{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T06:37:15Z","timestamp":1783060635416,"version":"3.54.6"},"reference-count":45,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,20]],"date-time":"2023-04-20T00:00:00Z","timestamp":1681948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["42274119"],"award-info":[{"award-number":["42274119"]}]},{"name":"National Natural Science Foundation of China","award":["XLYC2002082"],"award-info":[{"award-number":["XLYC2002082"]}]},{"name":"National Natural Science Foundation of China","award":["2022YFF1400500"],"award-info":[{"award-number":["2022YFF1400500"]}]},{"name":"Liaoning Revitalization Talents Program","award":["42274119"],"award-info":[{"award-number":["42274119"]}]},{"name":"Liaoning Revitalization Talents Program","award":["XLYC2002082"],"award-info":[{"award-number":["XLYC2002082"]}]},{"name":"Liaoning Revitalization Talents Program","award":["2022YFF1400500"],"award-info":[{"award-number":["2022YFF1400500"]}]},{"name":"National Key Research and Development Plan Key Special Projects of Science and Technology Military Civil Integration","award":["42274119"],"award-info":[{"award-number":["42274119"]}]},{"name":"National Key Research and Development Plan Key Special Projects of Science and Technology Military Civil Integration","award":["XLYC2002082"],"award-info":[{"award-number":["XLYC2002082"]}]},{"name":"National Key Research and Development Plan Key Special Projects of Science and Technology Military Civil Integration","award":["2022YFF1400500"],"award-info":[{"award-number":["2022YFF1400500"]}]},{"name":"Key Project of Science and Technology Commission of the Central Military Commission","award":["42274119"],"award-info":[{"award-number":["42274119"]}]},{"name":"Key Project of Science and Technology Commission of the Central Military Commission","award":["XLYC2002082"],"award-info":[{"award-number":["XLYC2002082"]}]},{"name":"Key Project of Science and Technology Commission of the Central Military Commission","award":["2022YFF1400500"],"award-info":[{"award-number":["2022YFF1400500"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Underwater gravity gradient detection techniques are conducive to ensuring the safety of submersible sailing. In order to improve the accuracy of underwater obstacle detection based on gravity gradient detection technology, this paper studies the gravity gradient underwater obstacle detection method based on the combined support vector regression (SVR) algorithm. First, the gravity gradient difference ratio (GGDR) equation, which is only related to the obstacle\u2019s position, is obtained based on the gravity gradient equation by using the difference and ratio methods. Aiming at solving the shortcomings of the GGDR equation based on Newton\u2013Raphson method (NRM), combined with SVR algorithm, a novel SVR\u2013gravity gradient joint method (SGJM) is proposed. Second, the differential ratio dataset is constructed by simulating the gravity gradient data generated by obstacles, and the obstacle location model is trained using SVR. Four measuring lines were selected to verify the SVR-based positioning model. The verification results show that the mean absolute error of the new method in the x, y, and z directions is less than 5.39 m, the root-mean-square error is less than 7.58 m, and the relative error is less than 4% at a distance of less than 500 m. These evaluation metrics validate the reliability of the novel SGJM-based detection of underwater obstacles. Third, comparative experiments based on the novel SGJM and traditional NRM were carried out. The experimental results show that the positioning accuracy of x and z directions in the obstacle\u2019s position calculation based on the novel SGJM is improved by 88% and 85%, respectively.<\/jats:p>","DOI":"10.3390\/rs15082188","type":"journal-article","created":{"date-parts":[[2023,4,21]],"date-time":"2023-04-21T01:33:43Z","timestamp":1682040823000},"page":"2188","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Improving the Detection Accuracy of Underwater Obstacles Based on a Novel Combined Method of Support Vector Regression and Gravity Gradient"],"prefix":"10.3390","volume":"15","author":[{"given":"Tengda","family":"Fu","sequence":"first","affiliation":[{"name":"School of Geomatics, Liaoning Technical University, Fuxin 123000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Zheng","sequence":"additional","affiliation":[{"name":"School of Geomatics, Liaoning Technical University, Fuxin 123000, China"},{"name":"China Academy of Aerospace Science and Innovation, Beijing 100176, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhaowei","family":"Li","sequence":"additional","affiliation":[{"name":"Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing 100094, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yifan","family":"Shen","sequence":"additional","affiliation":[{"name":"School of Geomatics, Liaoning Technical University, Fuxin 123000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huizhong","family":"Zhu","sequence":"additional","affiliation":[{"name":"School of Geomatics, Liaoning Technical University, Fuxin 123000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aigong","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Geomatics, Liaoning Technical University, Fuxin 123000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1080\/01402390500032070","article-title":"Innovation and Experimentation in the US Navy: The UPTIDE Antisubmarine Warfare Experiments, 1969\u20131972","volume":"28","author":"Angevine","year":"2005","journal-title":"J. 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