{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,30]],"date-time":"2026-05-30T02:10:28Z","timestamp":1780107028577,"version":"3.54.0"},"reference-count":42,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2017,1,24]],"date-time":"2017-01-24T00:00:00Z","timestamp":1485216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004004","name":"University of Trento","doi-asserted-by":"publisher","award":["D-FAB"],"award-info":[{"award-number":["D-FAB"]}],"id":[{"id":"10.13039\/501100004004","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Following an avalanche, one of the factors that affect victims\u2019 chance of survival is the speed with which they are located and dug out. Rescue teams use techniques like trained rescue dogs and electronic transceivers to locate victims. However, the resources and time required to deploy rescue teams are major bottlenecks that decrease a victim\u2019s chance of survival. Advances in the field of Unmanned Aerial Vehicles (UAVs) have enabled the use of flying robots equipped with sensors like optical cameras to assess the damage caused by natural or manmade disasters and locate victims in the debris. In this paper, we propose assisting avalanche search and rescue (SAR) operations with UAVs fitted with vision cameras. The sequence of images of the avalanche debris captured by the UAV is processed with a pre-trained Convolutional Neural Network (CNN) to extract discriminative features. A trained linear Support Vector Machine (SVM) is integrated at the top of the CNN to detect objects of interest. Moreover, we introduce a pre-processing method to increase the detection rate and a post-processing method based on a Hidden Markov Model to improve the prediction performance of the classifier. Experimental results conducted on two different datasets at different levels of resolution show that the detection performance increases with an increase in resolution, while the computation time increases. Additionally, they also suggest that a significant decrease in processing time can be achieved thanks to the pre-processing step.<\/jats:p>","DOI":"10.3390\/rs9020100","type":"journal-article","created":{"date-parts":[[2017,1,24]],"date-time":"2017-01-24T10:20:29Z","timestamp":1485253229000},"page":"100","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":203,"title":["A Convolutional Neural Network Approach for Assisting Avalanche Search and Rescue Operations with UAV Imagery"],"prefix":"10.3390","volume":"9","author":[{"given":"Mesay","family":"Bejiga","sequence":"first","affiliation":[{"name":"Department of Information Engineering and Computer Science University of Trento, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdallah","family":"Zeggada","sequence":"additional","affiliation":[{"name":"Department of Information Engineering and Computer Science University of Trento, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdelhamid","family":"Nouffidj","sequence":"additional","affiliation":[{"name":"D\u00e9partement des T\u00e9l\u00e9communications, Facult\u00e9 d\u2019Electronique et d\u2019Informatique, USTHB BP 32, El-Alia, Bab-Ezzouar, 16111 Algiers, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9745-3732","authenticated-orcid":false,"given":"Farid","family":"Melgani","sequence":"additional","affiliation":[{"name":"Department of Information Engineering and Computer Science University of Trento, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,1,24]]},"reference":[{"key":"ref_1","unstructured":"Society, N.G. 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