{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,26]],"date-time":"2025-12-26T07:13:50Z","timestamp":1766733230343,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2022,8,24]],"date-time":"2022-08-24T00:00:00Z","timestamp":1661299200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Major Scientific and Technological Innovation Project of Shandong Province of China","award":["2020CXGC010705","2021ZLGX05"],"award-info":[{"award-number":["2020CXGC010705","2021ZLGX05"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>At present, some related studies on semantic segmentation are becoming complicated, adding a lot of feature layers and various jump splicing to improve the level of refined segmentation, which often requires a large number of parameters to ensure a better segmentation effect. When faced with lightweight tasks, such as sea and land segmentation, the modeling capabilities of these models far exceed the complexity of the task, and reducing the size of the model can easily weaken the original effect of the model. In response to this problem, this paper proposes a U-net optimization structure combining Atrous Spatial Pyramid Pooling (ASPP) and FReLU, namely ACU-Net. ACU-Net replaces the two-layer continuous convolution in the feature extraction part of U-Net with a lightweight ASPP module, retains the symmetric U-shaped structure of the original U-Net structure, and splices the output of the ASPP module with the upsampling part. Use FReLU to improve the modeling ability between pixels, and at the same time cooperate with the attention mechanism to improve the perception ability and receptive field of the network, reduce the training difficulty of the model, and fully tap the hidden information of the samples to capture more effective features. The experimental results show that the ACU-Net in this paper surpasses the reduced U-Net and its optimized improved network U-Net++ in terms of segmentation accuracy and IoU with a smaller volume.<\/jats:p>","DOI":"10.3390\/rs14174163","type":"journal-article","created":{"date-parts":[[2022,8,24]],"date-time":"2022-08-24T23:48:58Z","timestamp":1661384938000},"page":"4163","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Sea and Land Segmentation of Optical Remote Sensing Images Based on U-Net Optimization"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6893-9028","authenticated-orcid":false,"given":"Jianfeng","family":"Li","sequence":"first","affiliation":[{"name":"School of Information Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhenghong","family":"Huang","sequence":"additional","affiliation":[{"name":"School of Information Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongling","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Information Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0168-1245","authenticated-orcid":false,"given":"Qinghua","family":"Luo","sequence":"additional","affiliation":[{"name":"School of Information Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,24]]},"reference":[{"key":"ref_1","first-page":"41","article-title":"Review on Image Semantic Segmentation Based on Fully Convolutional Network","volume":"3","author":"Li","year":"2021","journal-title":"Comput. 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