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Chinese Physics B 2022年第2期31卷 581-586页

作者： Xinlin Mi ledong wang Qi Zhang Yitong Sun Yufeng Tian Shishen Yan Lihui Bai School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China

We theoretically and experimentally studied the Gilbert damping evolution of both acoustic and optical magnetic resonance modes in the layered flake Cr Cl;with an external magnetic field H applied in *** on a Lagrangian equation and a Rayleigh dissipation function,we predicted that the resonance linewidth△H as a function of microwave frequencyωis nonlinear for both acoustic and optical modes in the Cr Cl;flake,which is significantly different from the linear relationship of△H-ωin *** the microwave transmission through the Cr Cl;flake,we obtained theω–H dispersion and damping evolution△H–ωfor both acoustic and optical *** both our theoretical prediction and experimental observations,we concluded that the nonlinear damping evolution△H–ωis a consequence of the interlayer interaction during the antiferromagnetic resonance,and the interlayer Gilbert dissipation plays an important role in the nonlinear damping evolution because of the asymmetry of the non-collinear magnetizaiton between layers.

关键词： Gilbert damping antiferromagnetic resonance(AFMR) CrCl_(3)

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蒸发波导激光雷达的原理与信号接收系统设计

红外与激光工程 2012年第11期41卷 2945-2951页

作者：王乐东王江安张峰海军工程大学电子工程学院湖北武汉430033

从海洋大气相对湿度的角度出发建立了大气折射率变化与气溶胶激光散射特性的理论联系，着重对蒸发波导激光雷达的信号接收系统进行了设计。针对微弱光信号接收、光电转换与电压放大的难点，前端信号调理电路采用雪崩光电二极管和宽带低... 详细信息

从海洋大气相对湿度的角度出发建立了大气折射率变化与气溶胶激光散射特性的理论联系，着重对蒸发波导激光雷达的信号接收系统进行了设计。针对微弱光信号接收、光电转换与电压放大的难点，前端信号调理电路采用雪崩光电二极管和宽带低噪声放大器对所述高速瞬态微弱光信号进行接收和二级放大，同时保证了系统的高增益、宽宽带及低噪声性能。采用波长为1．064μm的激光雷达对半径范围为0．1-20μm的气溶胶粒子群进行探测实验，进一步验证了信号接收系统的分辨率和灵敏度。

关键词：激光雷达蒸发波导雪崩光电二极管气溶胶放大器

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相邻帧间匹配的迎头点目标跟踪算法

光学学报 2009年第11期29卷 3004-3009页

作者：王乐东王江安康圣宗思光周润芝海军工程大学光电对抗与光通信研究所湖北武汉430033

针对海空复杂背景下迎头点目标检测与跟踪难题,提出了一种基于相邻帧间匹配的边检测边跟踪算法。算法对相邻红外图像序列帧间点与点的邻域匹配,标记匹配结果兴趣区域像素点,统计标记次数,与输入单帧图像同步显示迎头目标检测结果。算法... 详细信息

针对海空复杂背景下迎头点目标检测与跟踪难题,提出了一种基于相邻帧间匹配的边检测边跟踪算法。算法对相邻红外图像序列帧间点与点的邻域匹配,标记匹配结果兴趣区域像素点,统计标记次数,与输入单帧图像同步显示迎头目标检测结果。算法主要特点在于无需提前假定疑似目标点位置,单个匹配过程与当前相邻两帧外的其它序列帧无关,整个匹配过程不随目标数目多少或运动状态变化而改变。根据仿真和实拍照片实验,证实了理论上区别于传统算法的上述优点,在军事应用中具有较高的参考价值。

关键词：图像处理目标跟踪匹配点目标红外图像阈值

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迎头目标的红外图像特征与检测难点分析

计算机与数字工程 2011年第3期39卷 148-150页

作者：谢辉王乐东海军驻河南科技大学后备军官选拔培训办公室洛阳471003 海军工程大学电子工程学院武汉430033

有关迎头目标的理论分析对海战场上攻击和预警双方都有着极高研究价值。文章在介绍具有最强攻击力的迎头目标的军事价值基础上,分析了迎头目标的物理运动特点和红外成像特征,总结了对其有效检测的几个难点及原因,得出了对红外图像中迎... 详细信息

有关迎头目标的理论分析对海战场上攻击和预警双方都有着极高研究价值。文章在介绍具有最强攻击力的迎头目标的军事价值基础上,分析了迎头目标的物理运动特点和红外成像特征,总结了对其有效检测的几个难点及原因,得出了对红外图像中迎头目标单帧检测和多帧跟踪的研究重点,为研究在复杂环境下对迎头目标的检测与跟踪算法提供参考。

关键词：图像处理红外图像迎头目标目标检测

Swarm intention identification via dynamic distribution probability image

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Chinese Journal of Aeronautics 2024年第10期37卷 380-392页

作者： Yinhan wang Jiang wang Shaoming HE Fei wang Qi wang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

In the realm of decision-making for defense and security applications,it is paramount to swiftly and accurately identify the intentions of incoming *** identification methods predominantly focus on single-target applications and overlook the perturbations introduced by measurement *** this study,we propose a novel concept:the Dynamic Distribution Probability(DDP)image,which is constructed using the estimated state and its covariance *** grayscale pixel value within the image signifies the probability of the presence of the agent within the *** proposed identification scheme integrates the use of Extended Kalman Filter(EKF),Convolutional Neural Network(CNN),Back Propagation(BP)network,and Gated Recurrent Unit(GRU)***,the DDP image is processed through a CNN to distill the formation characteristics,and the estimated swarm state from EKF is inputted into a BP network to deduce the kinematic *** outputs from both networks are summed and subsequently channeled into a GRU network to capture temporal *** numerical simulations and flight experiments are presented to demonstrate the robust anti-noise capability of the proposed scheme compared with conventional methods,as well as its superior training efficiency.

关键词： Intention Identification Kalman filters Convolutional neural networks Swarm intelligence

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

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网络空间恶意信息传播的主动对抗机理与应用

网络空间安全 2020年第7期11卷 92-96页

作者：王乐东田楠叶忠中国人民解放军91977部队北京100841

针对网络空间恶意信息传播的管控问题,分析了恶意信息的传播主体、传播行为、传播路径的技术特征,基于可信计算主动免疫管控技术,运用主体认证授权、行为可信控制、路径策略配置等机制,构建了恶意信息传播主动对抗框架模型,并结合不同... 详细信息

针对网络空间恶意信息传播的管控问题,分析了恶意信息的传播主体、传播行为、传播路径的技术特征,基于可信计算主动免疫管控技术,运用主体认证授权、行为可信控制、路径策略配置等机制,构建了恶意信息传播主动对抗框架模型,并结合不同等级网络的管控目标,设计了恶意信息区域化对抗管控应用模型,能够为恶意信息网络阻断、隔离、控制等网络空间治理提供对策支撑。

关键词：可信计算网络安全恶意信息主动对抗

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： wang Yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality