{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T14:19:54Z","timestamp":1768832394000,"version":"3.49.0"},"reference-count":53,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,10,10]],"date-time":"2020-10-10T00:00:00Z","timestamp":1602288000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["204691\/2018-4"],"award-info":[{"award-number":["204691\/2018-4"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["303527\/2018-8"],"award-info":[{"award-number":["303527\/2018-8"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JSAN"],"abstract":"<jats:p>The adoption of emergency alerting systems can bring countless benefits when managing urban areas, industrial plants, farms, roads and virtually any area that is subject to the occurrence of critical events, supporting in rescue operations and reducing their negative impacts. For such systems, a promising approach is to exploit scalar sensors to detect events of interest, allowing for the distributed monitoring of different variables. However, the use of cameras as visual sensors can enhance the detection of critical events, which can be employed along with scalar sensors for a more comprehensive perception of the environment. Although the particularities of visual sensing may be challenging in some scenarios, the combination of scalar and visual sensors for the early detection of emergency situations can be valuable for many scenarios, such as smart cities and industry 4.0, bringing promising results. Therefore, in this article, we extend a sensors-based emergency detection and alerting system to also exploit visual monitoring when identifying critical events. Implementation and experimental details are provided to reinforce the use of cameras as a relevant sensor unit, bringing promising results for emergencies management.<\/jats:p>","DOI":"10.3390\/jsan9040046","type":"journal-article","created":{"date-parts":[[2020,10,12]],"date-time":"2020-10-12T10:18:00Z","timestamp":1602497880000},"page":"46","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["On the Use of Cameras for the Detection of Critical Events in Sensors-Based Emergency Alerting Systems"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3988-8476","authenticated-orcid":false,"given":"Daniel G.","family":"Costa","sequence":"first","affiliation":[{"name":"Department of Technology, State University of Feira de Santana, Feira de Santana 44036-900, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3115-0901","authenticated-orcid":false,"given":"Francisco","family":"Vasques","sequence":"additional","affiliation":[{"name":"INEGI\/INESC-TEC\u2014Faculty of Engineering, University of Porto, Porto 4200-465, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6386-9753","authenticated-orcid":false,"given":"Paulo","family":"Portugal","sequence":"additional","affiliation":[{"name":"INEGI\/INESC-TEC\u2014Faculty of Engineering, University of Porto, Porto 4200-465, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6020-8087","authenticated-orcid":false,"given":"Ana","family":"Aguiar","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es (IT), University of Porto, Porto 4200-465, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1016\/j.scs.2018.11.033","article-title":"Can cities become smart without being sustainable? 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