{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:18:06Z","timestamp":1760059086519,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,19]],"date-time":"2025-05-19T00:00:00Z","timestamp":1747612800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Algorithms"],"abstract":"<jats:p>The offshore oil engineering jacket is a giant super-heavy steel frame structure with dimensions in the hundreds of meters. A high-precision free station control network is usually arranged around it to ensure construction accuracy. However, as the jacket is gradually assembled, its extreme weight will cause the widespread deformation of the surrounding ground surface, and each control point may be affected to varying degrees, resulting in the non-uniform deformation of the entire network. For adjustments of control networks in the subsequent phases, if the same starting point as the first phase is chosen without careful analysis, the starting points\u2019 non-uniform deformation will degrade the whole network\u2019s accuracy. Considering the particularities of the free station control network, this paper proposes an adjustment algorithm consisting of a three-step analytical method. Firstly, the initial coordinates of the points of the current phase are obtained through classical free network adjustment; second, stable and unstable points are identified via coordinate similarity transformation between the current and the first phase; and finally, quasi-stable adjustment is conducted. The experimental data analysis of a jacket control network shows that this method can effectively identify stable and unstable points, thereby ensuring construction accuracy and jacket stability.<\/jats:p>","DOI":"10.3390\/a18050292","type":"journal-article","created":{"date-parts":[[2025,5,19]],"date-time":"2025-05-19T11:54:26Z","timestamp":1747655666000},"page":"292","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Adjustment Algorithm for Free Station Control Network of Ultra-Large Deepwater Jacket"],"prefix":"10.3390","volume":"18","author":[{"given":"Xianyang","family":"Yang","sequence":"first","affiliation":[{"name":"Offshore Oil Engineering Co., Ltd., Qingdao 266555, China"}]},{"given":"Wei","family":"Shu","sequence":"additional","affiliation":[{"name":"Offshore Oil Engineering Co., Ltd., Qingdao 266555, China"}]},{"given":"Huoping","family":"Wang","sequence":"additional","affiliation":[{"name":"CNOOC (China) Limited Shenzhen Branch, Shenzhen 518054, China"}]},{"given":"Haifeng","family":"Li","sequence":"additional","affiliation":[{"name":"Offshore Oil Engineering Co., Ltd., Qingdao 266555, China"}]},{"given":"Yi","family":"Wang","sequence":"additional","affiliation":[{"name":"Offshore Oil Engineering Co., Ltd., Qingdao 266555, China"}]},{"given":"Di","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Geodesy and Geomatics, Hubei Luojia Laboratory, Wuhan University, Wuhan 430079, China"}]},{"given":"Jiayu","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Geodesy and Geomatics, Hubei Luojia Laboratory, Wuhan University, Wuhan 430079, China"}]},{"given":"Deyang","family":"Wang","sequence":"additional","affiliation":[{"name":"CNOOC (China) Limited Shenzhen Branch, Shenzhen 518054, China"}]},{"given":"Wangsui","family":"Xiao","sequence":"additional","affiliation":[{"name":"CNOOC (China) Limited Shenzhen Branch, Shenzhen 518054, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"119542","DOI":"10.1016\/j.oceaneng.2024.119542","article-title":"Shaking table test and numerical simulation of jacket offshore platform considering soil-water-structure interaction","volume":"313","author":"Liu","year":"2024","journal-title":"Ocean Eng."},{"key":"ref_2","first-page":"132","article-title":"A method to eliminate the influence of earth curvature on the elevation of very large jackets","volume":"40","author":"Zhang","year":"2022","journal-title":"Nat. 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