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Application of multi-resolution analysis in sonar image denoising 被引量:1
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作者 Shang Zhengguo Zhao Chunhui Wan Jian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1082-1089,共8页
Sonar images have complex background, low contrast, and deteriorative edges; these characteristics make it difficult for researchers to dispose the sonar objects. The multi-resolution analysis represents the signals i... Sonar images have complex background, low contrast, and deteriorative edges; these characteristics make it difficult for researchers to dispose the sonar objects. The multi-resolution analysis represents the signals in different scales efficiently, which is widely used in image processing. Wavelets are successful in disposing point discontinuities in one dimension, but not in two dimensions. The finite Ridgelet transform (FRIT) deals efficiently with the singularity in high dimension. It presents three improved denoising approaches, which are based on FRIT and used in the sonar image disposal technique. By experiment and comparison with traditional methods, these approaches not only suppress the artifacts, but also obtain good effect in edge keeping and SNR of the sonar image denoising. 展开更多
关键词 multi-resolution analysis wavelet transform ridgelet transform cycle sample adaptive denoisingenergy delamination
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Multi-Resolution Fourier Analysis Part I: Fundamentals
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作者 Nourédine Yahya Bey 《International Journal of Communications, Network and System Sciences》 2011年第6期364-371,共8页
In the first paper of this series, we propose a multi-resolution theory of Fourier spectral estimates of finite duration signals. It is shown that multi-resolution capability, achieved without further observation, is ... In the first paper of this series, we propose a multi-resolution theory of Fourier spectral estimates of finite duration signals. It is shown that multi-resolution capability, achieved without further observation, is obtained by constructing multi-resolution signals from the only observed finite duration signal. Achieved resolutions meet bounds of the uncertainty principle (Heisenberg inequality). In the forthcoming parts of this series, multi-resolution Fourier performances are observed, applied to short signals and extended to time-frequency analysis. 展开更多
关键词 multi-resolution SPECTRAL analysis FOURIER analysis RESOLUTION Frequency RESOLUTION
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Analysis on electric energy measuring method based on multi-resolution analysis
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作者 张晓冰 崔家瑞 +1 位作者 梁原华 王慕坤 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第2期193-195,共3页
Along with the massive applications of the non-linear loads and the impact loads, many non-stationary stochastic signals such as harmonics, inter-harmonics, impulse signals and so on are introduced into the electric n... Along with the massive applications of the non-linear loads and the impact loads, many non-stationary stochastic signals such as harmonics, inter-harmonics, impulse signals and so on are introduced into the electric network, and these non-stationary stochastic signals have had effects on the accuracy of the measurement of electric energy. The traditional method like Fourier Analysis can he applied efficiently on the stationary stochastic signals, hut it has little effect on non-stationary stochastic signals. In light of this, the form of the signals of the electric network in wavelet domain will he discussed in this paper. A measurement method of active power based on multi-resolution analysis in the stochastic process is presented. This method has a wider application scope compared with the traditional method Fourier analysis, and it is of good referential value and practical value in terms of raising the level of the existing electric energy measurement. 展开更多
关键词 electric energy measurement multi-resolution analysis active power
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Fault Feature Extraction of Rotating Machinery Based on Wavelet Transformation and Multi-resolution Analysis
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作者 公茂法 刘庆雪 +1 位作者 刘明 张晓丽 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期312-314,共3页
This paper expounded in detail the principle of energy spectrum analysis based on discrete wavelet transformation and multiresolution analysis. In the aspect of feature extraction method study, with investigating the ... This paper expounded in detail the principle of energy spectrum analysis based on discrete wavelet transformation and multiresolution analysis. In the aspect of feature extraction method study, with investigating the feature of impact factor in vibration signals and considering the non-placidity and non-linear of vibration diagnosis signals, the authors import wavelet analysis and fractal theory as the tools of faulty signal feature description. Experimental results proved the validity of this method. To some extent, this method provides a good approach of resolving the wholesome problem of fault feature symptom description. 展开更多
关键词 discrete wavelet transform (DWT) multi-resolution analysis fault diagnosis rotating madchinery feature extraction
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Multi-Resolution Fourier Analysis Part II: Missing Signal Recovery and Observation Results
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作者 Nourédine Yahya Bey 《International Journal of Communications, Network and System Sciences》 2012年第1期28-36,共9页
In this paper, we report application procedures and observed results of multi-resolution Fourier analysis proposed in the first part of this series. Missing signal recovery derived from multi-resolution theory is deve... In this paper, we report application procedures and observed results of multi-resolution Fourier analysis proposed in the first part of this series. Missing signal recovery derived from multi-resolution theory is developed. It is shown that multi-resolution Fourier analysis enhances dramatically performances of Fourier spectra suffering limitations traced to implicit time windowing. Observed frequency resolutions, improvement of frequency estimations, contraction of spectral leakage and recovery of missing parts of finite duration signals are in accordance with theoretical predictions. 展开更多
关键词 FOURIER multi-resolution SPECTRAL analysis FREQUENCY Estimation FREQUENCY Resolution SPECTRAL LEAKAGE MISSING Parts Signal Recovery
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Vector-intensity measure based seismic vulnerability analysis of bridge structures 被引量:8
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作者 Li Zhongxian Li Yang Li Ning 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第4期695-705,共11页
This paper presents a method for seismic vulnerability analysis of bridge structures based on vector-valued intensity measure (viM), which predicts the limit-state capacities efficiently with multi-intensity measure... This paper presents a method for seismic vulnerability analysis of bridge structures based on vector-valued intensity measure (viM), which predicts the limit-state capacities efficiently with multi-intensity measures of seismic event. Accounting for the uncertainties of the bridge model, ten single-bent overpass bridge structures are taken as samples statistically using Latin hypercube sampling approach. 200 earthquake records are chosen randomly for the uncertainties of ground motions according to the site condition of the bridges. The uncertainties of structural capacity and seismic demand are evaluated with the ratios of demand to capacity in different damage state. By comparing the relative importance of different intensity measures, Sa(T1) and Sa(T2) are chosen as viM. Then, the vector-valued fragility functions of different bridge components are developed. Finally, the system-level vulnerability of the bridge based on viM is studied with Duunett- Sobel class correlation matrix which can consider the correlation effects of different bridge components. The study indicates that an increment IMs from a scalar IM to viM results in a significant reduction in the dispersion of fragility functions and in the uncertainties in evaluating earthquake risk. The feasibility and validity of the proposed vulnerability analysis method is validated and the bridge is more vulnerable than any components. 展开更多
关键词 bridge structure seismic vulnerability analysis vector-valued intensity measure components' correlation system vulnerability
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MULTI-RESOLUTION MOTION ESTIMATION AND COMPENSATION BASED ON ADJACENT PREDICTION OF FRAME DIFFERENCE IN WAVELET DOMAIN 被引量:3
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作者 Tang Guowei Gu Guochang 《Journal of Electronics(China)》 2009年第3期412-416,共5页
Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame... Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame difference was proposed.Differential motion detection was employed to image sequences and proper threshold was adopted to identify the connected region.Then the motion region was extracted to carry out motion estimation and motion compensation on it.The experiment results show that the encoding efficiency of motion vector is promoted, the complexity of motion estimation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Resolution Motion Estimation(MRME) is improved. 展开更多
关键词 Wavelet transforms Motion estimation Motion compensation multi-resolution analysis Video coding
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Construction of Orthogonal Vector-valued Wavelets and Characteristics of Vector-valued Wavelet Packets 被引量:1
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作者 CHEN Qing-jiang LIU Hong-yun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期360-367,共8页
The notion of vector-valued multiresolution analysis is introduced and the concept of orthogonal vector-valued wavelets with 3-scale is proposed. A necessary and sufficient condition on the existence of orthogonal vec... The notion of vector-valued multiresolution analysis is introduced and the concept of orthogonal vector-valued wavelets with 3-scale is proposed. A necessary and sufficient condition on the existence of orthogonal vector-valued wavelets is given by means of paraunitary vector filter bank theory. An algorithm for constructing a class of compactly supported orthogonal vector-valued wavelets is presented. Their characteristics is discussed by virtue of operator theory, time-frequency method. Moreover, it is shown how to design various orthonormal bases of space L^2(R, C^n) from these wavelet packets. 展开更多
关键词 ORTHOGONAL Hermitian matrix vector-valued multiresolution analysis vector-valued scaling functions vector-valued wavelets vector-valued wavelet packets
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h-ADAPTIVE ANALYSIS BASED ON MESHLESS LOCAL PETROV-G ALERKIN METHOD WITH B SPLINE WAVELET FOR PLATES AND SHELLS 被引量:1
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作者 Di Li Zhongqin Lin 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第4期337-346,共10页
Using the two-scale decomposition technique, the h-adaptive meshless local Petrov- Galerkin method for solving Mindlin plate and shell problems is presented. The scaling functions of B spline wavelet are employed as t... Using the two-scale decomposition technique, the h-adaptive meshless local Petrov- Galerkin method for solving Mindlin plate and shell problems is presented. The scaling functions of B spline wavelet are employed as the basis of the moving least square method to construct the meshless interpolation function. Multi-resolution analysis is used to decompose the field variables into high and low scales and the high scale component can commonly represent the gradient of the solution according to inherent characteristics of wavelets. The high scale component in the present method can directly detect high gradient regions of the field variables. The developed adaptive refinement scheme has been applied to simulate actual examples, and the effectiveness of the present adaptive refinement scheme has been verified. 展开更多
关键词 meshless methods meshless local Petrov-Galerkin method multi-resolution analysis adaptive analysis plate and shell
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Multi-resolution EMD and classscatter matrix extracting of tank sound 被引量:1
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作者 张万君 吴晓颖 王新 《Journal of Beijing Institute of Technology》 EI CAS 2012年第1期91-95,共5页
The acoustic vibration signal of tank is disassembled into the sum of intrinsic mode function (IMF) by multi-resolution empirical mode decomposition (EMD) method. The instantaneous frequency is obtained, and featu... The acoustic vibration signal of tank is disassembled into the sum of intrinsic mode function (IMF) by multi-resolution empirical mode decomposition (EMD) method. The instantaneous frequency is obtained, and feature transformation matrix is figured out by class scatter matrix. Multi- dimensional scale energy vector is mapped into low-dimensional eigenvector, and classification extraction is realized. This method sufficiently separates of different sound target features. The test result indicates that it is effective. 展开更多
关键词 multi-resolution analysis EMD method sound feature extraction class scatter matrix
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Characterizations of Orthogonal Vector-valued Multivariate Wavelet Packets
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作者 HUA De-lin FENG Jin-shun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期606-614,共9页
In this paper, the notion of orthogonal vector-valued wavelet packets of space L2 (R^s, C^n) is introduced. A procedure for constructing the orthogonal vector-valued wavelet packets is presented. Their properties ar... In this paper, the notion of orthogonal vector-valued wavelet packets of space L2 (R^s, C^n) is introduced. A procedure for constructing the orthogonal vector-valued wavelet packets is presented. Their properties are characterized by virtue of time-frequency analysis method, matrix theory and finite group theory, and three orthogonality formulas are obtained. Finally, new orthonormal bases of space L2(R^s,C^n) are extracted from these wavelet packets. 展开更多
关键词 ORTHOGONALITY refinement equation vector-valued multiresolution analysis vector-valued scaling function vector-valued wavelet packets
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The Biorthogonality of Multiple Vector-valued Bivariate Wavelet Packets
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作者 CHEN Shao-dong HUANG Na 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第2期208-213,共6页
The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavel... The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavelet packets in higher dimensions is studied by means of Fourier transform and integral transform biorthogonality formulas concerning these wavelet packets are obtained. 展开更多
关键词 BIVARIATE multiple vector-valued multiresolution analysis multiple vectorvalued scaling function multiple vector-valued wavelet packets biorthogonality
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Online Test and Fault Diagnosis of Yarn Quality Using Wavelet Analysis and FFT
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作者 洪锡军 邱浩波 +1 位作者 李昱明 李从心 《Journal of Donghua University(English Edition)》 EI CAS 2002年第2期99-102,共4页
A new online system of monitoring yarn quality and fault diagnosis is presented. This system integrates the technologies of sensor, signal process, communication, network, computer, control, instrument structure and m... A new online system of monitoring yarn quality and fault diagnosis is presented. This system integrates the technologies of sensor, signal process, communication, network, computer, control, instrument structure and mass knowledge of experts. Comparing with conventional off-line yarn test, the new system can find the quality defects of yarn online in time and compensate for the lack of expert knowledge in manual analysis. It can save a lot of yarn wasted in off-line test and improve product quality. By using laser sensor to sample the diameter signal of yarn and doing wavelet analysis and FFT to extract fault characteristics, a set of reasoning mechanism is established to analyze yarn quality and locate the fault origination. The experimental results show that new system can do well in monitoring yarn quality online comparing with conventional off-line yarn test. It can test the quality of yarn in real-time with high efficiency and analyze the fault reason accurately. It is very useful to apply this new system to upgrade yarn quality in cotton textile industry at present. 展开更多
关键词 WAVELET Transform multi-resolution analysis FFT FAULT Diagnosis ONLINE Test
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Conformal Wavelet Finite-difference Time-domain Algorithm for Analysis of Milimeter Wave Attenuation on Coplanar Waveguide
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作者 DAI Hong-quan CHEN Hai-yan 《Semiconductor Photonics and Technology》 CAS 2007年第3期206-209,共4页
Addressed is the calculation of millimeter wave attenuation on coplanar waveguide(CPW). A novel conformal wavelet finite-difference time-domain(CWFDTD) algorithm is proposed with emphasis on its application in calcula... Addressed is the calculation of millimeter wave attenuation on coplanar waveguide(CPW). A novel conformal wavelet finite-difference time-domain(CWFDTD) algorithm is proposed with emphasis on its application in calculation of millimeter wave attenuation on CPW, which is the combination of conformal algorithm dealing with the deformed cell with Wavelet-FDTD using multi-resolution analysis(MRA). Derived is the difference formulation for multi-resolution time domain(MRTD) based on Daubechies wavelets, and also given is the stability conditions for wavelet-FDTD algorithm. To validate its accuracy and efficiency, this novel method is applied to calculate the millimeter wave attenuation on lithium niobate CPW. Numerical results demonstrate that this new CWFDTD algorithm has the same accuracy with the conformal finite-difference time-domain(CFDTD) and conformal finite-difference time-domain based on alternating-direction implicit method(ADI-CFDTD), but saves computational time and computer memory. 展开更多
关键词 millimeter wave attenuation conformal wavelet FDTD algorithm multi-resolution analysis multi-resolution time domain coplanar waveguide
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Wavelet Transform for Image Compression Using Multi-Resolution Analytics: Application to Wireless Sensors Data
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作者 Wasiu Opeyemi Oduola Cajetan M. Akujuobi 《Advances in Pure Mathematics》 2017年第8期430-440,共11页
The aggregation of data in recent years has been expanding at an exponential rate. There are various data generating sources that are responsible for such a tremendous data growth rate. Some of the data origins includ... The aggregation of data in recent years has been expanding at an exponential rate. There are various data generating sources that are responsible for such a tremendous data growth rate. Some of the data origins include data from the various social media, footages from video cameras, wireless and wired sensor network measurements, data from the stock markets and other financial transaction data, supermarket transaction data and so on. The aforementioned data may be high dimensional and big in Volume, Value, Velocity, Variety, and Veracity. Hence one of the crucial challenges is the storage, processing and extraction of relevant information from the data. In the special case of image data, the technique of image compressions may be employed in reducing the dimension and volume of the data to ensure it is convenient for processing and analysis. In this work, we examine a proof-of-concept multiresolution analytics that uses wavelet transforms, that is one popular mathematical and analytical framework employed in signal processing and representations, and we study its applications to the area of compressing image data in wireless sensor networks. The proposed approach consists of the applications of wavelet transforms, threshold detections, quantization data encoding and ultimately apply the inverse transforms. The work specifically focuses on multi-resolution analysis with wavelet transforms by comparing 3 wavelets at the 5 decomposition levels. Simulation results are provided to demonstrate the effectiveness of the methodology. 展开更多
关键词 WAVELETS multi-resolution analysis Image Compressions WIRELESS Sensor Networks MATHEMATICAL DATA ANALYTICS
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MULTI-RESOLUTION LEAST SQUARES SUPPORT VECTOR MACHINES
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作者 Wang Liejun Zhang Taiyi Zhou Yatong 《Journal of Electronics(China)》 2007年第5期701-704,共4页
The Least Squares Support Vector Machines (LS-SVM) is an improvement to the SVM. Combined the LS-SVM with the Multi-Resolution Analysis (MRA),this letter proposes the Multi-resolution LS-SVM (MLS-SVM).The proposed alg... The Least Squares Support Vector Machines (LS-SVM) is an improvement to the SVM. Combined the LS-SVM with the Multi-Resolution Analysis (MRA),this letter proposes the Multi-resolution LS-SVM (MLS-SVM).The proposed algorithm has the same theoretical framework as MRA but with better approximation ability.At a fixed scale MLS-SVM is a classical LS-SVM,but MLS-SVM can gradually approximate the target function at different scales.In experiments,the MLS-SVM is used for nonlinear system identification,and achieves better identification accuracy. 展开更多
关键词 Support Vector Machines (SVM) Least square method multi-resolution analysis (MRA) Nonlinear system identification
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Multi-resolution Analysis of Density Fluctuation of Coherent Structures About Supersonic Flow over VG 被引量:2
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作者 WANG Dengpan ZHAO Yuxin +2 位作者 XIA Zhixun WANG Qinghua HUANG Xu 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2012年第2期173-181,共9页
The density field around a vortex generator (VG) in supersonic flow is studied with a nanoparticle-based planar laser scattering (NPLS) method. Based on the calibration, i.e., the density distribution of the super... The density field around a vortex generator (VG) in supersonic flow is studied with a nanoparticle-based planar laser scattering (NPLS) method. Based on the calibration, i.e., the density distribution of the supersonic flow around a wedge, the density field of a supersonic VG is measured. According to movement characteristics of coherent structure in VG’s flow fields and the basic concepts of wavelet, the density fluctuating signals and multi-resolution characteristics of density field images are studied. The multi-resolution characteristics of density fluctuation can be analyzed with wavelet transformation of NPLS images. The wavelet approximate coefficients of density fluctuating signals exhibit their characteristics at different scales, and the corresponding detail coefficients show the difference of diverse layer smooth approximation in some way. Based on 2D wavelet decomposition and reconstruction of density field images, the approximate and detail signals at different scales are studied, and the coherent structures at different scales are extracted and analyzed. 展开更多
关键词 vortex generator nanoparticle-based planar laser scattering coherent structure density fluctuation multi-resolution analysis
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A RECTANGULAR SHELL ELEMENT FORMULATION WITH A NEW MULTI-RESOLUTION ANALYSIS 被引量:2
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作者 Yiming Xia Yuanxue Liu +1 位作者 Shaolin Chen Gan Tang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2014年第6期612-625,共14页
A multi-resolution rectangular shell element with membrane-bending based on the Kirchhoff-Love theory is proposed. The multi-resolution analysis (MRA) framework is formulated out of a mutually nesting displacement s... A multi-resolution rectangular shell element with membrane-bending based on the Kirchhoff-Love theory is proposed. The multi-resolution analysis (MRA) framework is formulated out of a mutually nesting displacement subspace sequence, whose basis functions are constructed of scaling and shifting on the element domain of basic node shape functions. The basic node shape functions are constructed from shifting to other three quadrants around a specific node of a basic element in one quadrant and joining the corresponding node shape functions of four elements at the specific node. The MRA endows the proposed element with the resolution level (RL) to adjust the element node number, thus modulating structural analysis accuracy accordingly. The node shape functions of Kronecker delta property make the treatment of element boundary condition quite convenient and enable the stiffness matrix and the loading column vectors of the proposed element to be automatically acquired through quadraturing around nodes in RL adjusting. As a result, the traditional 4-node rectangular shell element is a mono-resolution one and also a special case of the proposed element. The accuracy of a structural analysis is actually determined by the RL, not by the mesh. The simplicity and clarity of node shape function formulation with the Kronecker delta property, and the rational MRA enable the proposed element method to be implemented more rationally, easily and efficiently than the conventional mono-resolution rectangular shell element method or other corresponding MRA methods. 展开更多
关键词 rectangular shell element multi-resolution analysis (MRA) resolution level (RL) basic node shape function mutually nesting displacement subspace sequence scaling and shifting
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Orthogonal Multiple Vector-Valued Wavelet Packets 被引量:3
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作者 陈清江 程正兴 李学志 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2007年第2期289-297,共9页
The multiple vector-valued wavelet packets are defined and investigated. A procedure for constructing the multiple vector-valued wavelet packets is presented. The properties of multiple vector-valued wavelet packets a... The multiple vector-valued wavelet packets are defined and investigated. A procedure for constructing the multiple vector-valued wavelet packets is presented. The properties of multiple vector-valued wavelet packets are discussed by using integral transformation and operator theory. Finally, new orthogonal bases of L^2(R, C^s×s) is constructed from the orthogonal multiple vector-valued wavelet packets. 展开更多
关键词 vector-valued multiresolution analysis multiple vector-valued scaling functions multiple vector-valued wavelet packets refinement equation.
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A Quotient Space Approximation Model of Multiresolution Signal Analysis 被引量:19
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作者 LingZhang BoZhang 《Journal of Computer Science & Technology》 SCIE EI CSCD 2005年第1期90-94,共5页
In this paper, we present a quotient space approximation model of multiresolution signal analysis and discuss the properties and characteristics of the model. Then the comparison between wavelet transform and the quot... In this paper, we present a quotient space approximation model of multiresolution signal analysis and discuss the properties and characteristics of the model. Then the comparison between wavelet transform and the quotient space approximation is made. First, when wavelet transform is viewed from the new quotient space approximation perspective, it may help us to gain an insight into the essence of multiresolution signal analysis. Second, from the similarity between wavelet and quotient space approximations, it is possible to transfer the rich wavelet techniques into the latter so that a new way for multiresolution analysis may be found. 展开更多
关键词 multi-resolution signal analysis wavelet transform quotient space the second-generation wavelets
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