{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T12:55:10Z","timestamp":1783688110250,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,15]],"date-time":"2020-06-15T00:00:00Z","timestamp":1592179200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007224","name":"National Foundation for Science and Technology Development","doi-asserted-by":"publisher","award":["107.01-2019.332"],"award-info":[{"award-number":["107.01-2019.332"]}],"id":[{"id":"10.13039\/100007224","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, we investigate a novel idea of using synthetic images of bolts which are generated from a graphical model to train a deep learning model for loosened bolt detection. Firstly, a framework for bolt-loosening detection using image-based deep learning and computer graphics is proposed. Next, the feasibility of the proposed framework is demonstrated through the bolt-loosening monitoring of a lab-scaled bolted joint model. For practicality, the proposed idea is evaluated on the real-scale bolted connections of a historical truss bridge in Danang, Vietnam. The results show that the deep learning model trained by the synthesized images can achieve accurate bolt recognitions and looseness detections. The proposed methodology could help to reduce the time and cost associated with the collection of high-quality training data and further accelerate the applicability of vision-based deep learning models trained on synthetic data in practice.<\/jats:p>","DOI":"10.3390\/s20123382","type":"journal-article","created":{"date-parts":[[2020,6,15]],"date-time":"2020-06-15T12:16:57Z","timestamp":1592223417000},"page":"3382","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":79,"title":["Bolt-Loosening Monitoring Framework Using an Image-Based Deep Learning and Graphical Model"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7830-7967","authenticated-orcid":false,"given":"Hai Chien","family":"Pham","sequence":"first","affiliation":[{"name":"Applied Computational Civil and Structural Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7421-3875","authenticated-orcid":false,"given":"Quoc-Bao","family":"Ta","sequence":"additional","affiliation":[{"name":"Ocean Engineering Department, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeong-Tae","family":"Kim","sequence":"additional","affiliation":[{"name":"Ocean Engineering Department, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9081-1338","authenticated-orcid":false,"given":"Duc-Duy","family":"Ho","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering, Ho Chi Minh City University of Technology (HCMUT), Ho Chi Minh City 700000, Vietnam"},{"name":"Vietnam National University, Ho Chi Minh City 700000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuan-Linh","family":"Tran","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering, Duy Tan University, Danang 550000, Vietnam"},{"name":"Center for Construction, Mechanics and Materials, Institute of Research and Development, Duy Tan University, Danang 550000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9231-2129","authenticated-orcid":false,"given":"Thanh-Canh","family":"Huynh","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering, Duy Tan University, Danang 550000, Vietnam"},{"name":"Center for Construction, Mechanics and Materials, Institute of Research and Development, Duy Tan University, Danang 550000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"871213","DOI":"10.1155\/2013\/871213","article-title":"Review of Bolted Connection Monitoring","volume":"9","author":"Wang","year":"2013","journal-title":"Int. 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