{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T14:45:24Z","timestamp":1781534724671,"version":"3.54.5"},"reference-count":46,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T00:00:00Z","timestamp":1776384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"key Science and Technology Program of Henan Province","award":["262102211079"],"award-info":[{"award-number":["262102211079"]}]},{"name":"key Science and Technology Program of Henan Province","award":["262102211027"],"award-info":[{"award-number":["262102211027"]}]},{"name":"key Science and Technology Program of Henan Province","award":["252102210139"],"award-info":[{"award-number":["252102210139"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["82370513"],"award-info":[{"award-number":["82370513"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62476255"],"award-info":[{"award-number":["62476255"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["82370513"],"award-info":[{"award-number":["82370513"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["62476255"],"award-info":[{"award-number":["62476255"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Research and Application of Key Technologies for High-Precision Large Dynamic Unmanned Aerial Vehicle Power Inspection Electro-Optical Pod","award":["252102210002"],"award-info":[{"award-number":["252102210002"]}]},{"name":"Key Science Research Project of Colleges and Universities in Henan Province of China","award":["25A520003"],"award-info":[{"award-number":["25A520003"]}]},{"name":"Post-Doctoral Foundation of Henan Province","award":["HN2025151"],"award-info":[{"award-number":["HN2025151"]}]},{"name":"Zhengzhou Youth Science and Technology Talent Program","award":["20248651"],"award-info":[{"award-number":["20248651"]}]},{"name":"Postgraduate Education Reform and Quality Improvement Project of Henan Province","award":["YJS2023JD67"],"award-info":[{"award-number":["YJS2023JD67"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>Imaginary handwriting is an important research paradigm in the field of brain-controlled typing. Neural signals exhibit high complexity, low signal-to-noise ratio, and strong temporal and environmental variability, leading to significant inter-trial differences in the temporal dynamics of character-related signals. These factors pose significant challenges for segmenting character-related signals and accurately decoding imaginary handwriting. To address these issues, this study proposes a Dynamic Time Warping Independent Component Analysis (DTWICA) framework. This framework employs FastDTW to construct individualized warping functions for each trial, followed by FastICA-based decomposition to separate the signal into distinct temporal and neuronal factors. The decomposed temporal factors are then mapped and transformed using the warping function and subsequently merged with the neuronal factors to reconstruct the signal. A sliding time window is then applied for adaptive processing, yielding the transformed signal. Finally, the transformed signals from multiple trials are averaged to generate a template for each character. Results based on a publicly available neural signals dataset for imaginary handwriting indicate that, compared with mainstream time warping models such as Shift, Linear, Piecewise, and TWPCA, the proposed model improves the character decoding accuracy for 31 characters by 14%, 13%, 7%, and 2%, respectively. This study not only constructs effective character signal templates but also facilitates accurate character segmentation during unlabeled imagined typing in an offline setting, providing a promising methodological basis for future real-time imagined typing decoding systems.<\/jats:p>","DOI":"10.3390\/info17040379","type":"journal-article","created":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T10:11:04Z","timestamp":1776420664000},"page":"379","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["DTWICA: A Novel Method for Constructing Character Templates in Imaginary Handwriting"],"prefix":"10.3390","volume":"17","author":[{"given":"Jiaofen","family":"Nan","sequence":"first","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Panpan","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"},{"name":"Faculty of Engineering, Huanghe Science and Technology College, Zhengzhou 450000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gaodeng","family":"Fan","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xueqi","family":"Jin","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuyao","family":"Zhai","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanting","family":"Li","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongquan","family":"Xia","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4100-3908","authenticated-orcid":false,"given":"Yinghui","family":"Meng","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liqin","family":"Yue","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Huanghe Science and Technology College, Zhengzhou 450000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4520-8748","authenticated-orcid":false,"given":"Duan","family":"Li","sequence":"additional","affiliation":[{"name":"School of Computer Science and Artificial Intelligence, Zhengzhou University of Light Industry, Zhengzhou 450001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1308","DOI":"10.1136\/jnnp.57.11.1308","article-title":"Electroencephalography","volume":"57","author":"Binnie","year":"1994","journal-title":"J. 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