{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T13:27:39Z","timestamp":1781530059430,"version":"3.54.1"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,31]],"date-time":"2022-12-31T00:00:00Z","timestamp":1672444800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NATO Science for Peace and Security (SPS)","award":["G5605"],"award-info":[{"award-number":["G5605"]}]},{"name":"NATO Science for Peace and Security (SPS)","award":["G5969"],"award-info":[{"award-number":["G5969"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Counter terrorism is a huge challenge for public spaces. Therefore, it is essential to support early detection of threats, such as weapons or explosives. An integrated fusion engine was developed for the management of a plurality of sensors to detect threats without disrupting the flow of commuters. The system improves security of soft targets (such as airports, undergrounds and railway stations) by providing security operators with real-time information of the threat combined with image and position data of each person passing the monitored area. This paper describes the results of the fusion engine in a public-space trial in a metro station in Rome. The system consists of 2D-video tracking, person re-identification, 3D-video tracking, and command and control (C&amp;C) formulating two co-existing data pipelines: one for visualization on smart glasses and another for hand-over to another sensor. Over multiple days, 586 commuters participated in the trial. The results of the trial show overall accuracy scores of 97.4% and 97.6% for the visualization and hand-over pipelines, respectively, and each component reached high accuracy values (2D Video = 98.0%, Re-identification = 100.0%, 3D Video = 99.7% and C&amp;C = 99.5%).<\/jats:p>","DOI":"10.3390\/s23010440","type":"journal-article","created":{"date-parts":[[2023,1,2]],"date-time":"2023-01-02T03:08:59Z","timestamp":1672628939000},"page":"440","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["An Integrated Fusion Engine for Early Threat Detection Demonstrated in Public-Space Trials"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9363-6870","authenticated-orcid":false,"given":"Henri","family":"Bouma","sequence":"first","affiliation":[{"name":"TNO-Netherlands Organisation for Applied Scientific Research, 2597 The Hague, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7582-806X","authenticated-orcid":false,"given":"Maria Luisa","family":"Villani","sequence":"additional","affiliation":[{"name":"ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, 00123 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arthur","family":"van Rooijen","sequence":"additional","affiliation":[{"name":"TNO-Netherlands Organisation for Applied Scientific Research, 2597 The Hague, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pauli","family":"R\u00e4s\u00e4nen","sequence":"additional","affiliation":[{"name":"VTT-Technical Research Centre of Finland, 33101 Tampere, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johannes","family":"Peltola","sequence":"additional","affiliation":[{"name":"VTT-Technical Research Centre of Finland, 33101 Tampere, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3300-2718","authenticated-orcid":false,"given":"Sirra","family":"Toivonen","sequence":"additional","affiliation":[{"name":"VTT-Technical Research Centre of Finland, 33101 Tampere, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1045-0510","authenticated-orcid":false,"given":"Antonio","family":"De Nicola","sequence":"additional","affiliation":[{"name":"ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, 00123 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8041-4067","authenticated-orcid":false,"given":"Massimiliano","family":"Guarneri","sequence":"additional","affiliation":[{"name":"ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, 00123 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristiano","family":"Stifini","sequence":"additional","affiliation":[{"name":"ATAC-Azienda per la Mobilit\u00e0 di Roma Capitale S.p.A, 00176 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7358-9624","authenticated-orcid":false,"given":"Luigi","family":"De Dominicis","sequence":"additional","affiliation":[{"name":"ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, 00123 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,31]]},"reference":[{"key":"ref_1","first-page":"453","article-title":"Terrorist Attacks on Selected Soft Targets","volume":"8","year":"2019","journal-title":"J. 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