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This protocol aims to ensure that the measurement and processing phases are performed effectively, to obtain clean data that can be used to estimate the users\u2019 anxiety levels. The protocol has been designed after analyzing the experimental data of seven subjects who have been exposed to heights in a virtual reality environment. The subjects\u2019 level of anxiety has been estimated based on the real-time evaluation of a nonlinear function that has as parameters various features extracted from the biophysical signals. The highest classification accuracy was obtained using a combination of seven heart rate and electrodermal activity features in the time domain and frequency domain.<\/jats:p>","DOI":"10.3390\/s20247088","type":"journal-article","created":{"date-parts":[[2020,12,10]],"date-time":"2020-12-10T20:18:22Z","timestamp":1607631502000},"page":"7088","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":62,"title":["Integrating Biosignals Measurement in Virtual Reality Environments for Anxiety Detection"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9264-1603","authenticated-orcid":false,"given":"Livia","family":"Petrescu","sequence":"first","affiliation":[{"name":"Faculty of Biology, University of Bucharest, 050095 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7867-1117","authenticated-orcid":false,"given":"C\u0103t\u0103lin","family":"Petrescu","sequence":"additional","affiliation":[{"name":"Faculty of Automatic Control and Computers, University Politehnica of Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6822-2684","authenticated-orcid":false,"given":"Oana","family":"Mitru\u021b","sequence":"additional","affiliation":[{"name":"Faculty of Automatic Control and Computers, University Politehnica of Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3842-9828","authenticated-orcid":false,"given":"Gabriela","family":"Moise","sequence":"additional","affiliation":[{"name":"Faculty of Letters and Sciences, Petroleum-Gas University of Ploiesti, 100680 Ploiesti, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1368-7249","authenticated-orcid":false,"given":"Alin","family":"Moldoveanu","sequence":"additional","affiliation":[{"name":"Faculty of Automatic Control and Computers, University Politehnica of Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8357-5840","authenticated-orcid":false,"given":"Florica","family":"Moldoveanu","sequence":"additional","affiliation":[{"name":"Faculty of Automatic Control and Computers, University Politehnica of Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marius","family":"Leordeanu","sequence":"additional","affiliation":[{"name":"Faculty of Automatic Control and Computers, University Politehnica of Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Fairclough, S.H. 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