{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:40:29Z","timestamp":1760190029279,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2019,9,8]],"date-time":"2019-09-08T00:00:00Z","timestamp":1567900800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41576031 and 51120195001"],"award-info":[{"award-number":["41576031 and 51120195001"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ocean acidification is changing the chemical environment on which marine life depends. It causes a decrease in seawater pH and changes the water quality parameters of seawater. Changes in water quality parameters may affect pH, a key indicator for assessing ocean acidification. Therefore, it is particularly important to study the correlation between pH and various water quality parameters. In this paper, several water quality parameters with potential correlation with pH are investigated, and multiple linear regression, softmax regression, and support vector machine are used to perform multi-classification. Most importantly, experimental data were collected from Weizhou Island, China. The classification results show that the pH has a strong correlation with salinity, temperature, and dissolved oxygen. The prediction accuracy of the classification is good, and the correlation with dissolved oxygen is the most significant. The prediction accuracies of the three methods for multi-classifiers based on the above three factors reach 87.01%, 87.77%, and 89.04%, respectively.<\/jats:p>","DOI":"10.3390\/s19183875","type":"journal-article","created":{"date-parts":[[2019,9,9]],"date-time":"2019-09-09T04:12:40Z","timestamp":1568002360000},"page":"3875","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Prediction of pH Value by Multi-Classification in the Weizhou Island Area"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8096-0439","authenticated-orcid":false,"given":"Haocai","family":"Huang","sequence":"first","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"},{"name":"Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China"}]},{"given":"Rendong","family":"Feng","sequence":"additional","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"}]},{"given":"Jiang","family":"Zhu","sequence":"additional","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"}]},{"given":"Peiliang","family":"Li","sequence":"additional","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,8]]},"reference":[{"key":"ref_1","unstructured":"(2019, July 06). 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