{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T15:39:40Z","timestamp":1762875580054,"version":"build-2065373602"},"reference-count":62,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2014,2,12]],"date-time":"2014-02-12T00:00:00Z","timestamp":1392163200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Wireless visual sensor networks have been considered for a large set of monitoring applications related with surveillance, tracking and multipurpose visual monitoring. When sensors are deployed over a monitored field, permanent faults may happen during the network lifetime, reducing the monitoring quality or rendering parts  or the entire network unavailable. In a different way from scalar sensor networks,  camera-enabled sensors collect information following a directional sensing model, which changes the notions of vicinity and redundancy. Moreover, visual source nodes may have different relevancies for the applications, according to the monitoring requirements and cameras\u2019 poses. In this paper we discuss the most relevant availability issues related to wireless visual sensor networks, addressing availability evaluation and enhancement. Such discussions are valuable when designing, deploying and managing wireless visual sensor networks, bringing significant contributions to these networks.<\/jats:p>","DOI":"10.3390\/s140202795","type":"journal-article","created":{"date-parts":[[2014,2,12]],"date-time":"2014-02-12T11:35:37Z","timestamp":1392204937000},"page":"2795-2821","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Availability Issues in Wireless Visual Sensor Networks"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3988-8476","authenticated-orcid":false,"given":"Daniel","family":"Costa","sequence":"first","affiliation":[{"name":"DTEC-UEFS, State University of Feira de Santana, Feira de Santana 44036-900, Brazil"}]},{"given":"Ivanovitch","family":"Silva","sequence":"additional","affiliation":[{"name":"IMD-UFRN, Federal University of Rio Grande do Norte, Natal 59072-970, Brazil"}]},{"given":"Luiz","family":"Guedes","sequence":"additional","affiliation":[{"name":"DCA-CT-UFRN, Federal University of Rio Grande do Norte, Natal 59072-970, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3115-0901","authenticated-orcid":false,"given":"Francisco","family":"Vasques","sequence":"additional","affiliation":[{"name":"IDMEC-FEUP-UP, University of Porto, Porto 4200-465, Portugal"}]},{"given":"Paulo","family":"Portugal","sequence":"additional","affiliation":[{"name":"INESC TEC-FEUP-UP, University of Porto, Porto 4200-465, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2014,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2292","DOI":"10.1016\/j.comnet.2008.04.002","article-title":"Wireless sensor network survey","volume":"52","author":"Yick","year":"2008","journal-title":"Comput. 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