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MOVING TARGETS PATTERN RECOGNITION BASED ON THE WAVELET NEURAL NETWORK
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作者 GeGuangying ChenLili XuJianjian 《Journal of Electronics(China)》 2005年第3期321-328,共8页
Based on pattern recognition theory and neural network technology, moving objects automatic detection and classification method integrating advanced wavelet analysis are discussed in detail. An algorithm of moving tar... Based on pattern recognition theory and neural network technology, moving objects automatic detection and classification method integrating advanced wavelet analysis are discussed in detail. An algorithm of moving targets pattern recognition on the combination of inter-frame difference and wavelet neural network is presented. The experimental results indicate that the designed BP wavelet network using this algorithm can recognize and classify moving targets rapidly and effectively. 展开更多
关键词 移动目标检测 模式识别 微波神经网络 目标分类
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Fault Pattern Recognition of Rolling Bearing Based on Wavelet Packet Decomposition and BP Network
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作者 Liangpei Huang Chaowei Wu Jing Wang 《信息工程期刊(中英文版)》 2015年第1期7-13,共7页
关键词 滚动轴承故障 故障模式识别 BP网络模型 小波包分解 BP神经网络 振动信号 模式识别技术 能量特征
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Application of Wavelet Analysis toInterference Elimination for Geochemical Hydrocarbon Exploration 被引量:7
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作者 Zhang Liuping Ruan Tianjian Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 2000年第1期91-93,共3页
Interference in the data of geochemical hydrocarbon exploration is a large obstacle for anomaly recognition. The multiresolution analysis of wavelet analysis can extract the information at different scales so as to pr... Interference in the data of geochemical hydrocarbon exploration is a large obstacle for anomaly recognition. The multiresolution analysis of wavelet analysis can extract the information at different scales so as to provide a powerful tool for information analysis and processing. Based on the analysis of the geometric nature of hydrocarbon anomalies and background, Mallat wavelet and symmetric border treatment are selected and data pre-processing (logarithm-normalization) is established. This approach provide good results in Shandong and Inner Mongolia, China. It is demonstrated that this approach overcome the disadvantage of backgound variation in the window (interference in window), used in moving average, frame filtering and spatial and scaling modeling methods. 展开更多
关键词 geochemical exploration petroleum exploration interference elimination wavelet analysis data processing anomaly recognition.
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New pattern recognition system in the e-nose for Chinese spirit identification 被引量:4
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作者 曾慧 李强 谷宇 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期164-169,共6页
This paper presents a new pattern recognition system for Chinese spirit identification by using the polymer quartz piezoelectric crystal sensor based e-nose. The sensors are designed based on quartz crystal microbala... This paper presents a new pattern recognition system for Chinese spirit identification by using the polymer quartz piezoelectric crystal sensor based e-nose. The sensors are designed based on quartz crystal microbalance(QCM) principle,and they could capture different vibration frequency signal values for Chinese spirit identification. For each sensor in an8-channel sensor array, seven characteristic values of the original vibration frequency signal values, i.e., average value(A),root-mean-square value(RMS), shape factor value(S_f), crest factor value(C_f), impulse factor value(I_f), clearance factor value(CL_f), kurtosis factor value(K_v) are first extracted. Then the dimension of the characteristic values is reduced by the principle components analysis(PCA) method. Finally the back propagation(BP) neutral network algorithm is used to recognize Chinese spirits. The experimental results show that the recognition rate of six kinds of Chinese spirits is 93.33% and our proposed new pattern recognition system can identify Chinese spirits effectively. 展开更多
关键词 new pattern recognition system polymer quartz piezoelectric crystal sensor e-nose principle com-ponents analysis (PCA) back propagation (BP) algorithm Chinese spirit identification
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Evaluation of echo features of ultrasonic flaws and its intelligent pattern recognition 被引量:1
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作者 刚铁 吴林 《China Welding》 EI CAS 1997年第1期22-27,共6页
In this paper, three types of weld flaw were taken as target, evaluation and recognition of flaw echo features were studied. On the basis of experimental study and theoretical analysis, 26 features have been extracted... In this paper, three types of weld flaw were taken as target, evaluation and recognition of flaw echo features were studied. On the basis of experimental study and theoretical analysis, 26 features have been extracted from each echo samples. A method which is based on the xtatislical hypothesis testing and used for feature evaluation and optimum subset selection was explored. Thus, the dimensionality reduction of feature space was brought out, and simultaneously the amount of calculation was decreased. An intelligent pattern classifier with B-P type neural network was constructed which was characterized by high speed and accuracy for learning. Using a half of total samples as training set and others as testing set, the learning efficiency and the classification ability of network model were studied. The results of experiment showed that the learning rate of different training samples was about 100%. The results of recognition was satisfactory when the optimum feature subset was taken as the sample's feature vectors. The average recognition rate of three type flaws was about 87.6%, and the best recognition rate amounted to 97%. 展开更多
关键词 ultrasonic detection feature analysis pattern recognition
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A systematic method based on statistical pattern recognition for estimating product quality on-line 被引量:1
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作者 Guang Li, Huade Li, Shaoyuan Sun, and Zhengguang XuInformation Engineering School, University of Science and Technology Beijing, Beijing 100083, China 《Journal of University of Science and Technology Beijing》 CSCD 2003年第1期69-73,共5页
To avoid the complexity of building mechanistic models by studying the inner nature of the object, a systematic method based on statistical pattern recognition is developed in order to estimate the product quality on-... To avoid the complexity of building mechanistic models by studying the inner nature of the object, a systematic method based on statistical pattern recognition is developed in order to estimate the product quality on-line. The mapping relationship between a feature space and a product quality space can be built by using regression analysis, and in applying clustering analysis the product quality space can be partitioned automatically. Eventually, estimating product quality on-line can be accomplished by sorting the mapped data in the partitioned quality space. A concrete problem is proposed which has a relatively small ratio of training data to input variables. By implementing the method mentioned above, a satisfying result has been achieved. Furthermore, the further question about choosing suitable mapping methods is briefly discussed. 展开更多
关键词 pattern recognition regression analysis clustering analysis ISODATA algorithm sorting algorithm
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Medical Image Segmentation Based on Wavelet Analysis and Gradient Vector Flow
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作者 Ji Zhao Lina Zhang Minmin Yin 《Journal of Software Engineering and Applications》 2014年第12期1019-1030,共12页
Medical image segmentation is one of the key technologies in computer aided diagnosis. Due to the complexity and diversity of medical images, the wavelet multi-scale analysis is introduced into GVF (gradient vector fl... Medical image segmentation is one of the key technologies in computer aided diagnosis. Due to the complexity and diversity of medical images, the wavelet multi-scale analysis is introduced into GVF (gradient vector flow) snake model. The modulus values of each scale and phase angle values are calculated using wavelet transform, and the local maximum points of modulus values, which are the contours of the object edges, are obtained along phase angle direction at each scale. Then, location of the edges of the object and segmentation is implemented by GVF snake model. The experiments on some medical images show that the improved algorithm has small amount of computation, fast convergence and good robustness to noise. 展开更多
关键词 pattern recognition IMAGE Segmentation GVF SNAKE Model wavelet MULTI-SCALE analysis MEDICAL IMAGE
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Application of wavelet transform in feature extraction and pattern recognition of wideband echoes 被引量:8
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作者 ZHAO Jianping HUANG Jianguo ZHANG Huafeng(College of Marine Engineering, Northwestern Polytechnical University Xi’an 710072) 《Chinese Journal of Acoustics》 1998年第3期213-220,共8页
A novel approach to extract edge features from wideband echo is proposed. The set of extracted features not only represents the echo waveform in a concise way, but also is sufficient and well suited for classification... A novel approach to extract edge features from wideband echo is proposed. The set of extracted features not only represents the echo waveform in a concise way, but also is sufficient and well suited for classification of non-stationary echo data from objects with different property.The feature extraction is derived from the Discrete Dyadic Wavlet Transform (DDWT) of the echo through the undecimated algorithm. The motivation we use the DDWT is that it is time-shift-invariant which is beneficial for localization of edge, and the wavelet coefficients at larger scale represent the main shape feature of echo, i.e. edge, and the noise and modulated high-frequency components are reduced with scale increased. Some experimental results using real data which contain 144 samples from 4 classes of lake bottoms with different sediments are provided. The results show that our approach is a prospective way to represent wideband echo for reliable recognition of nonstationary echo with great variability. 展开更多
关键词 MALLAT IEEE SP Application of wavelet transform in feature extraction and pattern recognition of wideband echoes
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Regeneration pattern analysis of Quercus liaotungensis in a temperate forest using two-dimensional wavelet analysis
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作者 Xiangcheng MI Jihua HOU 《Frontiers in Biology》 CSCD 2009年第4期491-502,共12页
This paper introduces the two-dimensional(2D)wavelet analysis as a general interrogative technique for the detection of spatial structure in lattice data.The 2D wavelet analysis detects components of hierarchical stru... This paper introduces the two-dimensional(2D)wavelet analysis as a general interrogative technique for the detection of spatial structure in lattice data.The 2D wavelet analysis detects components of hierarchical structure and displays the locational information of the components.Patches and gaps of different spatial scales in graphical presentation of wavelet coefficients can be linked to the local ecological processes that determine patterns at stand or landscape scales.Derived from the 2D wavelet transform function,the calculation of wavelet variance can reduce the four-dimensional data of wavelet coefficients to a two-dimensional wavelet variance function and quantify the contribution of the given scale to the overall pattern.We illustrate the use of the 2D wavelet analysis by analyzing two simulated patterns and identifying the regeneration pattern of the Quercus liaotungensis in a warm temperate forest in north China.Our results indicate that the recruitment of Q.liaotungensis occurs in an overlapping area between the patch of adult and canopy gap at scales of 45m×45m–70m×70m and 20m×20m–30m×30m.The regeneration pattern of Q.liaotungensis can be mainly ascribed to a trade-off between two ecological processes:recruitment around parent trees and the physiological light requirements of seedlings and saplings.Our results provide a general portrayal of the regeneration pattern for the dispersal-limited and shade-intolerant Quercus species.We find that the two-dimensional wavelet analysis efficiently characterizes the scale-specific pattern of Q.liaotungensis at different life-history stages. 展开更多
关键词 Halo wavelet pattern analysis Quercus liaotungensis REGENERATION scale two-dimensional Mex-ican Hat wavelet two-dimensional wavelet analysis wavelet variance
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An unsupervised pattern recognition methodology based on factor analysis and a genetic-DBSCAN algorithm to infer operational conditions from strain measurements in structural applications 被引量:5
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作者 Juan Carlos PERAFAN-LOPEZ Julian SIERRA-PEREZ 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第2期165-181,共17页
Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for ope... Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) algorithm.The methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%. 展开更多
关键词 CLUSTERING DBSCAN Factor analysis FBGs pattern recognition Strain field
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Finger crease pattern recognition using Legendre moments and principal component analysis 被引量:2
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作者 罗荣芳 林土胜 《Chinese Optics Letters》 SCIE EI CAS CSCD 2007年第3期160-163,共4页
The finger joint lines defined as finger creases and its distribution can identify a person. In this paper, we propose a new finger crease pattern recognition method based on Legendre moments and principal component a... The finger joint lines defined as finger creases and its distribution can identify a person. In this paper, we propose a new finger crease pattern recognition method based on Legendre moments and principal component analysis (PCA). After obtaining the region of interest (ROI) for each finger image in the pre- processing stage, Legendre moments under Radon transform are applied to construct a moment feature matrix from the ROI, which greatly decreases the dimensionality of ROI and can represent principal components of the finger creases quite well. Then, an approach to finger crease pattern recognition is designed based on Karhunen-Loeve (K-L) transform. The method applies PCA to a moment feature matrix rather than the original image matrix to achieve the feature vector. The proposed method has been tested on a database of 824 images from 103 individuals using the nearest neighbor classifier. The accuracy up to 98.584% has been obtained when using 4 samples per class for training. The experimental results demonstrate that our proposed approach is feasible and effective in biometrics. 展开更多
关键词 BIOMETRICS Database systems Feature extraction Mathematical transformations pattern recognition Principal component analysis
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Pattern recognition of surface electromyography signal based on wavelet coefficient entropy 被引量:2
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作者 Xiao Hu Ying Gao Wai-Xi Liu 《Health》 2009年第2期121-126,共6页
This paper introduced a novel, simple and ef-fective method to extract the general feature of two surface EMG (electromyography) signal patterns: forearm supination (FS) surface EMG signal and forearm pronation (FP) s... This paper introduced a novel, simple and ef-fective method to extract the general feature of two surface EMG (electromyography) signal patterns: forearm supination (FS) surface EMG signal and forearm pronation (FP) surface EMG signal. After surface EMG (SEMG) signal was decomposed to the fourth resolution level with wavelet packet transform (WPT), its whole scaling space (with frequencies in the interval (0Hz, 500Hz]) was divided into16 frequency bands (FB). Then wavelet coefficient entropy (WCE) of every FB was calculated and corre-spondingly marked with WCE(n) (from the nth FB, n=1,2,…16). Lastly, some WCE(n) were chosen to form WCE feature vector, which was used to distinguish FS surface EMG signals from FP surface EMG signals. The result showed that the WCE feather vector consisted of WCE(7) (187.25Hz, 218.75Hz) and WCE(8) (218.75Hz, 250Hz) can more effectively recog-nize FS and FP patterns than other WCE feature vector or the WPT feature vector which was gained by the combination of WPT and principal components analysis. 展开更多
关键词 Surface EMG Signal wavelet PACKET TRANSFORM ENTROPY pattern recognition
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Performance evaluation of high frequency sub-bands of wavelet transform for palmprint recognition 被引量:1
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作者 张铠麟 张延强 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第6期115-123,共9页
Wavelet decomposition has been applied in palmprint recognition successfully. However, only the low frequency sub-band was used for further feature extraction, while the high frequency sub-bands were considered to be ... Wavelet decomposition has been applied in palmprint recognition successfully. However, only the low frequency sub-band was used for further feature extraction, while the high frequency sub-bands were considered to be unsuitable for palmprint recognition due to their sensitivity to noise and shape distortion. In this paper, we firstly investigate the performances of all the sub-bands by using principal component analysis (PCA) on the BJTU and PolyU palmprint databases, and then use mean filtering to enhance the robustness of the high frequency sub-bands. We find that the preprocessed high frequency sub-bands not only can be used for palmprint recognition but also contain complementary information with the low frequency sub-band. The experimental results show that the performances of the horizontal and vertical high frequency sub-bands can be promoted up to a competitive level, and the fusion scheme, which combines the matching scores of high frequency sub-bands with that of low frequency sub-band, is superior to the conventional recognition methods. 展开更多
关键词 计算机 模式识别 图像识别 声音识别
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A Pattern Recognition Framework for Detecting Changes in Chinese Internet Management System 被引量:1
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作者 Yu-Sung Su Yanqin Ruan +1 位作者 Siyu Sun Yu-tzung Chang 《Journal of Social Computing》 2020年第1期28-39,共12页
Past studies on the Chinese internet management system have revealed a smart internet management system that takes advantage of time to filter content with collective action potential.How and why such a system was ins... Past studies on the Chinese internet management system have revealed a smart internet management system that takes advantage of time to filter content with collective action potential.How and why such a system was institutionalized?We offer a historical institutional analysis to explain the way in which the system evolved.We implement social network analysis to examine the Weibo posts of recurrent events,the elections in Area A in 2016 and 2018,to identify pattern changes in the system.There are two aspects of the changes:the centralization of the command line to a single authority and the implementation of a discriminatory strategy to deal with the various online expressions together forming this intelligent system.The improved Chinese information surveillance system demonstrates both a top-down information management and a bottom-up opinion formation. 展开更多
关键词 internet censorship devolution paradox pattern recognition social network analysis
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Modelling Animal Activity as Curves: An Approach Using Wavelet-Based Functional Data Analysis
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作者 Barbara Henning Airton Kist +4 位作者 Alusio Pinheiro Rafael L. Camargo Thiago M. Batista Everardo M. Carneiro Sérgio F. dos Reis 《Open Journal of Statistics》 2017年第2期203-215,共13页
Temporal activity patterns in animals emerge from complex interactions between choices made by organisms as responses to biotic interactions and challenges posed by external factors. Temporal activity pattern is an in... Temporal activity patterns in animals emerge from complex interactions between choices made by organisms as responses to biotic interactions and challenges posed by external factors. Temporal activity pattern is an inherently continuous process, even being recorded as a time series. The discreteness of the data set is clearly due to data-acquisition limitations rather than a true underlying discrete nature of the phenomenon itself. Therefore, curves are a natural representation for high-frequency data. Here, we fully model temporal activity data as curves integrating wavelets and functional data analysis, allowing for testing hypotheses based on curves rather than on scalar and vector-valued data. Temporal activity data were obtained experimentally for males and females of a small-bodied marsupial and modelled as wavelets with independent and identically distributed errors and dependent errors. The null hypothesis of no difference in temporal activity pattern between male and female curves was tested with functional analysis of variance (FANOVA). The null hypothesis was rejected by FANOVA and we discussed the differences in temporal activity pattern curves between males and females in terms of ecological and life-history attributes of the reference species. We also performed numerical analysis that shed light on the regularity properties of the wavelet bases used and the thresholding parameters. 展开更多
关键词 Functional analysis of Variance HIGH-FREQUENCY Data TEMPORAL Activity pattern SHRINKAGE wavelet THRESHOLDING
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Novel Face Recognition Method by Combining Spatial Domain and Selected Complex Wavelet Features 被引量:1
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作者 张强 蔡云泽 许晓鸣 《Journal of Donghua University(English Edition)》 EI CAS 2011年第3期285-290,共6页
A novel face recognition method based on fusion of spatial and frequency features was presented to improve recognition accuracy. Dual-Tree Complex Wavelet Transform derives desirable facial features to cope with the v... A novel face recognition method based on fusion of spatial and frequency features was presented to improve recognition accuracy. Dual-Tree Complex Wavelet Transform derives desirable facial features to cope with the variation due to the illumination and facial expression changes. By adopting spectral regression and complex fusion technologies respectively, two improved neighborhood preserving discriminant analysis feature extraction methods were proposed to capture the face manifold structures and locality discriminatory information. Extensive experiments have been made to compare the recognition performance of the proposed method with some popular dimensionality reduction methods on ORL and Yale face databases. The results verify the effectiveness of the proposed method. 展开更多
关键词 面对识别 保存判别式分析的邻居 光谱回归 复杂熔化 双树的复杂小浪变换 特征选择
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Automatic recognition and quantitative analysis of Ω phases in Al-Cu-Mg-Ag alloy
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作者 刘冰滨 谷艳霞 +1 位作者 刘志义 田小林 《Journal of Central South University》 SCIE EI CAS 2014年第5期1696-1704,共9页
The main methods of the second phase quantitative analysis in current material science researches are manual recognition and extracting by using software such as Image Tool and Nano Measurer.The weaknesses such as hig... The main methods of the second phase quantitative analysis in current material science researches are manual recognition and extracting by using software such as Image Tool and Nano Measurer.The weaknesses such as high labor intensity and low accuracy statistic results exist in these methods.In order to overcome the shortcomings of the current methods,the Ω phase in Al-Cu-Mg-Ag alloy is taken as the research object and an algorithm based on the digital image processing and pattern recognition is proposed and implemented to do the Al alloy TEM(transmission electron microscope)digital images process and recognize and extract the information of the second phase in the result image automatically.The top-hat transformation of the mathematical morphology,as well as several imaging processing technologies has been used in the proposed algorithm.Thereinto,top-hat transformation is used for elimination of asymmetric illumination and doing Multi-layer filtering to segment Ω phase in the TEM image.The testing results are satisfied,which indicate that the Ω phase with unclear boundary or small size can be recognized by using this method.The omission of these two kinds of Ω phase can be avoided or significantly reduced.More Ω phases would be recognized(growing rate minimum to 2% and maximum to 400% in samples),accuracy of recognition and statistics results would be greatly improved by using this method.And the manual error can be eliminated.The procedure recognizing and making quantitative analysis of information in this method is automatically completed by the software.It can process one image,including recognition and quantitative analysis in 30 min,but the manual method such as using Image Tool or Nano Measurer need 2 h or more.The labor intensity is effectively reduced and the working efficiency is greatly improved. 展开更多
关键词 自动识别 定量分析 合金相 数字图像处理 模式识别算法 透射电子显微镜 图像工具 图像处理技术
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Face Recognition by Combining Wavelet Transform and k-Nearest Neighbor 被引量:2
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作者 Yugang Jiang Ping Guo 《通讯和计算机(中英文版)》 2005年第9期50-53,共4页
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Face Recognition Using LDA with Wavelet Transform Approach
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作者 Neeta Nain Akshay Kumar +3 位作者 Amlesh Kumar Mohapatra Ashok Kumar Ratan Das Nemi Chand Singh 《Computer Technology and Application》 2011年第5期401-405,共5页
关键词 人脸识别系统 小波变换方法 LDA 线性判别分析 性能标准 主成分分析 时间复杂性 特征提取
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基于HPLC指纹图谱结合化学模式识别对葡萄醋的质量评价
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作者 戴丽莉 李晓娟 赵翡翠 《新疆医科大学学报》 CAS 2024年第2期275-281,共7页
目的建立葡萄醋中有机酸成分的高效液相(High performance liquid phase,HPLC)指纹图谱,并结合化学模式识别对葡萄醋质量进行评价及为临床应用提供参考。方法采用HPLC法,以甲醇(A)∶0.5%磷酸水溶液(D)=1∶99洗脱,建立葡萄醋指纹图谱,同... 目的建立葡萄醋中有机酸成分的高效液相(High performance liquid phase,HPLC)指纹图谱,并结合化学模式识别对葡萄醋质量进行评价及为临床应用提供参考。方法采用HPLC法,以甲醇(A)∶0.5%磷酸水溶液(D)=1∶99洗脱,建立葡萄醋指纹图谱,同时测定琥珀酸的含量;采用相似度评价、聚类分析(Cluster analysis,CA)、主成分分析(Principal component analysis,PCA)和偏最小二乘-判别分析(Partial least squares discriminant analysis,PLS-DA)等化学模式识别对差异性特征成分进行筛选。结果15批葡萄醋样品的指纹图谱共有峰有11个,通过与混合对照品色谱峰进行比对,指认出6个共有峰,分别是酒石酸(1号峰),苹果酸(2号峰),琥珀酸(3号峰),富马酸(4号峰),绿原酸(9号峰),乙酸(11号峰);CA结果表明15批葡萄醋样品中各个化合物之间含量差异较大,即使是同一生产企业生产的不同批次葡萄醋其含量差异也较大;PCA结果显示葡萄醋共有峰含量差异的主要成分并非单一成分,而是前4种主成分共同的影响;PLS-DA结果表明筛选出的7、3、9、4号峰可作为鉴别和区分葡萄醋质量差异的标志物,其中包括共有峰3号峰(琥珀酸)、4号峰(富马酸)。结论采用指纹图谱结合化学模式识别技术可快速、有效地筛选出葡萄醋的差异性特征成分,为葡萄醋质量评价及临床应用提供参考。 展开更多
关键词 葡萄醋 指纹图谱 聚类分析 主成分分析 化学模式识别
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