期刊文献+
共找到1,192篇文章
< 1 2 60 >
每页显示 20 50 100
Kernel principal component analysis network for image classification 被引量:5
1
作者 吴丹 伍家松 +3 位作者 曾瑞 姜龙玉 Lotfi Senhadji 舒华忠 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期469-473,共5页
In order to classify nonlinear features with a linear classifier and improve the classification accuracy, a deep learning network named kernel principal component analysis network( KPCANet) is proposed. First, the d... In order to classify nonlinear features with a linear classifier and improve the classification accuracy, a deep learning network named kernel principal component analysis network( KPCANet) is proposed. First, the data is mapped into a higher-dimensional space with kernel principal component analysis to make the data linearly separable. Then a two-layer KPCANet is built to obtain the principal components of the image. Finally, the principal components are classified with a linear classifier. Experimental results showthat the proposed KPCANet is effective in face recognition, object recognition and handwritten digit recognition. It also outperforms principal component analysis network( PCANet) generally. Besides, KPCANet is invariant to illumination and stable to occlusion and slight deformation. 展开更多
关键词 deep learning kernel principal component analysis net(KPCANet) principal component analysis net(PCANet) face recognition object recognition handwritten digit recognition
在线阅读 下载PDF
NONLINEAR DATA RECONCILIATION METHOD BASED ON KERNEL PRINCIPAL COMPONENT ANALYSIS 被引量:6
2
作者 Yan Weiwu Shao HuiheDepartment of Automation,Shanghai Jiaotong University,Shanghai 200030, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第2期117-119,共3页
In the industrial process situation, principal component analysis (PCA) is ageneral method in data reconciliation. However, PCA sometime is unfeasible to nonlinear featureanalysis and limited in application to nonline... In the industrial process situation, principal component analysis (PCA) is ageneral method in data reconciliation. However, PCA sometime is unfeasible to nonlinear featureanalysis and limited in application to nonlinear industrial process. Kernel PCA (KPCA) is extensionof PCA and can be used for nonlinear feature analysis. A nonlinear data reconciliation method basedon KPCA is proposed. The basic idea of this method is that firstly original data are mapped to highdimensional feature space by nonlinear function, and PCA is implemented in the feature space. Thennonlinear feature analysis is implemented and data are reconstructed by using the kernel. The datareconciliation method based on KPCA is applied to ternary distillation column. Simulation resultsshow that this method can filter the noise in measurements of nonlinear process and reconciliateddata can represent the true information of nonlinear process. 展开更多
关键词 principal component analysis kernel data reconciliation NONLINEAR
在线阅读 下载PDF
Robust Recommendation Algorithm Based on Kernel Principal Component Analysis and Fuzzy C-means Clustering 被引量:2
3
作者 YI Huawei NIU Zaiseng +2 位作者 ZHANG Fuzhi LI Xiaohui WANG Yajun 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2018年第2期111-119,共9页
The existing recommendation algorithms have lower robustness in facing of shilling attacks. Considering this problem, we present a robust recommendation algorithm based on kernel principal component analysis and fuzzy... The existing recommendation algorithms have lower robustness in facing of shilling attacks. Considering this problem, we present a robust recommendation algorithm based on kernel principal component analysis and fuzzy c-means clustering. Firstly, we use kernel principal component analysis method to reduce the dimensionality of the original rating matrix, which can extract the effective features of users and items. Then, according to the dimension-reduced rating matrix and the high correlation characteristic between attack profiles, we use fuzzy c-means clustering method to cluster user profiles, which can realize the effective separation of genuine profiles and attack profiles. Finally, we construct an indicator function based on the attack detection results to decrease the influence of attack profiles on the recommendation, and incorporate it into the matrix factorization technology to design the corresponding robust recommendation algorithm. Experiment results indicate that the proposed algorithm is superior to the existing methods in both recommendation accuracy and robustness. 展开更多
关键词 robust recommendation shilling attacks matrixfactorization kernel principal component analysis fuzzy c-meansclustering
原文传递
Decentralized Fault Diagnosis of Large-scale Processes Using Multiblock Kernel Principal Component Analysis 被引量:23
4
作者 ZHANG Ying-Wei ZHOU Hong QIN S. Joe 《自动化学报》 EI CSCD 北大核心 2010年第4期593-597,共5页
关键词 分散系统 MBKPCA SPF PCA
在线阅读 下载PDF
Kernel Generalization of Multi-Rate Probabilistic Principal Component Analysis for Fault Detection in Nonlinear Process 被引量:3
5
作者 Donglei Zheng Le Zhou Zhihuan Song 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第8期1465-1476,共12页
In practical process industries,a variety of online and offline sensors and measuring instruments have been used for process control and monitoring purposes,which indicates that the measurements coming from different ... In practical process industries,a variety of online and offline sensors and measuring instruments have been used for process control and monitoring purposes,which indicates that the measurements coming from different sources are collected at different sampling rates.To build a complete process monitoring strategy,all these multi-rate measurements should be considered for data-based modeling and monitoring.In this paper,a novel kernel multi-rate probabilistic principal component analysis(K-MPPCA)model is proposed to extract the nonlinear correlations among different sampling rates.In the proposed model,the model parameters are calibrated using the kernel trick and the expectation-maximum(EM)algorithm.Also,the corresponding fault detection methods based on the nonlinear features are developed.Finally,a simulated nonlinear case and an actual pre-decarburization unit in the ammonia synthesis process are tested to demonstrate the efficiency of the proposed method. 展开更多
关键词 Fault detection kernel method multi-rate process probability principal component analysis(PPCA)
在线阅读 下载PDF
FUZZY PRINCIPAL COMPONENT ANALYSIS AND ITS KERNEL-BASED MODEL 被引量:4
6
作者 Wu Xiaohong Zhou Jianjiang 《Journal of Electronics(China)》 2007年第6期772-775,共4页
Principal Component Analysis(PCA)is one of the most important feature extraction methods,and Kernel Principal Component Analysis(KPCA)is a nonlinear extension of PCA based on kernel methods.In real world,each input da... Principal Component Analysis(PCA)is one of the most important feature extraction methods,and Kernel Principal Component Analysis(KPCA)is a nonlinear extension of PCA based on kernel methods.In real world,each input data may not be fully assigned to one class and it may partially belong to other classes.Based on the theory of fuzzy sets,this paper presents Fuzzy Principal Component Analysis(FPCA)and its nonlinear extension model,i.e.,Kernel-based Fuzzy Principal Component Analysis(KFPCA).The experimental results indicate that the proposed algorithms have good performances. 展开更多
关键词 principal component analysis (PCA) kernel methods Fuzzy PCA (FPCA) kernel PCA (KPCA)
在线阅读 下载PDF
Application of Particle Swarm Optimization to Fault Condition Recognition Based on Kernel Principal Component Analysis 被引量:1
7
作者 WEI Xiu-ye PAN Hong-xia HUANG Jin-ying WANG Fu-jie 《International Journal of Plant Engineering and Management》 2009年第3期129-135,共7页
Panicle swarm optimization (PSO) is an optimization algorithm based on the swarm intelligent principle. In this paper the modified PSO is applied to a kernel principal component analysis ( KPCA ) for an optimal ke... Panicle swarm optimization (PSO) is an optimization algorithm based on the swarm intelligent principle. In this paper the modified PSO is applied to a kernel principal component analysis ( KPCA ) for an optimal kernel function parameter. We first comprehensively considered within-class scatter and between-class scatter of the sample features. Then, the fitness function of an optimized kernel function parameter is constructed, and the particle swarm optimization algorithm with adaptive acceleration (CPSO) is applied to optimizing it. It is used for gearbox condi- tion recognition, and the result is compared with the recognized results based on principal component analysis (PCA). The results show that KPCA optimized by CPSO can effectively recognize fault conditions of the gearbox by reducing bind set-up of the kernel function parameter, and its results of fault recognition outperform those of PCA. We draw the conclusion that KPCA based on CPSO has an advantage in nonlinear feature extraction of mechanical failure, and is helpful for fault condition recognition of complicated machines. 展开更多
关键词 particle swarm optimization kernel principal component analysis kernel function parameter feature extraction gearbox condition recognition
在线阅读 下载PDF
Application of XGBoost and kernel principal component analysis to forecast oxygen content in ESR
8
作者 Yu-xiao Liu Yan-wu Dong +2 位作者 Zhou-hua Jiang Qi Wang Yu-shuo Li 《Journal of Iron and Steel Research International》 CSCD 2024年第12期2940-2952,共13页
A model combining kernel principal component analysis(KPCA)and Xtreme Gradient Boosting(XGBoost)was introduced for forecasting the final oxygen content of electroslag remelting.KPCA was employed to reduce the dimensio... A model combining kernel principal component analysis(KPCA)and Xtreme Gradient Boosting(XGBoost)was introduced for forecasting the final oxygen content of electroslag remelting.KPCA was employed to reduce the dimensionality of the factors influencing the endpoint oxygen content and to eliminate any existing correlations among these factors.The resulting principal components were then utilized as input variables for the XGBoost prediction model.The KPCA-XGBoost model was trained and proven using data obtained from companies.The model structure was adapted,and hyperparameters were optimized using grid search cross-validation.The model performance of the KPCA-XGBoost model is compared with five machine learning models,including the support vector regression model.The findings demonstrated that the KPCA-XGBoost model exhibited the highest level of prediction accuracy,indicating that the incorporation of KPCA significantly enhanced the regression prediction performance of the model.The accuracy of the KPCA-XGBoost model was 82.4%,97.1%,and 100%at errors of±1.5×10^(-6),±2.0×10^(-6),and±3×10^(-6)for oxygen content,respectively. 展开更多
关键词 Electroslag remelting Oxygen content Machine learning kernel principal component analysis XGBoost
原文传递
Statistical Monitoring of Chemical Processes Based on Sensitive Kernel Principal Components 被引量:9
9
作者 JIANG Qingchao YAN Xuefeng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第6期633-643,共11页
The kernel principal component analysis (KPCA) method employs the first several kernel principal components (KPCs), which indicate the most variance information of normal observations for process monitoring, but m... The kernel principal component analysis (KPCA) method employs the first several kernel principal components (KPCs), which indicate the most variance information of normal observations for process monitoring, but may not reflect the fault information. In this study, sensitive kernel principal component analysis (SKPCA) is proposed to improve process monitoring performance, i.e., to deal with the discordance of T2 statistic and squared prediction error SVE statistic and reduce missed detection rates. T2 statistic can be used to measure the variation di rectly along each KPC and analyze the detection performance as well as capture the most useful information in a process. With the calculation of the change rate of T2 statistic along each KPC, SKPCA selects the sensitive kernel principal components for process monitoring. A simulated simple system and Tennessee Eastman process are employed to demonstrate the efficiency of SKPCA on online monitoring. The results indicate that the monitoring performance is improved significantly. 展开更多
关键词 statistical process monitoring kernel principal component analysis sensitive kernel principal compo-nent Tennessee Eastman process
在线阅读 下载PDF
Comparison of Kernel Entropy Component Analysis with Several Dimensionality Reduction Methods
10
作者 马西沛 张蕾 孙以泽 《Journal of Donghua University(English Edition)》 EI CAS 2017年第4期577-582,共6页
Dimensionality reduction techniques play an important role in data mining. Kernel entropy component analysis( KECA) is a newly developed method for data transformation and dimensionality reduction. This paper conducte... Dimensionality reduction techniques play an important role in data mining. Kernel entropy component analysis( KECA) is a newly developed method for data transformation and dimensionality reduction. This paper conducted a comparative study of KECA with other five dimensionality reduction methods,principal component analysis( PCA),kernel PCA( KPCA),locally linear embedding( LLE),laplacian eigenmaps( LAE) and diffusion maps( DM). Three quality assessment criteria, local continuity meta-criterion( LCMC),trustworthiness and continuity measure(T&C),and mean relative rank error( MRRE) are applied as direct performance indexes to assess those dimensionality reduction methods. Moreover,the clustering accuracy is used as an indirect performance index to evaluate the quality of the representative data gotten by those methods. The comparisons are performed on six datasets and the results are analyzed by Friedman test with the corresponding post-hoc tests. The results indicate that KECA shows an excellent performance in both quality assessment criteria and clustering accuracy assessing. 展开更多
关键词 dimensionality reduction kernel entropy component analysis(KECA) kernel principal component analysis(KPCA) CLUSTERING
在线阅读 下载PDF
Principal component analysis and fine‑tuned vision transformation integrating model explainability for breast cancer prediction
11
作者 Huong Hoang Luong Phuc Phan Hong +4 位作者 Dat Vo Minh Thinh Nguyen Le Quang Anh Dinh The Nguyen Thai-Nghe Hai Thanh Nguyen 《Visual Computing for Industry,Biomedicine,and Art》 2025年第1期74-92,共19页
Breast cancer,which is the most commonly diagnosed cancers among women,is a notable health issues globally.Breast cancer is a result of abnormal cells in the breast tissue growing out of control.Histopathology,which r... Breast cancer,which is the most commonly diagnosed cancers among women,is a notable health issues globally.Breast cancer is a result of abnormal cells in the breast tissue growing out of control.Histopathology,which refers to the detection and learning of tissue diseases,has appeared as a solution for breast cancer treatment as it plays a vital role in its diagnosis and classification.Thus,considerable research on histopathology in medical and computer science has been conducted to develop an effective method for breast cancer treatment.In this study,a vision Transformer(ViT)was employed to classify tumors into two classes,benign and malignant,in the Breast Cancer Histopathological Database(BreakHis).To enhance the model performance,we introduced the novel multi-head locality large kernel self-attention during fine-tuning,achieving an accuracy of 95.94%at 100×magnification,thereby improving the accuracy by 3.34%compared to a standard ViT(which uses multi-head self-attention).In addition,the application of principal component analysis for dimensionality reduction led to an accuracy improvement of 3.34%,highlighting its role in mitigating overfitting and reducing the computational complexity.In the final phase,SHapley Additive exPlanations,Local Interpretable Model-agnostic Explanations,and Gradient-weighted Class Activation Mapping were used for the interpretability and explainability of machine-learning models,aiding in understanding the feature importance and local explanations,and visualizing the model attention.In another experiment,ensemble learning with VGGIN further boosted the performance to 97.13%accuracy.Our approach exhibited a 0.98%to 17.13%improvement in accuracy compared with state-of-the-art methods,establishing a new benchmark for breast cancer histopathological image classification. 展开更多
关键词 Vision Transformer Multi-head locality large kernel self-attention principal component analysis
在线阅读 下载PDF
Multivariate Cluster and Principle Component Analyses of Selected Yield Traits in Uzbek Bread Wheat Cultivars 被引量:2
12
作者 Shokista Sh. Adilova Dilafruz E. Qulmamatova +2 位作者 Saidmurad K. Baboev Tohir A. Bozorov Aleksey I. Morgunov 《American Journal of Plant Sciences》 2020年第6期903-912,共10页
Investigation of genetic diversity of geographically distant wheat genotypes is </span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">useful ... Investigation of genetic diversity of geographically distant wheat genotypes is </span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">useful approach in wheat breeding providing efficient crop varieties. This article presents multivariate cluster and principal component analyses (PCA) of some yield traits of wheat, such as thousand-kernel weight (TKW), grain number, grain yield and plant height. Based on the results, an evaluation of economically valuable attributes by eigenvalues made it possible to determine the components that significantly contribute to the yield of common wheat genotypes. Twenty-five genotypes were grouped into four clusters on the basis of average linkage. The PCA showed four principal components (PC) with eigenvalues ></span><span style="font-family:""> </span><span style="font-family:Verdana;">1, explaining approximately 90.8% of the total variability. According to PC analysis, the variance in the eigenvalues was </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">greatest (4.33) for PC-1, PC-2 (1.86) and PC-3 (1.01). The cluster analysis revealed the classification of 25 accessions into four diverse groups. Averages, standard deviations and variances for clusters based on morpho-physiological traits showed that the maximum average values for grain yield (742.2), biomass (1756.7), grains square meter (18</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;">373.7), and grains per spike (45.3) were higher in cluster C compared to other clusters. Cluster D exhibited the maximum thousand-kernel weight (TKW) (46.6). 展开更多
关键词 Bread Wheat principal component analysis Dispersion Cluster analysis Grain Yield Spike Number Per Square Meter Drought Stress Thousand-kernel Weight
在线阅读 下载PDF
Kernel Factor Analysis Algorithm with Varimax
13
作者 夏国恩 金炜东 张葛祥 《Journal of Southwest Jiaotong University(English Edition)》 2006年第4期394-399,共6页
Kernal factor analysis (KFA) with vafimax was proposed by using Mercer kernel function which can map the data in the original space to a high-dimensional feature space, and was compared with the kernel principle com... Kernal factor analysis (KFA) with vafimax was proposed by using Mercer kernel function which can map the data in the original space to a high-dimensional feature space, and was compared with the kernel principle component analysis (KPCA). The results show that the best error rate in handwritten digit recognition by kernel factor analysis with vadmax (4.2%) was superior to KPCA (4.4%). The KFA with varimax could more accurately image handwritten digit recognition. 展开更多
关键词 kernel factor analysis kernel principal component analysis Support vector machine Varimax ALGORITHM Handwritten digit recognition
在线阅读 下载PDF
Adaptive multiblock kernel principal component analysis for monitoring complex industrial processes 被引量:1
14
作者 Ying-wei ZHANG Yong-dong TENG 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2010年第12期948-955,共8页
Multiblock kernel principal component analysis (MBKPCA) has been proposed to isolate the faults and avoid the high computation cost. However, MBKPCA is not available for dynamic processes. To solve this problem, recur... Multiblock kernel principal component analysis (MBKPCA) has been proposed to isolate the faults and avoid the high computation cost. However, MBKPCA is not available for dynamic processes. To solve this problem, recursive MBKPCA is proposed for monitoring large scale processes. In this paper, we present a new recursive MBKPCA (RMBKPCA) algorithm, where the adaptive technique is adopted for dynamic characteristics. The proposed algorithm reduces the high computation cost, and is suitable for online model updating in the feature space. The proposed algorithm was applied to an industrial process for adaptive monitoring and found to efficiently capture the time-varying and nonlinear relationship in the process variables. 展开更多
关键词 Recursive multiblock kernel principal component analysis (RMBPCA) Dynamic process Nonlinear process
原文传递
Prediction of coal and gas outburst hazard using kernel principal component analysis and an enhanced extreme learning machine approach
15
作者 Kailong Xue Yun Qi +2 位作者 Hongfei Duan Anye Cao Aiwen Wang 《Geohazard Mechanics》 2024年第4期279-288,共10页
In order to enhance the accuracy and efficiency of coal and gas outburst prediction,a novel approach combining Kernel Principal Component Analysis(KPCA)with an Improved Whale Optimization Algorithm(IWOA)optimized extr... In order to enhance the accuracy and efficiency of coal and gas outburst prediction,a novel approach combining Kernel Principal Component Analysis(KPCA)with an Improved Whale Optimization Algorithm(IWOA)optimized extreme learning machine(ELM)is proposed for precise forecasting of coal and gas outburst disasters in mines.Firstly,based on the influencing factors of coal and gas outburst disasters,nine coupling indexes are selected,including gas pressure,geological structure,initial velocity of gas emission,and coal structure type.The correlation between each index was analyzed using the Pearson correlation coefficient matrix in SPSS 27,followed by extraction of the principal components of the original data through Kernel Principal Component Analysis(KPCA).The Whale Optimization Algorithm(WOA)was enhanced by incorporating adaptive weight,variable helix position update,and optimal neighborhood disturbance to augment its performance.The improved Whale Optimization Algorithm(IWOA)is subsequently employed to optimize the weight Φ of the Extreme Learning Machine(ELM)input layer and the threshold g of the hidden layer,thereby enhancing its predictive accuracy and mitigating the issue of"over-fitting"associated with ELM to some extent.The principal components extracted by KPCA were utilized as input,while the outburst risk grade served as output.Subsequently,a comparative analysis was conducted between these results and those obtained from WOA-SVC,PSO-BPNN,and SSA-RF models.The IWOA-ELM model accurately predicts the risk grade of coal and gas outburst disasters,with results consistent with actual situations.Compared to other models tested,the model's performance showed an increase in Ac by 0.2,0.3,and 0.2 respectively;P increased by 0.15,0.2167,and 0.1333 respectively;R increased by 0.25,0.3,and 0.2333 respectively;F1-Score increased by 0.2031,0.2607,and 0.1864 respectively;Kappa coefficient k increased by 0.3226,0.4762 and 0.3175,respectively.The practicality and stability of the IWOAELM model were verified through its application in a coal mine in Shanxi Province where the predicted values exactly matched the actual values.This indicates that this model is more suitable for predicting coal and gas outburst disaster risks. 展开更多
关键词 Coal and gas outburst Risk prediction kernel principal component analysis(KPCA) Improved whale optimization algorithm(IWOA) Extreme learning machine(ELM)
在线阅读 下载PDF
Multivariate time delay analysis based local KPCA fault prognosis approach for nonlinear processes 被引量:7
16
作者 Yuan Xu Ying Liu Qunxiong Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第10期1413-1422,共10页
Currently, some fault prognosis technology occasionally has relatively unsatisfied performance especially for in- cipient faults in nonlinear processes duo to their large time delay and complex internal connection. To... Currently, some fault prognosis technology occasionally has relatively unsatisfied performance especially for in- cipient faults in nonlinear processes duo to their large time delay and complex internal connection. To overcome this deficiency, multivariate time delay analysis is incorporated into the high sensitive local kernel principal component analysis. In this approach, mutual information estimation and Bayesian information criterion (BIC) are separately used to acquire the correlation degree and time delay of the process variables. Moreover, in order to achieve prediction, time series prediction by back propagation (BP) network is applied whose input is multivar- iate correlated time series other than the original time series. Then the multivariate time delayed series and future values obtained by time series prediction are combined to construct the input of local kernel principal component analysis (LKPCA) model for incipient fault prognosis. The new method has been exemplified in a sim- ple nonlinear process and the complicated Tennessee Eastman (TE) benchmark process. The results indicate that the new method has suoerioritv in the fault prognosis sensitivity over other traditional fault prognosis methods. 展开更多
关键词 Fault prognosis Time delay estimation Local kernel principal component analysis
在线阅读 下载PDF
用于基桩缺陷智能识别模型的低应变法数据分析方法研究
17
作者 韩剑飞 《江淮水利科技》 2026年第1期31-35,共5页
建立基桩缺陷智能识别模型需依赖全面且有效的样本数据集,以发挥其非线性回归和预测能力,获取用于机器学习的样本数据集是模型建立过程中的关键步骤。研究提出了一种基于核主成分分析的改进数据分析方法(PearsonKPCA),旨在为基桩缺陷智... 建立基桩缺陷智能识别模型需依赖全面且有效的样本数据集,以发挥其非线性回归和预测能力,获取用于机器学习的样本数据集是模型建立过程中的关键步骤。研究提出了一种基于核主成分分析的改进数据分析方法(PearsonKPCA),旨在为基桩缺陷智能识别模型提供可理解且充分的样本数据。研究结果显示:Pearson-KPCA算法在降低样本数据维度方面表现出显著效果,且经过该算法优化的样本数据集在基桩缺陷智能识别模型中的应用效果明显优于采用传统数据分析方法得到的样本数据集。研究为低应变法检测结果的智能分析提供了可靠的数据处理思路与方法。 展开更多
关键词 基桩缺陷识别 低应变法 Pearson-KPCA模型 特征提取 核主成分分析 数据分析
原文传递
基于KPCA与能量熵的气液两相流流动特性分析
18
作者 仝卫国 钟海增 +2 位作者 林礼榕 王用沛 李国智 《电力科学与工程》 2026年第1期48-55,共8页
提出一种基于核主成分分析与多元多尺度能量熵的气液两相流流动特性分析方法。通过电阻层析成像设备采集垂直管道气液两相流实验数据,采用核主成分分析(kernel principal component analysis,KPCA)和主成分分析分别处理原始数据得到低... 提出一种基于核主成分分析与多元多尺度能量熵的气液两相流流动特性分析方法。通过电阻层析成像设备采集垂直管道气液两相流实验数据,采用核主成分分析(kernel principal component analysis,KPCA)和主成分分析分别处理原始数据得到低维时间序列,结合多变量经验模态分解方法提取多元多尺度能量熵(multivariate multiscale energy entropy,MMEE)用以对比降维方法影响并分析流体的动态变化。结果表明,KPCA能保留原始数据中非线性特性并显现在MMEE的数据变化与流型转换关系中;结合熵值10尺度均值与5尺度拟合斜率构建的联合分布能实现高效准确的流型辨识。所提方法为气液两相流流动特性分析提供了兼具经济性与效率性的手段,也为更深层次的分析提供了更多元的可靠参数。 展开更多
关键词 核主成分分析 多元多尺度能量熵 气液两相流 流动特性分析 流型辨识
在线阅读 下载PDF
基于CNN-BiLSTM-SSA的锅炉再热器壁温预测模型 被引量:1
19
作者 徐世明 何至谦 +6 位作者 彭献永 商忠宝 范景玮 王俊略 曲舒杨 刘洋 周怀春 《动力工程学报》 北大核心 2026年第1期121-130,共10页
针对锅炉高温再热器壁温动态特点,提出了一种基于稀疏自注意力(SSA)、卷积神经网络(CNN)及双向长短期记忆神经网络(BiLSTM)相融合的再热器壁温软测量模型。首先,采用核主成分分析(KPCA)算法对原始候选变量进行筛选降维,选择前26个主成... 针对锅炉高温再热器壁温动态特点,提出了一种基于稀疏自注意力(SSA)、卷积神经网络(CNN)及双向长短期记忆神经网络(BiLSTM)相融合的再热器壁温软测量模型。首先,采用核主成分分析(KPCA)算法对原始候选变量进行筛选降维,选择前26个主成分变量作为模型的最终输入。其次,考虑利用CNN捕捉局部相关性,BiLSTM学习数据的长期序列依赖性的优势,使用卷积神经网络-双向长短期记忆神经网络(CNN-BiLSTM)捕捉时序数据中的短期和长期依赖关系,引入稀疏自注意力SSA机制,通过为不同特征部分分配自适应权重,从而增强CNN-BiLSTM模型的特征提取与建模能力,最后利用在役1000 MW超超临界锅炉的历史数据进行仿真实验。结果表明:CNN-BiLSTM-SSA模型在高温再热器壁温预测中的均方根误差(RMSE)、平均绝对误差(MAE)及平均绝对百分比误差(MAPE)分别为4.92℃、3.81℃和0.6241%,相应的指标均优于CNN、LSTM、BiLSTM、CNN-LSTM和CNN-BiLSTM模型。 展开更多
关键词 再热器壁温软测量 深度学习 卷积神经网络 长短期记忆网络 注意力机制 核主成分分析 CNN-BiLSTM
在线阅读 下载PDF
上一页 1 2 60 下一页 到第
使用帮助 返回顶部