H., Kilpatrick, M., Norvalls, M., Harper, W.J., Koester, L.W., Bigelow, T.A., and Bond, L.J. 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