{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:14:01Z","timestamp":1785428041199,"version":"3.56.0"},"reference-count":29,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T00:00:00Z","timestamp":1782172800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004242","name":"Princess Nourah bint Abdulrahman University","doi-asserted-by":"crossref","award":["PNURSP2026R239"],"award-info":[{"award-number":["PNURSP2026R239"]}],"id":[{"id":"10.13039\/501100004242","id-type":"DOI","asserted-by":"crossref"}]},{"award":["PNURSP2026R239"],"award-info":[{"award-number":["PNURSP2026R239"]}],"id":[{"id":"https:\/\/ror.org\/05b0cyh02","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Indoor air quality has a significant impact on occupant health, comfort, and productivity in residential and commercial indoor environments. This paper proposes an IoT-edge enabled deep\u2013fuzzy hybrid framework for real-time IAQ prediction and adaptive control. The proposed system integrates IoT-based environmental sensing, Temporal Fusion Transformer-based multivariate forecasting, knowledge distillation, edge-deployed Bi-LSTM inference, and Mamdani fuzzy logic control within a unified IAQ management architecture. A composite Comfort Risk Index is introduced to combine environmental parameters and occupant discomfort feedback into a single adaptive control indicator. Experimental evaluation under varying indoor conditions demonstrated strong forecasting performance, with prediction accuracies reaching 96.3% for CO2 and 95.7% for PM2.5 prediction, while reducing inference latency from 575 ms to 295 ms. Comparative analysis against baseline threshold-based control strategies further indicated improved comfort stability, smoother actuator behavior, and reduced estimated actuator operating intensity during deployment. The proposed framework also demonstrated resilient operation under simulated sensor-failure conditions while maintaining low computational overhead suitable for resource-constrained IoT-edge environments. Overall, the results indicate that combining lightweight deep learning models with interpretable fuzzy control can provide an effective, scalable, and energy-aware solution for intelligent real-time IAQ optimization in smart indoor environments.<\/jats:p>","DOI":"10.3390\/s26133989","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T01:03:23Z","timestamp":1782263003000},"page":"3989","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["An IoT-Edge Enabled Deep\u2013Fuzzy Hybrid Model for Real-Time Indoor Air Quality Optimization"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9711-0235","authenticated-orcid":false,"given":"Samia Allaoua","family":"Chelloug","sequence":"first","affiliation":[{"name":"Department of Information Technology, College of Computer and Information Sciences, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1165-7812","authenticated-orcid":false,"given":"Mohammed","family":"Muthanna","sequence":"additional","affiliation":[{"name":"Faculty of Computing and Information Technology, Sohar University, Sohar 311, Oman"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah","family":"Alshahrani","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Artificial Intelligence, College of Computer Science and Engineering, University of Jeddah, Jeddah 21493, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-5321-077X","authenticated-orcid":false,"given":"Mohammad Hassan Ali","family":"Al-Onaizan","sequence":"additional","affiliation":[{"name":"Department of Intelligent Systems Engineering, Faculty of Engineering and Design, Middle East University, Amman 11831, Jordan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0213-8145","authenticated-orcid":false,"given":"Ammar","family":"Muthanna","sequence":"additional","affiliation":[{"name":"Institute of Computer Science and Telecommunications, RUDN University, 117198 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Faisal","family":"Jamil","sequence":"additional","affiliation":[{"name":"Department of AI and Software, Gachon University, Seongnam 13120, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1016\/j.enbuild.2016.08.071","article-title":"Indoor air quality and its effects on humans-A review of challenges and developments in the last 30 years","volume":"130","author":"Tham","year":"2016","journal-title":"Energy Build."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"178771","DOI":"10.1016\/j.scitotenv.2025.178771","article-title":"Characteristics and exposure determinants of PM2. 5, formaldehyde, and total volatile organic compounds in residential indoor air in Korea","volume":"967","author":"Park","year":"2025","journal-title":"Sci. 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