{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T20:13:04Z","timestamp":1775679184788,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,2,26]],"date-time":"2024-02-26T00:00:00Z","timestamp":1708905600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Department of Natural Resources of Guangdong Province","award":["GDNRC [2022]19"],"award-info":[{"award-number":["GDNRC [2022]19"]}]},{"name":"Department of Natural Resources of Guangdong Province","award":["NY223137"],"award-info":[{"award-number":["NY223137"]}]},{"name":"Department of Natural Resources of Guangdong Province","award":["62271426"],"award-info":[{"award-number":["62271426"]}]},{"name":"Department of Natural Resources of Guangdong Province","award":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}]},{"name":"Recruiting Talents of Nanjing University of Posts and Telecommunications","award":["GDNRC [2022]19"],"award-info":[{"award-number":["GDNRC [2022]19"]}]},{"name":"Recruiting Talents of Nanjing University of Posts and Telecommunications","award":["NY223137"],"award-info":[{"award-number":["NY223137"]}]},{"name":"Recruiting Talents of Nanjing University of Posts and Telecommunications","award":["62271426"],"award-info":[{"award-number":["62271426"]}]},{"name":"Recruiting Talents of Nanjing University of Posts and Telecommunications","award":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["GDNRC [2022]19"],"award-info":[{"award-number":["GDNRC [2022]19"]}],"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":["NY223137"],"award-info":[{"award-number":["NY223137"]}],"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":["62271426"],"award-info":[{"award-number":["62271426"]}],"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":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Natural Resources Science and Technology Innovation Project of Fujian Province","award":["GDNRC [2022]19"],"award-info":[{"award-number":["GDNRC [2022]19"]}]},{"name":"Natural Resources Science and Technology Innovation Project of Fujian Province","award":["NY223137"],"award-info":[{"award-number":["NY223137"]}]},{"name":"Natural Resources Science and Technology Innovation Project of Fujian Province","award":["62271426"],"award-info":[{"award-number":["62271426"]}]},{"name":"Natural Resources Science and Technology Innovation Project of Fujian Province","award":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Ocean sound speed is important for underwater acoustic applications, such as communications, navigation and localization, where the assumption of uniformly distributed sound speed profiles (SSPs) is generally used and greatly degrades the performance of underwater acoustic systems. The acquisition of SSPs is necessary for the corrections of the sound ray propagation paths. However, the inversion of SSPs is challenging due to the intricate relations of interrelated physical ocean elements and suffers from the high costs of calculations and hardware deployments. This paper proposes a novel sound speed inversion method based on multi-source ocean remote sensing observations and machine learning, which adapts to large-scale sea regions. Firstly, the datasets of SSPs are generated utilizing the Argo thermohaline profiles and the empirical formulas of the sound speed. Then, the SSPs are analyzed utilizing the empirical orthogonal functions (EOFs) to reduce the dimensions of the feature space as well as the computational load. Considering the nonlinear regression relations of SSPs and the observed datasets, a general framework for sound speed inversion is formulated, which combines the designed machine learning models with the reduced-dimensional feature representations, multi-source ocean remote sensing observations and water temperature data. After being well trained, the proposed machine learning models realize the accurate inversion of the targeted ocean region by inputting the real-time ocean environmental data. The experiments verify the advantages of the proposed method in terms of the accuracy and effectiveness compared with conventional methods.<\/jats:p>","DOI":"10.3390\/rs16050814","type":"journal-article","created":{"date-parts":[[2024,2,26]],"date-time":"2024-02-26T11:31:21Z","timestamp":1708947081000},"page":"814","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Sound Speed Inversion Based on Multi-Source Ocean Remote Sensing Observations and Machine Learning"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5848-949X","authenticated-orcid":false,"given":"Xiao","family":"Feng","sequence":"first","affiliation":[{"name":"Shenzhen Research Institute of Xiamen University, Shenzhen 518005, China"},{"name":"School of Communication and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, China"}]},{"given":"Tian","family":"Tian","sequence":"additional","affiliation":[{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2799-8491","authenticated-orcid":false,"given":"Mingzhang","family":"Zhou","sequence":"additional","affiliation":[{"name":"Shenzhen Research Institute of Xiamen University, Shenzhen 518005, China"},{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, Ministry of Natural Resources, Zhangzhou 363099, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8249-1197","authenticated-orcid":false,"given":"Haixin","family":"Sun","sequence":"additional","affiliation":[{"name":"Shenzhen Research Institute of Xiamen University, Shenzhen 518005, China"},{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, Ministry of Natural Resources, Zhangzhou 363099, China"}]},{"given":"Dingzhao","family":"Li","sequence":"additional","affiliation":[{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"}]},{"given":"Feng","family":"Tian","sequence":"additional","affiliation":[{"name":"School of Communication and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6283-7186","authenticated-orcid":false,"given":"Rongbin","family":"Lin","sequence":"additional","affiliation":[{"name":"Shenzhen Research Institute of Xiamen University, Shenzhen 518005, China"},{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, Ministry of Natural Resources, Zhangzhou 363099, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Qiao, G., Bilal, M., Liu, S., Ma, T., Zhao, Y., and Kong, B. 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