{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T18:37:41Z","timestamp":1787164661502,"version":"build-2736575974"},"reference-count":34,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,8,6]],"date-time":"2022-08-06T00:00:00Z","timestamp":1659744000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["62020106003"],"award-info":[{"award-number":["62020106003"]}]},{"name":"National Natural Science Foundation of China","award":["62173180"],"award-info":[{"award-number":["62173180"]}]},{"name":"National Natural Science Foundation of China","award":["BK20200015"],"award-info":[{"award-number":["BK20200015"]}]},{"name":"National Natural Science Foundation of China","award":["NC2022003"],"award-info":[{"award-number":["NC2022003"]}]},{"name":"National Natural Science Foundation of China","award":["NE2022002"],"award-info":[{"award-number":["NE2022002"]}]},{"name":"Outstanding Youth Foundation of Jiangsu Province of China","award":["62020106003"],"award-info":[{"award-number":["62020106003"]}]},{"name":"Outstanding Youth Foundation of Jiangsu Province of China","award":["62173180"],"award-info":[{"award-number":["62173180"]}]},{"name":"Outstanding Youth Foundation of Jiangsu Province of China","award":["BK20200015"],"award-info":[{"award-number":["BK20200015"]}]},{"name":"Outstanding Youth Foundation of Jiangsu Province of China","award":["NC2022003"],"award-info":[{"award-number":["NC2022003"]}]},{"name":"Outstanding Youth Foundation of Jiangsu Province of China","award":["NE2022002"],"award-info":[{"award-number":["NE2022002"]}]},{"name":"Qing Lan Project of Jiangsu Province of China","award":["62020106003"],"award-info":[{"award-number":["62020106003"]}]},{"name":"Qing Lan Project of Jiangsu Province of China","award":["62173180"],"award-info":[{"award-number":["62173180"]}]},{"name":"Qing Lan Project of Jiangsu Province of China","award":["BK20200015"],"award-info":[{"award-number":["BK20200015"]}]},{"name":"Qing Lan Project of Jiangsu Province of China","award":["NC2022003"],"award-info":[{"award-number":["NC2022003"]}]},{"name":"Qing Lan Project of Jiangsu Province of China","award":["NE2022002"],"award-info":[{"award-number":["NE2022002"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["62020106003"],"award-info":[{"award-number":["62020106003"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["62173180"],"award-info":[{"award-number":["62173180"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["BK20200015"],"award-info":[{"award-number":["BK20200015"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["NC2022003"],"award-info":[{"award-number":["NC2022003"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["NE2022002"],"award-info":[{"award-number":["NE2022002"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>A practical fixed-time fault estimation observer strategy for non-linear systems using an unknown input observer scheme is investigated. The external disturbances of non-linear systems are decoupled by an unknown input observer technique; therefore, the constructed error dynamics do not include these disturbances. The fixed-time fault estimation observer is then constructed. Moreover, a non-linear fault estimator with two power functions is proposed to improve the convergence speed of fault estimation. Finally, simulation results of a non-linear Lorenz chaotic system are provided to demonstrate the feasibility of the presented strategy.<\/jats:p>","DOI":"10.3390\/sym14081618","type":"journal-article","created":{"date-parts":[[2022,8,10]],"date-time":"2022-08-10T09:47:06Z","timestamp":1660124826000},"page":"1618","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["UIO-Based Practical Fixed-Time Fault Estimation Observer Design of Nonlinear Systems"],"prefix":"10.3390","volume":"14","author":[{"given":"Jingping","family":"Xia","sequence":"first","affiliation":[{"name":"College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9153-4360","authenticated-orcid":false,"given":"Bin","family":"Jiang","sequence":"additional","affiliation":[{"name":"College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ke","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1109\/TAC.2004.841889","article-title":"Unknown input proportional multiple-integral observer design for linear descriptor systems: Application to state and fault estimation","volume":"50","author":"Koenig","year":"2005","journal-title":"IEEE Trans. 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