Preparation and Properties of Atomic-Oxygen Resistant Polyimide Films Based on Multi-Ring Fluoro-Containing Dianhydride and Phosphorus-Containing Diamine by Zhenzhong Wang, Xi Ren, Yan Zhang, Changxu Yang, Shujun Han, Yuexin Qi, Jingang Liu

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Weather-Conscious Adaptive Modulation and Coding Scheme for Satellite-Related Ubiquitous Networking and Computing by Shiqi Zhang, Guoxin Yu, Shanping Yu, Yanjun Zhang, Yan Zhang

“…As a crucial part of ubiquitous networking and computing (UNC) technologies, low earth orbit (LEO) satellite communications aim at providing internet connectivity services everywhere. …”
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Security Performance Analysis of LEO Satellite Constellation Networks under DDoS Attack by Yan Zhang, Yong Wang, Yihua Hu, Zhi Lin, Yadi Zhai, Lei Wang, Qingsong Zhao, Kang Wen, Linshuang Kang

“…Low Earth orbit satellite constellation networks (LSCNs) have attracted significant attention around the world due to their great advantages of low latency and wide coverage, but they also bring new challenges to network security. …”
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Preparation and Characterization of Transparent Polyimide Nanocomposite Films with Potential Applications as Spacecraft Antenna Substrates with Low Dielectric Features and Good Sus... by Yan Zhang, Bo-han Wu, Han-li Wang, Hao Wu, Yuan-cheng An, Xin-xin Zhi, Jin-gang Liu

“…Optically transparent polyimide (PI) films with good dielectric properties and long-term sustainability in atomic-oxygen (AO) environments have been highly desired as antenna substrates in low earth orbit (LEO) aerospace applications. However, PI substrates with low dielectric constant (low-<i>D</i>_k), low dielectric dissipation factor (low-<i>D</i>_f) and high AO resistance have rarely been reported due to the difficulties in achieving both high AO survivability and good dielectric parameters simultaneously. …”
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Atomic Oxygen-Resistant Polyimide Composite Films Containing Nanocaged Polyhedral Oligomeric Silsesquioxane Components in Matrix and Fillers by Yan Zhang, Hao Wu, Yi-dan Guo, Yan-bin Yang, Qiang Yu, Jin-gang Liu, Bo-han Wu, Feng-zhu Lv

“…For the development of spacecraft with long-servicing life in low earth orbit (LEO), high-temperature resistant polymer films with long-term atomic oxygen (AO) resistant features are highly desired. …”
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Preparation and Properties of Intrinsically Atomic-Oxygen Resistant Polyimide Films Containing Polyhedral Oligomeric Silsesquioxane (POSS) in the Side Chains by Hao Wu, Yan Zhang, Yi-Dan Guo, Hao-Ran Qi, Yuan-Cheng An, Yan-Jiang Jia, Yao-Yao Tan, Jin-Gang Liu, Bo-Han Wu

“…The relatively poor atomic-oxygen (AO) resistance of the standard polyimide (PI) films greatly limits the wide applications in low earth orbit (LEO) environments. The introduction of polyhedral oligomeric silsesquioxane (POSS) units into the molecular structures of the PI films has been proven to be an effective procedure for enhancing the AO resistance of the PI films. …”
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An Empirical Atmospheric Density Calibration Model Based on Long Short-Term Memory Neural Network by Yan Zhang, Jinjiang Yu, Junyu Chen, Jizhang Sang

“…The accuracy of the atmospheric mass density is one of the most important factors affecting the orbital precision of spacecraft at low Earth orbits (LEO). Although there are a number of empirical density models available to use in the orbit determination and prediction of LEO spacecraft, all of them suffer from errors of various degrees. …”
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