{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T16:49:49Z","timestamp":1771260589488,"version":"3.50.1"},"reference-count":20,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,5,3]],"date-time":"2020-05-03T00:00:00Z","timestamp":1588464000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012326","name":"International Science and Technology Cooperation Programme","doi-asserted-by":"publisher","award":["201803D421038"],"award-info":[{"award-number":["201803D421038"]}],"id":[{"id":"10.13039\/501100012326","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Metallic waste classification benefits the environment, resource reuse and industrial economy. This paper provides a fast, non-contact and convenient method based on eddy current to classify metals. The characteristic phase to characterize different conductivity is introduced and extracted from mutual inductance in the form of amplitude and phase. This characteristic phase could offer great separation for non-tilting metals. Although it is hard to classify tilting metals by only using the characteristic phase, we propose the technique of phase compensation utilizing photoelectric sensors to obtain the rectified phase corresponding to the non-tilting situation. Finally, we construct a classification algorithm involving phase compensation. By conducting a test, a \r\n          \r\n            \r\n              \r\n                95\r\n                %\r\n              \r\n            \r\n          \r\n         classification rate is achieved.<\/jats:p>","DOI":"10.3390\/s20092608","type":"journal-article","created":{"date-parts":[[2020,5,4]],"date-time":"2020-05-04T14:00:43Z","timestamp":1588600843000},"page":"2608","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Conductivity Classification of Non-Magnetic Tilting Metals by Eddy Current Sensors"],"prefix":"10.3390","volume":"20","author":[{"given":"Yue","family":"Du","sequence":"first","affiliation":[{"name":"School of Instrument and Electronics, North University of China, Taiyuan 030051, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6553-1978","authenticated-orcid":false,"given":"Zhijie","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Instrument and Electronics, North University of China, Taiyuan 030051, China"}]},{"given":"Wuliang","family":"Yin","sequence":"additional","affiliation":[{"name":"School of Instrument and Electronics, North University of China, Taiyuan 030051, China"},{"name":"School of Electrical and Electronic Engineering, University of Manchester, Manchester M60 1QD, UK"}]},{"given":"Shuang","family":"Zhu","sequence":"additional","affiliation":[{"name":"School of Electrical and Electronic Engineering, University of Manchester, Manchester M60 1QD, UK"}]},{"given":"Ziqi","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Electrical and Electronic Engineering, University of Manchester, Manchester M60 1QD, UK"}]},{"given":"Hanyang","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Electrical and Electronic Engineering, University of Manchester, Manchester M60 1QD, UK"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,3]]},"reference":[{"key":"ref_1","first-page":"561","article-title":"Detection of corrosion pits based on an analytically optimised eddy current sensor","volume":"60","author":"Yin","year":"2018","journal-title":"Insight-Non-Destr. 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