{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T01:20:53Z","timestamp":1769908853781,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2014,3,28]],"date-time":"2014-03-28T00:00:00Z","timestamp":1395964800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Oil debris sensors are effective tools to monitor wear particles in lubricants.  For in situ applications, surrounding noise and vibration interferences often distort the oil debris signature of the sensor. Hence extracting oil debris signatures from sensor signals is a challenging task for wear particle monitoring. In this paper we employ the maximal overlap discrete wavelet transform (MODWT) with optimal decomposition depth to enhance the wear particle monitoring capability. The sensor signal is decomposed by the MODWT into different depths for detecting the wear particle existence. To extract the authentic particle signature with minimal distortion, the root mean square deviation of kurtosis value of the segmented signal residue is adopted as a criterion to obtain the optimal decomposition depth for the MODWT. The proposed approach is evaluated using both simulated and experimental wear particles. The results show that the present method can improve the oil debris monitoring capability without structural upgrade requirements.<\/jats:p>","DOI":"10.3390\/s140406207","type":"journal-article","created":{"date-parts":[[2014,3,28]],"date-time":"2014-03-28T19:31:49Z","timestamp":1396035109000},"page":"6207-6228","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Enhancement of the Wear Particle Monitoring Capability of Oil Debris Sensors Using a Maximal Overlap Discrete Wavelet Transform with Optimal Decomposition Depth"],"prefix":"10.3390","volume":"14","author":[{"given":"Chuan","family":"Li","sequence":"first","affiliation":[{"name":"Chongqing Key Laboratory of Manufacturing Equipment Mechanism Design and Control, Chongqing Technology and Business University, Chongqing 400067, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juan","family":"Peng","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Manufacturing Equipment Mechanism Design and Control, Chongqing Technology and Business University, Chongqing 400067, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ming","family":"Liang","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Ottawa, ON K1N 6N5, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"382","DOI":"10.3390\/s150100382","article-title":"Vibration sensor data denoising using a time-frequency manifold for machinery fault diagnosis","volume":"14","author":"Wang","year":"2014","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1339","DOI":"10.1016\/j.ymssp.2010.11.007","article-title":"The combined use of vibration, acoustic emission and oil debris on-line monitoring towards a more effective condition monitoring of rotating machinery","volume":"25","author":"Loutas","year":"2011","journal-title":"Mech. 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