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Application of Self-Organizing Feature Map Neural Network Based on K-means Clustering in Network Intrusion Detection 被引量:5
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作者 Ling Tan Chong Li +1 位作者 Jingming Xia Jun Cao 《Computers, Materials & Continua》 SCIE EI 2019年第7期275-288,共14页
Due to the widespread use of the Internet,customer information is vulnerable to computer systems attack,which brings urgent need for the intrusion detection technology.Recently,network intrusion detection has been one... Due to the widespread use of the Internet,customer information is vulnerable to computer systems attack,which brings urgent need for the intrusion detection technology.Recently,network intrusion detection has been one of the most important technologies in network security detection.The accuracy of network intrusion detection has reached higher accuracy so far.However,these methods have very low efficiency in network intrusion detection,even the most popular SOM neural network method.In this paper,an efficient and fast network intrusion detection method was proposed.Firstly,the fundamental of the two different methods are introduced respectively.Then,the selforganizing feature map neural network based on K-means clustering(KSOM)algorithms was presented to improve the efficiency of network intrusion detection.Finally,the NSLKDD is used as network intrusion data set to demonstrate that the KSOM method can significantly reduce the number of clustering iteration than SOM method without substantially affecting the clustering results and the accuracy is much higher than Kmeans method.The Experimental results show that our method can relatively improve the accuracy of network intrusion and significantly reduce the number of clustering iteration. 展开更多
关键词 K-means clustering self-organizing feature map neural network network security intrusion detection NSL-KDD data set
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English-Chinese Neural Machine Translation Based on Self-organizing Mapping Neural Network and Deep Feature Matching
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作者 Shu Ma 《IJLAI Transactions on Science and Engineering》 2024年第3期1-8,共8页
The traditional Chinese-English translation model tends to translate some source words repeatedly,while mistakenly ignoring some words.Therefore,we propose a novel English-Chinese neural machine translation based on s... The traditional Chinese-English translation model tends to translate some source words repeatedly,while mistakenly ignoring some words.Therefore,we propose a novel English-Chinese neural machine translation based on self-organizing mapping neural network and deep feature matching.In this model,word vector,two-way LSTM,2D neural network and other deep learning models are used to extract the semantic matching features of question-answer pairs.Self-organizing mapping(SOM)is used to classify and identify the sentence feature.The attention mechanism-based neural machine translation model is taken as the baseline system.The experimental results show that this framework significantly improves the adequacy of English-Chinese machine translation and achieves better results than the traditional attention mechanism-based English-Chinese machine translation model. 展开更多
关键词 Chinese-English translation model Self-organizing mapping neural network Deep feature matching Deep learning
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An improved de-interleaving algorithm of radar pulses based on SOFM with self-adaptive network topology 被引量:1
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作者 JIANG Wen FU Xiongjun +1 位作者 CHANG Jiayun QIN Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期712-721,共10页
As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. As interleaved radar pulses become more complex and denser, intelligent classification of radar signal... As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. As interleaved radar pulses become more complex and denser, intelligent classification of radar signals has become very important. The self-organizing feature map(SOFM) is an excellent artificial neural network, which has huge advantages in intelligent classification of complex data. However, the de-interleaving process based on SOFM is faced with the problems that the initialization of the map size relies on prior information and the network topology cannot be adaptively adjusted. In this paper, an SOFM with self-adaptive network topology(SANT-SOFM) algorithm is proposed to solve the above problems. The SANT-SOFM algorithm first proposes an adaptive proliferation algorithm to adjust the map size, so that the initialization of the map size is no longer dependent on prior information but is gradually adjusted with the input data. Then,structural optimization algorithms are proposed to gradually optimize the topology of the SOFM network in the iterative process,constructing an optimal SANT. Finally, the optimized SOFM network is used for de-interleaving radar signals. Simulation results show that SANT-SOFM could get excellent performance in complex EW environments and the probability of getting the optimal map size is over 95% in the absence of priori information. 展开更多
关键词 de-interleaving self-organizing feature map(SOFM) self-adaptive network topology(SANT)
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Fast and Accurate Machine Learning Inverse Lithography Using Physics Based Feature Maps and Specially Designed DCNN
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作者 Xuelong Shi Yan Yan +4 位作者 Tao Zhou Xueru Yu Chen Li Shoumian Chen Yuhang Zhao 《Journal of Microelectronic Manufacturing》 2020年第4期51-58,共8页
Inverse lithography technology(ILT)is intended to achieve optimal mask design to print a lithography target for a given lithography process.Full chip implementation of rigorous inverse lithography remains a challengin... Inverse lithography technology(ILT)is intended to achieve optimal mask design to print a lithography target for a given lithography process.Full chip implementation of rigorous inverse lithography remains a challenging task because of enormous computational resource requirements and long computational time.To achieve full chip ILT solution,attempts have been made by using machine learning techniques based on deep convolution neural network(DCNN).The reported input for such DCNN is the rasterized images of the lithography target;such pure geometrical input requires DCNN to possess considerable number of layers to learn the optical properties of the mask,the nonlinear imaging process,and the rigorous ILT algorithm as well.To alleviate the difficulties,we have proposed the physics based optimal feature vector design for machine learning ILT in our early report.Although physics based feature vector followed by feedforward neural network can provide the solution to machine learning ILT,the feature vector is long and it can consume considerable amount of memory resource in practical implementation.To improve the resource efficiency,we proposed a hybrid approach in this study by combining first few physics based feature maps with a specially designed DCNN structure to learn the rigorous ILT algorithm.Our results show that this approach can make machine learning ILT easy,fast and more accurate. 展开更多
关键词 Optimal feature maps inverse lithography technology(ILT) deep convolution neural network(DCNN).
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An Emotion Analysis Method Using Multi-Channel Convolution Neural Network in Social Networks 被引量:2
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作者 Xinxin Lu Hong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第10期281-297,共17页
As an interdisciplinary comprehensive subject involving multidisciplinary knowledge,emotional analysis has become a hot topic in psychology,health medicine and computer science.It has a high comprehensive and practica... As an interdisciplinary comprehensive subject involving multidisciplinary knowledge,emotional analysis has become a hot topic in psychology,health medicine and computer science.It has a high comprehensive and practical application value.Emotion research based on the social network is a relatively new topic in the field of psychology and medical health research.The text emotion analysis of college students also has an important research significance for the emotional state of students at a certain time or a certain period,so as to understand their normal state,abnormal state and the reason of state change from the information they wrote.In view of the fact that convolutional neural network cannot make full use of the unique emotional information in sentences,and the need to label a large number of highquality training sets for emotional analysis to improve the accuracy of the model,an emotional analysismodel using the emotional dictionary andmultichannel convolutional neural network is proposed in this paper.Firstly,the input matrix of emotion dictionary is constructed according to the emotion information,and the different feature information of sentences is combined to form different network input channels,so that the model can learn the emotion information of input sentences from various feature representations in the training process.Then,the loss function is reconstructed to realize the semi supervised learning of the network.Finally,experiments are carried on COAE 2014 and self-built data sets.The proposed model can not only extract more semantic information in emotional text,but also learn the hidden emotional information in emotional text.The experimental results show that the proposed emotion analysis model can achieve a better classification performance.Compared with the best benchmark model gram-CNN,the F1 value can be increased by 0.026 in the self-built data set,and it can be increased by 0.032 in the COAE 2014 data set. 展开更多
关键词 Emotion analysis model emotion dictionary convolution neural network semi supervised learning deep learning pooling feature feature mapping
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特征图组合的双流CNN手指关节角度连续运动预测方法研究
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作者 武岩 曹崇莉 +2 位作者 李奇 姬鹏辉 张航 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第11期119-128,共10页
针对基于表面肌电(surface electromyography,sEMG)信号手指关节角度连续运动预测时序信息提取不足、预测准确率较低的问题,提出了一种基于特征图组合(feature map combinations,FMC)的双流卷积神经网络(dual-stream convolutional neur... 针对基于表面肌电(surface electromyography,sEMG)信号手指关节角度连续运动预测时序信息提取不足、预测准确率较低的问题,提出了一种基于特征图组合(feature map combinations,FMC)的双流卷积神经网络(dual-stream convolutional neural network,DCNN)预测方法。提取sEMG信号的特征信息,采用滑动窗方式将特征信息进行特征图组合,表达特征的时间连贯性以提取sEMG信号的时序信息,通过DCNN网络在时间、空间维度对组合后的特征图提取深层特征,提高手指关节角度连续运动预测效果。在NinaPro-DB8数据集上进行实验,结果表明:在3类不同自由度(18个、5个、3个)的相关方法比较中,健康受试者的R2值分别提高了7.9%、16.8%和17.8%;截肢受试者的R2值分别提高了9.6%、14.3%和10.3%。 展开更多
关键词 SEMG 连续运动预测 特征图组合 双流卷积神经网络
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Self-organizing feature map neural network classification of the ASTER data based on wavelet fusion 被引量:7
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作者 HASI Bagan MA Jianwen LI Qiqing HAN Xiuzhen LIU Zhili 《Science China Earth Sciences》 SCIE EI CAS 2004年第7期651-658,共8页
Most methods for classification of remote sensing data are based on the statistical parameter evaluation with the assumption that the samples obey the normal distribution. How-ever, more accurate classification result... Most methods for classification of remote sensing data are based on the statistical parameter evaluation with the assumption that the samples obey the normal distribution. How-ever, more accurate classification results can be obtained with the neural network method through getting knowledge from environments and adjusting the parameter (or weight) step by step by a specific measurement. This paper focuses on the double-layer structured Kohonen self-organizing feature map (SOFM), for which all neurons within the two layers are linked one another and those of the competition layers are linked as well along the sides. Therefore, the self-adapting learning ability is improved due to the effective competition and suppression in this method. The SOFM has become a hot topic in the research area of remote sensing data classi-fication. The Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER) is a new satellite-borne remote sensing instrument with three 15-m resolution bands and three 30-m resolution bands at the near infrared. The ASTER data of Dagang district, Tianjin Munici-pality is used as the test data in this study. At first, the wavelet fusion is carried out to make the spatial resolutions of the ASTER data identical; then, the SOFM method is applied to classifying the land cover types. The classification results are compared with those of the maximum likeli-hood method (MLH). As a consequence, the classification accuracy of SOFM increases about by 7% in general and, in particular, it is almost as twice as that of the MLH method in the town. 展开更多
关键词 classification WAVELET fusion SELF-ORGANIZING neural network feature map (SOFM) ASTER data.
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无人机双目视觉鲁棒定位方法
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作者 杨欣 杨忠 +3 位作者 张驰 卓浩泽 廖禄伟 薛八阳 《应用科技》 CAS 2024年第4期43-50,共8页
无人机(unmanned aerial vehicle,UAV)在全球定位系统(global positioning system,GPS)信号拒止环境中的应用受到限制,传统视觉同步定位与建图(simultaneous localization and mapping,SLAM)技术一定程度上解决了该问题,但在动态场景和... 无人机(unmanned aerial vehicle,UAV)在全球定位系统(global positioning system,GPS)信号拒止环境中的应用受到限制,传统视觉同步定位与建图(simultaneous localization and mapping,SLAM)技术一定程度上解决了该问题,但在动态场景和弱纹理场景中定位精度较差。针对该问题提出一种基于双目视觉的多场景鲁棒SLAM方法,重点考虑了真实环境中的动态和弱纹理2类具有挑战性的场景,利用双目相机为UAV在动态和弱纹理场景中提供位姿信息。针对动态场景利用掩膜基于区域的卷积神经网络(mask region-based convolutional neural network,Mask R-CNN)分割潜在动态内容并剔除动态特征,通过计算稠密光流同步相邻帧的掩膜,减小了掩膜的计算成本。对于弱纹理场景,在传统SLAM算法使用的点特征基础上融合了线特征,充分利用了环境中的结构特征。数值模拟和仿真实验证明了本文算法具有更高的鲁棒性和精确性。 展开更多
关键词 无人机定位 双目相机 同步定位与建图 掩模基于区域的卷积神经网络 动态剔除 点线特征 重投影误差 位姿优化
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Morphological self-organizing feature map neural network with applications to automatic target recognition
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作者 张世俊 敬忠良 李建勋 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第1期12-15,共4页
The rotation invariant feature of the target is obtained using the multi-direction feature extraction property of the steerable filter. Combining the morphological operation top-hat transform with the self-organizing ... The rotation invariant feature of the target is obtained using the multi-direction feature extraction property of the steerable filter. Combining the morphological operation top-hat transform with the self-organizing feature map neural network, the adaptive topological region is selected. Using the erosion operation, the topological region shrinkage is achieved. The steerable filter based morphological self-organizing feature map neural network is applied to automatic target recognition of binary standard patterns and real world infrared sequence images. Compared with Hamming network and morphological shared-weight networks respectively, the higher recognition correct rate, robust adaptability, quick training, and better generalization of the proposed method are achieved. 展开更多
关键词 feature extraction Image processing neural networks Self organizing maps Signal filtering and prediction
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基于轻量级CNN的视觉SLAM快速回环检测算法
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作者 蒋经纬 吉月辉 +1 位作者 刘俊杰 高强 《计算机仿真》 2024年第8期182-188,共7页
传统基于卷积神经网络(Convolutional Neural Network,CNN)的视觉同步定位与地图构建(Simultaneous Localization and Mapping,SLAM)系统回环检测目前准确率和召回率较高,但其存在特征提取时间较长和特征向量维度过高导致计算量较大等... 传统基于卷积神经网络(Convolutional Neural Network,CNN)的视觉同步定位与地图构建(Simultaneous Localization and Mapping,SLAM)系统回环检测目前准确率和召回率较高,但其存在特征提取时间较长和特征向量维度过高导致计算量较大等问题。针对上述问题,结合轻量级卷积神经网络MobileNetV3和PCA降维算法,提出了一种基于深度学习的快速回环检测算法。基于MobileNetV3进行特征提取并构建特征矩阵,运用PCA降维算法完成降维以提升运行速度,使用余弦相似度计算各个特征向量间的相似性,并取最大值与给定阈值比较判断是否构成回环。最后,使用New College和City Centre两个公开的数据集验证算法的性能。实验结果表明,相较于传统的CNN回环检测方法,提出的算法在保证准确率和召回率的同时,运行速度更快,较好的满足了视觉SLAM系统准确性和实时性的要求。 展开更多
关键词 同步定位与建图 回环检测 卷积神经网络 主成分分析 图像特征提取
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基于mRMR-SOM的异步电机轴承故障诊断研究
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作者 刘文 周智勇 蔡巍 《机电工程》 北大核心 2024年第1期90-98,共9页
针对异步电机轴承故障诊断问题,提出了一种融合最大相关最小冗余特征选择算法(mRMR)和自组织映射神经网络(SOM)的故障诊断方法,并将其应用于轴承故障诊断的不同阶段。首先,在实验室环境下搭建了异步电机故障诊断试验平台,在不同电机状... 针对异步电机轴承故障诊断问题,提出了一种融合最大相关最小冗余特征选择算法(mRMR)和自组织映射神经网络(SOM)的故障诊断方法,并将其应用于轴承故障诊断的不同阶段。首先,在实验室环境下搭建了异步电机故障诊断试验平台,在不同电机状态下分别采集振动、电流和电压信号,利用统计学方法获取了高维混合特征集;然后,以互信息为背景,利用mRMR根据特征与状态标签间的相关性和特征间的冗余性,筛选了具备强区分能力的特征,以避免计算冗余和后验诊断性能下降;最后,采用SOM对异步电机健康和轴承故障状态进行了分类识别,验证了SOM对异步电机轴承故障诊断的有效性,以及mRMR对故障诊断结果的影响。研究结果表明:基于mRMR-SOM的异步电机轴承故障诊断方法能够准确地区分健康和故障状态,测试集分类准确率达到89%;使用mRMR特征筛选能够将154维特征降低至17维,缩短23.5%的网络收敛时间,并将分类准确率由89%提升至98%;试验结果验证了基于mRMR-SOM的异步电机轴承故障诊断方法对于异步电机轴承故障诊断问题的有效性,且证实其具备良好的诊断效果。 展开更多
关键词 自组织映射神经网络 最大相关最小冗余特征选择算法 互信息 特征降维 特征选择 神经网络算法 U矩阵
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基于卷积神经网络的无人机遥感测绘图像特征提取方法
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作者 马宏平 《移动信息》 2024年第6期257-259,共3页
在地质勘探学领域,无人机遥感技术已成为获取地表数据的重要手段,而卷积神经网络(CNN)因其出色的图像处理能力被广泛应用于图像特征提取。文中介绍了一种基于卷积神经网络的无人机遥感测绘图像特征提取方法,分析了CNN的基本概念与结构... 在地质勘探学领域,无人机遥感技术已成为获取地表数据的重要手段,而卷积神经网络(CNN)因其出色的图像处理能力被广泛应用于图像特征提取。文中介绍了一种基于卷积神经网络的无人机遥感测绘图像特征提取方法,分析了CNN的基本概念与结构、无人机遥感图像的特征类型、网络结构设计、数据预处理、特征提取及特征融合过程,旨在提高地质勘探中无人机遥感图像分析的自动化和准确性。 展开更多
关键词 卷积神经网络 无人机 遥感测绘图像特征提取
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量子自组织特征映射神经网络
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作者 叶梓 《福建电脑》 2024年第1期21-26,共6页
自组织特征映射是典型的无监督神经网络算法。它运用竞争学习策略实现数据分类。然而当网络中神经元个数为多项式时,自组织特征映射算法训练容易受到计算力挑战。为了降低算法训练的时间复杂度,本文提出了一个量子经典混合的自组织特征... 自组织特征映射是典型的无监督神经网络算法。它运用竞争学习策略实现数据分类。然而当网络中神经元个数为多项式时,自组织特征映射算法训练容易受到计算力挑战。为了降低算法训练的时间复杂度,本文提出了一个量子经典混合的自组织特征映射神经网络算法,利用量子叠加性和量子纠缠性对经典算法进行加速。在神经网络训练过程中,算法利用量子相位估计和Grover搜索算法并行实现相似度计算和标签提取。理论分析表明,本文提出的量子算法相比于经典算法在数据维度上具有指数加速。 展开更多
关键词 量子神经网络 量子相位估计 Grover搜索算法 自组织特征映射
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Intelligent identification method and application of seismic faults based on a balanced classification network
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作者 Yang Jing Ding Ren-Wei +4 位作者 Wang Hui-Yong Lin Nian-Tian Zhao Li-Hong Zhao Shuo Zhang Yu-Jie 《Applied Geophysics》 SCIE CSCD 2022年第2期209-220,307,共13页
This study combined fault identification with a deep learning algorithm and applied a convolutional neural network(CNN)design based on an improved balanced crossentropy(BCE)loss function to address the low accuracy in... This study combined fault identification with a deep learning algorithm and applied a convolutional neural network(CNN)design based on an improved balanced crossentropy(BCE)loss function to address the low accuracy in the intelligent identification of seismic faults and the slow training speed of convolutional neural networks caused by unbalanced training sample sets.The network structure and optimal hyperparameters were determined by extracting feature maps layer by layer and by analyzing the results of seismic feature extraction.The BCE loss function was used to add the parameter which is the ratio of nonfaults to the total sample sets,thereby changing the loss function to find the reference of the minimum weight parameter and adjusting the ratio of fault to nonfault data.The method overcame the unbalanced number of sample sets and improved the iteration speed.After a brief training,the accuracy could reach more than 95%,and gradient descent was evident.The proposed method was applied to fault identification in an oilfield area.The trained model can predict faults clearly,and the prediction results are basically consistent with an actual case,verifying the effectiveness and adaptability of the method. 展开更多
关键词 convolutional neural network seismic fault identification balanced cross-entropy loss function feature map
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一种GOA优化SOM神经网络的VP型倾斜仪故障智能诊断方法 被引量:5
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作者 庞聪 马武刚 +4 位作者 李查玮 龚燕民 刘晓磊 江勇 廖成旺 《大地测量与地球动力学》 CSCD 北大核心 2023年第3期322-326,共5页
提出一种VP型倾斜仪故障智能诊断方法。利用经验模态分解(EMD)将归一化故障信号分解为6个本征模态函数(IMF),分别计算其近似熵,构建EMD多尺度近似熵输入矩阵;结合蝗虫优化算法(GOA)对自组织特征映射(SOM)神经网络的参数进行优化,将得到... 提出一种VP型倾斜仪故障智能诊断方法。利用经验模态分解(EMD)将归一化故障信号分解为6个本征模态函数(IMF),分别计算其近似熵,构建EMD多尺度近似熵输入矩阵;结合蝗虫优化算法(GOA)对自组织特征映射(SOM)神经网络的参数进行优化,将得到的GOA最优值嵌入到SOM模型中,组建GOA-SOM诊断模型。应用诊断测试集得到诊断目标的聚类标签值,将其与训练集的聚类标签以及真实故障类型进行比对,得到故障诊断结果。结果证明,GOA-SOM模型在100次随机抽样条件下的诊断正确率均值和标准差分别为99.329 7%、1.218 8,优于传统诊断模型。 展开更多
关键词 倾斜仪故障诊断 经验模态分解 蝗虫优化算法 自组织特征映射神经网络 多尺度近似熵
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VP型宽频带倾斜仪故障信号的BBA-SOM智能诊断 被引量:2
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作者 马武刚 庞聪 +1 位作者 龚燕民 刘晓磊 《科学技术与工程》 北大核心 2023年第14期6012-6017,共6页
针对现有VP型倾斜仪故障诊断主要依靠人工经验和诊断流程较为复杂的问题,提出以互补集合经验模态分解(complete ensemble empirical mode decomposition,CEEMD)多尺度近似熵和二进制蝙蝠算法(binary bat algorithm,BBA)优化SOM神经网络... 针对现有VP型倾斜仪故障诊断主要依靠人工经验和诊断流程较为复杂的问题,提出以互补集合经验模态分解(complete ensemble empirical mode decomposition,CEEMD)多尺度近似熵和二进制蝙蝠算法(binary bat algorithm,BBA)优化SOM神经网络参数的VP型倾斜仪故障诊断新方。首先,将归一化后的仪器故障信号进行CEEMD分解,对6阶本征模态函数(intrinsic mode function,IMF)求取多尺度近似熵值;然后将网络输入法按比例分为训练集和测试集,以训练集的识别率为适应度函数,应用二进制蝙蝠算法(binary bat algorithm,BBA)优化SOM神经网络的竞争层维数和网络训练次数;最后应用上述得到的BBA-SOM网络模型对倾斜仪故障特征数据进行辨识。实验表明:CEEMD多尺度近似熵判据对倾斜仪故障特征的区分效果符合预期;相对于朴素贝叶斯、AdaBoost集成学习与LDA等学习模型,BBA-SOM模型可以准确进行故障诊断;该方法对实现VP型倾斜仪故障的自动诊断有重要现实意义。 展开更多
关键词 VP宽频带倾斜仪 故障诊断 互补集合经验模态分解 二进制蝙蝠算法 自组织特征映射神经网络
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基于特征映射和联合学习的可解释新闻推荐
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作者 何丽 王京豪 段建勇 《计算机工程与设计》 北大核心 2023年第9期2851-2858,共8页
为解决现有个性化推荐系统大多是黑箱模式,无法提供可靠的推荐理由这一问题,对可解释性推荐进行深入研究。为在消除元数据需求的情况下,实现推荐的可解释性和性能之间权衡,提出一种特征映射方法,将不可解释的一般特征映射到可解释的方... 为解决现有个性化推荐系统大多是黑箱模式,无法提供可靠的推荐理由这一问题,对可解释性推荐进行深入研究。为在消除元数据需求的情况下,实现推荐的可解释性和性能之间权衡,提出一种特征映射方法,将不可解释的一般特征映射到可解释的方面特征,该方面特征可用于解释生成;同时使用一个联合学习模型平衡准确预测和生成解释这两个任务,实现推荐中令人满意的准确性和可解释性。通过在真实数据集上的实验,验证了该方法在推荐准确度和解释语句质量两方面都有所提升。 展开更多
关键词 可解释推荐 联合学习 注意力机制 神经网络 新闻推荐 特征映射 自然语言处理
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基于特征融合的牵引电机轴承声学故障诊断
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作者 杨岗 卫昱乾 李芾 《机车电传动》 北大核心 2023年第2期103-112,共10页
滚动轴承作为高速列车牵引电机的重要部件,其故障情况严重影响列车运行安全。声学轴承故障诊断方式具有无安装侵入性、运维成本低的优点,但也具有信噪比低、故障特征难以提取的缺点,机器学习则具有克服噪声影响的鲁棒性。针对应用机器... 滚动轴承作为高速列车牵引电机的重要部件,其故障情况严重影响列车运行安全。声学轴承故障诊断方式具有无安装侵入性、运维成本低的优点,但也具有信噪比低、故障特征难以提取的缺点,机器学习则具有克服噪声影响的鲁棒性。针对应用机器学习进行声学故障诊断时,少量特征无法全面表征轴承故障的难题,文章提出将格拉姆角场(GAF)与小波时频图进行叠加融合,构成6通道融合特征图用以有效表征轴承的故障。首先,建立牵引电机轴承声学故障试验台获取故障声学信号;其次,建立基于GAF的声学信号融合特征图,然后使用残差网络(ResNET)模型针对融合特征图特征训练并验证故障分类模型,并与以单种特征图作为特征的故障分类方法进行准确率对比。结果表明,基于GAF的融合特征图的声学故障分类模型具有99.89%的准确率,融合特征图能更有效地映射轴承故障。 展开更多
关键词 牵引电机轴承 声学故障诊断 卷积神经网络 融合特征图 格拉姆角场 高速列车
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基于特征图融合的对抗样本生成方法
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作者 张世辉 张晓微 +1 位作者 宋丹丹 路佳琪 《燕山大学学报》 CAS 北大核心 2023年第4期337-346,共10页
为检验现有深度学习算法的鲁棒性和安全性,提出一种基于特征图融合的对抗样本生成方法。首先,分析卷积神经网络在图像分类任务中所提取不同层次特征图的特点,提出利用多层次特征图进行对抗扰动构造的方法思想;其次,引入通道注意力模块... 为检验现有深度学习算法的鲁棒性和安全性,提出一种基于特征图融合的对抗样本生成方法。首先,分析卷积神经网络在图像分类任务中所提取不同层次特征图的特点,提出利用多层次特征图进行对抗扰动构造的方法思想;其次,引入通道注意力模块对卷积层输出特征图进行权重分配,以此代表不同特征图对分类结果的影响程度;再次,构建基础网络用于选取高权重特征图,并对显著特征信息进行像素值修改来生成扰动特征图;最后,将不同扰动特征图融合为对抗扰动,并添加至原始输入样本中生成对抗样本。实验结果表明,所提对抗样本生成方法在CIFAR-10和MNIST数据集上兼顾了攻击成功率和样本视觉感知效果,与现有代表性对抗样本生成方法相比,在高难度的非交互式黑盒模型上取得了较好的攻击效果。 展开更多
关键词 对抗样本 特征图 通道注意力模块 卷积神经网络 图像分类
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基于多传感器融合声纹特征图谱的变压器铁芯松动故障诊断方法 被引量:3
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作者 李楠 马宏忠 +2 位作者 段大卫 朱昊 何萍 《振动与冲击》 EI CSCD 北大核心 2023年第15期129-137,198,共10页
变压器铁芯轻微松动故障给变压器安全稳定运行留下巨大隐患,目前尚缺乏切实可靠的诊断方法。提出一种基于多传感器融合声纹特征图谱的变压器铁芯松动故障诊断方法。首先,利用4个传感器采集声纹时序序列,通过小波变换生成声纹特征图谱,... 变压器铁芯轻微松动故障给变压器安全稳定运行留下巨大隐患,目前尚缺乏切实可靠的诊断方法。提出一种基于多传感器融合声纹特征图谱的变压器铁芯松动故障诊断方法。首先,利用4个传感器采集声纹时序序列,通过小波变换生成声纹特征图谱,利用熵权法确定不同传感器信号的权重分配,将4个声纹特征图谱加权融合,从而形成多传感器融合声纹特征图谱。其次,将融合声纹特征图谱输入优化后的ShuffleNetV2模型,通过分组卷积和通道混洗得到铁芯松动程度。最后,通过现场试验验证了方法的有效性。结果表明,所提方法对25%,50%,75%及100%的松动程度均能实现可靠诊断,平均准确率高达99.6%。与采用傅里叶频谱(fast Fourier transform, FFT)、格拉米角场(Gramian angular field, GAF)、马尔可夫变换场(Markov transform field, MTF)以及混沌特征(recurrence plot, RP)等传统声纹特征图谱的诊断相比,所提方法识别准确率提高了12.2%;与采用单传感器声纹特征图谱的诊断相比,所提方法识别准确度提高了5.8%;与采用AlexNet、MobilleNetV2、GoogleNet以及ResNet等卷积神经网络模型的诊断相比,所提方法识别准确率提高了2.7%。 展开更多
关键词 电力变压器 铁芯松动故障 声纹特征图谱 多传感器融合 卷积神经网络
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