{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T18:49:54Z","timestamp":1764874194262,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,1]],"date-time":"2025-05-01T00:00:00Z","timestamp":1746057600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea","award":["NRF-2021R1I1A2045721"],"award-info":[{"award-number":["NRF-2021R1I1A2045721"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Systems"],"abstract":"<jats:p>The air-handling unit (AHU) is an essential component of heating, ventilation, and air-conditioning (HVAC) systems. Hence, detecting the faults in AHUs is essential for maintaining continuous HVAC operation and preventing system breakdowns. The advent of artificial intelligence has transformed the AHU fault diagnosis techniques. Specifically, deep learning has obviated the necessity for manual feature extraction and selection, thereby streamlining the fault diagnosis process. While conventional convolutional neural networks (CNNs) effectively detect defects, incorporating more spatial variables could enhance their performance further. This paper presents a hybrid architecture combining a CNN model with a long short-term memory (LSTM) model to diagnose the faults in AHUs. The advantages of the LSTM model and convolutional layers are combined to identify significant patterns in the input data, which considerably facilitates the detection of AHU defects. The hybrid design enhances the network\u2019s capability to capture both local and global characteristics, thus improving its ability to differentiate between normal and abnormal circumstances. The proposed approach achieves strong diagnostic accuracy, exhibiting high sensitivity to nuanced fault patterns. Furthermore, its efficacy is corroborated through comparisons with state-of-the-art AHU fault identification techniques.<\/jats:p>","DOI":"10.3390\/systems13050330","type":"journal-article","created":{"date-parts":[[2025,5,1]],"date-time":"2025-05-01T09:16:12Z","timestamp":1746090972000},"page":"330","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Fault Detection and Diagnosis in Air-Handling Unit (AHU) Using Improved Hybrid 1D Convolutional Neural Network"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5878-7227","authenticated-orcid":false,"family":"Prince","sequence":"first","affiliation":[{"name":"Department of Industrial & Systems Engineering, Dongguk University, Seoul 04620, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1110-4011","authenticated-orcid":false,"given":"Byungun","family":"Yoon","sequence":"additional","affiliation":[{"name":"Department of Industrial & Systems Engineering, Dongguk University, Seoul 04620, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6353-6302","authenticated-orcid":false,"given":"Prashant","family":"Kumar","sequence":"additional","affiliation":[{"name":"Department of of AI and Big Data, Woosong University, Daejeon 34606, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100002","DOI":"10.1016\/j.prime.2021.100002","article-title":"Present and future energy consumption of buildings: Challenges and opportunities towards decarbonisation","volume":"1","author":"Santamouris","year":"2021","journal-title":"e-Prime\u2014Adv. 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