{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:19:47Z","timestamp":1760239187725,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,10,21]],"date-time":"2020-10-21T00:00:00Z","timestamp":1603238400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["01UL1712X"],"award-info":[{"award-number":["01UL1712X"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Portugal 2020 under the Competitiveness and Internationalization Operational Program, and the European Regional Development Fund through project SOCA -- Smart Open Campus","award":["CENTRO-01-0145-FEDER-000010"],"award-info":[{"award-number":["CENTRO-01-0145-FEDER-000010"]}]},{"name":"Portugal 2020 under the Competitiveness and Internationalization Operational Program, and the European Regional Development Fund through project MEMNON","award":["POCI-01\\--0145-FEDER\\--028976"],"award-info":[{"award-number":["POCI-01\\--0145-FEDER\\--028976"]}]},{"name":"IEETA Research Unit Funding","award":["UID\/CEC\/00127\/2019"],"award-info":[{"award-number":["UID\/CEC\/00127\/2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>Technologies, such as real-time magnetic resonance (RT-MRI), can provide valuable information to evolve our understanding of the static and dynamic aspects of speech by contributing to the determination of which articulators are essential (critical) in producing specific sounds and how (gestures). While a visual analysis and comparison of imaging data or vocal tract profiles can already provide relevant findings, the sheer amount of available data demands and can strongly profit from unsupervised data-driven approaches. Recent work, in this regard, has asserted the possibility of determining critical articulators from RT-MRI data by considering a representation of vocal tract configurations based on landmarks placed on the tongue, lips, and velum, yielding meaningful results for European Portuguese (EP). Advancing this previous work to obtain a characterization of EP sounds grounded on Articulatory Phonology, important to explore critical gestures and advance, for example, articulatory speech synthesis, entails the consideration of a novel set of tract variables. To this end, this article explores critical variable determination considering a vocal tract representation aligned with Articulatory Phonology and the Task Dynamics framework. The overall results, obtained considering data for three EP speakers, show the applicability of this approach and are consistent with existing descriptions of EP sounds.<\/jats:p>","DOI":"10.3390\/info11100491","type":"journal-article","created":{"date-parts":[[2020,10,21]],"date-time":"2020-10-21T10:14:22Z","timestamp":1603275262000},"page":"491","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Data-Driven Critical Tract Variable Determination for European Portuguese"],"prefix":"10.3390","volume":"11","author":[{"given":"Samuel","family":"Silva","sequence":"first","affiliation":[{"name":"Telecomunications and Informatics (DETI), Department of Electronics, Institute of Electronics and Informatics Engineering of Aveiro (IEETA), University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9742-5587","authenticated-orcid":false,"given":"Nuno","family":"Almeida","sequence":"additional","affiliation":[{"name":"Telecomunications and Informatics (DETI), Department of Electronics, Institute of Electronics and Informatics Engineering of Aveiro (IEETA), University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Concei\u00e7\u00e3o","family":"Cunha","sequence":"additional","affiliation":[{"name":"Institute of Phonetics and Speech Processing, Ludwig-Maximilians-Universit\u00e4t M\u00fcnchen, 80333 M\u00fcnchen, Germany"}]},{"given":"Arun","family":"Joseph","sequence":"additional","affiliation":[{"name":"Max Planck Institute for Biophysical Chemistry, 37077 G\u00f6ttingen, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8279-884X","authenticated-orcid":false,"given":"Jens","family":"Frahm","sequence":"additional","affiliation":[{"name":"Max Planck Institute for Biophysical Chemistry, 37077 G\u00f6ttingen, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7675-1236","authenticated-orcid":false,"given":"Ant\u00f3nio","family":"Teixeira","sequence":"additional","affiliation":[{"name":"Telecomunications and Informatics (DETI), Department of Electronics, Institute of Electronics and Informatics Engineering of Aveiro (IEETA), University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"380","DOI":"10.1123\/mcj.14.3.380","article-title":"Temporal organization of complex onsets and codas in American English: Testing the predictions of a gestural coupling model","volume":"14","author":"Marin","year":"2010","journal-title":"Mot. 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