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基于PCA-LM的空战目标威胁评估

火力与指挥控制 2024年第2期49卷 63-68页

作者：李战武张帅奚之飞李游李钢空军工程大学航空工程学院西安710038 解放军93987部队西宁810007

空战过程中态势瞬息万变,获取敌目标的威胁是我方取得攻击占位优势和采取战术规避的前提条件。提出主成分分析法和阻尼最小二乘法相结合的回归模型对目标的威胁进行评估。利用主成分分析法,分析指标之间的相关性,转化成相互独立的分量,... 详细信息

空战过程中态势瞬息万变,获取敌目标的威胁是我方取得攻击占位优势和采取战术规避的前提条件。提出主成分分析法和阻尼最小二乘法相结合的回归模型对目标的威胁进行评估。利用主成分分析法,分析指标之间的相关性,转化成相互独立的分量,确定主成分分量,重构目标威胁评估体系;对目标威胁与主成分分量进行回归分析,利用阻尼最小二乘法对回归模型参数进行估计,得到主成分分量与目标威胁之间的统计关系;利用目标威胁估计值与实际值之间的误差大小,验证了回归模型的有效性。消除了指标之间的相关性对评估结果的影响,提高了评估结果的客观性,解决了传统评估方法忽略指标之间耦合性的问题。

关键词：主成分分析阻尼最小二乘法回归分析指标相关性重构

Target maneuver trajectory prediction based on RBF neural network optimized by hybrid algorithm

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Journal of Systems Engineering and Electronics 2021年第2期32卷 498-516页

作者： xi zhifei XU An KOU Yingxin LI Zhanwu YANG Aiwu Aeronautics Engineering College Air Force Engineering UniversityXi’an 710038China

Target maneuver trajectory prediction plays an important role in air combat situation awareness and threat *** solve the problem of low prediction accuracy of the traditional prediction method and model,a target maneuver trajectory prediction model based on phase space reconstruction-radial basis function(PSR-RBF)neural network is established by combining the characteristics of trajectory with time *** order to further improve the prediction performance of the model,the rival penalized competitive learning(RPCL)algorithm is introduced to determine the structure of RBF,the Levenberg-Marquardt(LM)and the hybrid algorithm of the improved particle swarm optimization(IPSO)algorithm and the k-means are introduced to optimize the parameter of RBF,and a PSR-RBF neural network is *** independent method of 3D coordinates of the target maneuver trajectory is proposed,and the target manuver trajectory sample data is constructed by using the training data selected in the air combat maneuver instrument(ACMI),and the maneuver trajectory prediction model based on the PSR-RBF neural network is *** order to verify the precision and real-time performance of the trajectory prediction model,the simulation experiment of target maneuver trajectory is *** results show that the prediction performance of the independent method is better,and the accuracy of the PSR-RBF prediction model proposed is *** prediction confirms the effectiveness and applicability of the proposed method and model.

关键词： trajectory prediction k-means improved particle swarm optimization(IPSO) Levenberg-Marquardt(LM) radial basis function(RBF)neural network

An online ensemble semi-supervised classification framework for air combat target maneuver recognition

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Chinese Journal of Aeronautics 2023年第6期36卷 340-360页

作者： zhifei xi Yue LYU Yingxin KOU Zhanwu LI You LI Air Defense and Antimissile School Air Force Engineering UniversityXi'an 710051China

Online target maneuver recognition is an important prerequisite for air combat situation recognition and maneuver *** target maneuver recognition methods adopt mainly supervised learning methods and assume that many sample labels are ***,in real-world applications,manual sample labeling is often time-consuming and *** addition,airborne sensors collecting target maneuver trajectory information in data streams often cannot process information in real *** solve these problems,in this paper,an air combat target maneuver recognition model based on an online ensemble semi-supervised classification framework based on online learning,ensemble learning,semi-supervised learning,and Tri-training algorithm,abbreviated as Online Ensemble Semi-supervised Classification Framework(OESCF),is *** framework is divided into four parts:basic classifier offline training stage,online recognition model initialization stage,target maneuver online recognition stage,and online model update ***,based on the improved Tri-training algorithm and the fusion decision filtering strategy combined with disagreement,basic classifiers are trained offline by making full use of labeled and unlabeled sample ***,the dynamic density clustering algorithm of the target maneuver is performed,statistical information of each cluster is calculated,and a set of micro-clusters is obtained to initialize the online recognition ***,the ensemble K-Nearest Neighbor(KNN)-based learning method is used to recognize the incoming target maneuver trajectory ***,to further improve the accuracy and adaptability of the model under the condition of high dynamic air combat,the parameters of the model are updated online using error-driven representation learning,exponential decay function and basic classifier obtained in the offline training *** experimental results on several University of California Irvine(UCI)datasets an

关键词： Ensemble learning Maneuver recognition Online learning Semi-supervised learning Tri-training

An air combat maneuver pattern extraction based on time series segmentation and clustering analysis

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Defence technology 2024年第6期 149页

作者： zhifei xi Yingxin Kou Zhanwu Li Yue Lv You Li

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飞机结构X射线裂纹图像智能评定

航空工程进展 2024年第1期15卷 97-104页

作者：贾文博汪洪量奚之飞樊俊铃杨胜春张伟赵延广中国飞机强度研究所强度与结构完整性全国重点实验室西安710065 国营芜湖机械厂芜湖241000 大连理工大学工业装备结构分析国家重点实验室大连116023

飞机结构X射线图像评定过程存在复杂背景下裂纹分割不准确、检出难等问题。基于高效层聚合网络提出一种飞机结构X射线裂纹图像智能评定模型(ELAN-Seg),将ELAN-Seg模型和DeepLabv3+模型的射线图像裂纹分割能力进行对比,结合图像处理技术... 详细信息

飞机结构X射线图像评定过程存在复杂背景下裂纹分割不准确、检出难等问题。基于高效层聚合网络提出一种飞机结构X射线裂纹图像智能评定模型(ELAN-Seg),将ELAN-Seg模型和DeepLabv3+模型的射线图像裂纹分割能力进行对比,结合图像处理技术对模型分割的裂纹长度进行评估,利用飞机强度试验及外场维护过程采集的X射线图像对模型进行验证。结果表明:分割的最小裂纹长度约为3 mm,ELAN-Seg模型对复杂背景射线图像裂纹分割更加准确,裂纹漏检率小于3.8%,该模型具有工程适用性。

关键词： X射线裂纹图像高效层聚合网络注意力机制智能评定

Autophagy and circadian rhythms:interactions and clinical implications

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BIOCELL 2024年第1期48卷 33-45页

作者： TIANKAI DI zhifei ZHOU FEN LIU YUJIANG CHEN LULU WANG State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Clinical Research Center for Oral DiseasesDepartment of Pediatric DentistrySchool of StomatologyThe Fourth Military Medical UniversityXi’an710032China Department of Stomatology The 969th HospitalJoint Logistics Support Force of the Chinese People’s Liberation ArmyHohhot010000China Department of Stomatology General Hospital of Tibetan Military CommandLhasa850000China Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research Clinical Research Center of Shaanxi Province for Dental and Maxillofacial DiseasesDepartment of Pediatric DentistryCollege of StomatologyXi’an Jiaotong UniversityXi’an710000China Department of Neurobiology and Institute of Neurosciences School of Basic MedicineFourth Military Medical UniversityXi’an710032China

Autophagy is a widespread biological process that controls cellular growth,survival,development,and *** rhythm is a recurring reaction of living organisms and behaviors to variations in surrounding brightness and *** of the fundamental physiological processes in mammals,such as the sleep-wake pattern and the rhythm of nutrition and energy metabolism,are governed by circadian *** has indicated that autophagy exhibits a specific circadian pattern in both normal and abnormal *** can modulate circadian rhythms by breaking down proteins that regulate the circadian *** potential regulatory connection between the two has been a popular subject of clinical and fundamental *** the interaction between circadian rhythm and autophagy could potentially lead to the development of novel approaches for disease treatment in the *** present analysis presented a summary of the molecular processes implicated in the interplay between autophagy and circadian rhythm,as well as the pathological importance of the disrupted regulatory association between these two phenomena.

关键词： Autophagy Circadian rhythms Mechanism Application

基于改进LS-ESPRIT算法的GTD模型参数估计与RCS重构

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电子与信息学报 2020年第10期42卷 2493-2499页

作者：张小宽郑舒予奚之飞葛启超宗彬锋中国人民解放军空军工程大学防空反导学院西安710051 中国人民解放军空军工程大学研究生院西安710051

针对传统LS-ESPRIT算法在估计GTD模型参数时抗噪效果差,估计精度不高这一问题,该文提出了一种改进的LS-ESPRT算法,有效地提高了算法的参数估计性能与抗噪性。首先,根据雷达目标的回波数据构建Hankel矩阵;其次,采用核范数凸优化方法对上... 详细信息

针对传统LS-ESPRIT算法在估计GTD模型参数时抗噪效果差,估计精度不高这一问题,该文提出了一种改进的LS-ESPRT算法,有效地提高了算法的参数估计性能与抗噪性。首先,根据雷达目标的回波数据构建Hankel矩阵;其次,采用核范数凸优化方法对上述Hankel矩阵进行降噪处理,得到低秩的重构Hankel矩阵;最后,利用传统的LS-ESPRIT算法对降噪后的数据进行处理,估计出GTD模型参数。基于改进算法与传统算法分别得到重构RCS,并针对不同带宽对参数估计精度的影响作以仿真探究。仿真结果表明,与传统LS-ESPRIT算法与传统TLS-ESPRIT算法相比,改进LS-ESPRIT算法的参数估计性能更高,抗噪性更强,且重构RCS的幅值与相角误差更小。对不同带宽下的参数估计精度也进行了探究,并得出:带宽越大,估计精度越高。

关键词：散射中心 GTD模型凸优化处理改进的LS-ESPRIT算法 RCS重构

基于改进GRA-TOPSIS的空战威胁评估

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北京航空航天大学学报 2020年第2期46卷 388-397页

作者：奚之飞徐安寇英信李战武杨爱武空军工程大学航空工程学院西安710038 西北工业大学电子信息学院西安710072

针对在确定空战威胁评估指标权重时,未考虑指标间的耦合性以及客观赋权法不能从逻辑视角体现指标相对评价对象真正的重要程度的问题,提出了一种基于灰色关联度、灰色关联深度的极大熵模型初步确定权值,再根据指标间灰色关联度以及确定... 详细信息

针对在确定空战威胁评估指标权重时,未考虑指标间的耦合性以及客观赋权法不能从逻辑视角体现指标相对评价对象真正的重要程度的问题,提出了一种基于灰色关联度、灰色关联深度的极大熵模型初步确定权值,再根据指标间灰色关联度以及确定的解耦阈值修正权值的方法。为了克服灰色关联分析法(GRA)和理想点接近法(TOPSIS)的缺点,提出了一种基于GRA-TOPSIS的目标威胁评估方法。首先,通过实例对比分析了指标采用数学模型与模糊处理后,对目标威胁评估结果的影响;其次,对比分析了采用GRA、TOPSIS以及GRA-TOPSIS、数学模型得出的目标威胁评估结果;最后,考虑不同决策者的主观偏好,得出不同的目标威胁评估结果。通过仿真验证了所提方法的有效性以及科学性。

关键词：灰色关联深度指标间灰色关联度灰色关联分析法-理想点接近法(GRA-TOPSIS) 极大熵分辨系数

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基于RS-CRITIC的空战目标威胁评估

北京航空航天大学学报 2020年第12期46卷 2357-2365页

作者：杨爱武李战武徐安吕跃奚之飞空军工程大学航空工程学院西安710038

针对不确定信息下的空战目标威胁评估问题,提出了一种基于粗糙集(RS)理论和指标重要性相关(CRITIC)法的目标威胁评估模型。首先,通过CRITIC法确定准确信息下的目标威胁值,利用数据挖掘(MD)启发式算法求解最佳分割集合,将目标威胁值离散... 详细信息

针对不确定信息下的空战目标威胁评估问题,提出了一种基于粗糙集(RS)理论和指标重要性相关(CRITIC)法的目标威胁评估模型。首先,通过CRITIC法确定准确信息下的目标威胁值,利用数据挖掘(MD)启发式算法求解最佳分割集合,将目标威胁值离散化处理后替代粗糙集决策信息系统中的决策属性。其次,基于构建的完备粗糙集决策信息系统,通过决策矩阵实现属性约简和目标威胁评估最小决策规则提取。最后,将规则应用于不确定信息下的目标威胁评估。仿真结果表明:所提模型能够实现信息缺失下的目标威胁评估,减少了主观因素和先验知识的影响,扩展了粗糙集理论应用范围。

关键词：威胁评估粗糙集(RS) 指标重要性相关(CRITIC)法决策规则不确定信息