{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T00:34:14Z","timestamp":1760229254374,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,6,5]],"date-time":"2022-06-05T00:00:00Z","timestamp":1654387200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key R&amp;D Program of China","award":["2018YFD0700502","2020XTTGCY02-04"],"award-info":[{"award-number":["2018YFD0700502","2020XTTGCY02-04"]}]},{"name":"the Zhejiang Agricultural Major Technology Collaborative Promotion Plan","award":["2018YFD0700502","2020XTTGCY02-04"],"award-info":[{"award-number":["2018YFD0700502","2020XTTGCY02-04"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Tea flow rate is a key indicator in tea production and processing. Due to the small real\u2212time flow of tea leaves on the production line, the noise caused by the transmission system is greater than or close to the real signal of tea leaves. This issue may affect the dynamic measurement accuracy of tea flow. Therefore, a variational mode decomposition combined with a wavelet threshold (VMD\u2212WT) denoising method is proposed to improve the accuracy of tea flow measurement. The denoising method of the tea flow signal based on VMD\u2212WT is established, and the results are compared with WT, VMD, empirical mode decomposition (EMD), and empirical mode decomposition combined with wavelet threshold (EMD\u2212WT). In addition, the dynamic measurement of different tea flow in tea processing is carried out. The result shows that the main noise of tea flow measurement comes from mechanical vibration. The VMD\u2212WT method can effectively remove the noise in the tea dynamic weighing signal, and the denoising performance is better than WT, VMD, EMD, and EMD\u2212WT methods. The average cumulative measurement accuracy of the tea flow signal based on the VMD\u2212WT algorithm is 0.88%, which is 55% higher than that before denoising. This study provides an effective method for dynamic and accurate measurement of tea flow and offers technical support for digital control of the tea processing.<\/jats:p>","DOI":"10.3390\/s22114294","type":"journal-article","created":{"date-parts":[[2022,6,5]],"date-time":"2022-06-05T10:47:11Z","timestamp":1654426031000},"page":"4294","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Research on Dynamic Measurement Method of Flow Rate in Tea Processing"],"prefix":"10.3390","volume":"22","author":[{"given":"Zhangfeng","family":"Zhao","sequence":"first","affiliation":[{"name":"College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310023, China"},{"name":"Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Ministry of Education, Zhejiang University of Technology, Hangzhou 310023, China"}]},{"given":"Gaohong","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310023, China"}]},{"given":"Yueliang","family":"Wang","sequence":"additional","affiliation":[{"name":"Ningbo Yaojiangyuan Machinery Co., Ltd., Ningbo 315444, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2842-170X","authenticated-orcid":false,"given":"Jiyu","family":"Peng","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310023, China"},{"name":"Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Ministry of Education, Zhejiang University of Technology, Hangzhou 310023, China"}]},{"given":"Xin","family":"Qiao","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310023, China"},{"name":"Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Ministry of Education, Zhejiang University of Technology, Hangzhou 310023, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9614-6730","authenticated-orcid":false,"given":"Jiang","family":"Zhong","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310023, China"},{"name":"Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Ministry of Education, Zhejiang University of Technology, Hangzhou 310023, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"59701","DOI":"10.1109\/ACCESS.2020.2983134","article-title":"An Approach for in-Line Control of Moisture Content During Green Tea Processing","volume":"8","author":"Zhao","year":"2020","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"110846","DOI":"10.1016\/j.jfoodeng.2021.110846","article-title":"Intelligent green tea fixation with sensor fusion technology","volume":"317","author":"Song","year":"2022","journal-title":"J. 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