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Journal of Systems Engineering and Electronics 2020年第5期31卷 884-889页

作者： wang wantian TANG Ziyue CHEN Yichang SUN Yongjian Department of Early Warning Technology Air Force Early Warning AcademyWuhan 430019China

This paper proposes a parity recognition of blade number and manoeuvre intention classification algorithm of rotor target based on the convolutional neural network(CNN) using micro Doppler features. Firstly, the time-frequency spectrograms are acquired from the radar echo by the short-time Fourier ***, based on the obtained spectrograms, a seven-layer CNN architecture is built to recognize the blade-number parity and classify the manoeuvre intention of the rotor target. The constructed architecture contains a leaky rectified linear unit and a dropout layer to accelerate the convergence of the architecture and avoid over-fitting. Finally, the spectrograms of the datasets are divided into three different ratios, i.e., 20%, 33% and 50%,and the cross validation is used to verify the effectiveness of the constructed CNN architecture. Simulation results show that, on the one hand, as the ratio of training data increases, the recognition accuracy of parity and manoeuvre intention is improved at the same signal-to-noise ratio(SNR);on the other hand, the proposed algorithm also has a strong robustness: the accuracy can still reach 90.72% with an SNR of – 6 dB.

关键词： micro-Doppler convolutional neural network(CNN) parity recognition of blade number manoeuvre intention classification

基于稀疏FrFT的窄带雷达目标架次识别方法

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系统工程与电子技术 2021年第8期43卷 2129-2136页

作者：陈一畅熊鑫王万田空军预警学院湖北武汉430019 抚远雷达站黑龙江佳木斯156500

架次识别对于窄带雷达编队目标的探测与识别具有重要意义。本文基于最小熵准则提出了稀疏分数阶傅里叶变换(fractional Fourier transform,FrFT)最优变换阶次估计算法,首先将雷达回波数据的FrFT结果的熵值建模为变换阶次的函数,进而将... 详细信息

架次识别对于窄带雷达编队目标的探测与识别具有重要意义。本文基于最小熵准则提出了稀疏分数阶傅里叶变换(fractional Fourier transform,FrFT)最优变换阶次估计算法,首先将雷达回波数据的FrFT结果的熵值建模为变换阶次的函数,进而将变换阶次估计问题转化为稀疏优化问题,利用稀疏重构算法获得最优变换阶次。最后,应用该算法分析窄带雷达多波门回波数据Doppler频率特性,获取编队目标的架次信息。仿真和实测数据结果表明,所提方法避免了暴力搜索能够快速获得FrFT最优变换阶次,将该算法应用于窄带雷达回波信号处理能够准确识别编队目标架次信息。

关键词：分数阶傅里叶变换最小熵稀疏优化窄带雷达架次识别

阵列自由度欠定条件下雷达干扰对消方法及性能分析

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系统工程与电子技术 2024年第11期46卷 3639-3647页

作者：张嘉毫李伟王万田王衡峰李亚星孟进海军工程大学军用电气科学与技术研究所电磁能技术全国重点实验室湖北武汉 430033

针对雷达、数据链等分时信息系统发射时隙产生的自干扰影响非合作干扰对消权值问题,分析辅助天线阵列自由度影响对消暂态权值收敛特性,提出非合作干扰对消权值保持方法.考虑辅助天线通道与主天线通道异构场景,定量推导非合作干扰对消输... 详细信息

针对雷达、数据链等分时信息系统发射时隙产生的自干扰影响非合作干扰对消权值问题,分析辅助天线阵列自由度影响对消暂态权值收敛特性,提出非合作干扰对消权值保持方法.考虑辅助天线通道与主天线通道异构场景,定量推导非合作干扰对消输出功率稳态性能边界与影响因素.结果表明,权值保持技术避免发射自干扰影响,增加辅助天线数量提升对消比和对消收敛特性.所提方法提升了阵列自由度欠定条件下非合作对消稳态和暂态性能,对于雷达非合作干扰对消设计具有现实指导意义.

关键词：非合作干扰干扰对消雷达抗干扰收发分时

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天空双基地预警雷达长时间相参积累算法研究

雷达科学与技术 2017年第4期15卷 397-402,409页

作者：王万田袁俊泉王力宝陈阿磊空军预警学院湖北武汉430019

天空双基地预警雷达体制中,信号传播距离远,回波信噪比低,且目标高速运动常导致回波越距离单元走动,从而影响目标检测性能。针对这一问题,将Keystone变换用于天空双基地预警雷达体制中,在建立空间几何模型的基础上,分析了回波越距离单... 详细信息

天空双基地预警雷达体制中,信号传播距离远,回波信噪比低,且目标高速运动常导致回波越距离单元走动,从而影响目标检测性能。针对这一问题,将Keystone变换用于天空双基地预警雷达体制中,在建立空间几何模型的基础上,分析了回波越距离单元走动特性,应用Keystone变换校正距离单元走动,并进行解多普勒模糊处理和基于单元选大准则的数据处理。该方法可以用于多个不同距离和速度的目标距离走动校正和相参积累检测。仿真结果验证了该方法具有良好的多目标检测性能。

关键词：天空双基地预警雷达 Keystone变换距离单元走动相参积累目标检测

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一种天基预警雷达目标运动参数估计方法

雷达科学与技术 2019年第4期17卷 461-466,472页

作者：周亮袁俊泉王万田郑岱堃空军预警学院

天基预警雷达系统中,由于卫星平台和目标间存在高速径向运动,回波信号会产生距离徙动和多普勒走动,导致FFT相参积累增益降低,不利于微弱目标检测。为了提高检测性能,需要准确估计出目标的运动参数,并对回波信号进行运动补偿。首先建立... 详细信息

天基预警雷达系统中,由于卫星平台和目标间存在高速径向运动,回波信号会产生距离徙动和多普勒走动,导致FFT相参积累增益降低,不利于微弱目标检测。为了提高检测性能,需要准确估计出目标的运动参数,并对回波信号进行运动补偿。首先建立了目标回波模型,分析了回波距离徙动和多普勒走动特性;其次利用Keystone变换校正回波距离徙动,并通过对多普勒模糊数的广义最大似然估计和MTD处理估计出目标的径向速度;然后对校正后的回波信号在方位向作延迟自相关处理,再利用FFT和Jacobson校正算法估计出目标的径向加速度;最后通过仿真实验验证了本文算法的有效性。

关键词：天基预警雷达运动参数估计 Keystone变换延迟自相关 Jacobsen校正算法

Dual modulation of homogeneous nanomaterialization and electrochemical activation enhancing zinc ion storage

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Science China Chemistry 2025年第1期68卷 385-393页

作者： Jianwei wang Huan wang Kangning wang Wenhui wang Wenlin Zhang Yanzhong Zhen School of Chemistry & Chemical Engineering Yan'an University

Vanadium-based electrode materials are widely investigated,but the low specific capacity and slow electrochemical kinetics in aqueous zinc-ion batteries still limit their commercial ***,the VS2/Ca V4O9material with the morphology of nanoflower was synthesized by a one-step hydrothermal *** to the blocky structure of pure VS2material,the VS2/Ca V4O9material is composed of thinner homogeneous *** open structures could provide abundant electrochemical active sites and ion transport channels,and then promote the electrochemical reaction *** addition,they can also buffer the bulk strain during the reaction *** improve the utilization of vanadium elements,an in-situ electrochemical activation strategy is used to explore the storage performance of the VS2/Ca V4O9material,the different activation voltage range of 0.4–1.6 and 0.4–1.4 V are selected,*** with the longer activation plateau of activated-VS2,the VS2/Ca V4O9cathode could quickly reach the activation state in the range of 1.4–1.6 V and cause the release of additional Zn storage sites *** VS2/Ca V4O9cathode delivers a higher power density of 37,000 W kg-1and a significant energy density of 423 Wh *** the high current density of 15 A g-1,the VS2/Ca V4O9cathode still has a discharge capacity of 183.9m Ah g-1after 5,000 cycles,and the capacity decay rate per cycle is only 0.0042%.Continuous cyclic voltammetry （CV） curves,electrochemical impedance spectroscopy （EIS） measurements,density functional theory （DFT） calculation and galvanostatic intermittent titration technique （GITT） measurements demonstrate that the VS2/Ca V4O9cathode has a faster ion diffusion/charge transfer ***,the assembled flexible device has an excellent mechanical stability.

关键词： dual modulation homogeneous nanomaterialization electrochemical activation zinc ion storage

一种天空双基地预警雷达高速机动目标检测算法

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空军预警学院学报 2017年第5期31卷 313-318页

作者：王万田袁俊泉王悦周亮空军预警学院武汉430019

针对天空双基地预警雷达高速机动目标的距离和多普勒徙动问题,提出了一种基于二次相位补偿的目标检测算法.该算法首先在距离频域内利用Keystone变换对脉压后目标回波信号进行距离徙动校正,然后根据径向加速度搜索值构造二次相位补偿函数... 详细信息

针对天空双基地预警雷达高速机动目标的距离和多普勒徙动问题,提出了一种基于二次相位补偿的目标检测算法.该算法首先在距离频域内利用Keystone变换对脉压后目标回波信号进行距离徙动校正,然后根据径向加速度搜索值构造二次相位补偿函数,对多普勒徙动进行补偿,遍历径向加速度搜索范围,获得的相参积累峰值的最大值所对应的径向加速度搜索值即为目标真实径向加速度的估计值,最后对补偿后的相参积累结果进行恒虚警处理.仿真结果表明,本文方法可有效校正距离徙动并补偿多普勒徙动,实现高速机动目标的相参积累,从而验证了所提算法的有效性.

关键词：天空双基地预警雷达目标检测 Keystone变换二次相位补偿

天空双基地预警雷达目标回波建模及徙动特性分析

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空军预警学院学报 2017年第4期31卷 235-242页

作者：王万田袁俊泉饶翚王悦空军预警学院武汉430019

为了开展天空双基地预警雷达目标检测技术研究,首先在建立空间几何模型的基础上,分析了目标运动特性、回波脉冲宽度及其对脉冲压缩性能的影响,进而建立了运动目标回波模型;然后研究了高速运动目标的距离徙动特性;最后对目标径向速度、... 详细信息

为了开展天空双基地预警雷达目标检测技术研究,首先在建立空间几何模型的基础上,分析了目标运动特性、回波脉冲宽度及其对脉冲压缩性能的影响,进而建立了运动目标回波模型;然后研究了高速运动目标的距离徙动特性;最后对目标径向速度、径向加速度与天基发射平台轨道倾角、初始轨道幅角、目标速度的变化关系以及距离徙动对相参积累性能的影响进行了仿真.仿真结果表明,天基发射平台高速运转、地球自转以及目标运动使得回波包络峰值跨距离徙动严重,积累能量分散在多个距离单元内,降低了目标的检测性能.

关键词：天空双基地预警雷达目标运动特性回波模型距离徙动相参积累

An Iterated Greedy Algorithm with Memory and Learning Mechanisms for the Distributed Permutation Flow Shop Scheduling Problem

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Computers, Materials & Continua 2025年第1期82卷 371-388页

作者： Binhui wang Hongfeng wang College of Information Science and Engineering Northeastern UniversityShenyang110819China

The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent *** iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because of its straightforward,single-solution evolution ***,a potential draw-back of IGA is the lack of utilization of historical information,which could lead to an imbalance between exploration and exploitation,especially in large-scale *** a consequence,this paper develops an IGA with memory and learning mechanisms(MLIGA)to efficiently solve the DPFSP targeted at the ***,we incorporate a memory mechanism to make a more informed selection of the initial solution at each stage of the search,by extending,reconstructing,and reinforcing the information from previous *** addition,we design a twolayer cooperative reinforcement learning approach to intelligently determine the key parameters of IGA and the operations of the memory ***,to ensure that the experience generated by each perturbation operator is fully learned and to reduce the prior parameters of MLIGA,a probability curve-based acceptance criterion is proposed by combining a cube root function with custom *** last,a discrete adaptive learning rate is employed to enhance the stability of the memory and *** ablation experiments are utilized to verify the effectiveness of the memory mechanism,and the results show that this mechanism is capable of improving the performance of IGA to a large ***,through comparative experiments involving MLIGA and five state-of-the-art algorithms on 720 benchmarks,we have discovered that MLI-GA demonstrates significant potential for solving large-scale *** indicates that MLIGA is well-suited for real-world distributed flow shop scheduling.

关键词： Distributed permutation flow shop scheduling makespan iterated greedy algorithm memory mechanism cooperative reinforcement learning

Controlled cationic ring-opening polymerization of L-lactide by organic ion pair: novel approach to isotactic-rich and crystalline polylactide

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Science China Chemistry 2025年第1期68卷 394-402页

作者： Zhiqiang Ding Mingqian wang Zijing Zhou Bin wang Yuesheng Li Tianjin Key Laboratory of Composite & Functional Materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of L-lactide is a promising approach to isotactic-rich and crystalline poly（L-lactide）.In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

关键词： organic ion pair controlled cationic ring-opening polymerization activated chain end mechanism isotactic-rich polylactide