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An Ensemble Detection Method for Shilling Attacks Based on Features of Automatic Extraction 被引量:3
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作者 Yaojun Hao Fuzhi Zhang Jinbo Chao 《China Communications》 SCIE CSCD 2019年第8期130-146,共17页
Faced with the evolving attacks in recommender systems, many detection features have been proposed by human engineering and used in supervised or unsupervised detection methods. However, the detection features extract... Faced with the evolving attacks in recommender systems, many detection features have been proposed by human engineering and used in supervised or unsupervised detection methods. However, the detection features extracted by human engineering are usually aimed at some specific types of attacks. To further detect other new types of attacks, the traditional methods have to re-extract detection features with high knowledge cost. To address these limitations, the method for automatic extraction of robust features is proposed and then an Adaboost-based detection method is presented. Firstly, to obtain robust representation with prior knowledge, unlike uniform corruption rate in traditional mLDA(marginalized Linear Denoising Autoencoder), different corruption rates for items are calculated according to the ratings’ distribution. Secondly, the ratings sparsity is used to weight the mapping matrix to extract low-dimensional representation. Moreover, the uniform corruption rate is also set to the next layer in mSLDA(marginalized Stacked Linear Denoising Autoencoder) to extract the stable and robust user features. Finally, under the robust feature space, an Adaboost-based detection method is proposed to alleviate the imbalanced classification problem. Experimental results on the Netflix and Amazon review datasets indicate that the proposed method can effectively detect various attacks. 展开更多
关键词 shilling ATTACK ENSEMBLE detection featureS of automatic extraction marginalized linear DENOISING autoencoder
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Wake-Up-Word Feature Extraction on FPGA
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作者 Veton ZKepuska Mohamed MEljhani Brian HHight 《World Journal of Engineering and Technology》 2014年第1期1-12,共12页
Wake-Up-Word Speech Recognition task (WUW-SR) is a computationally very demand, particularly the stage of feature extraction which is decoded with corresponding Hidden Markov Models (HMMs) in the back-end stage of the... Wake-Up-Word Speech Recognition task (WUW-SR) is a computationally very demand, particularly the stage of feature extraction which is decoded with corresponding Hidden Markov Models (HMMs) in the back-end stage of the WUW-SR. The state of the art WUW-SR system is based on three different sets of features: Mel-Frequency Cepstral Coefficients (MFCC), Linear Predictive Coding Coefficients (LPC), and Enhanced Mel-Frequency Cepstral Coefficients (ENH_MFCC). In (front-end of Wake-Up-Word Speech Recognition System Design on FPGA) [1], we presented an experimental FPGA design and implementation of a novel architecture of a real-time spectrogram extraction processor that generates MFCC, LPC, and ENH_MFCC spectrograms simultaneously. In this paper, the details of converting the three sets of spectrograms 1) Mel-Frequency Cepstral Coefficients (MFCC), 2) Linear Predictive Coding Coefficients (LPC), and 3) Enhanced Mel-Frequency Cepstral Coefficients (ENH_MFCC) to their equivalent features are presented. In the WUW- SR system, the recognizer’s frontend is located at the terminal which is typically connected over a data network to remote back-end recognition (e.g., server). The WUW-SR is shown in Figure 1. The three sets of speech features are extracted at the front-end. These extracted features are then compressed and transmitted to the server via a dedicated channel, where subsequently they are decoded. 展开更多
关键词 Speech Recognition System feature extraction Mel-Frequency Cepstral Coefficients linear Predictive Coding Coefficients Enhanced Mel-Frequency Cepstral Coefficients Hidden Markov Models Field-Programmable Gate Arrays
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Automated Extraction for Water Bodies Using New Water Index from Landsat 8 OLI Images 被引量:5
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作者 Pu YAN Yue FANG +2 位作者 Jie CHEN Gang WANG Qingwei TANG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期59-75,共17页
The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to... The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to highlight water bodies in remote sensing images.We employ a new water index and digital image processing technology to extract water bodies automatically and accurately from Landsat 8 OLI images.Firstly,we preprocess Landsat 8 OLI images with radiometric calibration and atmospheric correction.Subsequently,we apply KT transformation,LBV transformation,AWEI nsh,and HIS transformation to the preprocessed image to calculate a new water index.Then,we perform linear feature enhancement and improve the local adaptive threshold segmentation method to extract small water bodies accurately.Meanwhile,we employ morphological enhancement and improve the local adaptive threshold segmentation method to extract large water bodies.Finally,we combine small and large water bodies to get complete water bodies.Compared with other traditional methods,our method has apparent advantages in water extraction,particularly in the extraction of small water bodies. 展开更多
关键词 water bodies extraction Landsat 8 OLI images water index improved local adaptive threshold segmentation linear feature enhancement
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Robust Speech Recognition System Using Conventional and Hybrid Features of MFCC,LPCC,PLP,RASTA-PLP and Hidden Markov Model Classifier in Noisy Conditions 被引量:7
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作者 Veton Z.Kepuska Hussien A.Elharati 《Journal of Computer and Communications》 2015年第6期1-9,共9页
In recent years, the accuracy of speech recognition (SR) has been one of the most active areas of research. Despite that SR systems are working reasonably well in quiet conditions, they still suffer severe performance... In recent years, the accuracy of speech recognition (SR) has been one of the most active areas of research. Despite that SR systems are working reasonably well in quiet conditions, they still suffer severe performance degradation in noisy conditions or distorted channels. It is necessary to search for more robust feature extraction methods to gain better performance in adverse conditions. This paper investigates the performance of conventional and new hybrid speech feature extraction algorithms of Mel Frequency Cepstrum Coefficient (MFCC), Linear Prediction Coding Coefficient (LPCC), perceptual linear production (PLP), and RASTA-PLP in noisy conditions through using multivariate Hidden Markov Model (HMM) classifier. The behavior of the proposal system is evaluated using TIDIGIT human voice dataset corpora, recorded from 208 different adult speakers in both training and testing process. The theoretical basis for speech processing and classifier procedures were presented, and the recognition results were obtained based on word recognition rate. 展开更多
关键词 Speech Recognition Noisy Conditions feature extraction Mel-Frequency Cepstral Coefficients linear Predictive Coding Coefficients Perceptual linear Production RASTA-PLP Isolated Speech Hidden Markov Model
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Direct linear discriminant analysis based on column pivoting QR decomposition and economic SVD
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作者 胡长晖 路小波 +1 位作者 杜一君 陈伍军 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期395-399,共5页
A direct linear discriminant analysis algorithm based on economic singular value decomposition (DLDA/ESVD) is proposed to address the computationally complex problem of the conventional DLDA algorithm, which directl... A direct linear discriminant analysis algorithm based on economic singular value decomposition (DLDA/ESVD) is proposed to address the computationally complex problem of the conventional DLDA algorithm, which directly uses ESVD to reduce dimension and extract eigenvectors corresponding to nonzero eigenvalues. Then a DLDA algorithm based on column pivoting orthogonal triangular (QR) decomposition and ESVD (DLDA/QR-ESVD) is proposed to improve the performance of the DLDA/ESVD algorithm by processing a high-dimensional low rank matrix, which uses column pivoting QR decomposition to reduce dimension and ESVD to extract eigenvectors corresponding to nonzero eigenvalues. The experimental results on ORL, FERET and YALE face databases show that the proposed two algorithms can achieve almost the same performance and outperform the conventional DLDA algorithm in terms of computational complexity and training time. In addition, the experimental results on random data matrices show that the DLDA/QR-ESVD algorithm achieves better performance than the DLDA/ESVD algorithm by processing high-dimensional low rank matrices. 展开更多
关键词 direct linear discriminant analysis column pivoting orthogonal triangular decomposition economic singular value decomposition dimension reduction feature extraction
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Facial Feature Extraction Method Based on Coefficients of Variances 被引量:1
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作者 宋枫溪 张大鹏 +1 位作者 陈才扣 杨静宇 《Journal of Computer Science & Technology》 SCIE EI CSCD 2007年第4期626-632,共7页
Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) are two popular feature extraction techniques in statistical pattern recognition field. Due to small sample size problem LDA cannot be dire... Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) are two popular feature extraction techniques in statistical pattern recognition field. Due to small sample size problem LDA cannot be directly applied to appearance-based face recognition tasks. As a consequence, a lot of LDA-based facial feature extraction techniques are proposed to deal with the problem one after the other. Nullspace Method is one of the most effective methods among them. The Nullspace Method tries to find a set of discriminant vectors which maximize the between-class scatter in the null space of the within-class scatter matrix. The calculation of its discriminant vectors will involve performing singular value decomposition on a high-dimensional matrix. It is generally memory- and time-consuming. Borrowing the key idea in Nullspace method and the concept of coefficient of variance in statistical analysis we present a novel facial feature extraction method, i.e., Discriminant based on Coefficient of Variance (DCV) in this paper. Experimental results performed on the FERET and AR face image databases demonstrate that DCV is a promising technique in comparison with Eigenfaces, Nullspace Method, and other state-of-the-art facial feature extraction methods. 展开更多
关键词 coefficient of variation face recognition null space Gram-Schmidt orthogonalizing procedure linear feature extraction
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Balanced multiple weighted linear discriminant analysis and its application to visual process monitoring 被引量:1
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作者 Weipeng Lu Xuefeng Yan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第8期128-137,共10页
Visual process monitoring is important in complex chemical processes.To address the high state separation of industrial data,we propose a new criterion for feature extraction called balanced multiple weighted linear d... Visual process monitoring is important in complex chemical processes.To address the high state separation of industrial data,we propose a new criterion for feature extraction called balanced multiple weighted linear discriminant analysis(BMWLDA).Then,we combine BMWLDA with self-organizing map(SOM)for visual monitoring of industrial operation processes.BMWLDA can extract the discriminative feature vectors from the original industrial data and maximally separate industrial operation states in the space spanned by these discriminative feature vectors.When the discriminative feature vectors are used as the input to SOM,the training result of SOM can differentiate industrial operation states clearly.This function improves the performance of visual monitoring.Continuous stirred tank reactor is used to verify that the class separation performance of BMWLDA is more effective than that of traditional linear discriminant analysis,approximate pairwise accuracy criterion,max–min distance analysis,maximum margin criterion,and local Fisher discriminant analysis.In addition,the method that combines BMWLDA with SOM can effectively perform visual process monitoring in real time. 展开更多
关键词 linear discriminant analysis Process monitoring Self-organizing map feature extraction Continuous stirred tank reactor process
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Pattern Analysis and Regressive Linear Measure for Botnet Detection
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作者 B.Padmavathi B.Muthukumar 《Computer Systems Science & Engineering》 SCIE EI 2022年第10期119-139,共21页
Capturing the distributed platform with remotely controlled compromised machines using botnet is extensively analyzed by various researchers.However,certain limitations need to be addressed efficiently.The provisionin... Capturing the distributed platform with remotely controlled compromised machines using botnet is extensively analyzed by various researchers.However,certain limitations need to be addressed efficiently.The provisioning of detection mechanism with learning approaches provides a better solution more broadly by saluting multi-objective constraints.The bots’patterns or features over the network have to be analyzed in both linear and non-linear manner.The linear and non-linear features are composed of high-level and low-level features.The collected features are maintained over the Bag of Features(BoF)where the most influencing features are collected and provided into the classifier model.Here,the linearity and non-linearity of the threat are evaluated with Support Vector Machine(SVM).Next,with the collected BoF,the redundant features are eliminated as it triggers overhead towards the predictor model.Finally,a novel Incoming data Redundancy Elimination-based learning model(RedE-L)is built to classify the network features to provide robustness towards BotNets detection.The simulation is carried out in MATLAB environment,and the evaluation of proposed RedE-L model is performed with various online accessible network traffic dataset(benchmark dataset).The proposed model intends to show better tradeoff compared to the existing approaches like conventional SVM,C4.5,RepTree and so on.Here,various metrics like Accuracy,detection rate,Mathews Correlation Coefficient(MCC),and some other statistical analysis are performed to show the proposed RedE-L model's reliability.The F1-measure is 99.98%,precision is 99.93%,Accuracy is 99.84%,TPR is 99.92%,TNR is 99.94%,FNR is 0.06 and FPR is 0.06 respectively. 展开更多
关键词 BOTNET threat intrusion features linearity and non-linearity redundancy regressive linear measure classification redundancy eliminationbased learning model
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Linear Dimension Reduction for Multiple Heteroscedastic Multivariate Normal Populations
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作者 Songthip T. Ounpraseuth Phil D. Young +2 位作者 Johanna S. van Zyl Tyler W. Nelson Dean M. Young 《Open Journal of Statistics》 2015年第4期311-333,共23页
For the case where all multivariate normal parameters are known, we derive a new linear dimension reduction (LDR) method to determine a low-dimensional subspace that preserves or nearly preserves the original feature-... For the case where all multivariate normal parameters are known, we derive a new linear dimension reduction (LDR) method to determine a low-dimensional subspace that preserves or nearly preserves the original feature-space separation of the individual populations and the Bayes probability of misclassification. We also give necessary and sufficient conditions which provide the smallest reduced dimension that essentially retains the Bayes probability of misclassification from the original full-dimensional space in the reduced space. Moreover, our new LDR procedure requires no computationally expensive optimization procedure. Finally, for the case where parameters are unknown, we devise a LDR method based on our new theorem and compare our LDR method with three competing LDR methods using Monte Carlo simulations and a parametric bootstrap based on real data. 展开更多
关键词 linear TRANSFORMATION BAYES Classification feature extraction PROBABILITY of MISCLASSIFICATION
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A Highly Accurate Dysphonia Detection System Using Linear Discriminant Analysis
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作者 Anas Basalamah Mahedi Hasan +1 位作者 Shovan Bhowmik Shaikh Akib Shahriyar 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期1921-1938,共18页
The recognition of pathological voice is considered a difficult task for speech analysis.Moreover,otolaryngologists needed to rely on oral communication with patients to discover traces of voice pathologies like dysph... The recognition of pathological voice is considered a difficult task for speech analysis.Moreover,otolaryngologists needed to rely on oral communication with patients to discover traces of voice pathologies like dysphonia that are caused by voice alteration of vocal folds and their accuracy is between 60%–70%.To enhance detection accuracy and reduce processing speed of dysphonia detection,a novel approach is proposed in this paper.We have leveraged Linear Discriminant Analysis(LDA)to train multiple Machine Learning(ML)models for dysphonia detection.Several ML models are utilized like Support Vector Machine(SVM),Logistic Regression,and K-nearest neighbor(K-NN)to predict the voice pathologies based on features like Mel-Frequency Cepstral Coefficients(MFCC),Fundamental Frequency(F0),Shimmer(%),Jitter(%),and Harmonic to Noise Ratio(HNR).The experiments were performed using Saarbrucken Voice Data-base(SVD)and a privately collected dataset.The K-fold cross-validation approach was incorporated to increase the robustness and stability of the ML models.According to the experimental results,our proposed approach has a 70%increase in processing speed over Principal Component Analysis(PCA)and performs remarkably well with a recognition accuracy of 95.24%on the SVD dataset surpassing the previous best accuracy of 82.37%.In the case of the private dataset,our proposed method achieved an accuracy rate of 93.37%.It can be an effective non-invasive method to detect dysphonia. 展开更多
关键词 Dimensionality reduction dysphonia detection linear discriminant analysis logistic regression speech feature extraction support vector machine
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Nonlinearly correlated failure analysis and autonomic prediction for distributed systems
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作者 Lu Xu Wang Huiqiang +2 位作者 Lv Xiao Feng Guangsheng Zhou Renjie 《High Technology Letters》 EI CAS 2011年第3期290-298,共9页
In order to achieve failure prediction without manual intervention for distributed systems, a novel failure feature analysis and extraction approach to automate failure prediction is proposed. Compared with the tradit... In order to achieve failure prediction without manual intervention for distributed systems, a novel failure feature analysis and extraction approach to automate failure prediction is proposed. Compared with the traditional methods which focus on building heuristic rules or models, the autonomic prediction approach analyzes the nonlinear correlation of failure features by recognizing failure patterns. Failure data are sorted according to the nonlinear correlation and failure signature is proposed for autonomic prediction. In addition, the Manifold Learning algorithm named supervised locally linear embedding is applied to achieve feature extraction. Based on the runtime monitoring of failure metrics, the experimental results indicate that the proposed method has better performance in terms of both correlation recognition precision and feature extraction quality and thus it can be used to design efficient autonomic failure prediction for distributed systems. 展开更多
关键词 failure prediction nonlinear correlation analysis feature extraction locally linear embedding autonomic computing
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Kernel feature extraction methods observed from the viewpoint of generating-kernels
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作者 Jian YANG 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2011年第1期43-55,共13页
This paper introduces an idea of generating a kernel from an arbitrary function by embedding the training samples into the function.Based on this idea,we present two nonlinear feature extraction methods:generating ker... This paper introduces an idea of generating a kernel from an arbitrary function by embedding the training samples into the function.Based on this idea,we present two nonlinear feature extraction methods:generating kernel principal component analysis(GKPCA)and generating kernel Fisher discriminant(GKFD).These two methods are shown to be equivalent to the function-mapping-space PCA(FMS-PCA)and the function-mapping-space linear discriminant analysis(FMS-LDA)methods,respectively.This equivalence reveals that the generating kernel is actually determined by the corresponding function map.From the generating kernel point of view,we can classify the current kernel Fisher discriminant(KFD)algorithms into two categories:KPCA+LDA based algorithms and straightforward KFD(SKFD)algorithms.The KPCA+LDA based algorithms directly work on the given kernel and are not suitable for non-kernel functions,while the SKFD algorithms essentially work on the generating kernel from a given symmetric function and are therefore suitable for non-kernels as well as kernels.Finally,we outline the tensor-based feature extraction methods and discuss ways of extending tensor-based methods to their generating kernel versions. 展开更多
关键词 kernel methods feature extraction principal component analysis(PCA) Fisher linear discriminant analysis(FLD or LDA) tensor-based methods
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基于改进Steger算法的Ⅴ型焊缝识别方法 被引量:1
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作者 郭北涛 刘磊 +2 位作者 张丽秀 刘瀚齐 金福鑫 《组合机床与自动化加工技术》 北大核心 2025年第3期182-186,共5页
针对采用线结构光进行Ⅴ型焊缝特征识别时准确性不足和效率低的问题,提出了一种基于改进Steger算法的Ⅴ型焊缝识别方法。通过改进Steger算法流程和自适应感兴趣区域的选择,提升了Ⅴ型焊缝特征点提取精度和效率。首先,通过对焊缝图像进... 针对采用线结构光进行Ⅴ型焊缝特征识别时准确性不足和效率低的问题,提出了一种基于改进Steger算法的Ⅴ型焊缝识别方法。通过改进Steger算法流程和自适应感兴趣区域的选择,提升了Ⅴ型焊缝特征点提取精度和效率。首先,通过对焊缝图像进行平滑处理和阈值分割操作,将结构光条纹与背景信息分离;其次,采用一种新的感兴趣区域选择方法,有效地找出了结构光条纹所在区域;然后,采用骨架细化法和Canny边缘检测算法估算出光条纹宽度,根据宽度信息分割光条纹求取光条中心线;最后,采用最小二乘法得到Ⅴ型焊缝特征点的亚像素坐标。实验结果表明,改进Steger算法运行速度提升约60%,平均均方根误差降低0.23 pixels,提高了Steger算法的速度和精度。Ⅴ型焊缝识别误差均小于1.0 mm,证明了该方法能够准确地识别出Ⅴ型焊缝特征,满足实际焊接精度要求。 展开更多
关键词 线结构光 Steger 感兴趣区域 直线拟合 特征提取
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一种自适应残差卷积自编码网络及其故障诊断应用
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作者 潘天成 陈龙 +1 位作者 蒲春雷 陈志强 《机电工程》 北大核心 2025年第3期529-538,共10页
针对传统卷积自编码器(CAE)会将不同故障产生的相似信号进行相同的非线性变换,导致故障诊断准确率下降的问题,提出了一种自适应残差卷积自编码网络(ARCAE),并将其应用于滚动轴承故障诊断中。首先,在残差模块的基础上,引入了自适应参数... 针对传统卷积自编码器(CAE)会将不同故障产生的相似信号进行相同的非线性变换,导致故障诊断准确率下降的问题,提出了一种自适应残差卷积自编码网络(ARCAE),并将其应用于滚动轴承故障诊断中。首先,在残差模块的基础上,引入了自适应参数化修正线性单元(APReLU),建立了自适应残差模块(ARM),ARM可以对相似的输入特征进行自适应非线性变换,避免了特征的错误识别;其次,在CAE中嵌入多级ARM,构建了ARCAE,增加了CAE的深度,提取了更具鉴别性的深层次特征,同时有效防止了网络加深而造成的性能退化;最后,基于ARCAE建立了针对一维信号的故障诊断新方法,将其应用于无监督滚动轴承故障诊断中,并通过两个不同类型的实验,对上述方法的有效性进行了验证。研究结果表明:在恒定转速工况下,ARCAE的诊断准确率最高,平均准确率达到了97.05%,且标准差仅为0.007,远低于其他几种传统CAE网络;在变转速工况下,ARCAE模型诊断准确率仍然是最高的,平均准确率达到了93.25%,由此说明ARCAE具有较高的特征提取能力和分类准确率;此外,变转速工况下,由于转速变化导致不同状态的振动信号特征差异变大,诊断难度加大,但与其他几种传统CAE网络相比,ARCAE诊断准确率下降最少,仅为5.37%,说明ARCAE具有更强的鲁棒性和稳定性。 展开更多
关键词 滚动轴承 自适应残差卷积自编码网络 自适应参数化修正线性单元 自适应残差模块 无监督故障诊断 特征提取
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基于概率模型与信息熵的局部线性嵌入算法
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作者 刘远红 毋毓斌 《计算机科学》 北大核心 2025年第S1期643-650,共8页
局部线性嵌入算法采用欧氏距离选择邻域点,这通常会损失数据集本身的非线性特征,造成邻域点选取错误,且仅使用欧氏距离构造权重会导致信息挖掘不充分。针对以上问题,提出基于概率模型与信息熵的局部线性嵌入算法(Probability informatio... 局部线性嵌入算法采用欧氏距离选择邻域点,这通常会损失数据集本身的非线性特征,造成邻域点选取错误,且仅使用欧氏距离构造权重会导致信息挖掘不充分。针对以上问题,提出基于概率模型与信息熵的局部线性嵌入算法(Probability information entropy-LLE,PIE-LLE)。首先,为了使邻域点选择更加合理,从数据集的概率分布角度出发,考虑样本点及其邻域的概率分布,为样本点构造符合局部分布的邻域集合。其次,为了充分提取样本的局部结构信息,在权重构造阶段,分别计算样本所属邻域概率以及每个样本的信息熵,融合二者信息重构低维样本。最后,在两个轴承故障数据集上的实验表明,所提方法故障识别准确度最高达到了100%,高于其他对比算法;在邻域点个数5~15范围内,PIE-LLE算法展现出良好的低维可视化效果;在参数敏感性实验中,该算法可以保持Fisher指标较大,有效提高了算法的分类准确度和稳定性。 展开更多
关键词 局部线性嵌入算法 概率模型 信息熵 特征提取 故障诊断
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一种改进的Yolov5s煤矿井下人员计数模型
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作者 井晶 高宇蒙 +1 位作者 赵作鹏 闵冰冰 《计算机仿真》 2025年第4期525-530,551,共7页
实现井下人数实时统计对实现井下限员生产具有重要意义。现有人员计数算法对普通环境中稀疏人群的计数效果良好,但对复杂的井下环境中密集人群的计数效果不佳。针对上述问题,提出了结合Yolov5s和线性回归的人员计数模型:Yolov5s-LR。首... 实现井下人数实时统计对实现井下限员生产具有重要意义。现有人员计数算法对普通环境中稀疏人群的计数效果良好,但对复杂的井下环境中密集人群的计数效果不佳。针对上述问题,提出了结合Yolov5s和线性回归的人员计数模型:Yolov5s-LR。首先,根据注意力机制动态地调整每个卷积核的权重,从而提高模型在井下昏暗密集环境中的特征提取能力;其次,使用与检测头共享骨干网络的线性回归计数头预测人数,并通过L2损失函数进行模型训练,从而实现误差较低的人员计数。实验结果表明,在自建的煤矿井下人员计数数据集上,上述模型的人员检测精度比Yolov5s高3.1%,人员计数的MAE和MSE比当前流行的人员计数模型中效果最好的DKCNN-LR模型降低了0.3和0.58。 展开更多
关键词 人员计数 计算机视觉 线性回归 动态核 特征提取
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基于Gabor滤波器和改进线性判别分析的掌纹识别方法
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作者 马思远 江粼 +2 位作者 李春林 胡钦太 武继刚 《计算机工程》 北大核心 2025年第6期320-326,共7页
现有的基于方向模式的掌纹识别方法利用预定义的滤波器来获取掌纹图像中的线响应,然而,这种方法对丰富的先验知识依赖较强,且常常忽略重要的方向信息,还会造成维度过大的问题。为了解决以上问题,提出一种基于Gabor滤波器和改进线性判别... 现有的基于方向模式的掌纹识别方法利用预定义的滤波器来获取掌纹图像中的线响应,然而,这种方法对丰富的先验知识依赖较强,且常常忽略重要的方向信息,还会造成维度过大的问题。为了解决以上问题,提出一种基于Gabor滤波器和改进线性判别分析的掌纹识别方法。首先使用二维Gabor滤波器提取掌纹图像中的鲁棒卷积差分特征,提取到的特征可以更充分地描述掌纹图像中每个像素的局部方向的变化。然后提出一种判别特征学习模型,该模型通过最大化类间距离和最小化类内距离,从局部方向特征中学习出判别特征,在降低数据维度的同时减少噪声的影响。在PolyU、M_Blue、GPDS和IITD 4个公共掌纹数据库上进行实验,其中在GPDS和IITD 2个非接触式掌纹数据库上的识别率分别达到96.80%和99.29%。实验结果表明,提出的算法能够更有效地提取掌纹图像的判别特征,并显著提高掌纹识别的准确度。 展开更多
关键词 掌纹识别 特征选择 特征提取 线性判别分析 方向模式学习
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结合小波变换和高光谱影像的壁画线条增强方法研究
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作者 段鲁楠 张爱武 +2 位作者 陈云生 高峰 郭巨文 《光谱学与光谱分析》 北大核心 2025年第9期2676-2683,共8页
由于年代久远,古代壁画往往画面模糊、线条丢失,难以辨别,而高光谱成像技术可以捕捉目标物质和能量的微变化,有利于增强壁画模糊或丢失的细节信息。因此,利用成像高光谱数据,提出了一种结合小波变换的壁画线条信息增强方法。首先,运用... 由于年代久远,古代壁画往往画面模糊、线条丢失,难以辨别,而高光谱成像技术可以捕捉目标物质和能量的微变化,有利于增强壁画模糊或丢失的细节信息。因此,利用成像高光谱数据,提出了一种结合小波变换的壁画线条信息增强方法。首先,运用分段最小噪声分离(MNF)变换,用最大平均梯度法选择最优MNF波段影像,提取纯净端元,通过全约束最小二乘光谱解混反演对应丰度图,选择线条丰度图与最优MNF波段影像进行波段运算,获得线条增强影像。然后,用MNF逆变换后的影像合成真彩色影像,将线条增强影像与真彩色影像通过高斯滤波增强细节信息,分别进行Haar小波分解,并将两者对应的高频信息融合,保留真彩色影像分解的低频信息,重构得到线条增强的彩色影像。实验表明:通过山西义居寺壁画进行验证,与主成分分析线条特征增强方法对比,该方法平均梯度和边缘强度分别增加0.083 7和15.253 1,具有更好的线条特征增强效果,为后续壁画的保护修复提供帮助。 展开更多
关键词 成像高光谱 端元提取 小波变换 图像融合 线状特征增强
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一种组合特征抽取的新方法 被引量:25
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作者 杨健 杨静宇 +1 位作者 王正群 郭丽 《计算机学报》 EI CSCD 北大核心 2002年第6期570-575,共6页
该文提出了一种基于特征级融合的特征抽取新方法 .首先 ,给出了一种合理的特征融合策略 ,即利用复向量给出组合特征的表示 ,将特征空间从实向量空间拓广到复向量空间 .然后 ,发展了具有统计不相关性的鉴别分析的理论 ,并将其用于复向量... 该文提出了一种基于特征级融合的特征抽取新方法 .首先 ,给出了一种合理的特征融合策略 ,即利用复向量给出组合特征的表示 ,将特征空间从实向量空间拓广到复向量空间 .然后 ,发展了具有统计不相关性的鉴别分析的理论 ,并将其用于复向量空间内最优鉴别特征的抽取 .最后 ,在 Concordia大学的 CENPARMI手写体阿拉伯数字数据库以及南京理工大学 NUST6 0 3HW手写汉字库上的试验结果表明 ,所提出的组合特征抽取方法不仅具有很强的维数压缩能力 。 展开更多
关键词 组合特征抽取 特征融合 线性鉴别分析 手写体字符识别 计算机
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模块二维主成分分析——人脸识别新方法 被引量:10
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作者 陈伏兵 陈秀宏 +1 位作者 张生亮 杨静宇 《计算机工程》 EI CAS CSCD 北大核心 2006年第14期179-180,183,共3页
提出了模块二维主成分分析(M2DPCA)线性鉴别分析方法。M2DPCA方法先对图像矩阵进行分块,对分块得到的子图像矩阵直接进行鉴别分析。其特点是:能有效地降低模式原始特征的维数;可以完全避免使用矩阵的奇异值分解,特征抽取方便;此外,2D... 提出了模块二维主成分分析(M2DPCA)线性鉴别分析方法。M2DPCA方法先对图像矩阵进行分块,对分块得到的子图像矩阵直接进行鉴别分析。其特点是:能有效地降低模式原始特征的维数;可以完全避免使用矩阵的奇异值分解,特征抽取方便;此外,2DPCA是M2DPCA的特例。在ORL人脸库上试验结果表明,M2DPCA方法在识别性能上优于PCA,比2DPCA更具有鲁棒性。 展开更多
关键词 线性鉴别分析 特征抽取 特征矩阵 人脸识别
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