{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:10:43Z","timestamp":1760148643371,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,5,26]],"date-time":"2023-05-26T00:00:00Z","timestamp":1685059200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004739","name":"Youth Innovation Promotion Association","doi-asserted-by":"publisher","award":["E1213A02","Y202045","22E0223301","41974211"],"award-info":[{"award-number":["E1213A02","Y202045","22E0223301","41974211"]}],"id":[{"id":"10.13039\/501100004739","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Key Research Program of Frontier Sciences, CAS","award":["E1213A02","Y202045","22E0223301","41974211"],"award-info":[{"award-number":["E1213A02","Y202045","22E0223301","41974211"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["E1213A02","Y202045","22E0223301","41974211"],"award-info":[{"award-number":["E1213A02","Y202045","22E0223301","41974211"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Extracting the peak value of the X-ray signal in the original magnetopause detection method of soft X-ray imaging (SXI) for the SMILE satellite is problematic because of the unclear interface of the magnetosphere system under low solar wind density and the short integration time. Herein, we propose a segmentation algorithm for soft X-ray images based on depth learning, we construct an SXI simulation dataset, and we segment the magnetospheric system by learning the spatial structure characteristics of the magnetospheric system image. Then, we extract the maximum position of the X-ray signal and calculate the spatial configuration of the magnetopause using the tangent fitting approach. Under a uniform universe condition, we achieved a pixel accuracy of the maximum position of the photon number detected by the network as high as 90.94% and contained the position error of the sunset point of the 3D magnetopause below 0.2 RE. This result demonstrates that the proposed method can detect the peak photon number of magnetospheric soft X-ray images with low solar wind density. As such, its use improves the segmentation accuracy of magnetospheric soft X-ray images and reduces the imaging time requirements of the input image.<\/jats:p>","DOI":"10.3390\/rs15112771","type":"journal-article","created":{"date-parts":[[2023,5,27]],"date-time":"2023-05-27T16:17:33Z","timestamp":1685204253000},"page":"2771","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Magnetopause Detection under Low Solar Wind Density Based on Deep Learning"],"prefix":"10.3390","volume":"15","author":[{"given":"Yujie","family":"Zhang","sequence":"first","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100094, China"},{"name":"Hangzhou Institute for Advanced Study (UCAS), Hangzhou 310012, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tianran","family":"Sun","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1643-1705","authenticated-orcid":false,"given":"Wenlong","family":"Niu","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yihong","family":"Guo","sequence":"additional","affiliation":[{"name":"Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Song","family":"Yang","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100094, China"},{"name":"Hangzhou Institute for Advanced Study (UCAS), Hangzhou 310012, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaodong","family":"Peng","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhen","family":"Yang","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,26]]},"reference":[{"key":"ref_1","first-page":"13","article-title":"SMILE Satellite mission survey","volume":"464","author":"Wang","year":"2017","journal-title":"Space Int."},{"key":"ref_2","unstructured":"Branduardi-Raymont, G., Escoubet, C.P., Kuntz, K., Lui, T., Read, A., Sibeck, D., Dai, L., Dmitriev, A., Donovan, E., and Dunlo, M. (ISSI-BJ Magazine, 2016). Link between Solar Wind, Magnetosphere, and Lonosphere, ISSI-BJ Magazine, p. 9."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1233","DOI":"10.1029\/JZ068i005p01233","article-title":"The distant geomagnetic field: 3. Disorder and shocks in the magnetopause","volume":"68","author":"Sonett","year":"1963","journal-title":"J. Geophys. Res."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1835","DOI":"10.1029\/JZ068i007p01835","article-title":"The boundary of the geo-magnetic field","volume":"68","author":"Cahill","year":"1963","journal-title":"J.Geophys. Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1126\/science.274.5285.205","article-title":"Discovery of X-ray and extreme ultraviolet emission from comet C\/Hyakutake 1996 B2","volume":"274","author":"Lisse","year":"1996","journal-title":"Science"},{"key":"ref_6","first-page":"143","article-title":"The solar wind charge-exchange production factor for hydrogen","volume":"808","author":"Kuntz","year":"2015","journal-title":"Rev. Sci. Instrum."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"Al2105","DOI":"10.1029\/2006JA011672","article-title":"X-ray emission from the terrestrial magnetosheath including the cusps","volume":"111","author":"Robertson","year":"2006","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_8","unstructured":"Dennerl, K. (2009, January 19). High Resolution X-ray Spectroscopy of Comets. Proceedings of the International Workshop, London, UK."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"558","DOI":"10.1086\/317176","article-title":"Implications of solar wind composition for cometary X-rays","volume":"544","author":"Schwadron","year":"2000","journal-title":"Astrophys. J."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"837","DOI":"10.1051\/0004-6361:200809997","article-title":"Identifying XMM-Newton observations affected by solar wind charge exchange\u2014Part I","volume":"489","author":"Carter","year":"2008","journal-title":"Astron. Astrophys."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"867","DOI":"10.1111\/j.1365-2966.2009.15985.x","article-title":"A high charge state coronal mass ejection seen through solar wind charge exchange emission as detected by XMM-Newton","volume":"402","author":"Carter","year":"2010","journal-title":"Mon. Not. R. Astron. Soc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"A115","DOI":"10.1051\/0004-6361\/201015817","article-title":"Identifying XMM-Newton observations affected by solar wind charge exchange\u2014Part II","volume":"527","author":"Carter","year":"2011","journal-title":"Astron. Astrophys."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1093\/pasj\/59.sp1.S133","article-title":"Evidence for solar-wind charge-exchange X-ray emission from the Earth\u2019s magnetosheath","volume":"59","author":"Fujimoto","year":"2007","journal-title":"Publ. Astron. Soc. Jpn."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"372","DOI":"10.1088\/0004-637X\/691\/1\/372","article-title":"Observation of solar wind charge exchange emission from exospheric material in and outside Earth\u2019s magnetosheath 2008 September 25","volume":"691","author":"Snowden","year":"2009","journal-title":"Astrophys. J."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2435","DOI":"10.1029\/2018JA026093","article-title":"Soft X-ray Imaging of the Magnetosheath and Cusps Under Different Solar Wind Conditions: MHD Simulations","volume":"124","author":"Sun","year":"2019","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"e2022JA030848","DOI":"10.1029\/2022JA030848","article-title":"Finding Magnetopause Standoff Distance using a Soft X-ray Imager\u2013Part 1, Magnetospheric masking","volume":"127","author":"Samsonov","year":"2022","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"15138","DOI":"10.1364\/OE.26.015138","article-title":"Numerical model built for the simulation of the earth magnetopause by lobster-eye-type soft X-ray imager onboard SMILE satellite","volume":"26","author":"Peng","year":"2018","journal-title":"Opt. Express."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"4365","DOI":"10.1029\/2018JA025919","article-title":"Boundary Detection in Three Dimensions with Application to the SMILE Mission: The Effect of Photon Noise","volume":"124","author":"Jorgensen","year":"2019","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4341","DOI":"10.1029\/2018JA026124","article-title":"Boundary Detection in Three Dimensions with Application to the SMILE Mission: The Effect of Model-Fitting Noise","volume":"124","author":"Jorgensen","year":"2019","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"10189","DOI":"10.1029\/2018JA025763","article-title":"Magnetopause Surface Reconstruction from Tangent Vector Observations","volume":"123","author":"Collier","year":"2018","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"e28169","DOI":"10.1029\/2020JA028169","article-title":"Deriving the Magnetopause Position from the Soft X-ray Image by Using the Tangent Fitting Approach","volume":"125","author":"Sun","year":"2020","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1601","DOI":"10.1007\/s11430-021-9937-y","article-title":"Deriving the magnetopause position from wide field-of-view soft X-ray imager simulation","volume":"65","author":"Guo","year":"2022","journal-title":"Sci. China Earth Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"e2022JA030850","DOI":"10.1029\/2022JA030850","article-title":"Finding Magnetopause Standoff Distance using a Soft X-ray Imager\u2013Part 2, Methods to Analyze 2-DX-ray Images","volume":"127","author":"Samsonov","year":"2022","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Long, J., Shelhamer, E., and Darrell, T. (2015, January 7\u201312). Fully Convolutional Networks for Semantic Segmentation. Proceedings of the 2015 IEEE Conference on Computer Vision and Pattern Recognition, Boston, MA, USA.","DOI":"10.1109\/CVPR.2015.7298965"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Ronneberger, O., Fischer, P., and Brox, T. (2015, January 5\u20139). U-Net: Convolutional Networks for Biomedical Image Segmentation. Proceedings of the International Conference on Medical Image Computing and Computer Assisted Intervention, Munich, Germany.","DOI":"10.1007\/978-3-319-24574-4_28"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2481","DOI":"10.1109\/TPAMI.2016.2644615","article-title":"SegNet: A Deep convolutional encoder-decoder architecture for image segmentation","volume":"39","author":"Badrinarayanan","year":"2017","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Zhao, H., Shi, J., Qi, X., Wang, X., and Jia, J. (2017, January 21\u201326). Pyramid scene parsing network. Proceedings of the 2017 IEEE Conference on Computer Vision and Pattern Recognition, Honolulu, HI, USA.","DOI":"10.1109\/CVPR.2017.660"},{"key":"ref_28","unstructured":"Howard, A.G., Zhu, M., Chen, B., Kalenichenko, D., Wang, W., Weyand, T., Andreetto, M., and Adam, H. (2017). Mobile Nets: Efficient convolutional neural networks for mobile vision applications. arXiv."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Sandler, M., Howard, A., Zhu, M., Zhmoginov, A., and Chen, L.C. (2018, January 18\u201323). MobileNetV 2, Inverted Residuals and Linear Bottlenecks. Proceedings of the 2018 IEE Conference on Computer Vision and Pattern Recognition, Salt Lake City, UT, USA.","DOI":"10.1109\/CVPR.2018.00474"},{"key":"ref_30","unstructured":"Chen, L.C., Papandreou, G., Kokkinos, I., Murphy, K., and Yuille, A.L. (2014). Semantic Image Segmentation with Deep Convolutional Nets and Fully Connected CRFs. arXiv."},{"key":"ref_31","unstructured":"Simonyan, K., and Zisseman, A. (2014). VeryDeep Convolutional Net-works for Large-scale Image Recognition [EB\/OL]. arXiv."},{"key":"ref_32","unstructured":"Chen, L.C., Papandreou, G., Kokkinos, I., Murphy, K., and Yuille, A.L. (2016). Deeplab: Semantic image segmentation with deep convolutional nets, atrous convolution, and fully connected crfs. arXiv."},{"key":"ref_33","unstructured":"Chen, L.C., Papandreou, G., Schroff, F., and Adam, H. (2017). Rethinking atrous convolution for semantic image segmentation. arXiv."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Chen, L.C., Zhu, Y., Papandreou, G., Schroff, F., and Adam, H. (2018, January 8\u201314). Encoder-Decoder with Atrous Separable Convolution for Semantic Image Segmentation. Proceedings of the European Conference on Computer Vision (ECCV), Munich, Germany.","DOI":"10.1007\/978-3-030-01234-2_49"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"106210","DOI":"10.1016\/j.cmpb.2021.106210","article-title":"Medical image recognition and segmentation of pathological slices of gastric cancer based on Deeplab v3+ neural network","volume":"207","author":"Wang","year":"2021","journal-title":"Comput. Methods Programs Biomed."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/j.ejmp.2022.06.007","article-title":"Automatic segmentation of glioblastoma multiform brain tumor in MRI images: Using Deeplabv3+ with pre-trained Resnet18 weights","volume":"100","author":"Shoushtari","year":"2022","journal-title":"Phys. Med."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"632","DOI":"10.4283\/JMAG.2020.25.4.632","article-title":"Deeplab v3+ Based Automatic Diagnosis Model for Dental X-ray: Preliminary Study","volume":"25","author":"Jung","year":"2020","journal-title":"J. Magn."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"A07215","DOI":"10.1029\/2006JA012145","article-title":"On the ionospheric and reconnection potentials of the Earth: Results from global MHD simulations","volume":"112","author":"Hu","year":"2007","journal-title":"J. Geophys. Res."},{"key":"ref_39","first-page":"24105","article-title":"Comet Hyakutake X-ray source: Charge transfer of solar wind heavy ions","volume":"100","author":"Cravens","year":"1997","journal-title":"Geophys. Res. Lett."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"69","DOI":"10.3847\/1538-4357\/acc326","article-title":"Dynamical response of solar wind charge exchange soft X-ray emission in Earth\u2019s magnetosphere to the solar wind proton flux","volume":"948","author":"Zhang","year":"2023","journal-title":"Astrophys. J."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"L153","DOI":"10.1086\/312574","article-title":"Heliospheric X-ray Emission Associated with Charge Transfer of the Solar Wind with Interstellar Neutrals","volume":"532","author":"Cravens","year":"2000","journal-title":"Astrophys. J."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"24883","DOI":"10.1029\/2000JA000461","article-title":"Temporal variations of geocoronal and heliospheric X-ray emission associated with the solar wind interaction with neutrals","volume":"106","author":"Cravens","year":"2001","journal-title":"J. Geophys. Res."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1002\/2014JA020497","article-title":"X-ray imaging of Kelvin-Helmholtz waves at the magnetopause","volume":"120","author":"Sun","year":"2015","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"e28314","DOI":"10.1029\/2020JA028314","article-title":"Tangent directions of the cusp boundary derived from the simulated soft X-ray image","volume":"126","author":"Sun","year":"2021","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Hou, Q., Zhou, D., and Feng, J. (2021, January 21). Coordinate attention for efficient mobile network design. Proceedings of the IEEE\/CVF Conference on Computer Vision and Pattern Recognition, Nashville, TN, USA.","DOI":"10.1109\/CVPR46437.2021.01350"},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Zhang, Y., Sun, T., Carter, J.A., Liu, W., Sembay, S., Ji, L., and Wang, C. (2023). The Relationship between Solar Wind Charge Exchange Soft X-ray Emission and the Tangent Direction of Magnetopause in an XMM\u2013Newton Event. Magnetochemistry, 9.","DOI":"10.3390\/magnetochemistry9040088"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/11\/2771\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:42:48Z","timestamp":1760125368000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/11\/2771"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,5,26]]},"references-count":46,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2023,6]]}},"alternative-id":["rs15112771"],"URL":"https:\/\/doi.org\/10.3390\/rs15112771","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2023,5,26]]}}}