{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T20:52:33Z","timestamp":1774385553542,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,3]],"date-time":"2021-11-03T00:00:00Z","timestamp":1635897600000},"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>The advancement of sensing technologies coupled with the rapid progress in big data analysis has ushered in a new era in intelligent transport and smart city applications. In this context, transportation mode detection (TMD) of mobile users is a field that has gained significant traction in recent years. In this paper, we present a deep learning approach for transportation mode detection using multimodal sensor data elicited from user smartphones. The approach is based on long short-term Memory networks and Bayesian optimization of their parameters. We conducted an extensive experimental evaluation of the proposed approach, which attains very high recognition rates, against a multitude of machine learning approaches, including state-of-the-art methods. We also discuss issues regarding feature correlation and the impact of dimensionality reduction.<\/jats:p>","DOI":"10.3390\/e23111457","type":"journal-article","created":{"date-parts":[[2021,11,3]],"date-time":"2021-11-03T17:59:38Z","timestamp":1635962378000},"page":"1457","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Transportation Mode Detection Using an Optimized Long Short-Term Memory Model on Multimodal Sensor Data"],"prefix":"10.3390","volume":"23","author":[{"given":"Ifigenia","family":"Drosouli","sequence":"first","affiliation":[{"name":"Department of Informatics and Computer Engineering, University of West Attica, 12243 Athens, Greece"},{"name":"Department of Informatics, University of Limoges, 87032 Limoges, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0632-9769","authenticated-orcid":false,"given":"Athanasios","family":"Voulodimos","sequence":"additional","affiliation":[{"name":"Department of Informatics and Computer Engineering, University of West Attica, 12243 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Georgios","family":"Miaoulis","sequence":"additional","affiliation":[{"name":"Department of Informatics and Computer Engineering, University of West Attica, 12243 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paris","family":"Mastorocostas","sequence":"additional","affiliation":[{"name":"Department of Informatics and Computer Engineering, University of West Attica, 12243 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Djamchid","family":"Ghazanfarpour","sequence":"additional","affiliation":[{"name":"Department of Informatics, University of Limoges, 87032 Limoges, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Nitti, M., Pinna, F., Pintor, L., Pilloni, V., and Barabino, B. 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