{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,22]],"date-time":"2025-12-22T16:38:50Z","timestamp":1766421530663,"version":"3.48.0"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,22]],"date-time":"2025-12-22T00:00:00Z","timestamp":1766361600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004731","name":"Natural Science Foundation of Zhejiang Province","doi-asserted-by":"publisher","award":["LY21E080008"],"award-info":[{"award-number":["LY21E080008"]}],"id":[{"id":"10.13039\/501100004731","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005315","name":"Natural Science Foundation of Ningbo","doi-asserted-by":"publisher","award":["202003N4146"],"award-info":[{"award-number":["202003N4146"]}],"id":[{"id":"10.13039\/501100005315","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["72371154"],"award-info":[{"award-number":["72371154"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Systems"],"abstract":"<jats:p>Urban metro systems face increasing pressure to reconcile passenger service quality with infrastructure maintenance demands during late-night operations. This study proposes a coordinated optimization framework that integrates train timetabling with a flexible and selective skip-stop strategy. A mixed-integer programming model is formulated to jointly maximize passenger Origin\u2013Destination (OD) accessibility and extend available maintenance windows. To solve the high-dimensional and computationally intensive model efficiently, a hybrid GWO-CNN algorithm is designed, where a Convolutional Neural Network (CNN)-based surrogate model replaces the time-consuming fitness evaluation process in the Grey Wolf Optimizer (GWO). A real-world case study on the Beijing metro network demonstrates that the proposed method increases OD accessibility by 23.60% and extends maintenance window by 8310 s. Compared to the conventional GWO, the GWO-CNN algorithm achieves superior solution quality with a 98.4% reduction in computation time. Sensitivity analyses further reveal the trade-offs between skip-stop rates, objective weight settings, and optimization outcomes, offering practical insights for metro operators in tailoring late-night scheduling strategies to both passenger demand and maintenance priorities.<\/jats:p>","DOI":"10.3390\/systems14010011","type":"journal-article","created":{"date-parts":[[2025,12,22]],"date-time":"2025-12-22T16:19:26Z","timestamp":1766420366000},"page":"11","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Coordinated Optimization of Late-Night Metro Timetables with Selective Skip-Stop Strategy: A Hybrid GWO-CNN Approach Balancing OD Accessibility and Maintenance Needs"],"prefix":"10.3390","volume":"14","author":[{"given":"Zhiwei","family":"Wang","sequence":"first","affiliation":[{"name":"School of Maritime and Transportation, Ningbo University, Ningbo 315211, China"}]},{"given":"Shanqing","family":"Hu","sequence":"additional","affiliation":[{"name":"School of Maritime and Transportation, Ningbo University, Ningbo 315211, China"}]},{"given":"Zilu","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Maritime and Transportation, Ningbo University, Ningbo 315211, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2688-082X","authenticated-orcid":false,"given":"Xuan","family":"Li","sequence":"additional","affiliation":[{"name":"School of Maritime and Transportation, Ningbo University, Ningbo 315211, China"}]},{"given":"Zhaodong","family":"Huang","sequence":"additional","affiliation":[{"name":"School of Maritime and Transportation, Ningbo University, Ningbo 315211, China"}]},{"given":"Hanchuan","family":"Pan","sequence":"additional","affiliation":[{"name":"School of Economics & Management, Tongji University, Shanghai 200092, China"},{"name":"School of Urban Rail Transportation, Shanghai University of Engineering Science, Shanghai 201620, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,22]]},"reference":[{"key":"ref_1","unstructured":"Ma, Y., Wang, H., and Yang, H. 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