{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,3]],"date-time":"2026-01-03T06:46:23Z","timestamp":1767422783706,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,7]],"date-time":"2021-07-07T00:00:00Z","timestamp":1625616000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/136815\/2018","COMPETE2020"],"award-info":[{"award-number":["SFRH\/BD\/136815\/2018","COMPETE2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007689","name":"Universidade de Aveiro","doi-asserted-by":"publisher","award":["UIDB\/00127\/2020"],"award-info":[{"award-number":["UIDB\/00127\/2020"]}],"id":[{"id":"10.13039\/100007689","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Electrocardiographic (ECG) signals have been used for clinical purposes for a long time. Notwithstanding, they may also be used as the input for a biometric identification system. Several studies, as well as some prototypes, are already based on this principle. One of the methods already used for biometric identification relies on a measure of similarity based on the Kolmogorov Complexity, called the Normalized Relative Compression (NRC)\u2014this approach evaluates the similarity between two ECG segments without the need to delineate the signal wave. This methodology is the basis of the present work. We have collected a dataset of ECG signals from twenty participants on two different sessions, making use of three different kits simultaneously\u2014one of them using dry electrodes, placed on their fingers; the other two using wet sensors placed on their wrists and chests. The aim of this work was to study the influence of the ECG protocol collection, regarding the biometric identification system\u2019s performance. Several variables in the data acquisition are not controllable, so some of them will be inspected to understand their influence in the system. Movement, data collection point, time interval between train and test datasets and ECG segment duration are examples of variables that may affect the system, and they are studied in this paper. Through this study, it was concluded that this biometric identification system needs at least 10 s of data to guarantee that the system learns the essential information. It was also observed that \u201coff-the-person\u201d data acquisition led to a better performance over time, when compared to \u201con-the-person\u201d places.<\/jats:p>","DOI":"10.3390\/s21144645","type":"journal-article","created":{"date-parts":[[2021,7,7]],"date-time":"2021-07-07T12:31:25Z","timestamp":1625661085000},"page":"4645","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["On the Impact of the Data Acquisition Protocol on ECG Biometric Identification"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9535-6445","authenticated-orcid":false,"given":"Mariana S.","family":"Ramos","sequence":"first","affiliation":[{"name":"Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9829-7804","authenticated-orcid":false,"given":"Jo\u00e3o M.","family":"Carvalho","sequence":"additional","affiliation":[{"name":"Department of Electronics Telecommunications and Informatics, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"IEETA-Institute of Electronics and Informatics Engineering of Aveiro, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9164-0016","authenticated-orcid":false,"given":"Armando J.","family":"Pinho","sequence":"additional","affiliation":[{"name":"Department of Electronics Telecommunications and Informatics, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"IEETA-Institute of Electronics and Informatics Engineering of Aveiro, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8650-9219","authenticated-orcid":false,"given":"Susana","family":"Br\u00e1s","sequence":"additional","affiliation":[{"name":"Department of Electronics Telecommunications and Informatics, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"IEETA-Institute of Electronics and Informatics Engineering of Aveiro, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1812","DOI":"10.1109\/TIFS.2012.2215324","article-title":"ECG Biometric Recognition: A Comparative Analysis","volume":"7","author":"Odinaka","year":"2012","journal-title":"IEEE Trans. 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