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K-L变换观测矩阵优化算法 被引量:2
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作者 王海艳 佟岐 +1 位作者 连志鹏 汲清波 《计算机工程与应用》 CSCD 北大核心 2018年第19期186-190,215,共6页
观测矩阵的研究在压缩感知中尤为重要,其中观测矩阵的优化是观测矩阵研究中的关键问题之一。根据减小观测矩阵与稀疏矩阵之间的互相关性达到优化观测矩阵的思想,提出了K-L变换观测矩阵优化算法。该算法利用原始信号协方差矩阵的特征向... 观测矩阵的研究在压缩感知中尤为重要,其中观测矩阵的优化是观测矩阵研究中的关键问题之一。根据减小观测矩阵与稀疏矩阵之间的互相关性达到优化观测矩阵的思想,提出了K-L变换观测矩阵优化算法。该算法利用原始信号协方差矩阵的特征向量矩阵对传感矩阵进行变换,从而减小观测矩阵与稀疏矩阵之间的互相关性,进而得到优化后的观测矩阵。仿真结果表明,优化后的观测矩阵重构图像的峰值信噪比值大于未优化观测矩阵重构图像的峰值信噪比值,尤其是在观测数目较少的情况下,用该算法优化后的观测矩阵重构的图像具有较高的精度。 展开更多
关键词 压缩感知 观测矩阵 karhunen-loeve(k-l)变换 协方差矩阵 互相关性
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License Plate Recognition Based on Transform Coding and Neural Network
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作者 李小平 胡海生 +2 位作者 宋瀚涛 朱建学 丁俨 《Journal of Beijing Institute of Technology》 EI CAS 2003年第1期42-45,共4页
A method of vehicle license plate recognition utilizing Karhunen-Loeve(K-L) transform is provided. The transform is used to extract features from a mass of image templates, to describe high-dimensional images with low... A method of vehicle license plate recognition utilizing Karhunen-Loeve(K-L) transform is provided. The transform is used to extract features from a mass of image templates, to describe high-dimensional images with low-dimensional ones, and moreover, to implement data compression and play down complexity of the neural network. With the character to reduce eigenspace dimensionality of K-L transform and the ability to map data of BP network, the method does effectively in recognizing license plates. 展开更多
关键词 k-l transform BP network pattern recognition
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混凝土单轴受压本构关系的概率密度描述 被引量:4
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作者 曾莎洁 李杰 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第6期798-804,共7页
利用混凝土材料的细观随机损伤物理模型获取混凝土应力—应变关系的概率密度描述.以细观物理模型为基础,利用K-L(Karhunen-Loeve)正交分解和密度演化方法得到了单轴受力状态任意应变处应力的概率密度函数估计.将数值计算结果与试验结果... 利用混凝土材料的细观随机损伤物理模型获取混凝土应力—应变关系的概率密度描述.以细观物理模型为基础,利用K-L(Karhunen-Loeve)正交分解和密度演化方法得到了单轴受力状态任意应变处应力的概率密度函数估计.将数值计算结果与试验结果进行概率密度层次的对比.研究证实:可以采用这一方法描述混凝土受力本构关系的概率密度演化过程. 展开更多
关键词 混凝土 随机损伤演化 k-l(karhunen-loeve)分解 密度演化方法
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Ultrasonic signal classification based on ambiguity plane feature 被引量:4
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作者 Du Xiuli Wang Yan Shen Yi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期427-433,共7页
Ambiguity function (AF) is proposed to represent ultrasonic signal to resolve the preprocessing problem of different center frequencies and different arriving times among ultrasonic signals for feature extraction, a... Ambiguity function (AF) is proposed to represent ultrasonic signal to resolve the preprocessing problem of different center frequencies and different arriving times among ultrasonic signals for feature extraction, as well as offer time-frequency features for signal classification. Moreover, Karhunen-Loeve (K-L) transform is considered to extract signal features from ambiguity plane, and then the features are presented to probabilistic neural network (PNN) for signal classification. Experimental results show that ambiguity function eliminates the difference of center frequency and arriving time existing in ultrasonic signals, and ambiguity plane features extracted by K-L transform describe the signal of different classes effectively in a reduced dimensional space. Classification result suggests that the ambiguity plane features obtain better performance than the features extracted by wavelet transform (WT). 展开更多
关键词 ultrasonic testing signal classification ambiguity function k-l transform
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A New Method for Correcting Vehicle License Plate Tilt 被引量:2
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作者 Mei-Sen Pan Qi Xiong Jun-Biao Yan 《International Journal of Automation and computing》 EI 2009年第2期210-216,共7页
In the course of vehicle license plate (VLP) automatic recognition, tilt correction is a very crucial process. According to Karhunen-Loeve (K-L) transformation, the coordinates of characters in the image are arran... In the course of vehicle license plate (VLP) automatic recognition, tilt correction is a very crucial process. According to Karhunen-Loeve (K-L) transformation, the coordinates of characters in the image are arranged into a two-dimensional covariance matrix, on the basis of which the centered process is carried out. Then, the eigenvector and the rotation angle α are computed in turn. The whole image is rotated by -α. Thus, image horizontal tilt correction is performed. In the vertical tilt correction process, three correction methods, which are K-L transformation method, the line fitting method based on K -means clustering (LFMBKC), and the line fitting based on least squares (LFMBLS), are put forward to compute the vertical tilt angle θ. After shear transformation (ST) is imposed on the rotated image, the final correction image is obtained. The experimental results verify that this proposed method can be easily implemented, and can quickly and accurately get the tilt angle. It provides a new effective way for the VLP image tilt correction as well. 展开更多
关键词 Tilt correction k-l transformation projection profile Hough transformation.
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Neural network approach to blindestimation of PN spreading sequence in lower SNR DS/SS signals 被引量:6
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作者 Zhang Tianqi Lin Xiaokang Zhou Zhengzhong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期756-760,共5页
An approach based on discrete Karhunen-Loeve transformation of the DS/SS signals is proposed to estimate PN sequence in lower S/N ratio DS/SS signals. Characteristics of self-organization and principle components extr... An approach based on discrete Karhunen-Loeve transformation of the DS/SS signals is proposed to estimate PN sequence in lower S/N ratio DS/SS signals. Characteristics of self-organization and principle components extraction of unsupervised neural networks are exploited adequately. Theoretical analysis and experimental results are provided to show that this approach can work well on the lower S/N ratio input signals. 展开更多
关键词 discrete karhunen-loeve transformation neural networks direct sequence spread spectrum (DS/SS) signal PN sequence.
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FEATURE ANALYSIS AND EXTRACTION OF INNER DEFECTS FOR SPOT WELD NUGGET OF ALUMINUM ALLOY 被引量:1
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作者 Gang, Tie Shen, Chunlong Gong, Runli 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第3期130-134,共5页
1INTRODUCTIONSpotweldinghasbeenwidelyusedinaluminumaloystructuresofspacecraftandaircraftduetoitscharacteris... 1INTRODUCTIONSpotweldinghasbeenwidelyusedinaluminumaloystructuresofspacecraftandaircraftduetoitscharacteristicsoftechnology.... 展开更多
关键词 SPOT welding NUGGET defect k-l transformation FEATURE ANALYSIS
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Research and Implementation of a License Plate Recognition Algorithm Based on Hierarchical Classification 被引量:2
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作者 Haofei Gao Wanrong Sun +1 位作者 Xinran Liu Ming Han 《Journal of Computer and Communications》 2014年第2期25-30,共6页
This paper proposed an improved method for license plate recognition based on hierarchical classification. First, the method of feature extraction and dimension reduction is presented by finding the optimal wavelet pa... This paper proposed an improved method for license plate recognition based on hierarchical classification. First, the method of feature extraction and dimension reduction is presented by finding the optimal wavelet packet basis in the process of wavelet packet decomposition and K-L transform. Then the recognition algorithm is introduced based on feature extraction and hierarchical classification. Finally, the principles and procedures of using support vector machines, Harris corner detection algorithm and digital character classification are explained in detail. Simulation results indicate that the presented recognition algorithm performs well with higher speed and efficiency in recognition. 展开更多
关键词 WAVELET PACKET k-l transform SVM Recognition LICENSE Plate
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A multispectral image compression and encryption algorithm based on tensor decomposition and chaos 被引量:1
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作者 XU Dongdong DU Limin 《High Technology Letters》 EI CAS 2022年第2期134-141,共8页
A multi spectral image compression and encryption algorithm that combines Karhunen-Loeve(KL) transform,tensor decomposition and chaos is proposed for solving the security problem of multi-spectral image compression an... A multi spectral image compression and encryption algorithm that combines Karhunen-Loeve(KL) transform,tensor decomposition and chaos is proposed for solving the security problem of multi-spectral image compression and transmission.Firstly,in order to eliminate residual spatial redundancy and most of the spectral redundancy,the image is performed by KL transform.Secondly,to further eliminate spatial redundancy and reduce block effects in the compression process,two-dimensional discrete 9/7 wavelet transform is performed,and then Arnold transform and encryption processing on the transformed coefficients are performed.Subsequently,the tensor is decomposed to keep its intrinsic structure intact and eliminate residual space redundancy.Finally,differential pulse filters are used to encode the coefficients,and Tent mapping is used to implement confusion diffusion encryption on the code stream.The experimental results show that the method has high signal-to-noise ratio,fast calculation speed,and large key space,and it is sensitive to keys and plaintexts with a positive effect in spectrum assurance at the same time. 展开更多
关键词 karhunen-loeve(KL)transform tensor decomposition differential pulse filter Tent map
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KLT-based local linear prediction of chaotic time series
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作者 Meng Qingfang Peng Yuhua Chen Yuehui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期694-699,共6页
In the reconstructed phase space, based on the Karhunen-Loeve transformation (KLT), the new local linear prediction method is proposed to predict chaotic time series. & noise-free chaotic time series and a noise ad... In the reconstructed phase space, based on the Karhunen-Loeve transformation (KLT), the new local linear prediction method is proposed to predict chaotic time series. & noise-free chaotic time series and a noise added chaotic time series are analyzed. The simulation results show that the KLT-based local linear prediction method can effectively make one-step and multi-step prediction for chaotic time series, and the one-step and multi-step prediction accuracies of the KLT-based local linear prediction method are superior to that of the traditional local linear prediction. 展开更多
关键词 karhunen-loeve transformation local linear prediction phase space reconstruction chaotic time series.
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An infrared human face recognition method based on 2DPCA
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作者 刘侠 李廷军 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期265-268,共4页
Aimed at the problems of infrared image recognition under varying illumination,face disguise,etc.,we bring out an infrared human face recognition algorithm based on 2DPCA.The proposed algorithm can work out the covari... Aimed at the problems of infrared image recognition under varying illumination,face disguise,etc.,we bring out an infrared human face recognition algorithm based on 2DPCA.The proposed algorithm can work out the covariance matrix of the training sample easily and directly;at the same time,it costs less time to work out the eigenvector.Relevant experiments are carried out,and the result indicates that compared with the traditional recognition algorithm,the proposed recognition method is swift and has a good adaptability to the changes of human face posture. 展开更多
关键词 infrared image face recognition feature sub-space k-l transformation
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Application of ambiguity function to ultrasonic signal recognition
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作者 杜秀丽 沈毅 王艳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第5期608-612,共5页
The ambiguity function (AF) is proposed to represent the ultrasonic signal for its modulus’ independence of time shift and frequency shift, which avoids the effect of center frequency and arriving time of the ultraso... The ambiguity function (AF) is proposed to represent the ultrasonic signal for its modulus’ independence of time shift and frequency shift, which avoids the effect of center frequency and arriving time of the ultrasonic signal on feature extraction. Moreover, the K-L transform is considered to extract features from the ambiguity plane, and the effect of signals to noises on validity of ambiguity features is analyzed. Furthermore, we discuss the performance of recognizing ultrasonic signals at different center frequencies and different arriving time based on ambiguity features. Experimental results show that the features extracted by the K-L transform (KLT) are immune to noises, and can recognize ultrasonic signals effectively in a lower dimensional space. 展开更多
关键词 ambiguity function k-l transform ultrasonic testing signal recognition
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A reversibility-gain model for integer Karhunen-Loève transform design in video coding
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作者 Xing-guo ZHU Lu YU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2015年第10期883-891,共9页
Karhunen-Loeve transform (KLT) is the optimal transform that minimizes distortion at a given bit allocation for Gaussian source. As a KLT matrix usually contains non-integers, integer-KLT design is a classical probl... Karhunen-Loeve transform (KLT) is the optimal transform that minimizes distortion at a given bit allocation for Gaussian source. As a KLT matrix usually contains non-integers, integer-KLT design is a classical problem. In this paper, a joint reversibility-gain (R-G) model is proposed for integer-KLT design in video coding. Specifically, the 'reversibility' is modeled according to distortion analysis in using forward and inverse integer transform without quantization. It not only measures how invcrtible a transform is, but also bounds the distortion introduced by the non-orthonormal integer transform process. The 'gain' means transform coding gain (TCG), which is a widely used criterion for transform design in video coding. Since KLT maximizes the TCG under some assumptions, here we define the TCG loss ratio (LR) to measure how much coding gain an integer-KLT loses when compared with the original KLT. Thus, the R-G model can be explained as follows: subject to a certain TCG LR, an integer- KLT with the best reversibility is the optimal integer transform for a given non-integer-KLT. Experimental results show that the R-G model can guide the design of integer-KLTs with good performance. 展开更多
关键词 Integer transform karhunen-loeve transform (KLT) Integer-KLT transform coding Video coding
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