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Phase transition extracted by principal component analysis in the disordered Moore–Read state
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作者 Na Jiang Shuaixin Fu +1 位作者 Zhengzhi Ma Lian Wang 《Chinese Physics B》 2025年第4期552-558,共7页
We study the influence of disorder on the Moore–Read state by principal component analysis(PCA),which is one of the ground state candidates for the 5/2 fractional Hall state.By using PCA,the topological features of t... We study the influence of disorder on the Moore–Read state by principal component analysis(PCA),which is one of the ground state candidates for the 5/2 fractional Hall state.By using PCA,the topological features of the ground state wave functions with different disorder strengths can be distilled.As the disorder strength increases,the Moore–Read state will be destroyed.We explore the phase transition by analyzing the overlaps between the random sample wave functions and the topologically distilled state.The cross-point between the amplitudes of the principal component and its counterpart is the phase transition point.Additionally,the origin of the second component comes from the excited states,which is different from the Laughlin state. 展开更多
关键词 fractional quantum Hall phase transition principal component analysis
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FUZZY WITHIN-CLASS MATRIX PRINCIPAL COMPONENT ANALYSIS AND ITS APPLICATION TO FACE RECOGNITION 被引量:3
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作者 朱玉莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期141-147,共7页
Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of sampl... Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of samples. As a result, the extracted features cannot provide enough useful information for distinguishing pat- tern from one another, and further resulting in degradation of classification performance. To fullly use class in- formation of samples, a novel method, called the fuzzy within-class MatPCA (F-WMatPCA)is proposed. F-WMatPCA utilizes the fuzzy K-nearest neighbor method(FKNN) to fuzzify the class membership degrees of a training sample and then performs fuzzy MatPCA within these patterns having the same class label. Due to more class information is used in feature extraction, F-WMatPCA can intuitively improve the classification perfor- mance. Experimental results in face databases and some benchmark datasets show that F-WMatPCA is effective and competitive than MatPCA. The experimental analysis on face image databases indicates that F-WMatPCA im- proves the recognition accuracy and is more stable and robust in performing classification than the existing method of fuzzy-based F-Fisherfaces. 展开更多
关键词 face recognition principal component analysis pca matrix pattern pca(Matpca fuzzy K-nearest neighbor(FKNN) fuzzy within-class Matpca(F-WMatpca
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基于PCA-BPNN的桥梁爆炸荷载时程预测
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作者 杜晓庆 何益平 +2 位作者 邱涛 程帅 张德志 《爆炸与冲击》 北大核心 2025年第3期77-91,共15页
人工智能方法是预测爆炸荷载的新手段,但现有方法主要用于预测爆炸冲击波的超压峰值或冲量,而用于预测反射超压时程的研究不多。针对这一问题,以平面冲击波绕射桥梁主梁为对象,提出了一种基于主成分分析(principal components analysis,... 人工智能方法是预测爆炸荷载的新手段,但现有方法主要用于预测爆炸冲击波的超压峰值或冲量,而用于预测反射超压时程的研究不多。针对这一问题,以平面冲击波绕射桥梁主梁为对象,提出了一种基于主成分分析(principal components analysis,PCA)和误差反向传播神经网络(backpropagation neural network,BPNN)的桥梁爆炸冲击波反射超压时程预测模型。该预测模型利用PCA降维处理时程数据,基于多任务学习的BPNN算法,提出了考虑超压峰值和冲量峰值影响的损失函数,使模型能有效预测不同入射超压下的桥梁冲击波荷载时程。通过分析多任务学习模型、多输入单输出模型和多输入多输出模型等3种BPNN模型,发现多任务学习模型的预测精度最高,而多输入多输出模型难以有效适应当前预测任务需求。采用多任务学习模型预测得到的桥梁表面各测点位置的反射超压时程、超压峰值精度较高,决定系数R2分别为0.792和0.987,作用在箱梁上的合力时程和扭矩时程预测值也与数值模拟值较为吻合。同时,该模型对内插值预测的表现优于外推值预测,但其在预测外推值方面同样展现出了一定的能力。 展开更多
关键词 爆炸荷载预测 反射超压时程 误差反向传播神经网络 主成分分析 多任务学习
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PCA-BP神经网络模型在拖拉机发动机故障诊断中的应用
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作者 杨健 《农机化研究》 北大核心 2025年第3期254-258,共5页
拖拉机发动机故障诊断是指通过对拖拉机发动机的运行状态、传感器数据等信息进行分析和处理,识别出发动机故障的类型和位置,及时准确地诊断拖拉机发动机故障,对于提高农机装备的使用效率和经济效益具有重要的意义。为此,基于主成分分析(... 拖拉机发动机故障诊断是指通过对拖拉机发动机的运行状态、传感器数据等信息进行分析和处理,识别出发动机故障的类型和位置,及时准确地诊断拖拉机发动机故障,对于提高农机装备的使用效率和经济效益具有重要的意义。为此,基于主成分分析(PCA)算法对拖拉机发动机的传感器数据进行降维处理,并使用BP神经网络对降维后的数据进行分类识别,以实现拖拉机发动机故障的诊断。试验结果表明:PCA-BP神经网络模型可以准确地诊断拖拉机发动机的多种故障,相比于传统的BP神经网络模型,具有更高的准确率和更好的泛化能力,表明PCA-BP神经网络模型在拖拉机发动机故障诊断中具有较大的应用前景。 展开更多
关键词 拖拉机发动机 故障诊断 主成分分析 BP神经网络
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Remaining Useful Life Prediction of Aeroengine Based on Principal Component Analysis and One-Dimensional Convolutional Neural Network 被引量:4
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作者 LYU Defeng HU Yuwen 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第5期867-875,共9页
In order to directly construct the mapping between multiple state parameters and remaining useful life(RUL),and reduce the interference of random error on prediction accuracy,a RUL prediction model of aeroengine based... In order to directly construct the mapping between multiple state parameters and remaining useful life(RUL),and reduce the interference of random error on prediction accuracy,a RUL prediction model of aeroengine based on principal component analysis(PCA)and one-dimensional convolution neural network(1D-CNN)is proposed in this paper.Firstly,multiple state parameters corresponding to massive cycles of aeroengine are collected and brought into PCA for dimensionality reduction,and principal components are extracted for further time series prediction.Secondly,the 1D-CNN model is constructed to directly study the mapping between principal components and RUL.Multiple convolution and pooling operations are applied for deep feature extraction,and the end-to-end RUL prediction of aeroengine can be realized.Experimental results show that the most effective principal component from the multiple state parameters can be obtained by PCA,and the long time series of multiple state parameters can be directly mapped to RUL by 1D-CNN,so as to improve the efficiency and accuracy of RUL prediction.Compared with other traditional models,the proposed method also has lower prediction error and better robustness. 展开更多
关键词 AEROENGINE remaining useful life(RUL) principal component analysis(pca) one-dimensional convolution neural network(1D-CNN) time series prediction state parameters
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Laser-induced breakdown spectroscopy applied to the characterization of rock by support vector machine combined with principal component analysis 被引量:6
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作者 杨洪星 付洪波 +3 位作者 王华东 贾军伟 Markus W Sigrist 董凤忠 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期290-295,共6页
Laser-induced breakdown spectroscopy(LIBS) is a versatile tool for both qualitative and quantitative analysis.In this paper,LIBS combined with principal component analysis(PCA) and support vector machine(SVM) is... Laser-induced breakdown spectroscopy(LIBS) is a versatile tool for both qualitative and quantitative analysis.In this paper,LIBS combined with principal component analysis(PCA) and support vector machine(SVM) is applied to rock analysis.Fourteen emission lines including Fe,Mg,Ca,Al,Si,and Ti are selected as analysis lines.A good accuracy(91.38% for the real rock) is achieved by using SVM to analyze the spectroscopic peak area data which are processed by PCA.It can not only reduce the noise and dimensionality which contributes to improving the efficiency of the program,but also solve the problem of linear inseparability by combining PCA and SVM.By this method,the ability of LIBS to classify rock is validated. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) principal component analysispca support vector machine(SVM) lithology identification
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Computational Intelligence Prediction Model Integrating Empirical Mode Decomposition,Principal Component Analysis,and Weighted k-Nearest Neighbor 被引量:2
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作者 Li Tang He-Ping Pan Yi-Yong Yao 《Journal of Electronic Science and Technology》 CAS CSCD 2020年第4期341-349,共9页
On the basis of machine leaning,suitable algorithms can make advanced time series analysis.This paper proposes a complex k-nearest neighbor(KNN)model for predicting financial time series.This model uses a complex feat... On the basis of machine leaning,suitable algorithms can make advanced time series analysis.This paper proposes a complex k-nearest neighbor(KNN)model for predicting financial time series.This model uses a complex feature extraction process integrating a forward rolling empirical mode decomposition(EMD)for financial time series signal analysis and principal component analysis(PCA)for the dimension reduction.The information-rich features are extracted then input to a weighted KNN classifier where the features are weighted with PCA loading.Finally,prediction is generated via regression on the selected nearest neighbors.The structure of the model as a whole is original.The test results on real historical data sets confirm the effectiveness of the models for predicting the Chinese stock index,an individual stock,and the EUR/USD exchange rate. 展开更多
关键词 Empirical mode decomposition(EMD) k-nearest neighbor(KNN) principal component analysis(pca) time series
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Characterization of three-dimensional channel reservoirs using ensemble Kalman filter assisted by principal component analysis 被引量:2
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作者 Byeongcheol Kang Hyungsik Jung +1 位作者 Hoonyoung Jeong Jonggeun Choe 《Petroleum Science》 SCIE CAS CSCD 2020年第1期182-195,共14页
Ensemble-based analyses are useful to compare equiprobable scenarios of the reservoir models.However,they require a large suite of reservoir models to cover high uncertainty in heterogeneous and complex reservoir mode... Ensemble-based analyses are useful to compare equiprobable scenarios of the reservoir models.However,they require a large suite of reservoir models to cover high uncertainty in heterogeneous and complex reservoir models.For stable convergence in ensemble Kalman filter(EnKF),increasing ensemble size can be one of the solutions,but it causes high computational cost in large-scale reservoir systems.In this paper,we propose a preprocessing of good initial model selection to reduce the ensemble size,and then,EnKF is utilized to predict production performances stochastically.In the model selection scheme,representative models are chosen by using principal component analysis(PCA)and clustering analysis.The dimension of initial models is reduced using PCA,and the reduced models are grouped by clustering.Then,we choose and simulate representative models from the cluster groups to compare errors of production predictions with historical observation data.One representative model with the minimum error is considered as the best model,and we use the ensemble members near the best model in the cluster plane for applying EnKF.We demonstrate the proposed scheme for two 3D models that EnKF provides reliable assimilation results with much reduced computation time. 展开更多
关键词 Channel reservoir CHARACTERIZATION MODEL selection scheme EGG MODEL principal component analysis(pca) ENSEMBLE KALMAN filter(EnKF) History matching
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Improved Face Recognition Method Using Genetic Principal Component Analysis 被引量:2
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作者 E.Gomathi K.Baskaran 《Journal of Electronic Science and Technology》 CAS 2010年第4期372-378,共7页
An improved face recognition method is proposed based on principal component analysis (PCA) compounded with genetic algorithm (GA), named as genetic based principal component analysis (GPCA). Initially the eigen... An improved face recognition method is proposed based on principal component analysis (PCA) compounded with genetic algorithm (GA), named as genetic based principal component analysis (GPCA). Initially the eigenspace is created with eigenvalues and eigenvectors. From this space, the eigenfaces are constructed, and the most relevant eigenfaees have been selected using GPCA. With these eigenfaees, the input images are classified based on Euclidian distance. The proposed method was tested on ORL (Olivetti Research Labs) face database. Experimental results on this database demonstrate that the effectiveness of the proposed method for face recognition has less misclassification in comparison with previous methods. 展开更多
关键词 EIGENFACES EIGENVECTORS face recognition genetic algorithm principal component analysis.
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Energy-efficient Scheme for Multiple Access Network Selection Using Principal Component Analysis 被引量:2
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作者 王莉 王景尧 +2 位作者 魏翼飞 马跃 满毅 《China Communications》 SCIE CSCD 2011年第3期133-144,共12页
This paper brings forward a novel dynamic multiple access network selection scheme(NDMAS),which could achieve less energy loss and improve the poor adaptive capability caused by the variable network parameters.Firstly... This paper brings forward a novel dynamic multiple access network selection scheme(NDMAS),which could achieve less energy loss and improve the poor adaptive capability caused by the variable network parameters.Firstly,a multiple access network selection mathematical model based on information theory is presented.From the perspective of information theory,access selection is essentially a process to reduce the information entropy in the system.It can be found that the lower the information entropy is,the better the system performance fulfills.Therefore,this model is designed to reduce the information entropy by removing redundant parameters,and to avoid the computational cost as well.Secondly,for model implementation,the Principal Component Analysis(PCA) is employed to process the observation data to find out the related factors which affect the users most.As a result,the information entropy is decreased.Theoretical analysis proves that system loss and computational complexity have been decreased by using the proposed approach,while the network QoS and accuracy are guaranteed.Finally,simulation results show that our scheme achieves much better system performance in terms of packet delay,throughput and call blocking probability than other currently existing ones. 展开更多
关键词 multiple access network selection information entropy quality of service principal component analysis
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Grey Relational Analysis Coupled with Principal Component Analysis Method For Optimization Design of Novel Crash Box Structure 被引量:1
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作者 Shuang Wang Dengfeng Wang 《Journal of Beijing Institute of Technology》 EI CAS 2019年第3期577-584,共8页
Crashworthiness and lightweight optimization design of the crash box are studied in this paper. For the initial model, a physical test was performed to verify the model. Then, a parametric model using mesh morphing te... Crashworthiness and lightweight optimization design of the crash box are studied in this paper. For the initial model, a physical test was performed to verify the model. Then, a parametric model using mesh morphing technology is used to optimize and decrease the maximum collision force (MCF) and increase specific energy absorption (SEA) while ensure mass is not increased. Because MCF and SEA are two conflicting objectives, grey relational analysis (GRA) and principal component analysis (PCA) are employed for design optimization of the crash box. Furthermore, multi-objective analysis can convert to a single objective using the grey relational grade (GRG) simultaneously, hence, the proposed method can obtain the optimal combination of design parameters for the crash box. It can be concluded that the proposed method decreases the MCF and weight to 16.7% and 29.4% respectively, while increasing SEA to 16.4%. Meanwhile, the proposed method in comparison to the conventional NSGA-Ⅱ method, reduces the time cost by 103%. Hence, the proposed method can be properly applied to the optimization of the crash box. 展开更多
关键词 CRASH box optimization maximum COLLISION force (MCF) specific energy absorption (SEA) GREY RELATIONAL analysis (GRA) principal component analysis (pca)
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Selection of tree species by principal component analysis for abandoned farmland in southeastern Horqin Sandy Land,China 被引量:1
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作者 Peng Meng Jing Liu Xuefeng Bai 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第2期475-486,共12页
With changes in global climate and land use,the area of desertified farmland in southeastern Horqin Sandy Land(HSL)has increased in recent years,and farmlands are being abandoned.These abandoned farmlands(AFs)nega-tiv... With changes in global climate and land use,the area of desertified farmland in southeastern Horqin Sandy Land(HSL)has increased in recent years,and farmlands are being abandoned.These abandoned farmlands(AFs)nega-tively impact the local ecology.Therefore,the aim of the present study was to select suitable trees and shrubs for those AFs to prevent and control the desertification tendency.In this study,three AFs were fenced for 2 years,then 37 arbor and shrub species or varieties of 21 families were planted in the fenced AFs and grown for 10 years.The ecological adaptability of the species was evaluated and ranked using a principal component analysis.The results showed that the biodiversity of the AFs significantly improved after 2 years of fencing;the Shannon-Wiener index and species rich-ness of perennial grasses and forbs were 1.45 and 3.6 times higher,respectively,than for the unfenced AF.Among all species planted in fenced AFs,nine tree species had posi-tive comprehensive F(CF)values;Pinus sylvestris(Russian Shira steppe provenance),Populus alba‘Berolinensis’and Gleditsia triacanthos had CF greater than 1,and the first(PC1),second(PC2)and third(PC3)principal component values(F_(1),F_(2),F_(3))were all positive.Among the shrubs,only Lespedeza bicolor and Rosa xanthina f.normalis had CF greater than 0.All these results suggest that fencing improves biodiversity and that planting trees and shrubs that have higher CF values on the basis of fencing is an effective way to green and beautify AFs in HSL. 展开更多
关键词 Horqin Sandy Land Fenced abandoned farmland principal component analysis Tree species selection
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基于ICEEMDAN-KPCA-ICPA-LSTM的光伏发电功率预测
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作者 姚钦才 向文国 +2 位作者 陈时熠 曹敬 郑涛 《动力工程学报》 北大核心 2025年第3期374-382,共9页
光伏发电预测对于新型电力系统的平稳运行至关重要。针对光伏发电短期预测,提出了一种融合改进的完全自适应噪声集合经验模态分解(ICEEMDAN)、核主成分分析(KPCA)和改进的食肉植物算法(ICPA)与长短期记忆网络(LSTM)的光伏发电预测方法... 光伏发电预测对于新型电力系统的平稳运行至关重要。针对光伏发电短期预测,提出了一种融合改进的完全自适应噪声集合经验模态分解(ICEEMDAN)、核主成分分析(KPCA)和改进的食肉植物算法(ICPA)与长短期记忆网络(LSTM)的光伏发电预测方法。首先,该方法通过ICEEMDAN提取气象数据中非线性信号的隐含特征;其次,采用核主成分分析降低分解后产生的冗余信息,并根据主成分贡献率大小选取模型输入参数;最后,对食肉植物算法(CPA)进行改进,构建ICPA-LSTM模型,并开展了晴天、雨天、多云和多变天气4种典型天气类型下光伏发电功率预测校验。结果表明:在不同天气情况下,所提模型的决定系数R 2均大于99%,相较于对照模型具有更好的预测性能。 展开更多
关键词 光伏发电预测 ICEEMDAN 长短期记忆网络 食肉植物算法 核主成分分析
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基于改进型PCA全极化雷达回波信号融合的动目标检测方法
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作者 庞岳 岳富占 +4 位作者 夏正欢 张闯 王洪强 高文宁 张瑶 《现代雷达》 北大核心 2025年第2期126-133,共8页
树林遮蔽场景下的雷达回波信号存在信噪比低、信号幅度和相位起伏等问题,极大地增加了目标检测难度。针对信号级中低分辨率雷达探测树林遮蔽目标的应用需求,文中研究了一种基于改进型主成分分析(PCA)全极化雷达回波信号融合的动目标检... 树林遮蔽场景下的雷达回波信号存在信噪比低、信号幅度和相位起伏等问题,极大地增加了目标检测难度。针对信号级中低分辨率雷达探测树林遮蔽目标的应用需求,文中研究了一种基于改进型主成分分析(PCA)全极化雷达回波信号融合的动目标检测方法。该方法首先在杂波背景下提取动目标信号,并利用改进型PCA进行全极化雷达回波信号融合;然后分别在时间维和距离维进行目标检测,并通过非相参积累方法重检测,有效排除目标混叠和虚警干扰,从而检测出目标并提取了其关注区域;最后通过自主研发的L波段全极化雷达系统,对该方法进行了实验验证。实验结果表明:该方法对于树林遮蔽环境下动目标具有很好的检测效果,显著提升了L波段全极化雷达在树林遮蔽条件下的目标检测性能。 展开更多
关键词 L波段全极化雷达 主成分分析 数据融合 树林遮蔽场景 目标检测
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基于PCA和自联想神经网络的核环境冷挤压切割刀具状态监测
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作者 袁沛 蒋君侠 +2 位作者 马飞 金杰峰 来建良 《浙江大学学报(工学版)》 北大核心 2025年第3期606-615,共10页
在高放射性环境中,传感器部署受限,传动链噪声干扰,冷挤压切割刀具一致性差.为此提出基于外置电机旋转轴与进给轴电机扭矩信号的时频域统计、主成分分析(PCA)与自联想神经网络(AANN)相结合的刀具状态监测模型.基于旋转电机及进给电机扭... 在高放射性环境中,传感器部署受限,传动链噪声干扰,冷挤压切割刀具一致性差.为此提出基于外置电机旋转轴与进给轴电机扭矩信号的时频域统计、主成分分析(PCA)与自联想神经网络(AANN)相结合的刀具状态监测模型.基于旋转电机及进给电机扭矩波形提取时域统计特征及小波包能量特征形成原始训练集,利用原始训练集初步训练AANN模型,使用PCA重构原始训练集用于优化AANN模型局部结构参数,形成PCA-AANN刀具状态监测模型.基于实际样机的切割试验采集扭矩数据,对提出的PCA-AANN和现有AANN模型进行分析对比,结果表明PCA的引入有助于提高AANN模型鲁棒性,能有效降低刀具工作状态误报率,实现放射性环境下刀具状态的准确监测.所提方法为放射性环境中类似长传动链设备的状态监测提供了借鉴. 展开更多
关键词 放射性 刀具状态监测 时域统计 小波包分解 主成分分析 自联想神经网络
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基于ROAV法与PCA-TOPSIS法冰葡萄酒香气质量综合评价
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作者 张杨 曲绎霖 +2 位作者 孙永德 孔维府 李红娟 《中国酿造》 北大核心 2025年第1期258-268,共11页
该研究以四款代表性国产冰酒(编号为1号~4号)为研究对象,采用顶空-固相微萃取(HS-SPME)结合气质联用(GC-MS)技术测定冰酒的挥发性香气成分,并构建主成分分析(PCA)-优劣解距离法(TOPSIS)模型对冰酒香气品质进行分析评价。结果表明,四款... 该研究以四款代表性国产冰酒(编号为1号~4号)为研究对象,采用顶空-固相微萃取(HS-SPME)结合气质联用(GC-MS)技术测定冰酒的挥发性香气成分,并构建主成分分析(PCA)-优劣解距离法(TOPSIS)模型对冰酒香气品质进行分析评价。结果表明,四款冰酒共检测出118种挥发性香气成分,其中脂肪酸乙酯类18种、乙酸酯类8种、其他酯类24种、醇类13种、萜烯类12种、降异戊二烯衍生物4种、酸类5种、醛酮类9种、芳香族化合物15种、其他类10种;四款冰酒中香气成分的种类与含量差别显著。通过相对气味活度值(ROAV)筛选出22种重要香气物质(ROAV>0.1),10种关键香气物质(ROAV>1)。相关性结果表明,辛酸乙酯与苯乙醛呈显著负相关(P<0.05)、与大马士酮呈极显著负相关(P<0.01);大马士酮与苯乙醛呈显著正相关(P<0.05)、与癸酸乙酯和辛酸乙酯呈极显著负相关(P<0.01)。PCA-TOPSIS得出四款冰酒的香气评价结果Si(相对接近度)依次为0.804(4号)>0.572(2号)>0.411(1号)>0.229(3号),表明4号冰酒香气品质最优。 展开更多
关键词 冰葡萄酒 香气质量评价 相对气味活度值 主成分分析法 优劣解距离法
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基于RFECV-RF和PCA-LightGBM的水电机组劣化趋势评估
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作者 陈亦真 宋旭峰 李超顺 《水电能源科学》 北大核心 2025年第3期196-199,172,共5页
为确保水电机组安全稳定运行,提出一种基于RFECV-RF和PCA-LightGBM的水电机组劣化趋势评估方法。首先利用基于随机森林的交叉验证递归特征消除方法(RFECV-RF)对工况参数进行筛选,并利用主成分分析(PCA)方法对关键工况参数进行降维处理,... 为确保水电机组安全稳定运行,提出一种基于RFECV-RF和PCA-LightGBM的水电机组劣化趋势评估方法。首先利用基于随机森林的交叉验证递归特征消除方法(RFECV-RF)对工况参数进行筛选,并利用主成分分析(PCA)方法对关键工况参数进行降维处理,提取其中的关键信息;然后以轻量梯度提升机(LightGBM)拟合工况参数与振摆值之间的映射关系建立健康模型;最后根据机组运行数据与健康模型,生成机组劣化度,实现对机组劣化状态的评估。实例分析结果表明,与其他模型相比,所提模型精度更高、运算资源消耗更少。 展开更多
关键词 水电机组 劣化评估 主成分分析 随机森林 RFECV LightGBM
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Beam position monitor troubleshooting by using principal component analysis in Shanghai Synchrotron Radiation Facility 被引量:1
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作者 陈之初 冷用斌 +2 位作者 袁任贤 阎映炳 赖龙伟 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第2期7-12,共6页
Beam position monitors(BPMs)have been widely used in all kinds of measurement systems,feedback systems and other areas in particle accelerator field these days.The malfunction of a single BPM can cause serious consequ... Beam position monitors(BPMs)have been widely used in all kinds of measurement systems,feedback systems and other areas in particle accelerator field these days.The malfunction of a single BPM can cause serious consequences such as the failure of the orbit feedback and the transverse feedback.A troubleshooting has been made to prevent the defective BPMs from affecting the accuracy and stability of the storage ring in Shanghai Synchrotron Radiation Facility(SSRF).Different types of malfunctions have been successfully identified by using the idea of principal component analysis(PCA). 展开更多
关键词 上海同步辐射装置 主成分分析法 光位置检测器 故障排除 反馈系统 粒子加速器 BPM 测量系统
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Compressive Sensing Sparse Sampling Method for Composite Material Based on Principal Component Analysis
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作者 Sun Yajie Gu Feihong +1 位作者 Ji Sai Wang Lihua 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第2期282-289,共8页
Signals can be sampled by compressive sensing theory with a much less rate than those by traditional Nyquist sampling theorem,and reconstructed with high probability,only when signals are sparse in the time domain or ... Signals can be sampled by compressive sensing theory with a much less rate than those by traditional Nyquist sampling theorem,and reconstructed with high probability,only when signals are sparse in the time domain or a transform domain.Most signals are not sparse in real world,but can be expressed in sparse form by some kind of sparse transformation.Commonly used sparse transformations will lose some information,because their transform bases are generally fixed.In this paper,we use principal component analysis for data reduction,and select new variable with low dimension and linearly correlated to the original variable,instead of the original variable with high dimension,thus the useful data of the original signals can be included in the sparse signals after dimensionality reduction with maximize portability.Therefore,the loss of data can be reduced as much as possible,and the efficiency of signal reconstruction can be improved.Finally,the composite material plate is used for the experimental verification.The experimental result shows that the sparse representation of signals based on principal component analysis can reduce signal distortion and improve signal reconstruction efficiency. 展开更多
关键词 principal component analysis COMPRESSIVE sensing SPARSE REPRESENTATION SIGNAL RECONSTRUCTION
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Biomass estimation of Shorea robusta with principal component analysis of satellite data
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作者 Nilanchal Patel Arnab Majumdar 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期469-474,524,共7页
Spatio-temporal assessment of the above ground biomass (AGB) is a cumbersome task due to the difficulties associated with the measurement of different tree parameters such as girth at breast height and height of tre... Spatio-temporal assessment of the above ground biomass (AGB) is a cumbersome task due to the difficulties associated with the measurement of different tree parameters such as girth at breast height and height of trees. The present research was conducted in the campus of Birla Institute of Technology, Mesra, Ranchi, India, which is predomi- nantly covered by Sal (Shorea robusta C. F. Gaertn). Two methods of regression analysis was employed to determine the potential of remote sensing parameters with the AGB measured in the field such as linear regression analysis between the AGB and the individual bands, principal components (PCs) of the bands, vegetation indices (VI), and the PCs of the VIs respectively and multiple linear regression (MLR) analysis be- tween the AGB and all the variables in each category of data. From the linear regression analysis, it was found that only the NDVI exhibited regression coefficient value above 0.80 with the remaining parameters showing very low values. On the other hand, the MLR based analysis revealed significantly improved results as evidenced by the occurrence of very high correlation coefficient values of greater than 0.90 determined between the computed AGB from the MLR equations and field-estimated AGB thereby ascertaining their superiority in providing reliable estimates of AGB. The highest correlation coefficient of 0.99 is found with the MLR involving PCs of VIs. 展开更多
关键词 above ground biomass spectral response modeling vegetation indices principal component analysis linear and multiple regression analysis.
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