{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T14:58:16Z","timestamp":1781621896728,"version":"3.54.5"},"reference-count":31,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2016,9,7]],"date-time":"2016-09-07T00:00:00Z","timestamp":1473206400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents an image reconstruction method to monitor the temperature distribution of electric generator stators. The main objective is to identify insulation failures that may arise as hotspots in the structure. The method is based on temperature readings of fiber optic distributed sensors (DTS) and a sparse reconstruction algorithm. Thermal images of the structure are formed by appropriately combining atoms of a dictionary of hotspots, which was constructed by finite element simulation with a multi-physical model. Due to difficulties for reproducing insulation faults in real stator structure, experimental tests were performed using a prototype similar to the real structure. The results demonstrate the ability of the proposed method to reconstruct images of hotspots with dimensions down to 15 cm, representing a resolution gain of up to six times when compared to the DTS spatial resolution. In addition, satisfactory results were also obtained to detect hotspots with only 5 cm. The application of the proposed algorithm for thermal imaging of generator stators can contribute to the identification of insulation faults in early stages, thereby avoiding catastrophic damage to the structure.<\/jats:p>","DOI":"10.3390\/s16091425","type":"journal-article","created":{"date-parts":[[2016,9,7]],"date-time":"2016-09-07T09:59:46Z","timestamp":1473242386000},"page":"1425","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Sparse Reconstruction for Temperature Distribution Using DTS Fiber Optic Sensors with Applications in Electrical Generator Stator Monitoring"],"prefix":"10.3390","volume":"16","author":[{"given":"Jo\u00e3o","family":"Bazzo","sequence":"first","affiliation":[{"name":"Graduate Program in Electrical and Computer Engineering (CPGEI)\/Federal University of Technology-Parana, Curitiba 80230-901, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9398-332X","authenticated-orcid":false,"given":"Daniel","family":"Pipa","sequence":"additional","affiliation":[{"name":"Graduate Program in Electrical and Computer Engineering (CPGEI)\/Federal University of Technology-Parana, Curitiba 80230-901, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erlon","family":"Da Silva","sequence":"additional","affiliation":[{"name":"Engie Brasil Energia, Saudades do Igua\u00e7u 85568-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cicero","family":"Martelli","sequence":"additional","affiliation":[{"name":"Graduate Program in Electrical and Computer Engineering (CPGEI)\/Federal University of Technology-Parana, Curitiba 80230-901, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2310-9159","authenticated-orcid":false,"given":"Jean","family":"Cardozo da Silva","sequence":"additional","affiliation":[{"name":"Graduate Program in Electrical and Computer Engineering (CPGEI)\/Federal University of Technology-Parana, Curitiba 80230-901, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,9,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Tagare, D.M. 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