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china Communications 2024年第6期21卷 53-68页

作者： zhang Zhenyu zhang Yong Yuan Siyu Cheng Zhenjie school of electronic engineering Beijing University of Posts and TelecommunicationsBeijing 100876China beijing Key laboratory of Work Safety Intelligent Monitoring(beijing university of posts and telecommunications) Beijing 100876China

In this paper,we propose the Two-way Deep Reinforcement learning(DRl)-Based resource allocation algorithm,which solves the problem of resource allocation in the cognitive downlink network based on the underlay *** users(SUs)in the cognitive network are multiplexed by a new Power Domain Sparse Code Multiple Access(PD-SCMA)scheme,and the physical resources of the cognitive base station are virtualized into two types of slices:enhanced mobile broadband(eMBB)slice and ultrareliable low latency communication(URllC)*** design the Double Deep Q Network(DDQN)network output the optimal codebook assignment scheme and simultaneously use the Deep Deterministic Policy Gradient(DDPG)network output the optimal power allocation *** objective is to jointly optimize the spectral efficiency of the system and the Quality of Service(QoS)of *** results show that the proposed algorithm outperforms the CNDDQN algorithm and modified JEERA algorithm in terms of spectral efficiency and QoS ***,compared with the Power Domain Non-orthogonal Multiple Access(PD-NOMA)slices and the Sparse Code Multiple Access(SCMA)slices,the PD-SCMA slices can dramatically enhance spectral efficiency and increase the number of accessible users.

关键词： cognitive radio deep reinforcement learning network slicing power-domain non-orthogonal multiple access resource allocation

Remote sensing and its applications using GNSS reflected signals:advances and prospects

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Satellite Navigation 2024年第1期5卷 10-51页

作者： Shuanggen Jin Adriano Camps Yan Jia Feng Wang Manuel Martin-Neira Feixiong huang Qingyun Yan Shuangcheng zhang Zhongyu li Komi Edokossi Dongkai yang Zhiyu Xiao Zhongmin Ma Weihua Bai Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai200030China school of Surveying and land Information engineering Henan Polytechnic UniversityJiaozuo454003China Department of Signal Theory and Communications Technical University of CataloniaBarcelona08034Spain Department of Surveying and Geoinformatics Nanjing University of Posts and TelecommunicationsNanjing210023China school of electronics and Information engineering Beihang UniversityBeijing100191China European Space Research and Technology Centre(ESTEC) European Space Agency2200-AGNoordwijkThe Netherlands National Space Science Center Chinese Academy of SciencesBeijing100190China school of Remote Sensing and Geomatics engineering Nanjing University of Information Science and TechnologyNanjing210044China College of Geological engineering and Geomatics Chang’an UniversityXi’an710054China university of electronic Science and Technology of china Chengdu611731China

The Global Navigation Satellite Systems(GNSS),including the US’s GPS,china’s BDS,the European Union’s Galileo,and Russia’s GlONASS,offer real-time,all-weather,any-time,anywhere and high precision observations by transmitting l band signals continuously,which have been widely used for positioning,navigation and *** the development of GNSS technology,it has been found that GNSS-reflected signals can be used to detect Earth’s surface characteristics together with other signals of *** this paper,the current status and latest advances are presented on Global Navigation Satellite System-Reflectometry(GNSS-R)in theory,methods,techniques and *** developments and progresses in GNSS-R instruments,theoretical modeling,and signal processing,ground and space-/air-borne experiments,parameters retrieval(*** speed,sea surface height,soil moisture,ice thickness),sea surface altimetry and applications in the atmosphere,oceans,land,vegetation,and cryosphere are given and reviewed in ***,the challenges in the GNSS-R development of each field are also ***,the future applications and prospects of GNSS-R are discussed,including multi-GNSS reflectometry,new GNSS-R receivers,GNSS-R missions,and emerging applications,such as mesoscale ocean eddies,ocean phytoplankton blooms,microplastics detection,target recognition,river flow,desert studies,natural hazards and landslides monitoring.

关键词： GNSS Reflectometry Remote sensing Environmental change

Assembling molybdenum-doped platinum clusters into a coral-like nanostructure for highly enhanced oxygen reduction

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eScience 2024年第1期4卷 123-131页

作者： linwei Zheng Mang Niu Tiantian Zeng Xiaohang Ge Yanrui Wang Chun Xian Guo Weiyong Yuan Dapeng Cao lian ying zhang Chang Ming li Institute of Materials for Energy and Environment Institute of Biochemical EngineeringCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China Institute for Materials Science and Devices School of Materials Science and EngineeringSuzhou University of Science and TechnologySuzhou 215011PR China Ningbo Research Institute Zhejiang UniversityNingbo 315100China State Key laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

Regulating the electronic and geometric structures of electrocatalysts is an effective strategy to boost their catalytic ***,a coral-like nanostructure is assembled with Mo-doped Pt clusters to form a highly active catalyst toward the oxygen reduction reaction(ORR).The advantages of a Mo-doped porous skeleton,grain boundaries,and MoOx species on the Pt cluster surfaces synergistically boost the electrocatalytic *** unique architecture delivers 3.5-and 2.8-fold higher mass and specific activities,respectively,than commercial Pt/*** functional theory calculations reveal that the Mo-doped Pt clusters have an optimized Pt–O bond length of 2.110Å,which weakens the adsorption energy of the intermediate O*to yield great ORR ***,the catalyst shows a decay in the half-wave potential of only 8 mV after 10,000 cycles of accelerated durability *** high stability arises from the increased dissociation energy of Pt atoms and the stable architecture of the coral-like structure of clusters.

关键词： Pt clusters Mo doping Porous structure Pt-O bond Oxygen reduction reaction

A Study on the EM leakage Arising from Braided Shielding Cable

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The Journal of china Universities of posts and telecommunications 2005年第3期12卷 67-70页

作者： zhang hong-xin lü ying-hua BAO Yong-fang lü Jian-gang school of Electric engineering Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

To investigate the electromagnetic leakage caused by braided shidding cable, the finite-difference formulation of braided shielding cable for both the inner shield-conductor circuit and outer shield-ground circuit are proposed. Then, the current in shield-ground circuit induced by the transmitting signal in the cable is computed in time-domain, and the shielding effectiveness of braided shield against trapezoid signals is studied. Further more, the video EM leakage in far zone is calculated. At last, the information leakage caused by EM radiation of braided cable is intercepted and recovered using the simulation platform. It is proved that EM radiation of braided cable can give rise to information leakage. It is a key factor that should be concerned in the information secure field.

关键词： braided shielding cable electromagnetic radiation information leakage information secure

Understanding synergistic catalysis on Pt–Cu diatomic sites via operando X-ray absorption spectroscopy in sulfur redox reactions

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eScience 2024年第5期4卷 110-119页

作者： Shuai Xie xingjia Chen leilei Wang Guikai zhang Haifeng lv Guolei Cai ying-Rui lu Ting-Shan Chan e Jing zhang Juncai Dong hongchang Jin Xianghua Kong Junling lu Song Jin Xiaojun Wu Hengxing Ji Hefei National laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China school of Chemistry and Material Sciences CAS Key Laboratory of Materials for Energy Conversionand CAS Center for Excellence in Nanoscience and Synergetic Innovation of Quantum Information and Quantum TechnologyUniversity of Science and Technology of ChinaHefei 230026China Hefei National laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsSchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China beijing Synchrotron Radiation laboratory Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China National Synchrotron Radiation Research Center Hsinchu 300092China school of Chemistry and Chemical engineering Hefei University of TechnologyHefei 230009China

Sulfur redox reactions render lithium–sulfur(li–S)batteries with an energy density of>500Whkg−1 but suffer a low practical capacity and fast capacity fade due to sluggish sulfur redox reaction(SRR)kinetics,which lies in the complex reaction process that involves a series of reaction intermediates and proceeds via a cascade ***,we present a Pt–Cu dual-atom catalyst(Pt/Cu-NG)as an electrocatalyst for sulfur redox ***/Cu-NG enabled the rapid conversion of soluble polysulfide intermediates into insoluble li2S2/li2S,and consequently,it prevented the accumulation and shuttling of lithium polysulfides,thus outperforming the corresponding single-atom catalysts(SACs)with individual Pt or Cu *** X-ray absorption spectroscopy and density functional theory calculations revealed that a synergistic effect between the paired Pt and Cu atoms modifies the electronic structure of the Pt site through d-orbital interactions,resulting in an optimal moderate interaction of the metal atom with the different sulfide *** optimal interaction enhanced charge transfer kinetics and promoted sulfur redox *** work thus provides important insights on the atomic scale into the synergistic effects operative in dual-atom catalysts and will thus pave the way to electrocatalysts with enhanced efficiency for high-performance li–S batteries.

关键词： Dual-atom catalysts Sulfur redox reaction lithium-sulfur batteries Synergistic interaction X-ray absorption spectroscopy

饱和吸收体恢复时间对正交偏振耗散孤子的影响

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中国光学（中英文） 2024年第3期17卷 714-723页

作者：何晓颖张川张银东饶岚北京邮电大学电子工程学院天地互联与融合北京市重点实验室北京100876

偏振在脉冲锁模时,对其塑形和稳定起着至关重要的作用。本研究开发了一种用于产生正交偏振耗散孤子的被动锁模石墨烯光纤激光器的正交偏振数值模拟。重点是分析由偏振依赖的石墨烯微光纤饱和吸收体引起的净正常色散双折射腔对正交偏振... 详细信息

偏振在脉冲锁模时,对其塑形和稳定起着至关重要的作用。本研究开发了一种用于产生正交偏振耗散孤子的被动锁模石墨烯光纤激光器的正交偏振数值模拟。重点是分析由偏振依赖的石墨烯微光纤饱和吸收体引起的净正常色散双折射腔对正交偏振孤子的影响。研究结果表明,这种饱和吸收体的恢复时间显著影响正交偏振耗散脉冲的特性,如能量、脉宽、时间带宽乘积和啁啾。结果显示,其恢复时间为120飞秒时最佳,产生两个具有大啁啾的正交偏振的窄耗散孤子脉冲,分别约为7.47 ps和8.06 ps。这对于开发紧凑、高功率、偏振耗散孤子光纤激光系统具有重要意义。

关键词：正交偏振光被动锁模净正常色散腔恢复时间

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紫外光非直视通信研究进展

光通信研究 2024年第2期2期(17)卷 121-130页

作者：张颖王沸钢何华宋鹏柯熙政西安理工大学自动化与信息工程学院西安710048 西安邮电大学通信与信息工程学院西安710061 西安工程大学电子信息学院西安710600

紫外光技术在军事和民用领域有着广泛的应用,如空间探测、紫外光制导、紫外干扰、电晕放电检测和军事通信等领域。文章从紫外光的单次和多次散射出发,介绍了紫外光通信的国内外进展,分析了紫外光通信中的不同链路情况,针对非直视链路紫... 详细信息

紫外光技术在军事和民用领域有着广泛的应用,如空间探测、紫外光制导、紫外干扰、电晕放电检测和军事通信等领域。文章从紫外光的单次和多次散射出发,介绍了紫外光通信的国内外进展,分析了紫外光通信中的不同链路情况,针对非直视链路紫外通信的脉冲展宽效应和大气湍流影响进行了探讨,总结了紫外光Ad Hoc网络,最后对紫外光通信的发展进行了展望。

关键词： Ad Hoc网络信道建模脉冲展宽紫外光通信

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基于改进深度Q网络的虚拟电厂实时优化调度

中国电力 2024年第1期57卷 91-100页

作者：张超赵冬梅季宇张颖华北电力大学电气与电子工程学院北京102206 国网上海能源互联网研究院有限公司上海200120

深度强化学习算法以数据为驱动,且不依赖具体模型,能有效应对虚拟电厂运营中的复杂性问题。然而,现有算法难以严格执行操作约束,在实际系统中的应用受到限制。为了克服这一问题,提出了一种基于深度强化学习的改进深度Q网络(improved dee... 详细信息

深度强化学习算法以数据为驱动,且不依赖具体模型,能有效应对虚拟电厂运营中的复杂性问题。然而,现有算法难以严格执行操作约束,在实际系统中的应用受到限制。为了克服这一问题,提出了一种基于深度强化学习的改进深度Q网络(improved deep Q-network,MDQN)算法。该算法将深度神经网络表达为混合整数规划公式,以确保在动作空间内严格执行所有操作约束,从而保证了所制定的调度在实际运行中的可行性。此外,还进行了敏感性分析,以灵活地调整超参数,为算法的优化提供了更大的灵活性。最后,通过对比实验验证了MDQN算法的优越性能。该算法为应对虚拟电厂运营中的复杂性问题提供了一种有效的解决方案。

关键词：虚拟电厂实时优化深度强化学习云边协同优化调度

Recent advances in artificial intelligence generated content

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Frontiers of Information Technology & electronic engineering 2024年第1期25卷 1-5页

作者： Junping zhang lingyun SUN Cong JIN Junbin GAO Xiaobing lI Jiebo lUO Zhigeng PAN ying TANG Jingdong WANG school of Computer Science Fudan UniversityShanghai 200433China International Design Institute Zhejiang UniversityHangzhou 310058China school of Information and Communication engineering Communication University of ChinaBeijing 100024China The university of Sydney Business school The University of SydneyNSW 2006Australia Department of AI Music and Music Information Technology Central Conservatory of MusicBeijing 100032China Department of Computer Science University of RochesterNY 14627USA school of Artificial Intelligence Nanjing University of Information Science and TechnologyNanjing 210044China Electrical and Computer engineering Department Rowan UniversityGlassboroNJ 08028USA Baidu Beijing 100085China

Artificial intelligence generated content(AIGC)has been a research hotspot in the field of artificial intelligence in recent *** is expected to replace humans in performing some of the work of content generation at a low cost and a high volume,such as music,painting,multimodal content generation,news articles,summary reports,stock commentary summaries,and even content and digital people generated in the *** provides a new technical path for the development and implementation of AI in the future.

关键词： artificial replace content