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基于强化学习的多雷达抗干扰算法研究

现代雷达 2024年第2期46卷 131-137页

作者：智永锋邱璐莹张龙高红岗师浩博西北工业大学无人系统技术研究院陕西西安710072 西北工业大学民航学院陕西西安710072

针对多雷达系统在受到环境的扫频干扰下无法工作的问题,研究了基于深度强化学习的多雷达共存抗干扰算法。文中将环境划分为多个子频段,对干扰占用频段过程进行建模,用马尔可夫模型对多雷达系统进行建模;对双深度Q网络(Double DQN)强化... 详细信息

针对多雷达系统在受到环境的扫频干扰下无法工作的问题,研究了基于深度强化学习的多雷达共存抗干扰算法。文中将环境划分为多个子频段,对干扰占用频段过程进行建模,用马尔可夫模型对多雷达系统进行建模;对双深度Q网络(Double DQN)强化学习算法进行改进,与门控单元循环神经网络相结合,使之能处理依赖于长时间序列的干扰问题;提出了基于门控循环记忆的深度确定性策略强化学习算法,针对Double DQN强化学习中的网络臃肿和行动集合较大的问题进行了改进,采用直接输出行动策略,有效降低了网络复杂度。实验仿真结果表明,在多雷达存在的情况,该算法通过避开存在干扰的频点,不仅能够有效降低来自外界的干扰,还能减少己方雷达相互之间的干扰。

关键词：多雷达系统深度强化学习抗干扰马尔可夫模型门控循环单元

Adaptive IIR filtering based on balanced-realization

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Journal of Systems Engineering and Electronics 2013年第1期24卷 19-25页

作者： yongfeng zhi Panguo Fan Jun Zhang Department of Automatic Control Northwestern Polytechnical University

Due to low parameter sensitivity for balanced realiza- tions, balanced structure becomes a good candidate for an statespace adaptive infinite impluse response （IIR） filter. Here, using coefficients of the transfer function as the adaptive filtering parameters, a balanced adaptive IIR filtering algorithm is proposed for output-error minimization. The algorithm in the internally balanced realization guarantees that the adaptive IIR filter always minimizes the ratio of maximum-to-minimum eigenvalue of the Grammian matrices at the each iteration. Simulation results are provided to corroborate the proposed algorithm.

关键词： balanced realization adaptive infinite impluse response filtering state-space transformation.

Convergence and Performance Analysis of the Affine Projection Algorithm with Direction Error

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Chinese Journal of Electronics 2017年第2期26卷 351-357页

作者： zhi yongfeng SI Lei SHI Fuqian DAI Dameng School of Automation Northwestern Polytechnical University School of Information and Engineering Wenzhou Medical University College of Physics and Electronic Information Engineering Wenzhou University

A new statistical analysis model is proposed to analyze the Affine pro jection algorithm with direction error(AP-DE).Four assumptions are made,which are based on the direction vector for the AP-DE *** these assumptions,deterministic recursive equations for the weight error and for the mean-square error are *** also analyze the steady-state behavior of the AP-DE *** results are provided to corroborate the analytical results.

关键词： Adaptive filter Affine projection algorithm with direction error(AP-DE) Statistical analysis

Steady-state weights solution to affine projection algorithm

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控制理论与应用（英文版） 2012年第2期10卷 259-263页

作者： yongfeng zhi Jun Zhang Yinxue Li Department of Automatic Control Northwestern Polytechnical University Xi'an Shaanxi 710072 China

A new expression of the weights update equation for the affine projection algorithm （APA） is proposed that improves the convergence rate of an adaptive flter, particularly for highly colored input signals, and yields greater details of the internal structure. The steady-state weights solution to the APA algorithm is calculated in different step-sizes, which is significantly different from the iteration method. The weights error in steady-state is proved to be zero as the number of the input direction vector increases to infinity, ensuring that the estimated weights of the APA algorithm in steady-state are unbiased and consistent. The sensitivity of the step-size parameter for the steady-state weights is also analyzed. Simulation results show that the steady-state weights of the APA algorithm, obtained from the proposed method, are closer to the true weights than the estimated steady-state weights as determined by the traditional iteration method.

关键词： Affine projection algorithm Steady-state Identification Adaptive filtering

Diyne-linked and fully π-conjugated polymetalloporphyrin nanosheets for outstanding heterogeneous catalysis

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Science Bulletin 2021年第4期66卷 354-361,M0004页

作者： Kun Li Ziping Li yongfeng zhi Hong Xia Yuwei Zhang Xiaoming Liu College of Chemistry.Electron Microscopy Center Jilin UniversityChangchun 130012China Stare Key Laboratory on Integrated Optoelectronics College of Electronic Science and TechnologyJilin UniversityChangchun 130012China College of Chemistry Jilin Normal UniversityChangchun 130103China

Two-dimensional,ultrathin,robust,and fullyπ-conjugated organic nanomaterials are highly desirable for application in various fields due to their unique photoelectric characteristics and great number of exposed active ***,such matters combining excellent stability,fullπ-conjugation and adjustability are rare,which has become a bottleneck for their practical ***,we present a novel kind of diyne-linked polymetalloporphyrin nanosheet featuring permanent porosity and fullπ-conjugation,which exhibits a high-aspect-ratio,outstanding stability and convenient tailoring for electronic ***,the novel nanosheets with monodisperse nickel atoms were found to be outstanding heterogeneous catalyst with unprecedented catalytic activity and selectivity for 4-nitrophenol reduction to 4-aminophenol under mild *** findings recommend that diynelinked polymetalloporphyrin nanosheets may offer new platforms for the conversion of photoelectricity and energy in the future.

关键词： Covalent organic nanosheets Polymetalloporphyrin nanomaterials Heterogeneous catalysts Reduction reaction

ess Enhanced photothermoelectric conversion in selfrolled tellurium photodetector with geometryinduced energy localization

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Light(Science & Applications) 2024年第8期13卷 1545-1556页

作者： Jiayuan Huang Chunyu You Binmin Wu Yunqi Wang Ziyu Zhang Xinyu Zhang Chang Liu Ningge Huang zhi Zheng Tingqi Wu Suwit Kiravittaya yongfeng Mei Gaoshan Huang Department of Materials Science&State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai 200438China Yiwu Research Institute of Fudan University Yiwu 322000 ZhejiangChina International Institute of Intelligent Nanorobots and Nanosystems Fudan UniversityShanghai 200438China ShanghaiTech Quantum Device Lab ShanghaiTech UniversityShanghai 200120China Department of Electrical Engineering Faculty of EngineeringChulalongkorn UniversityBangkokThailand Shanghai Frontiers Science Research Base of Intelligent Optoelectronics and Perception Institute of OptoelectronicsFudan UniversityShanghai 200438China

Photodetection has attracted significant attention for information *** the implementation relies primarily on the photonic detectors,they are predominantly constrained by the intrinsic bandgap of active *** the other hand,photothermoelectric(PTE)detectors have garnered substantial research interest for their promising capabilities in broadband detection,owing to the self-driven photovoltages induced by the temperature *** get higher performances,it is crucial to localize light and heat energies for efficient ***,there is limited research on the energy conversion in PTE detectors at micro/nano *** this study,we have achieved a twoorder-of-magnitude enhancement in photovoltage responsivity in the self-rolled tubular tellurium(Te)photodetector with PTE *** illumination,the tubular device demonstrates a maximum photovoltage responsivity of 252.13 VW^(-1)and a large detectivity of 1.48×10^(11)*** disclose the mechanism of the PTE conversion in the tubular structure with the assistance of theoretical *** addition,the device exhibits excellent performances in wide-angle and polarization-dependent *** work presents an approach to remarkably improve the performance of photodetector by concentrating light and corresponding heat generated,and the proposed self-rolled devices thus hold remarkable promises for next-generation on-chip photodetection.

关键词： illumination energy primarily

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基于最大似然估计的一种新的信号处理方法

西北工业大学学报 2008年第2期26卷 179-183页

作者：智永锋张骏杨秉政赵娜西北工业大学自动化学院陕西西安710072

现代数字信号处理中的估计理论是一个重要的研究课题,为了在信号的估计中总能得到估计量,大量的估计都采用了最大似然估计,但是最大似然估计在处理含有随机噪声的信号时需要大量的观测数据。提出了一种基于最大似然估计的新的信号处理方... 详细信息

现代数字信号处理中的估计理论是一个重要的研究课题,为了在信号的估计中总能得到估计量,大量的估计都采用了最大似然估计,但是最大似然估计在处理含有随机噪声的信号时需要大量的观测数据。提出了一种基于最大似然估计的新的信号处理方法,采用最小二乘移位算法对信号进行分阶段滑动的计算,获得含有噪声的一簇数据,并对其进行最大似然估计,减少了需要观测数据的数据量和试验次数,并对估计结果的期望值、方差和误差在数据曲线上的分布进行了分析。仿真结果表明,该方法可以使估计信号渐进趋近于精确值,为信号消噪提供了有效的方法和途径。

关键词：最大似然估计最小二乘概率密度函数

基于DSP的车载智能移动报警监控系统设计与实现

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西北工业大学学报 2013年第2期31卷 189-194页

作者：乔鸿海薛静徐继伟智永锋西北工业大学自动化学院陕西西安710072

针对车载智能监控的要求,设计一种嵌入式车体移动报警安全监控系统。系统以TMS320DM642芯片为核心,采用简化的Itti模型来提取监控画面的颜色和亮度特征,并检测和分割出感兴趣区域(Regions of Interest)。根据ROI质心相似度的变化来判断... 详细信息

针对车载智能监控的要求,设计一种嵌入式车体移动报警安全监控系统。系统以TMS320DM642芯片为核心,采用简化的Itti模型来提取监控画面的颜色和亮度特征,并检测和分割出感兴趣区域(Regions of Interest)。根据ROI质心相似度的变化来判断车辆状态。实验结果表明:该系统较为准确地检测和分割感兴趣区域,并能对其进行实时地监控;系统对车辆状态的判断和报警可靠性较高。

关键词：车辆安全监控数字信号处理器感兴趣区域检测 Itti视觉显著模型相似度

基于改进SURF算法的交通视频车辆检索方法研究

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西北工业大学学报 2014年第2期32卷 297-302页

作者：张子龙薛静乔鸿海智永锋西北工业大学自动化学院陕西西安710072

针对传统车辆检索方法中存在准确性和区分度较低的问题,提出了一个基于改进SURF(speeded up robust features)算法的视频车辆检索方法。在车辆视频关键帧提取的基础上,根据改进SURF算法完成车辆图像的特征提取及匹配,其中包含改进FAST(f... 详细信息

针对传统车辆检索方法中存在准确性和区分度较低的问题,提出了一个基于改进SURF(speeded up robust features)算法的视频车辆检索方法。在车辆视频关键帧提取的基础上,根据改进SURF算法完成车辆图像的特征提取及匹配,其中包含改进FAST(features from accelerated segment test)特征点检测、SURF特征向量提取以及最近邻查询方法来进行特征点的匹配;通过计算比较待检索车辆图像与数据库车辆图像的相似度,算法完成图像筛选并反馈检索结果。实验结果表明:针对交通监控视频中待检索车辆,该方法能够较为准确地进行检索并反馈结果。

关键词：车辆视频检索改进SURF算法改进FAST特征点特征点匹配相似度