{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T16:00:16Z","timestamp":1772121616228,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2024,11,21]],"date-time":"2024-11-21T00:00:00Z","timestamp":1732147200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Oceans and Fisheries","award":["RS-2021-KS211502"],"award-info":[{"award-number":["RS-2021-KS211502"]}]},{"name":"Ministry of Oceans and Fisheries","award":["RS-2023-00280650"],"award-info":[{"award-number":["RS-2023-00280650"]}]},{"name":"Korea Government","award":["RS-2021-KS211502"],"award-info":[{"award-number":["RS-2021-KS211502"]}]},{"name":"Korea Government","award":["RS-2023-00280650"],"award-info":[{"award-number":["RS-2023-00280650"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Increasing global plastic usage has raised critical concerns regarding marine pollution. This study addresses the pressing issue of floating marine macro-litter (FMML) by developing a novel monitoring system using a multi-spectral sensor and drones along the southern coast of South Korea. Subsequently, a convolutional neural network (CNN) model was utilized to classify four distinct marine litter materials: film, fiber, fragment, and foam. Automatic atmospheric correction with the drone data atmospheric correction (DROACOR) method, which is specifically designed for currently available drone-based sensors, ensured consistent reflectance across altitudes in the FMML dataset. The CNN models exhibited promising performance, with precision, recall, and F1 score values of 0.9, 0.88, and 0.89, respectively. Furthermore, gradient-weighted class activation mapping (Grad-CAM), an object recognition technique, allowed us to interpret the classification performance. Overall, this study will shed light on successful FMML identification using multi-spectral observations for broader applications in diverse marine environments.<\/jats:p>","DOI":"10.3390\/rs16234347","type":"journal-article","created":{"date-parts":[[2024,11,21]],"date-time":"2024-11-21T06:57:54Z","timestamp":1732172274000},"page":"4347","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Study on the Monitoring of Floating Marine Macro-Litter Using a Multi-Spectral Sensor and Classification Based on Deep Learning"],"prefix":"10.3390","volume":"16","author":[{"given":"Youchul","family":"Jeong","sequence":"first","affiliation":[{"name":"Marine Research Institute, Pusan National University, Busan 46241, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0700-1175","authenticated-orcid":false,"given":"Jisun","family":"Shin","sequence":"additional","affiliation":[{"name":"Marine Research Institute, Pusan National University, Busan 46241, Republic of Korea"}]},{"given":"Jong-Seok","family":"Lee","sequence":"additional","affiliation":[{"name":"BK21 School of Earth and Environmental Systems, Pusan National University, Busan 46241, Republic of Korea"}]},{"given":"Ji-Yeon","family":"Baek","sequence":"additional","affiliation":[{"name":"BK21 School of Earth and Environmental Systems, Pusan National University, Busan 46241, Republic of Korea"},{"name":"Korea Ocean Satellite Center, Korea Institute of Ocean Science and Technology, Busan 49111, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6448-4858","authenticated-orcid":false,"given":"Daniel","family":"Schl\u00e4pfer","sequence":"additional","affiliation":[{"name":"ReSe Applications LLC, 9500 Wil, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-5215-240X","authenticated-orcid":false,"given":"Sin-Young","family":"Kim","sequence":"additional","affiliation":[{"name":"BK21 School of Earth and Environmental Systems, Pusan National University, Busan 46241, Republic of Korea"}]},{"given":"Jin-Yong","family":"Jeong","sequence":"additional","affiliation":[{"name":"Marine Disaster Research Department, Korea Institute of Ocean Science and Technology, Busan 49111, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8013-998X","authenticated-orcid":false,"given":"Young-Heon","family":"Jo","sequence":"additional","affiliation":[{"name":"Marine Research Institute, Pusan National University, Busan 46241, Republic of Korea"},{"name":"Department of Oceanography, Pusan National University, Busan 46241, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,21]]},"reference":[{"key":"ref_1","unstructured":"UNEP (2016). 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