{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T05:02:23Z","timestamp":1785301343071,"version":"3.55.0"},"reference-count":47,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T00:00:00Z","timestamp":1785110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100017596","name":"Natural Science Basic Research Program of Shaanxi Province","doi-asserted-by":"crossref","award":["2023-JC-ZD-38"],"award-info":[{"award-number":["2023-JC-ZD-38"]}],"id":[{"id":"10.13039\/501100017596","id-type":"DOI","asserted-by":"crossref"}]},{"name":"National Key Research and Development Project","award":["2022YFB3305503"],"award-info":[{"award-number":["2022YFB3305503"]}]},{"name":"Key Science and Technology Project of Henan Province","award":["201300210400"],"award-info":[{"award-number":["201300210400"]}]},{"name":"Key Research and Development Program of Shaanxi Province","award":["2023-YBGY-403"],"award-info":[{"award-number":["2023-YBGY-403"]}]},{"name":"Provincial College Students\u2019 Innovation and Entrepreneurship Training Program of Shaanxi Province","award":["S202510709094"],"award-info":[{"award-number":["S202510709094"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Real-time classroom behavior monitoring is an important component of intelligent education systems, yet it remains challenging due to dense student layouts, frequent occlusions, and small-scale behavior targets. To address these challenges, this paper proposes Hierarchical Adaptive Re-parameterized Multi-scale YOLO11n (HARM-YOLO11n), a lightweight object detection framework based on YOLO11n for classroom behavior analysis. The proposed framework integrates structural re-parameterized feature enhancement (SRFE), a spatial-channel adaptive module (SCAM), position-adaptive multi-scale fusion (PAMSF), and IoU-adaptive soft weight (IASW) to improve feature representation, multi-scale interaction, and optimization behavior. SRFE enhances feature extraction through structural re-parameterization, the SCAM reduces redundant feature responses via selective spatial-channel computation, PAMSF performs adaptive multi-scale feature aggregation, and IASW introduces localization-aware sample weighting during training. Experiments on POCO-Dataset, SCB-Dataset3, and STBD-08 show that HARM-YOLO11n achieves improved detection performance compared with representative lightweight detectors while maintaining real-time inference efficiency. Multi-dataset evaluations further indicate stable performance under different data distributions. The results suggest that the proposed framework provides a practical approach for classroom behavior detection in resource-constrained educational environments.<\/jats:p>","DOI":"10.3390\/s26154770","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T11:54:26Z","timestamp":1785153266000},"page":"4770","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["HARM-YOLO11n: A Lightweight Real-Time Object Detection Framework for Robust Classroom Behavior Monitoring"],"prefix":"10.3390","volume":"26","author":[{"given":"Zihang","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Computer Science, Xi\u2019an Polytechnic University, Xi\u2019an 710048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7450-408X","authenticated-orcid":false,"given":"Yonghua","family":"Mao","sequence":"additional","affiliation":[{"name":"School of Computer Science, Xi\u2019an Polytechnic University, Xi\u2019an 710048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingcang","family":"Ma","sequence":"additional","affiliation":[{"name":"School of Science, Xi\u2019an Polytechnic University, Xi\u2019an 710048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4384-9891","authenticated-orcid":false,"given":"Xiaolin","family":"Gui","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1186\/s40561-016-0026-2","article-title":"A Research Framework of Smart Education","volume":"3","author":"Zhu","year":"2016","journal-title":"Smart Learn. 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