{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,17]],"date-time":"2025-10-17T14:29:11Z","timestamp":1760711351077,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,4,20]],"date-time":"2024-04-20T00:00:00Z","timestamp":1713571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key Research and Development Program of China","award":["2021YFC3001902","KJGG2022-0202","2021-GT-133"],"award-info":[{"award-number":["2021YFC3001902","KJGG2022-0202","2021-GT-133"]}]},{"DOI":"10.13039\/501100003764","name":"China National Offshore Oil Corporation","doi-asserted-by":"publisher","award":["2021YFC3001902","KJGG2022-0202","2021-GT-133"],"award-info":[{"award-number":["2021YFC3001902","KJGG2022-0202","2021-GT-133"]}],"id":[{"id":"10.13039\/501100003764","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Boeing-COMAC Sustainable Aviation Technology Centre","award":["2021YFC3001902","KJGG2022-0202","2021-GT-133"],"award-info":[{"award-number":["2021YFC3001902","KJGG2022-0202","2021-GT-133"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Aircraft wake vortices are serious threats to aviation safety. The Pulsed Coherent Doppler Lidar (PCDL) has been widely used in the observation of aircraft wake vortices due to its advantages of high spatial-temporal resolution and high precision. However, the post-processing algorithms require significant computing resources, which cannot achieve the real-time detection of a wake vortex (WV). This paper presents an improved Convolutional Neural Network (CNN) method for WV locating and grading based on PCDL data to avoid the influence of unstable ambient wind fields on the localization and classification results of WV. Typical WV cases are selected for analysis, and the WV locating and grading models are validated on different test sets. The consistency of the analytical algorithm and the CNN algorithm is verified. The results indicate that the improved CNN method achieves satisfactory recognition accuracy with higher efficiency and better robustness, especially in the case of strong turbulence, where the CNN method recognizes the wake vortex while the analytical method cannot. The improved CNN method is expected to be applied to optimize the current aircraft spacing criteria, which is promising in terms of aviation safety and economic benefit improvement.<\/jats:p>","DOI":"10.3390\/rs16081463","type":"journal-article","created":{"date-parts":[[2024,4,22]],"date-time":"2024-04-22T03:57:07Z","timestamp":1713758227000},"page":"1463","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Locating and Grading of Lidar-Observed Aircraft Wake Vortex Based on Convolutional Neural Networks"],"prefix":"10.3390","volume":"16","author":[{"given":"Xinyu","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"}]},{"given":"Hongwei","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"},{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Laoshan Laboratory, No. 168, Wenhai Road, Qingdao 266237, China"}]},{"given":"Qichao","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"},{"name":"Leice Transient Technology Co., Ltd., Qingdao 266100, China"}]},{"given":"Xiaoying","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"}]},{"given":"Shouxin","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"},{"name":"Qingdao Air Traffic Management Station, CAAC, Qingdao 266300, China"}]},{"given":"Rongchuan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Sanya Oceanographic Institution, Ocean University of China, Sanya 572000, China"}]},{"given":"Rongzhong","family":"Li","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"},{"name":"Leice Transient Technology Co., Ltd., Qingdao 266100, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7469-1452","authenticated-orcid":false,"given":"Songhua","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"},{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Laoshan Laboratory, No. 168, Wenhai Road, Qingdao 266237, China"},{"name":"Institute for Advanced Ocean Study, Ocean University of China, No. 238, Songling Road, Qingdao 266100, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/j.paerosci.2010.09.002","article-title":"Wake vortex characteristics of transport aircraft","volume":"47","author":"Breitsamter","year":"2011","journal-title":"Prog. 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