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Towards reinforcement learning in UAV relay for anti-jamming maritime communications

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Digital Communications and Networks 2023年第6期9卷 1477-1485页

作者： Chuhuan Liu Yi Zhang Guohang Niu luliang jia Liang Xiao jiangxia Luan Department of Information and Communication Engineering Xiamen UniversityXiamen361005China School of Space Information Space Engineering UniversityBeijing101400China Xiamen Meiya Pico Information Co. Ltd.Xiamen361005China

Maritime communications with sea surface reflections and sea wave occlusions are susceptible to jamming attacks due to the wide geographical area and intensive wireless communication *** Aerial Vehicles(UAVs)help relay messages to improve communication performance,but the relay policy that depends on the rapidly changing maritime environments is difficult to *** this paper,a reinforcement learning-based UAV relay policy for maritime communications is proposed to resist jamming *** on previous transmission performance,the relay location,the received power of the transmitted signal and the received jamming power,this scheme optimizes the UAV trajectory and relay power to save the energy consumption and decrease the Bit-Error-Rate(BER)of the maritime signals.A deep reinforcement learning-based scheme is also proposed,which designs a deep neural network with dueling architecture to further improve the communication performance and computational *** performance bounds regarding the signal to interference plus noise ratio,energy consumption and the communication utility are provided based on the Nash equilibrium of the game against jamming,and the computational complexity of the proposed schemes is *** results show that the proposed schemes improve the energy efficiency and decrease the BER compared with the benchmark.

关键词： Maritime communications Jamming Unmanned aerial vehicle Relay Reinforcement learning

Cooperative Anti-Jamming and Interference Mitigation for UAV Networks: A Local Altruistic Game Approach

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China Communications 2024年第2期21卷 183-196页

作者： Yueyue Su Nan Qi Zanqi Huang Rugui Yao luliang jia College of Electronic Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China School of Space Information Space Engineering UniversityBeijing 101416China

To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference and external malicious jamming. A cooperative anti-jamming and interference mitigation method based on local altruistic is proposed to optimize UAVs’ channel selection. Specifically, a Stackelberg game is modeled to formulate the confrontation relationship between UAVs and the jammer. A local altruistic game is modeled with each UAV considering the utilities of both itself and other UAVs. A distributed cooperative anti-jamming and interference mitigation algorithm is proposed to obtain the Stackelberg equilibrium. Finally, the convergence of the proposed algorithm and the impact of the transmission power on the system loss value are analyzed, and the anti-jamming performance of the proposed algorithm can be improved by around 64% compared with the existing algorithms.

关键词： channel selection cooperative antijamming and interference mitigation local altruistic game Stackelberg game unmanned aerial vehicle(UAV)

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多波束卫星通信功率分配算法与仿真分析

系统仿真学报 2014年第11期26卷 2687-2691页

作者：贾录良刘爱军郭道省王恒解放军理工大学通信工程学院南京210007

在多波束卫星通信系统中,星上的资源(功率和带宽等)是有限的。提高资源的利用率显得至关重要。针对现有的多波束卫星通信系统各个点波束下行功率分配采用固定的等功率分配方式与实际中不断变化的业务需求不相匹配,未能充分地利用有限的... 详细信息

在多波束卫星通信系统中,星上的资源(功率和带宽等)是有限的。提高资源的利用率显得至关重要。针对现有的多波束卫星通信系统各个点波束下行功率分配采用固定的等功率分配方式与实际中不断变化的业务需求不相匹配,未能充分地利用有限的功率资源。通过构建多波束卫星通信系统下行点波束容量模型,提出了一种基于业务需求的有效功率分配算法,利用拉格朗日对偶理论和次梯度法解决了该功率分配问题。仿真结果分析表明,该有效的功率分配算法可以获得灵活的系统可用容量,可以满足不同的业务需求,能够有效地利用有限的功率资源,提高了资源的利用率。

关键词：多波束卫星功率分配业务需求卫星通信

周期线性调频干扰信号分数阶频谱分析与参数估计方法

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计算机工程 2017年第12期43卷 108-114页

作者：周新姚富强牛英滔贾录良解放军理工大学通信工程学院南京210007 南京电讯技术研究所南京210007

针对跨周期的线性调频干扰信号的检测和参数估计问题,提出一种分数阶频谱分析与参数估计方法。以采样数据横跨2个周期为例,分析采样的周期线性调频干扰信号在分数阶傅里叶变换域的频谱分布特征,2个周期内的频谱重叠宽度与分数阶旋转角... 详细信息

针对跨周期的线性调频干扰信号的检测和参数估计问题,提出一种分数阶频谱分析与参数估计方法。以采样数据横跨2个周期为例,分析采样的周期线性调频干扰信号在分数阶傅里叶变换域的频谱分布特征,2个周期内的频谱重叠宽度与分数阶旋转角α和各周期内数据长度的关系,以及频谱尖峰发生偏移的条件。推导在离散分数阶傅里叶变换中各参数间的相互关系,得出采用快速解线性调频技术预估调频率的原因。实验结果表明,在2种仿真情况下,该方法都具有较高的参数估计精度。

关键词：周期线性调频信号抗干扰通信分数阶傅里叶变换频谱特征参数估计

基于博弈理论的认知星地网络抗干扰信道选择方法

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兵器装备工程学报 2023年第1期44卷 254-262页

作者：王梦阳贾录良颜培杰陈亚明航天工程大学航空信息学院北京100000 中国人民解放军66138部队北京100000 中国人民解放军31664部队青海格尔木816000

针对认知星地网络频谱稀缺、易受干扰的特点,研究了认知星地网络中的抗干扰信道选择问题。首先考虑到地面认知用户受到多方面干扰,根据用户和干扰之间的主从关系将其构造为Stackelberg博弈。同时针对用户间互扰呈现局部影响的特性,又将... 详细信息

针对认知星地网络频谱稀缺、易受干扰的特点,研究了认知星地网络中的抗干扰信道选择问题。首先考虑到地面认知用户受到多方面干扰,根据用户和干扰之间的主从关系将其构造为Stackelberg博弈。同时针对用户间互扰呈现局部影响的特性,又将用户间关系构造为图博弈,并从理论上证明上述博弈均衡的存在性。然后为了获得抗干扰信道选择问题的均衡解,提出一种基于局部信息交互的分层学习算法,在该算法中,认知用户不仅考虑自身吞吐量,还考虑邻居用户的吞吐量,通过局部最优实现全局最优。经过仿真分析,从实验层面验证了所提算法的收敛性和有效性。

关键词：认知星地网络抗干扰 Stackelberg博弈图博弈局部信息交互

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： jia Zhao Taixi Feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

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5G技术对军事领域的影响及思考

国防科技 2022年第1期43卷 21-25页

作者：庄春华贾录良朱毅中央军事委员会训练管理部北京100859 航天工程大学航天信息学院北京101416

5G通信技术将改变传统的通信方式。它致力于实现人与物、物与物的通信,实现万物互联,进而深刻改变人类社会。在军事领域,5G通信技术也将产生重大影响,加速军事领域的变革,深刻改变未来战场。本文首先阐述了5G通信技术高速率、低时延、... 详细信息

5G通信技术将改变传统的通信方式。它致力于实现人与物、物与物的通信,实现万物互联,进而深刻改变人类社会。在军事领域,5G通信技术也将产生重大影响,加速军事领域的变革,深刻改变未来战场。本文首先阐述了5G通信技术高速率、低时延、大容量等特点;其次,介绍了5G通信技术对军事领域的重大影响,如提升战场通信能力、推动战场武器平台的互联、推进智能化作战应用等;再次,梳理了5G军事应用需要解决的关键问题,对考虑战场环境机动性带来的大范围覆盖、关乎战场生存能力的通信抗干扰以及通信安全问题进行了深入分析,并给出了相应的解决思路;最后,阐述了迎接5G时代挑战的思考。

关键词： 5G 军事领域智能化

16.48% Efficient solution-processed CIGS solar cells with crystal growth and defects engineering enabled by Ag doping strategy

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Journal of Energy Chemistry 2025年第1期100卷 59-65页

作者： Mengyu Xu Shaocong Yan Ting Liang jia jia Shengjie Yuan Dongxing Kou Zhengji Zhou Wenhui Zhou Yafang Qi Yuena Meng Litao Han Sixin Wu Key Laboratory for Special Functional Materials of MOE National & Local Joint Engineering Research Centre for High-efficiency Display and Lighting Technology School of Nanoscience and Materials Engineering Henan University

Solution-processed Cu（In,Ga）Se2（CIGS） solar cells suffer from serious carrier recombination and power conversion efficiency（PCE） loss because of the poor film properties and easy formation of ***, we propose Ag&Se co-selenization strategy to enhance the crystallization and passivate harmful defects of the CIGS films. The formation of Ag-Se phase during the selenization process enables the formation of large grains and suppresses the deep level defects. It is found that Ag doping can enlarge the depletion region width, lower the Urbach energy and prolong the carrier lifetime. As a result, a champion solution-processed CIGS solar cell presents a high efficiency of 16.48% with the highly improved opencircuit voltage（VOC） of 662 m V and fill factor（FF） of 75.8%. This work provides an efficient strategy to prepare high quality solution-processed CIGS films for high-performance CIGS solar cells.

关键词： CIGS solar cells Solution-processed method Ag doping Crystal growth Defects engineering

Enhanced post-combustion CO2 capture and direct air capture by plasma surface functionalization of graphene adsorbent

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Journal of Energy Chemistry 2025年第1期100卷 653-664页

作者： Rahul Navik Eryu Wang Xiao Ding Huang Yunyi Yiyu Liu jia Li Guangdong-Hong Kong Joint Laboratory for Carbon Neutrality Jiangmen Laboratory of Carbon and Science and Technology Guangzhou HKUST Fok Ying Tung Research Institute The Hong Kong University of Science and Technology (Guangzhou) Carbon Neutrality and Climate Change Thrust Society Hub The Hong Kong University of Science and Technology (Guangzhou) Stoddart Institute of Molecular Science Department of Chemistry Zhejiang University

Graphene has enormous potential to capture CO2due to its unique properties and ***,graphene-based adsorbents have drawbacks of lower CO2adsorption capacity and poor *** work demonstrates a one-step rapid and sustainable N2/H2plasma treatment process to prepare graphene-based sorbent material with enhanced CO2adsorption *** treatment directly enriches amine species,increases surface area,and improves textural *** CO2adsorption capacity increases from 1.6 to 3.3 mmol/g for capturing flue gas,and from 0.14 to 1.3 mmol/g for direct air capture （DAC）.Importantly,the electrothermal property of the plasma-modified aerogels has been significantly improved,resulting in faster heating rates and significantly reducing energy consumption compared to conventional external heating for regeneration of *** aerogels display improved selectivity of 42 and 87 after plasma modification for 5 and 10 min,*** plasma-treated aerogels display minimal loss between 17%and 19% in capacity after 40 adsorption/desorption cycles,rendering excellent *** N2/H2plasma treatment of adsorbent materials would lower energy expenses and prevent negative effects on the global economy caused by climate change.

关键词： Carbon neutrality CO 2 capture Climate change Plasma treatment Graphene aerogel