{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T11:10:44Z","timestamp":1783422644932,"version":"3.54.6"},"reference-count":35,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,8]],"date-time":"2023-02-08T00:00:00Z","timestamp":1675814400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Yunnan Fundamental Research Project, China","award":["202201BE070001-026"],"award-info":[{"award-number":["202201BE070001-026"]}]},{"name":"Yunnan Fundamental Research Project, China","award":["202101AU070031"],"award-info":[{"award-number":["202101AU070031"]}]},{"name":"Yunnan Fundamental Research Project, China","award":["KUST-xk2022001"],"award-info":[{"award-number":["KUST-xk2022001"]}]},{"name":"Yunnan Fundamental Research Project, China","award":["20220615ZZ07110003"],"award-info":[{"award-number":["20220615ZZ07110003"]}]},{"name":"Yunnan Fundamental Research Project, China","award":["YESS20210106"],"award-info":[{"award-number":["YESS20210106"]}]},{"name":"Natural Science Foundation of Yunnan Province, China","award":["202201BE070001-026"],"award-info":[{"award-number":["202201BE070001-026"]}]},{"name":"Natural Science Foundation of Yunnan Province, China","award":["202101AU070031"],"award-info":[{"award-number":["202101AU070031"]}]},{"name":"Natural Science Foundation of Yunnan Province, China","award":["KUST-xk2022001"],"award-info":[{"award-number":["KUST-xk2022001"]}]},{"name":"Natural Science Foundation of Yunnan Province, China","award":["20220615ZZ07110003"],"award-info":[{"award-number":["20220615ZZ07110003"]}]},{"name":"Natural Science Foundation of Yunnan Province, China","award":["YESS20210106"],"award-info":[{"award-number":["YESS20210106"]}]},{"name":"Interdisciplinary Research Project of Kunming University of Science and Technology","award":["202201BE070001-026"],"award-info":[{"award-number":["202201BE070001-026"]}]},{"name":"Interdisciplinary Research Project of Kunming University of Science and Technology","award":["202101AU070031"],"award-info":[{"award-number":["202101AU070031"]}]},{"name":"Interdisciplinary Research Project of Kunming University of Science and Technology","award":["KUST-xk2022001"],"award-info":[{"award-number":["KUST-xk2022001"]}]},{"name":"Interdisciplinary Research Project of Kunming University of Science and Technology","award":["20220615ZZ07110003"],"award-info":[{"award-number":["20220615ZZ07110003"]}]},{"name":"Interdisciplinary Research Project of Kunming University of Science and Technology","award":["YESS20210106"],"award-info":[{"award-number":["YESS20210106"]}]},{"name":"Young Talent Training Program for Science and Technology Think Tank by the China Association for Science and Technology","award":["202201BE070001-026"],"award-info":[{"award-number":["202201BE070001-026"]}]},{"name":"Young Talent Training Program for Science and Technology Think Tank by the China Association for Science and Technology","award":["202101AU070031"],"award-info":[{"award-number":["202101AU070031"]}]},{"name":"Young Talent Training Program for Science and Technology Think Tank by the China Association for Science and Technology","award":["KUST-xk2022001"],"award-info":[{"award-number":["KUST-xk2022001"]}]},{"name":"Young Talent Training Program for Science and Technology Think Tank by the China Association for Science and Technology","award":["20220615ZZ07110003"],"award-info":[{"award-number":["20220615ZZ07110003"]}]},{"name":"Young Talent Training Program for Science and Technology Think Tank by the China Association for Science and Technology","award":["YESS20210106"],"award-info":[{"award-number":["YESS20210106"]}]},{"name":"Young Elite Scientist Sponsorship Program by the China Association for Science and Technology","award":["202201BE070001-026"],"award-info":[{"award-number":["202201BE070001-026"]}]},{"name":"Young Elite Scientist Sponsorship Program by the China Association for Science and Technology","award":["202101AU070031"],"award-info":[{"award-number":["202101AU070031"]}]},{"name":"Young Elite Scientist Sponsorship Program by the China Association for Science and Technology","award":["KUST-xk2022001"],"award-info":[{"award-number":["KUST-xk2022001"]}]},{"name":"Young Elite Scientist Sponsorship Program by the China Association for Science and Technology","award":["20220615ZZ07110003"],"award-info":[{"award-number":["20220615ZZ07110003"]}]},{"name":"Young Elite Scientist Sponsorship Program by the China Association for Science and Technology","award":["YESS20210106"],"award-info":[{"award-number":["YESS20210106"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, a visualization experiment for rectangular channels was carried out to explore gas\u2013liquid two-phase flow characteristics. Typical flow patterns, including bubble, elastic and mixed flows, were captured by direct imaging technology and the corresponding measurements with fluctuation characteristics were recorded by using an electrical conductivity sensor. Time-domain and frequency-domain characteristics of the corresponding electrical conductivity measurements of each flow pattern were analyzed with a probability density function and a power spectral density curve. The results showed that the feature vectors can be constructed to reflect the time\u2013frequency characteristics of conductivity measurements successfully by introducing the quantized characteristic parameters, including the maximum power of the frequency, the standard deviation of the power spectral density, and the range of the power distribution. Furthermore, the overall recognition rate of the four flow patterns measured by the method was 93.33% based on the support vector machine, and the intelligent two-phase flow-pattern identification method can provide a new technical support for the online recognition of gas\u2013liquid two-phase flow patterns in rectangular channels. It may thus be concluded that this method should be of great significance to ensure the safe and efficient operation of relevant industrial production systems.<\/jats:p>","DOI":"10.3390\/s23041907","type":"journal-article","created":{"date-parts":[[2023,2,8]],"date-time":"2023-02-08T05:37:31Z","timestamp":1675834651000},"page":"1907","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Identifying Flow Patterns in a Narrow Channel via Feature Extraction of Conductivity Measurements with a Support Vector Machine"],"prefix":"10.3390","volume":"23","author":[{"given":"Kai","family":"Yang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China"},{"name":"Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiajia","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China"},{"name":"Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9233-7844","authenticated-orcid":false,"given":"Min","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Management Science and Statistics, The University of Texas at San Antonio, San Antonio, TX 78249-0634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hua","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9982-7494","authenticated-orcid":false,"given":"Qingtai","family":"Xiao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China"},{"name":"Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"118551","DOI":"10.1016\/j.applthermaleng.2022.118551","article-title":"Experimental and mechanical research on CHF characteristics during combined\/bottom quenching in narrow rectangular channel","volume":"212","author":"Xu","year":"2022","journal-title":"Appl. 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