{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,7]],"date-time":"2025-11-07T09:30:00Z","timestamp":1762507800204,"version":"build-2065373602"},"reference-count":58,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,8,10]],"date-time":"2019-08-10T00:00:00Z","timestamp":1565395200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Mental workload assessment is crucial in many real life applications which require constant attention and where imbalance of mental workload resources may cause safety hazards. As such, mental workload and its relationship with heart rate variability (HRV) have been well studied in the literature. However, the majority of the developed models have assumed individuals are not ambulant, thus bypassing the issue of movement-related electrocardiography (ECG) artifacts and changing heart beat dynamics due to physical activity. In this work, multi-scale features for mental workload assessment of ambulatory users is explored. ECG data was sampled from users while they performed different types and levels of physical activity while performing the multi-attribute test battery (MATB-II) task at varying difficulty levels. Proposed features are shown to outperform benchmark ones and further exhibit complementarity when used in combination. Indeed, results show gains over the benchmark HRV measures of     24.41 %     in accuracy and of     27.97 %     in F1 score can be achieved even at high activity levels.<\/jats:p>","DOI":"10.3390\/e21080783","type":"journal-article","created":{"date-parts":[[2019,8,13]],"date-time":"2019-08-13T04:31:21Z","timestamp":1565670681000},"page":"783","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Multi-Scale Heart Beat Entropy Measures for Mental Workload Assessment of Ambulant Users"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8352-6152","authenticated-orcid":false,"given":"Abhishek","family":"Tiwari","sequence":"first","affiliation":[{"name":"Institut National de la Research Scientifique, Universit\u00e9 du Qu\u00e9bec, Montr\u00e9al, QC H3A 0E7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabela","family":"Albuquerque","sequence":"additional","affiliation":[{"name":"Institut National de la Research Scientifique, Universit\u00e9 du Qu\u00e9bec, Montr\u00e9al, QC H3A 0E7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mark","family":"Parent","sequence":"additional","affiliation":[{"name":"Institut National de la Research Scientifique, Universit\u00e9 du Qu\u00e9bec, Montr\u00e9al, QC H3A 0E7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Fran\u00e7ois","family":"Gagnon","sequence":"additional","affiliation":[{"name":"Thales Research and Technology, Qu\u00e9bec, QC G1P 4P5, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"Lafond","sequence":"additional","affiliation":[{"name":"Thales Research and Technology, Qu\u00e9bec, QC G1P 4P5, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S\u00e9bastien","family":"Tremblay","sequence":"additional","affiliation":[{"name":"School of Psychology, Universit\u00e9 Laval, Qu\u00e9bec, QC G1V 0A6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tiago","family":"H. Falk","sequence":"additional","affiliation":[{"name":"Institut National de la Research Scientifique, Universit\u00e9 du Qu\u00e9bec, Montr\u00e9al, QC H3A 0E7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,10]]},"reference":[{"key":"ref_1","unstructured":"Boff, K., Kaufman, L., and Thomas, J. (1986). Handbook of Perception and Human Performance, Wiley-Interscience."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1177\/001872089303500303","article-title":"Experimental evaluation of a model of mental workload","volume":"35","author":"Hancock","year":"1993","journal-title":"Hum. Factors"},{"key":"ref_3","unstructured":"Sheridan, T.B., and Simpson, R. (1979). Toward the Definition and Measurement of the Mental Workload of Transport Pilots, Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, Flight Transportation Laboratory. 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