{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:31:49Z","timestamp":1760059909166,"version":"build-2065373602"},"reference-count":54,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,7,21]],"date-time":"2025-07-21T00:00:00Z","timestamp":1753056000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["12426308","2023YFA1011402"],"award-info":[{"award-number":["12426308","2023YFA1011402"]}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["12426308","2023YFA1011402"],"award-info":[{"award-number":["12426308","2023YFA1011402"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Beijing Postdoctoral Research Foundation and the Key Research Project of the Academy for Multidisciplinary Studies, Capital Normal University","award":["12426308","2023YFA1011402"],"award-info":[{"award-number":["12426308","2023YFA1011402"]}]},{"name":"National Center for Applied Mathematics Beijing","award":["12426308","2023YFA1011402"],"award-info":[{"award-number":["12426308","2023YFA1011402"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Spectral computed tomography (SCT) enables material decomposition, artifact reduction, and contrast enhancement, leveraging symmetry principles across its technical framework to enhance material differentiation and image quality. However, its nonlinear data acquisition process involving noise and scatter leads to a highly ill-posed inverse problem. To address this, we propose a dual-domain iterative reconstruction network that combines joint learning reconstruction with physical process modeling, which also uses the symmetric complementary properties of the two domains for optimization. A dedicated physical module models the SCT forward process to ensure stability and accuracy, while a residual-to-residual strategy reduces the computational burden of model-based iterative reconstruction (MBIR). Our method, which won the AAPM DL-Spectral CT Challenge, achieves high-accuracy material decomposition. Extensive evaluations also demonstrate its robustness under varying noise levels, confirming the method\u2019s generalizability. This integrated approach effectively combines the strengths of physical modeling, MBIR, and deep learning.<\/jats:p>","DOI":"10.3390\/sym17071165","type":"journal-article","created":{"date-parts":[[2025,7,21]],"date-time":"2025-07-21T13:59:11Z","timestamp":1753106351000},"page":"1165","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Dual-Domain Joint Learning Reconstruction Method (JLRM) Combined with Physical Process for Spectral Computed Tomography (SCT)"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3997-1106","authenticated-orcid":false,"given":"Genwei","family":"Ma","sequence":"first","affiliation":[{"name":"Academy for Multidisciplinary Studies, Capital Normal University, No. 105 West Third Ring Road North, Beijing 100048, China"},{"name":"National Center for Applied Mathematics Beijing, Capital Normal University, No. 105 West Third Ring Road North, Beijing 100048, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9696-5346","authenticated-orcid":false,"given":"Ping","family":"Yang","sequence":"additional","affiliation":[{"name":"Institute of Nuclear and New Energy Technology, Tsinghua University, Haidian District, Beijing 100084, China"},{"name":"School of Mathematical Sciences, Capital Normal University, No. 105 West Third Ring Road North, Beijing 100048, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xing","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Mathematical Sciences, Capital Normal University, No. 105 West Third Ring Road North, Beijing 100048, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,21]]},"reference":[{"key":"ref_1","first-page":"1198","article-title":"Dual energy CT via fast kVp switching spectrum estimation","volume":"Volume 7258","author":"Xu","year":"2009","journal-title":"Medical Imaging 2009: Physics of Medical Imaging"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1016\/j.ejrad.2008.08.013","article-title":"Technical principles of dual source CT","volume":"68","author":"Petersilka","year":"2008","journal-title":"Eur. 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