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Random walk dispersion model for missile contrail particles in cross-airspace environments
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作者 Chenshuo Li Debin Fu Tianyu Wei 《Defence Technology(防务技术)》 2025年第7期307-320,共14页
Missiles provide long-range precision strike capabilities and have become a cornerstone of modern warfare.The contrail clouds formed by missile during their active flight phase present significant chal-lenges to high-... Missiles provide long-range precision strike capabilities and have become a cornerstone of modern warfare.The contrail clouds formed by missile during their active flight phase present significant chal-lenges to high-altitude environmental observation and target detection and tracking.Existing studies primarily focus on specific airspace regions,leaving critical gaps in understanding the effects of long dispersion times,wide altitude ranges,and variable atmospheric conditions on missile contrail clouds.To address these gaps,this article develops a numerical method based on the Lagrangian random walk model,which incorporates various velocity variation terms,including particle velocity caused by the difference of wind field,by the thermal motion of local gas molecules and by random collisions between contrail cloud particles to capture the influence of environmental wind fields,atmospheric conditions,and particle concentrations on the motion of contrail cloud particles.A general coordinate system aligned with the missile's flight trajectory is employed to represent particle distribution characteristics.The proposed method is in good agreement with the conducted experiments as well as with the available numerical simulations.The results demonstrate that the proposed model effectively simulates the dispersion state of contrail clouds,accurately reflecting the impact of large-scale wind field variations and altitude changes with high computational efficiency.Additionally,simulation results indicate that the increased distance between gas molecules in rarefied environments facilitates enhanced particle dispersion,while larger particles exhibit a faster dispersion rate due to their greater mass. 展开更多
关键词 missile contrail Dispersion process Random walk model Concentration distribution Cross-airspace
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Multi-platform collaborative MRC-PSO algorithm for anti-ship missile path planning
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作者 LIU Gang GUO Xinyuan +2 位作者 HUANG Dong CHEN Kezhong LI Wu 《Journal of Systems Engineering and Electronics》 2025年第2期494-509,共16页
To solve the problem of multi-platform collaborative use in anti-ship missile (ASM) path planning, this paper pro-posed multi-operator real-time constraints particle swarm opti-mization (MRC-PSO) algorithm. MRC-PSO al... To solve the problem of multi-platform collaborative use in anti-ship missile (ASM) path planning, this paper pro-posed multi-operator real-time constraints particle swarm opti-mization (MRC-PSO) algorithm. MRC-PSO algorithm utilizes a semi-rasterization environment modeling technique and inte-grates the geometric gradient law of ASMs which distinguishes itself from other collaborative path planning algorithms by fully considering the coupling between collaborative paths. Then, MRC-PSO algorithm conducts chunked stepwise recursive evo-lution of particles while incorporating circumvent, coordination, and smoothing operators which facilitates local selection opti-mization of paths, gradually reducing algorithmic space, accele-rating convergence, and enhances path cooperativity. Simula-tion experiments comparing the MRC-PSO algorithm with the PSO algorithm, genetic algorithm and operational area cluster real-time restriction (OACRR)-PSO algorithm, which demon-strate that the MRC-PSO algorithm has a faster convergence speed, and the average number of iterations is reduced by approximately 75%. It also proves that it is equally effective in resolving complex scenarios involving multiple obstacles. More-over it effectively addresses the problem of path crossing and can better satisfy the requirements of multi-platform collabora-tive path planning. The experiments are conducted in three col-laborative operation modes, namely, three-to-two, three-to-three, and four-to-two, and the outcomes demonstrate that the algorithm possesses strong universality. 展开更多
关键词 anti-ship missiles multi-platform collaborative path planning particle swarm optimization(PSO)algorithm
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Trajectory prediction algorithm of ballistic missile driven by data and knowledge
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作者 Hongyan Zang Changsheng Gao +1 位作者 Yudong Hu Wuxing Jing 《Defence Technology(防务技术)》 2025年第6期187-203,共17页
Recently, high-precision trajectory prediction of ballistic missiles in the boost phase has become a research hotspot. This paper proposes a trajectory prediction algorithm driven by data and knowledge(DKTP) to solve ... Recently, high-precision trajectory prediction of ballistic missiles in the boost phase has become a research hotspot. This paper proposes a trajectory prediction algorithm driven by data and knowledge(DKTP) to solve this problem. Firstly, the complex dynamics characteristics of ballistic missile in the boost phase are analyzed in detail. Secondly, combining the missile dynamics model with the target gravity turning model, a knowledge-driven target three-dimensional turning(T3) model is derived. Then, the BP neural network is used to train the boost phase trajectory database in typical scenarios to obtain a datadriven state parameter mapping(SPM) model. On this basis, an online trajectory prediction framework driven by data and knowledge is established. Based on the SPM model, the three-dimensional turning coefficients of the target are predicted by using the current state of the target, and the state of the target at the next moment is obtained by combining the T3 model. Finally, simulation verification is carried out under various conditions. The simulation results show that the DKTP algorithm combines the advantages of data-driven and knowledge-driven, improves the interpretability of the algorithm, reduces the uncertainty, which can achieve high-precision trajectory prediction of ballistic missile in the boost phase. 展开更多
关键词 Ballistic missile Trajectory prediction The boost phase Data and knowledge driven The BP neural network
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通信干扰效能评估:q阶序对模糊集与CoCoSo-BM融合框架
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作者 宁晓燕 王翔辰 +1 位作者 杨健 陈增茂 《电子与信息学报》 北大核心 2025年第7期2062-2072,共11页
在现代电子战的通信对抗中,干扰效能评估能够为抗干扰策略的选择提供决策依据,是无人系统实现智能抗干扰的关键技术。借鉴数学统计领域中最新提出的CoCoSo(Combined Compromise Solution)算法思想,该文提出基于q阶序对模糊集和CoCoSo-B... 在现代电子战的通信对抗中,干扰效能评估能够为抗干扰策略的选择提供决策依据,是无人系统实现智能抗干扰的关键技术。借鉴数学统计领域中最新提出的CoCoSo(Combined Compromise Solution)算法思想,该文提出基于q阶序对模糊集和CoCoSo-BM的通信干扰效能评估方法。首先,根据通信系统与干扰的特点建立通信干扰效能评估指标体系,并采用层次分析法(AHP)与离差最大化法结合的方法确定组合权重。其次,提出采用q阶序对模糊集解决干扰效能评估维度单一的问题,并且引入BM(Bonferroni Mean)算子改进CoCoSo评估方法没有考虑参数权重的问题。最后,通过仿真实验验证了该方法在不同通信抗干扰技术与不同干扰条件下的效能评估有效性和对不同通信环境干扰效果的区分度、敏感度。 展开更多
关键词 干扰效能评估 CoCoSo算法 q阶序对模糊集 bm算子 组合权重
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Online task planning method of anti-ship missile based on rolling optimization 被引量:1
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作者 LU Faxing DAI Qiuyang +1 位作者 YANG Guang JIA Zhengrong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期720-731,共12页
Based on the wave attack task planning method in static complex environment and the rolling optimization framework, an online task planning method in dynamic complex environment based on rolling optimization is propos... Based on the wave attack task planning method in static complex environment and the rolling optimization framework, an online task planning method in dynamic complex environment based on rolling optimization is proposed. In the process of online task planning in dynamic complex environment,online task planning is based on event triggering including target information update event, new target addition event, target failure event, weapon failure event, etc., and the methods include defense area reanalysis, parameter space update, and mission re-planning. Simulation is conducted for different events and the result shows that the index value of the attack scenario after re-planning is better than that before re-planning and according to the probability distribution of statistical simulation method, the index value distribution after re-planning is obviously in the region of high index value, and the index value gap before and after re-planning is related to the degree of posture change. 展开更多
关键词 target allocation of anti-ship missile defense area rolling optimization task re-planning
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用于PON的低成本CMOS BM-TIA设计 被引量:1
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作者 赵婉青 夏翼飞 +5 位作者 李佳 徐颂秦 马帅哲 杨睿煊 耿莉 李丹 《光通信研究》 北大核心 2025年第1期52-58,共7页
【目的】在高速率无源光网络(PON)需求的快速增长下,低成本低噪声突发模式跨阻放大器(BM-TIA)成为其关键的制约因素。文章基于低成本40 nm互补金属氧化物半导体(CMOS)工艺,设计了一种适用于10吉比特对称无源光网络(XGS-PON)的快速建立... 【目的】在高速率无源光网络(PON)需求的快速增长下,低成本低噪声突发模式跨阻放大器(BM-TIA)成为其关键的制约因素。文章基于低成本40 nm互补金属氧化物半导体(CMOS)工艺,设计了一种适用于10吉比特对称无源光网络(XGS-PON)的快速建立低噪声BM-TIA,其可兼容12.5、10.0和2.5 Gbit/s 3种信号速率。【方法】为突破CMOS工艺的带宽和噪声瓶颈,TIA通过多级放大、输入电感均衡网络及提高电源电压的方法实现了要求的低噪声。采用前向放大器与反馈电阻共同调节的增益调节方式,实现了3档位的增益变化和速率变化。针对突发模式信号采用快速直流(DC)消除环路(AOC)来精准消除雪崩击穿二极管(APD)输入的DC电流,运用电荷分享技术加速失调消除环路的建立,并通过转换AOC环路时间常数的方法来抑制基线漂移。【结果】芯片采用40 nm CMOS工艺设计制造,裸片尺寸为945μm×945μm。芯片搭配商用10 Gbit/s APD进行同轴罐(TO-CAN)封装测试。测试结果表明,在12.5、10.0以及2.5 Gbit/s速率下,芯片的灵敏度分别为-29.7,-33.0和-37.6 dBm。在不同速率下,饱和输入光电流均可达2.5 mA,实现了24.7、28.2和32.8 dB的大输入动态范围。芯片的静态功耗为82.5 mW,在整个输入光功率范围内,突发模式下AOC的建立时间均小于23 ns。【结论】将文章所提芯片应用于XGS-PON,不但为基于CMOS工艺的低成本低噪声BM-TIA设计提供了借鉴,也对更高速率PON场景下的芯片设计具有指导意义。 展开更多
关键词 互补金属氧化物半导体工艺 10吉比特对称无源光网络 突发模式跨阻放大器 多速率兼容 快速建立
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Recorded recurrent deep reinforcement learning guidance laws for intercepting endoatmospheric maneuvering missiles
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作者 Xiaoqi Qiu Peng Lai +1 位作者 Changsheng Gao Wuxing Jing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期457-470,共14页
This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with u... This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with uncertainties and observation noise.The attack-defense engagement scenario is modeled as a partially observable Markov decision process(POMDP).Given the benefits of recurrent neural networks(RNNs)in processing sequence information,an RNN layer is incorporated into the agent’s policy network to alleviate the bottleneck of traditional deep reinforcement learning methods while dealing with POMDPs.The measurements from the interceptor’s seeker during each guidance cycle are combined into one sequence as the input to the policy network since the detection frequency of an interceptor is usually higher than its guidance frequency.During training,the hidden states of the RNN layer in the policy network are recorded to overcome the partially observable problem that this RNN layer causes inside the agent.The training curves show that the proposed RRTD3 successfully enhances data efficiency,training speed,and training stability.The test results confirm the advantages of the RRTD3-based guidance laws over some conventional guidance laws. 展开更多
关键词 Endoatmospheric interception missile guidance Reinforcement learning Markov decision process Recurrent neural networks
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Time-varying parameters estimation with adaptive neural network EKF for missile-dual control system
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作者 YUAN Yuqi ZHOU Di +1 位作者 LI Junlong LOU Chaofei 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期451-462,共12页
In this paper, a filtering method is presented to estimate time-varying parameters of a missile dual control system with tail fins and reaction jets as control variables. In this method, the long-short-term memory(LST... In this paper, a filtering method is presented to estimate time-varying parameters of a missile dual control system with tail fins and reaction jets as control variables. In this method, the long-short-term memory(LSTM) neural network is nested into the extended Kalman filter(EKF) to modify the Kalman gain such that the filtering performance is improved in the presence of large model uncertainties. To avoid the unstable network output caused by the abrupt changes of system states,an adaptive correction factor is introduced to correct the network output online. In the process of training the network, a multi-gradient descent learning mode is proposed to better fit the internal state of the system, and a rolling training is used to implement an online prediction logic. Based on the Lyapunov second method, we discuss the stability of the system, the result shows that when the training error of neural network is sufficiently small, the system is asymptotically stable. With its application to the estimation of time-varying parameters of a missile dual control system, the LSTM-EKF shows better filtering performance than the EKF and adaptive EKF(AEKF) when there exist large uncertainties in the system model. 展开更多
关键词 long-short-term memory(LSTM)neural network extended Kalman filter(EKF) rolling training time-varying parameters estimation missile dual control system
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BM3D-YOLOv8-s:前视声呐图像目标检测算法
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作者 陈美龙 赵新华 叶秀芬 《仪器仪表学报》 北大核心 2025年第2期234-246,共13页
前视声呐作为海洋探测的重要传感器之一,能够远距离探测水下目标,被广泛应用于目标检测和跟踪领域中。然而,声呐数据采集时受海洋环境噪声影响,噪声分布不均匀,使得声呐图像的目标探测精度低。采用传统卷积神经网络对前视声呐目标进行... 前视声呐作为海洋探测的重要传感器之一,能够远距离探测水下目标,被广泛应用于目标检测和跟踪领域中。然而,声呐数据采集时受海洋环境噪声影响,噪声分布不均匀,使得声呐图像的目标探测精度低。采用传统卷积神经网络对前视声呐目标进行跟踪时,因为声呐图像序列帧率较低、目标特征不清晰,容易出现目标丢失问题。针对前视声呐图像噪声污染严重的问题,结合前视声呐图像的特点,提出了一种改进的BM3D算法,减少3D转换处理的计算量,在基础估计的相似块匹配距离计算过程中,采用曼哈顿距离替代欧氏距离,更好地处理声呐图像中不同类型和强度的噪声;针对目标丢失问题,提出了基于YOLOv8-s改进网络的前视声呐图像目标检测算法,包括基于ConvNeXt的C2N改进算法、添加浅特征检测头和归一化Wasserstein距离(NWD)损失函数的改进。进行了声呐图像数据采集,并进行了实验验证。实验结果表明,改进后模型的准确率为87.2%,mAP0.5为85.4%。与改进前的YOLOv8-s模型相比,虽然模型大小只增加了4.6 MB,但是精度增加了5.1个百分点,mAP@0.5增加了4个百分点,对比其他检测模型实验结果,改进后的YOLOv8-s能够有效提升声呐图像的目标检测精度。 展开更多
关键词 前视声呐 噪声 bm3D 目标检测 YOLOv8-s
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核糖体生物合成因子BMS1对神经母细胞瘤细胞增殖的影响
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作者 郭金鑫 贾安娜 +4 位作者 战世佳 张瑶 张璇 郭永丽 常艳 《首都医科大学学报》 北大核心 2025年第2期296-305,共10页
目的探究核糖体生物合成因子BMS1在神经母细胞瘤(neuroblastoma,NB)细胞增殖中的功能及潜在机制。方法通过R2数据库分析BMS1表达与NB患儿临床特征的相关性;实时荧光定量聚合酶链式反应(real-time quantitative polymerase chain reactio... 目的探究核糖体生物合成因子BMS1在神经母细胞瘤(neuroblastoma,NB)细胞增殖中的功能及潜在机制。方法通过R2数据库分析BMS1表达与NB患儿临床特征的相关性;实时荧光定量聚合酶链式反应(real-time quantitative polymerase chain reaction,RT-qPCR)检测人神经母细胞瘤细胞SK-N-BE(2)、BE(2)-C、IMR-32和正常细胞hTERT RPE-1(人永生化视网膜上皮细胞)、IMR-90(人胚肺成纤维细胞)中BMS1 mRNA水平。利用小分子干扰RNA(small interfering RNA,siRNA)靶向瞬时敲低NB细胞SK-N-BE(2)、BE(2)-C和正常细胞hTERT RPE-1中BMS1 mRNA的表达,RT-qPCR检测BMS1敲低效果及细胞内MYCN mRNA和p53 mRNA水平,并通过结晶紫染色、实时无标记动态细胞分析技术(real time cellular analysis,RTCA)、克隆形成实验、免疫荧光等实验检测细胞增殖活性。结果分析R2数据库中GSE85047(NRC-283)和Westermann-144数据集发现BMS1在MYCN基因扩增的NB样本中表达水平显著高于MYCN基因非扩增的NB样本(P<0.05),且BMS1高表达的NB患儿总体生存率显著降低(P<0.05)。BMS1在NB细胞SK-N-BE(2)、BE(2)-C、IMR-32的mRNA表达水平显著高于正常细胞hTERT RPE-1、IMR-90(P<0.05)。靶向瞬时敲低NB细胞SK-N-BE(2)和BE(2)-C内BMS1导致细胞内MYCN mRNA表达水平下降(P<0.05),细胞的增殖能力和克隆形成能力显著下降(P<0.05),免疫荧光结果显示细胞增殖标志物Ki-67的表达量显著减少(P<0.05)。此外,与对照组相比,SK-N-BE(2)和BE(2)-C细胞中BMS1敲低组(siBMS1-1#和siBMS1-2#)的p53 mRNA水平显著升高(P<0.05)。然而,在正常细胞hTERT RPE-1内敲低BMS1,对细胞增殖无显著影响。结论BMS1在MYCN基因扩增的NB样本中表达上调,且BMS1高表达的NB患儿预后较差;干扰BMS1的表达可转录激活NB细胞内p53从而抑制NB细胞增殖。BMS1能够促进NB的增殖,有望成为NB潜在治疗靶点,尤其是MYCN基因扩增型NB。 展开更多
关键词 bmS1 神经母细胞瘤 细胞增殖 P53 MYCN
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Consecutive tracking for ballistic missile based on bearings-only during boost phase 被引量:6
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作者 Mei Liu Jianguo Yu +2 位作者 Ling Yang Lu Yao Yaosheng Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期700-707,共8页
This paper proposes a modified centralized shifted Rayleigh filter(MCSRF) algorithm for tracking boost phase of ballistic missile(BM) trajectory with a highly nonlinear dynamical model based on bearings-only.This ... This paper proposes a modified centralized shifted Rayleigh filter(MCSRF) algorithm for tracking boost phase of ballistic missile(BM) trajectory with a highly nonlinear dynamical model based on bearings-only.This paper contributes three folds.Firstly,the mathematical model of an MCSRF for multiple passive sensors is derived.Then,minimum entropy based onedimensional optimization search to adaptively adjust the probability of the different filters for real time state estimation is deployed.Finally,the unscented transform(UT) is introduced to resolve the asymmetric state estimation problem.Simulation results show that the proposed algorithm can consecutively track the BM precisely during the boost phase.In comparison with the unscented Kalman filter(UKF) algorithm,the proposed algorithm effectively reduces the tracking position and velocity root mean square(RMS) errors,which will make more sense for early precision interception. 展开更多
关键词 ballistic missile(bm) bearings-only tracking unscented transform(UT) asymmetric state estimation interacting multiple modes boost phase
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用于闪光图像消噪的改进BM3D方法
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作者 危才华 唐志鹏 +2 位作者 景越峰 管永红 刘进 《强激光与粒子束》 CAS CSCD 北大核心 2024年第10期61-68,共8页
高斯噪声是闪光图像中的主要噪声,将在密度反演等后续处理中被放大,严重影响密度重建及客体边界提取结果,因此,消高斯噪声是闪光图像消噪研究的重点内容。针对闪光照相图像噪声及照相客体轴旋转对称的特点,研究了基于三维块匹配滤波(Blo... 高斯噪声是闪光图像中的主要噪声,将在密度反演等后续处理中被放大,严重影响密度重建及客体边界提取结果,因此,消高斯噪声是闪光图像消噪研究的重点内容。针对闪光照相图像噪声及照相客体轴旋转对称的特点,研究了基于三维块匹配滤波(Block Matching and 3D Filtering,BM3D)的闪光照相图像消噪算法,针对闪光照相图像中难以获得更高质量相似块的缺陷,在不破坏噪声独立性的情况下,通过对含噪退化图像进行旋转与镜像操作,增加了提供相似块的图像来源。同时,通过引入图像块的灰度变换,降低了原有相似性要求中的灰度值要求,提高了形状相似的要求,增加了获得高质量相似块的能力。图像的消噪结果表明,由于相似块的质量得到保证,用于闪光图像消噪的改进BM3D方法取得了更好的消噪效果。 展开更多
关键词 闪光图像 高斯噪声 bm3D 消噪
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基于自适应BM3D的绝缘子缺陷检测图像降噪方法 被引量:1
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作者 时培明 袁群贸 +1 位作者 许学方 阚俊明 《计量学报》 CSCD 北大核心 2024年第8期1200-1208,共9页
由于拍摄环境的影响,获取的图像中常常混有噪声,极易影响绝缘子缺陷检测的准确性。针对该问题,提出了一种自适应BM3D降噪方法。首先,引入基于噪声水平与图像块协方差矩阵特征值的统计关系的噪声估计算法,解决原始BM3D算法需要先验知识... 由于拍摄环境的影响,获取的图像中常常混有噪声,极易影响绝缘子缺陷检测的准确性。针对该问题,提出了一种自适应BM3D降噪方法。首先,引入基于噪声水平与图像块协方差矩阵特征值的统计关系的噪声估计算法,解决原始BM3D算法需要先验知识的问题;其次,以峰值信噪比为目标函数,通过量子遗传算法得到绝缘子图像在各个噪声强度下的参数最优值,包括基础估计中的硬阈值参数、距离阈值和最终估计中的距离阈值;最后,以噪声强度为自变量,采用多项式拟合的方式得到上述3个参数的拟合曲线,从而得到各个噪声强度下算法的最佳参数组合,实现BM3D算法在不同噪声水平下的参数快速自适应。对比实验的结果表明所提出的方法在直观视觉和客观评价指标上优于其他方法。当噪声标准差为25时,所提出的方法相较于原始BM3D算法在峰值信噪比、结构相似性和边缘保留指数指标上均有所提升,尤其是边缘保留指数提升近20%。在提升降噪效果的同时能够保留更多边缘细节,这有助于提高后续绝缘子识别及缺陷检测的效果。 展开更多
关键词 电学计量 绝缘子缺陷检测 图像识别 图像降噪 bm3D算法 结构相似性
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BMS电路板多模块协同热-力耦合建模及仿真分析
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作者 何莉萍 原江鑫 李耀东 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期135-144,共10页
针对现有电动汽车电池管理系统(BMS)电路板研究仅仅考虑单一功能模块的温度场及其散热效果,缺乏考虑BMS多个功能模块在温度场和力场下的相互影响及协同效应的研究的情况,以某商用BMS电路板为研究对象,采用ANSYS构建了表征BMS多模块协同... 针对现有电动汽车电池管理系统(BMS)电路板研究仅仅考虑单一功能模块的温度场及其散热效果,缺乏考虑BMS多个功能模块在温度场和力场下的相互影响及协同效应的研究的情况,以某商用BMS电路板为研究对象,采用ANSYS构建了表征BMS多模块协同作用下的热-力耦合数值仿真分析模型并验证了其有效性.在此基础上,针对BMS电路板各功能模块温度场及热变形行为开展了数值仿真研究.结果表明:BMS电路板温度分布不均,最大温差达20.5℃.均衡模块存在积热,温度高达54.4℃.高温导致电路板组件发生热膨胀变形,同时电路板约束诱发均衡模块及供电模块边缘的贴片电阻出现热应力集中,两者共同作用致使BMS均衡模块、供电模块产生凸起翘曲变形,且Z轴热变形量随着温度升高而增大,最大变形量达9.5μm,应针对BMS电路板上积热模块开展散热优化设计. 展开更多
关键词 电动汽车 bmS 多模块 温度场 热变形 热-力耦合 仿真分析
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Boost-Phase ballistic missile trajectory estimation with ground based radar 被引量:11
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作者 Tang Yuyan Huang Peikang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期705-708,共4页
A conditional boost-phase trajectory estimation method based on ballistic missile (BM) information database and classification is developed to estimate and predict boos-phase BM trajectory. The main uncertain factor... A conditional boost-phase trajectory estimation method based on ballistic missile (BM) information database and classification is developed to estimate and predict boos-phase BM trajectory. The main uncertain factors to describe BM dynamics equation are reduced to the control law of trajectory pitch angle in boost-phase. After the BM mass at the beginning of estimation, the BM attack angle and the modification of engine thrust denoting BM acceleration are modeled reasonably, the boost-phase BM trajectory estimation with ground based radar is well realized. The validity of this estimation method is testified by computer simulation with a typical example. 展开更多
关键词 trajectory estimation boost-phase ground based radar ballistic missile.
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Time-varying fault-tolerant formation tracking based cooperative control and guidance for multiple cruise missile systems under actuator failures and directed topologies 被引量:10
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作者 XU Xingguang WEI Zhenyan +1 位作者 REN Zhang LI Shusheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期587-600,共14页
This paper studies time-varying fault-tolerant formation tracking problems for the multiple cruise missile system under directed topologies subjected to actuator failures. Firstly, the timevarying fault-tolerant forma... This paper studies time-varying fault-tolerant formation tracking problems for the multiple cruise missile system under directed topologies subjected to actuator failures. Firstly, the timevarying fault-tolerant formation tracking process for the multiple cruise missile system is divided into the guidance loop and the control loop. Then protocols are constructed to accomplish distributed fault-tolerant formation tracking in the guidance loop with the adaptive updating mechanism, in the condition where neither the knowledge about actuator malfunctions nor any global information of the communication topology remains available. Moreover, sufficient conditions to accomplish formation tracking are presented, and it is shown that the multiple cruise missile system can carry on the predefined time-varying fault-tolerant control (FTC) formation tracking through the active disturbances rejection controller (ADRC) and the proportion integration (PI) controller by the way of the fault-tolerant protocol utilizing the designed strategies, in the event of actuator failures. At last, numerical analysis and simulation are designed to verify the theoretical results. 展开更多
关键词 FAULT-TOLERANT formation tracking consensus-based CRUISE missile active disturbances REJECTION controller (ADRC)
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Analysis and improvement of missile three-loop autopilots 被引量:10
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作者 Lin Defu Fan Junfang Qi Zaikang Mou Yu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期844-851,共8页
The non-minimum phase feature of tail-controlled missile airframes is analyzed. Three selection strategies for desired performance indexes are presented. An acceleration autopilot design methodology based on output fe... The non-minimum phase feature of tail-controlled missile airframes is analyzed. Three selection strategies for desired performance indexes are presented. An acceleration autopilot design methodology based on output feedback and optimization is proposed. Performance and robustness comparisons between the two-loop and classical three-loop topologies are made. Attempts to improve the classical three-loop topology are discussed. Despite the same open-loop structure, the classical three-loop autopilot shows distinct characteristics from a two-loop autopilot with PI compensator. Both the two-loop and three-loop topologies can stabilize a static unstable missile. However, the finite actuator resource is the crucial factor dominating autopilot function. 展开更多
关键词 missile control three-loop autopilot output feedback fin resource non-minimum phase system
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Study on Missile Intelligent Fault Diagnosis System Based on Fuzzy NN Expert System 被引量:7
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作者 Yang Jun Feng Zhensheng +1 位作者 Zhang Xien & Liu Pengyuan Dept. of Missile Engineering, Ordnance Engineering College, Shijiazhuang 050003, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第1期82-87,共6页
In order to study intelligent fault diagnosis methods based on fuzzy neural network (NN) expert system and build up intelligent fault diagnosis for a type of missile weapon system, the concrete implementation of a fuz... In order to study intelligent fault diagnosis methods based on fuzzy neural network (NN) expert system and build up intelligent fault diagnosis for a type of missile weapon system, the concrete implementation of a fuzzy NN fault diagnosis expert system is given in this paper. Based on thorough research of knowledge presentation, the intelligent fault diagnosis system is implemented with artificial intelligence for a large-scale missile weapon equipment. The method is an effective way to perform fuzzy fault diagnosis. Moreover, it provides a new way of the fault diagnosis for large-scale missile weapon equipment. 展开更多
关键词 Artificial intelligence Electric fault location Expert systems Fuzzy sets missiles Neural networks
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Storage reliability assessment model based on competition failure of multi-components in missile 被引量:11
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作者 Yunxiang Chen Qiang Zhang +1 位作者 Zhongyi Cai Lili Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期606-616,共11页
The degradation data of multi-components in missile is derived by periodical testing. How to use these data to assess the storage reliability (SR) of the whole missile is a difficult problem in current research. An SR... The degradation data of multi-components in missile is derived by periodical testing. How to use these data to assess the storage reliability (SR) of the whole missile is a difficult problem in current research. An SR assessment model based on competition failure of multi-components in missile is proposed. By analyzing the missile life profile and its storage failure feature, the key components in missile are obtained and the characteristics voltage is assumed to be its key performance parameter. When the voltage testing data of key components in missile are available, a state space model (SSM) is applied to obtain the whole missile degradation state, which is defined as the missile degradation degree (DD). A Wiener process with the time-scale model (TSM) is applied to build the degradation failure model with individual variability and nonlinearity. The Weibull distribution and proportional risk model are applied to build an outburst failure model with performance degradation effect. Furthermore, a competition failure model with the correlation between degradation failure and outburst failure is proposed. A numerical example with a set of missiles in storage is analyzed to demonstrate the accuracy and superiority of the proposed model. 展开更多
关键词 competition failure model storage reliability (SR) missile degradation degree (DD) proportional risk model individual variability
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Novel backstepping design for blended aero and reaction-jet missile autopilot 被引量:7
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作者 Liu Zhong Jia Xiaohong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期148-153,共6页
The advanced missile uses blended control of nero-fin and reaction-jet to improve missile maneuverability. The blended control design, which is multi-inputs and multi-outputs (MIMO), severe nonlinear, and model unce... The advanced missile uses blended control of nero-fin and reaction-jet to improve missile maneuverability. The blended control design, which is multi-inputs and multi-outputs (MIMO), severe nonlinear, and model uncertain, is much more complex than conventional nero-fin control. A novel nonlinear backstepping control approach is proposed to design the blended autopilot. Missile model is reformed to a new one by state reconstruction technique so that it is easy to be handled by the backstepping method. Then a Lyapunov function is chosen to avoid oscillation caused in normal backstepping way when control parameters are mismatched. In distribution of both inputs, optimal energy logic is proposed. In addition, a fuzzy cerebellar model articulation controller (FCMAC) neural network is used to guarantee controller robustness to uncertainties. Finally, simulation results demonstrate the efficiency and advantages of the proposed method. 展开更多
关键词 missile control blended aero-fin and reaction-jet control nonlinear backstepping optimal enery logic.
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