{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T03:43:45Z","timestamp":1782791025902,"version":"3.54.5"},"reference-count":23,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2020,7,14]],"date-time":"2020-07-14T00:00:00Z","timestamp":1594684800000},"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>The ability to know the precise level of occupancy in an indoor or outdoor space in real time could have multiple applications. It is a well-known problem for which a number of technologies have been proposed over time. The recent emergence of BLE beacon technology has provided a solution to the problem. This study presents a tool that uses beacons and user smartphones to determine the level of occupancy in indoor and outdoor spaces, providing real-time information that can be published as open data and subsequently used by other applications. The tool was tested in a university environment in real-life situations and has produced promising results in obtaining an occupancy count.<\/jats:p>","DOI":"10.3390\/s20143916","type":"journal-article","created":{"date-parts":[[2020,7,14]],"date-time":"2020-07-14T11:03:23Z","timestamp":1594724603000},"page":"3916","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["A Tool to Calculate the Level of Occupancy in Indoor and Outdoor Spaces Using BLE and Open Data to Be Published in Real-Time"],"prefix":"10.3390","volume":"20","author":[{"given":"Montserrat","family":"Mateos S\u00e1nchez","sequence":"first","affiliation":[{"name":"Faculty of Computer Science, Universidad Pontificia de Salamanca, 37002 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0503-9134","authenticated-orcid":false,"given":"Roberto","family":"Berj\u00f3n Gallinas","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science, Universidad Pontificia de Salamanca, 37002 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6280-7852","authenticated-orcid":false,"given":"M. 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