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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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A biorthogonality relationship for three-dimensional couple stress problem 被引量:8
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作者 LUO JianHui LI QiuSheng LIU GuangDong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2009年第2期270-276,共7页
The duality solution for elasticity and the biorthogonality relationship have been well researched. Now the couple stress theory becomes a new research spot but there is few research for the biorthogonality relationsh... The duality solution for elasticity and the biorthogonality relationship have been well researched. Now the couple stress theory becomes a new research spot but there is few research for the biorthogonality relationship for couple stress theory comparing to classical elasticity. A new state vector is presented for three dimensional couple stress problems of prismatic structures. A new biorthogonality relation- ship of couple stress is discovered. The dual partial differential equations of couple stress problem are derived by the new state vector. By two important identical equations the new biorthogonality rela- tionship is proved based on the method of separation of variables. The symplectic orthogonality rela- tionship to three dimensional couple stress theory may be decomposed into two independently and symmetrically orthogonality relationships. The new biorthogonality relationship includes the symplec- tic orthogonality relationship. The biorthogonality relationship of couple stress may also be degener- ated into the theory of elasticity. The new state vector and biorthogonality relationship provide theo- retic foundation for the research on the schemes of separation of variables and eigenfunction expan- sion of couple stress theory. 展开更多
关键词 COUPLE STRESS DUALITY solution biorthogonality RELATIONSHIP HAMILTONIAN state space
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Representation of three-dimensional mass distribution of the Earth's interior by biorthogonal series and its use for studying internal structure of the planet
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作者 Mykhailo Fys Mariana Yurkiv +1 位作者 Andrii Brydun Andrii Sohor 《Geodesy and Geodynamics》 EI CSCD 2024年第3期264-275,共12页
This paper utilizes the mathematical concept of approximation within an ellipsoid from a single viewpoint to present the spatial mass distribution function of the Earth's interior and its internal potential.The pr... This paper utilizes the mathematical concept of approximation within an ellipsoid from a single viewpoint to present the spatial mass distribution function of the Earth's interior and its internal potential.The primary focus lies in constructing the volume distribution of masses in the planet's interior, with the expansion coefficients being linear combinations of the Stokes constants. Several possible approaches are suggested for determining accurately these coefficients employing three-dimensional(biorthogonal)polynomials. By expressing the mass distribution function of the Earth's interior and its internal potential as a series, an algorithm is introduced for the calculation of gravitational energy. It allows us to estimate fluctuations in gravitational energy. The implementation of this algorithm offers the means of establishing the extent to which the Earth deviates from a state of hydrostatic equilibrium as a celestial body.Due to the aforementioned method, calculations have been conducted to validate its effectiveness and reliability. This example is given as an illustration of a given method for studying the internal structure of planets. 展开更多
关键词 Mass distribution function Potential Stokes constants Biorthogonal polynomials
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Super-Fast Approximation Algorithms Using Classical Fourier Tools
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作者 Anry Nersessian 《Advances in Pure Mathematics》 2024年第7期596-618,共23页
In the author’s recent publications, a parametric system biorthogonal to the corresponding segment of the exponential Fourier system was unusually effective. On its basis, it was discovered that knowledge of a finite... In the author’s recent publications, a parametric system biorthogonal to the corresponding segment of the exponential Fourier system was unusually effective. On its basis, it was discovered that knowledge of a finite number of Fourier coefficients of function f from an infinite-dimensional set of elementary functions allows f to be accurately restored (the phenomenon of over-convergence). Below, parametric biorthogonal systems are constructed for classical trigonometric Fourier series, and the corresponding phenomena of over-convergence are discovered. The decisive role here was played by representing the space L2 as an orthogonal sum of two corresponding subspaces. As a result, fast parallel algorithms for reconstructing a function from its truncated trigonometric Fourier series are proposed. The presented numerical experiments confirm the high efficiency of these convergence accelerations for smooth functions. In conclusion, the main results of the work are summarized, and some prospects for the development and generalization of the proposed approaches are discussed. 展开更多
关键词 Fourier Series Acceleration of Convergence Parametric Biorthogonalization Spectral Methods Over-Convergence Phenomenon
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小波基在低压电力线信道有色背景噪声建模中的应用研究 被引量:12
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作者 索超男 张慧 赵雄文 《电力系统保护与控制》 EI CSCD 北大核心 2017年第4期121-125,共5页
小波马尔科夫链法可用于低压电力线信道中有色背景噪声的建模,但小波基函数的不同会对噪声的建模精度产生较大影响。基于常用的几种小波基函数对同一组有色背景噪声分别开展小波马尔科夫链仿真建模,并计算了建模前后的功率谱密度及其均... 小波马尔科夫链法可用于低压电力线信道中有色背景噪声的建模,但小波基函数的不同会对噪声的建模精度产生较大影响。基于常用的几种小波基函数对同一组有色背景噪声分别开展小波马尔科夫链仿真建模,并计算了建模前后的功率谱密度及其均方根误差。研究结果表明,Daubecies、Biorthogonal和Haar小波基函数中Daubecies小波基函数的建模精度较高,Haar小波基次之,Biorthogonal小波的建模效果较差。在这3种小波基函数中,Daubecies小波可选为有色背景噪声进行小波马尔科夫链建模的最佳小波基函数。 展开更多
关键词 小波马尔科夫链 有色背景噪声 小波基函数 Biorthogonal小波 Daubecies小波 HAAR小波
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Seismic data compression based on integer wavelet transform 被引量:1
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作者 WANG Xi-zhen(王喜珍) +5 位作者 TENG Yun-tian(滕云田) GAO Meng-tan(高孟潭) JIANG Hui(姜慧) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第z1期123-128,共6页
Due to the particularity of the seismic data, they must be treated by lossless compression algorithm in some cases. In the paper, based on the integer wavelet transform, the lossless compression algorithm is studied.... Due to the particularity of the seismic data, they must be treated by lossless compression algorithm in some cases. In the paper, based on the integer wavelet transform, the lossless compression algorithm is studied. Comparing with the traditional algorithm, it can better improve the compression rate. CDF (2, n) biorthogonal wavelet family can lead to better compression ratio than other CDF family, SWE and CRF, which is owe to its capability in can- celing data redundancies and focusing data characteristics. CDF (2, n) family is suitable as the wavelet function of the lossless compression seismic data. 展开更多
关键词 lossless compression integer wavelet transform lifting scheme biorthogonal wavelet
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Wavelet Adaptive Bitzerotree Coding for Video
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作者 衡伟 富煜清 +1 位作者 韦志辉 程时昕 《Journal of Southeast University(English Edition)》 EI CAS 1997年第2期34-38,共5页
WaveletAdaptiveBitzerotreeCodingforVideoHengWei(衡伟)FuYuqing(富煜清)WeiZhihui(韦志辉)ChengShixing(程时昕)(Departmentof... WaveletAdaptiveBitzerotreeCodingforVideoHengWei(衡伟)FuYuqing(富煜清)WeiZhihui(韦志辉)ChengShixing(程时昕)(DepartmentofRadioEngineering,... 展开更多
关键词 WAVELET analysis BIORTHOGONAL WAVELET ZEROTREE VIDEO CODING MULTIRESOLUTION decomposition
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The Boundary Processing of Wavelet Based Image Compression
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作者 YuSheng-sheng HeXiao-cheng ZhouJing-li ChenJia-zhong 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第3期296-302,共7页
When an image, which is decomposed by bi-orthogonal wavelet bases, is reconstructed, some information will be lost at the four edges of the image. At the same time, artificial discontinuities will be introduced. We us... When an image, which is decomposed by bi-orthogonal wavelet bases, is reconstructed, some information will be lost at the four edges of the image. At the same time, artificial discontinuities will be introduced. We use a method called symmetric extension to solve the problem. We only consider the case of the two-band filter banks, and the results can be applied to M-band filter banks. There are only two types of symmetric extension in analysis phrase, namely the whole-sample symmetry (WS), the half-sample symmetry (HS), while there are four types of symmetric extension in synthesis phrase, namely the WS, HS, the whole-sample anti-symmetry (WA), and the half-sample anti-symmetry (HA) respectively. We can select the exact type according to the image length and the filter length, and we will show how to do these. The image can be perfectly reconstructed without any edge effects in this way. Finally, simulation results are reported. Key words edge effect - image compression - wavelet - biorthogonal bases - symmetric extension CLC number TP 37 Foundation item: Supported by the National 863 Project (20021111901010)Biography: Yu Sheng-sheng (1944-), male, Professor, research direction: multimedia information processing, SAN. 展开更多
关键词 edge effect image compression WAVELET biorthogonal bases symmetric extension
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HYPERCYCLIC OPERATORS ON QUASI-MAZUR SPACES
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作者 丘京辉 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1709-1720,共12页
Modifying the method of Ansari, we give some criteria for hypercyclicity of quasi-Mazur spaces. They can be applied to judging hypercyclicity of non-complete and non-metrizable locally convex spaces. For some special ... Modifying the method of Ansari, we give some criteria for hypercyclicity of quasi-Mazur spaces. They can be applied to judging hypercyclicity of non-complete and non-metrizable locally convex spaces. For some special locally convex spaces, for example, KSthe (LF)-sequence spaces and countable inductive limits of quasi-Mazur spaces, we investigate their hypercyclicity. As we see, bounded biorthogonal systems play an important role in the construction of Ansari. Moreover, we obtain characteristic conditions respectively for locally convex spaces having bounded sequences with dense linear spans and for locally convex spaces having bounded absorbing sets, which are useful in judging the existence of bounded biorthogonal systems. 展开更多
关键词 hypercyclic operator bounded biorthogonal systems quasi-Mazur space inductive limit Kothe (LF)-sequence space
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Singularity Detecting with the SecondGeneration Wavelet
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作者 XU Bing-lian 1,2 , YI Xu-ming 1 1.School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei, China 2.College of Science,Nanjing Agriculture University,Nanjing 210095,Jingsu,China 《Wuhan University Journal of Natural Sciences》 CAS 2004年第6期871-874,共4页
Adopting the lifting scheme, introduced by Sweldens, a new wavelet is constructed. It overcomes the shortcoming of the classical wavelets that has no flexibility in the number of vanishing moment. Two examples are giv... Adopting the lifting scheme, introduced by Sweldens, a new wavelet is constructed. It overcomes the shortcoming of the classical wavelets that has no flexibility in the number of vanishing moment. Two examples are given to prove the second-generation wavelets's potentialities in the singularity detection of signal: a wavelet with vanishing moment and symmetry can be constructed according to the problem. Key words biorthogonal wavelet - lifting scheme - secondgeneration wavelets - singularity CLC number O 174.2 Foundation item: Supported by the National Natural Science Foundation of China (19602014)Biography: XU Bing-lian (1977-), female, Master candidate, research direction: the wavelets application. 展开更多
关键词 biorthogonal wavelet lifting scheme secondgeneration wavelets SINGULARITY
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FREQUENCY OPTIMIZATION APPROACH FOR DESIGNING M-BAND BIORTHOGONAL SYMMETRIC WAVELETS
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作者 WangJianwei ZhangZeyin HuangDaren 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第2期193-199,共7页
In this paper,a new method is presented for designing M-band biorthogonal symmetric wavelets.The design problem of biorthogonal linear-phase scaling filters and wavelet filters as a quadratic programming problem with ... In this paper,a new method is presented for designing M-band biorthogonal symmetric wavelets.The design problem of biorthogonal linear-phase scaling filters and wavelet filters as a quadratic programming problem with the linear constraints is formulated.The closed-form solution is given and a design example is presented. 展开更多
关键词 linear-phase M-band biorthogonal wavelets quadratic programming.
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Methods of Constructing Optimal Wavelet Filters Based on Genetic Algorithm
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作者 Wen Gao-jin, Quan Hui-yunCollege of Mathematics and Computer, Hunan Normal University, Changsha 410081, Hunan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期279-282,共4页
In this paper, algorithms of constructing wavelet filters based on genetic algorithm are studied with emphasis on how to construct the optimal wavelet filters used to compress a given image, due to efficient coding of... In this paper, algorithms of constructing wavelet filters based on genetic algorithm are studied with emphasis on how to construct the optimal wavelet filters used to compress a given image, due to efficient coding of the chromosome and the fitness function, and due to the global optimization algorithm, this method turns out to be perfect for the compression of the images. 展开更多
关键词 biorthogonal wavelet genetic algorithm OPTIMAL
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P wave onset time picking with the B-spline biorthogonal wavelet
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作者 滕云田 王喜珍 +2 位作者 王晓美 马洁美 许建华 《Acta Seismologica Sinica(English Edition)》 CSCD 2006年第3期350-355,共6页
The seismic wave consists of many seismic phases, which contain rich geophysical information from the hypocenter, medium of seismic wave passing through and so on. It is very important to detect and pick these seismic... The seismic wave consists of many seismic phases, which contain rich geophysical information from the hypocenter, medium of seismic wave passing through and so on. It is very important to detect and pick these seismic phases for understanding the mechanism of earthquake, the Earth structure and property of seismic waves. In order to reduce or avoid the loss resulted from the earthquake, one of the important goals of seismic event detecting is to obtain its related information before and after it occurs. Because of the particularity of P wave and S wave the seismic event detecting focuses on distinguishing P and S waves and picking their onset time, it has been becoming one of the research hotspots for many geophysicists to pick the P and S wave arrival accurately and effectively. 展开更多
关键词 biorthogonal wavelet characteristic function the onset time picking
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Performance Evaluation of Wavelet Based on Human Visual System
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作者 胡海平 莫玉龙 《Journal of Shanghai University(English Edition)》 CAS 2002年第3期216-220,共5页
We have constructed a compactly supported biorthogonal wavelet that approximates the modulation transfer function (MTF) of human visual system in the frequency domain. In this paper, we evaluate performance of the con... We have constructed a compactly supported biorthogonal wavelet that approximates the modulation transfer function (MTF) of human visual system in the frequency domain. In this paper, we evaluate performance of the constructed wavelet, and compare it with the widely used Daubechies 9 7, Daubechies 9 3 and GBCW 9 7 wavelets. The result shows that coding performance of the constructed wavelet is better than Daubechies 9 3, and is competitive with Daubechies 9 7 and GBCW 9 7 wavelets. Like Daubechies 9 3 wavelet, the filter coefficients of the constructed wavelet are all dyadic fractions, and the tap is less than Daubechies 9 7 and GBCW 9 7. It has an attractive feature in the realization of discrete wavelet transform. 展开更多
关键词 biorthogonal wavelet REGULARITY peak to peak ratio weighted subband coding gain.
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On the Zeros of Daubechies Orthogonal and Biorthogonal Wavelets
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作者 Jalal Karam 《Applied Mathematics》 2012年第7期778-787,共10页
In the last decade, Daubechies’ wavelets have been successfully used in many signal processing paradigms. The construction of these wavelets via two channel perfect reconstruction filter bank requires the identificat... In the last decade, Daubechies’ wavelets have been successfully used in many signal processing paradigms. The construction of these wavelets via two channel perfect reconstruction filter bank requires the identification of necessary conditions that the coefficients of the filters and the roots of binomial polynomials associated with them should exhibit. In this paper, orthogonal and Biorthogonal Daubechies families of wavelets are considered and their filters are derived. In particular, the Biorthogonal wavelets Bior3.5, Bior3.9 and Bior6.8 are examined and the zeros distribution of their polynomials associated filters are located. We also examine the locations of these zeros of the filters associated with the two orthogonal wavelets db6 and db8. 展开更多
关键词 ORTHOGONAL BIORTHOGONAL WAVELETS BINOMIAL POLYNOMIALS
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Adaptive Biorthogonal Local Discrete Cosine Transform for Interference Excision in Direct Sequence Spread Spectrum Communications
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作者 朱丽平 胡光锐 朱义胜 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期139-142,共4页
A novel time-frequency domain interference excision technique is proposed. The technique is based on adaptive biorthogonal local discrete cosine trans form (BLDCT). It uses a redundant library of biorthogonal local d... A novel time-frequency domain interference excision technique is proposed. The technique is based on adaptive biorthogonal local discrete cosine trans form (BLDCT). It uses a redundant library of biorthogonal local discrete cosine bases and an efficient concave cost function to match the transform basis to the interfering signal. The main advantage of the algorithm over conventional trans form domain excision algorithms is that the basis functions are not fixed but ca n be adapted to the time-frequency structure of the interfering signal. It is w e ll suited to transform domain compression and suppression of various types of in terference. Compared to the discrete wavelet transform (DWT) that provides logar ithmic division of the frequency bands, the adaptive BLDCT can provide more flex ible frequency resolution. Thus it is more insensitive to variations of jamming frequency. Simulation results demonstrate the improved bit error rate (BER) perf ormance and the increased robustness of the receiver. 展开更多
关键词 biorthogonal local discrete cosine transform (BLDCT) interference excision spr ead spectrum communications.
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Modulated Lapped Biorthogonal Transform for Non-orthogonal Narrowband Interference Excision in Spread Spectrum Communications
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作者 朱丽平 胡光锐 +1 位作者 赵海波 朱义胜 《Journal of Shanghai University(English Edition)》 CAS 2005年第3期237-240,共4页
Traditional lapped transform domain excision techniques obtain good performance at the expense of increased processing delay. Extension of transform domain filtering techniques to the lapped biorthogonal transform dom... Traditional lapped transform domain excision techniques obtain good performance at the expense of increased processing delay. Extension of transform domain filtering techniques to the lapped biorthogonal transform domain can help solve the problem. By incorporating biorthogonality into the lapped transforms, more flexibility is obtained in the design of windows. Thus transform bases with better stopband attenuation can be generated by designing windows, but not by increasing the overlapping factor. In this paper, a new modulated lapped biorthogonal transform (MLBT) with optimized windows is introduced for efficient compression of multi-tone interfering signal energy. The bit error rate (BER) performance of the receiver employing the proposed MLBT excision technique is analyzed and compared with that of the lapped transform domain excision-based receivers. Simulation results demonstrate the improved performance and increased robustness of the proposed technique. 展开更多
关键词 modulated lapped biorthogonal transform (MLBT) narrowband interference excision spread spectrum communications.
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A General Algorithm for Biorthogonal Functions and Performance Analysis of Biorthogonal Scramble Modulation System
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作者 Yueyun Chen Zhenhui Tan 《Wireless Sensor Network》 2010年第3期199-205,共7页
Applying the theorems of Mobius inverse and Dirichlet inverse, a general algorithm to obtain biorthogonal functions based on generalized Fourier series analysis is introduced. In the algorithm, the orthogonal function... Applying the theorems of Mobius inverse and Dirichlet inverse, a general algorithm to obtain biorthogonal functions based on generalized Fourier series analysis is introduced. In the algorithm, the orthogonal function can be not only Fourier or Legendre series, but also can be any one of all orthogonal function systems. These kinds of biorthogonal function sets are used as scramble signals to construct biorthogonal scramble modulation (BOSM) wireless transmission systems. In a BOSM system, the transmitted signal has significant security performance. Several different BOSM and orthogonal systems are compared on aspects of BER performance and spectrum efficiency, simulation results show that the BOSM systems based on Chebyshev polynomial and Legendre polynomial are better than BOSM system based on Fourier series, also better than orthogonal MCM and OFDM systems. 展开更多
关键词 BIORTHOGONAL FUNCTIONS BIORTHOGONAL SCRAMBLE Modulation Generalized FOURIER Series MOBIUS INVERSE Wireless Transmission
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Tracking of Non-Rigid Object in Complex Wavelet Domain
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作者 Om Prakash Ashish Khare 《Journal of Signal and Information Processing》 2011年第2期105-111,共7页
In this paper we have proposed an object tracking method using Dual Tree Complex Wavelet Transform (DTCxWT). The proposed method is capable of tracking the moving object in video sequences. The object is assumed to be... In this paper we have proposed an object tracking method using Dual Tree Complex Wavelet Transform (DTCxWT). The proposed method is capable of tracking the moving object in video sequences. The object is assumed to be deform-able under limit i.e. it may change its shape from one frame to another. The basic idea in the proposed method is to decompose the image into two components: a two dimensional motion and a two dimensional shape change. The motion component is factored out while the shape is explicitly represented by storing a sequence of two dimensional models. Each model corresponds to each image frame. The proposed method performs well when the change in the shape in the consecutive frames is small however the 2-D motion in consecutive frames may be large. The proposed algorithm is capable of handling the partial as well as full occlusion of the object. 展开更多
关键词 Object TRACKING Dual TREE Complex WAVELET TRANSFORM Model Based TRACKING BIORTHOGONAL FILTERS
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A Wavelet Multigrid Method Using Symmetric Biorthogonal Wavelets
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作者 Doreen De Leon 《American Journal of Computational Mathematics》 2013年第2期127-136,共10页
In [1], the author introduced a wavelet multigrid method that used the wavelet transform to define the coarse grid, interpolation, and restriction operators for the multigrid method. In this paper, we modify the metho... In [1], the author introduced a wavelet multigrid method that used the wavelet transform to define the coarse grid, interpolation, and restriction operators for the multigrid method. In this paper, we modify the method by using symmetric biorthogonal wavelet transforms to define the requisite operators. Numerical examples are presented to demonstrate the effectiveness of the modified wavelet multigrid method for diffusion problems with highly oscillatory coefficients, as well as for advection-diffusion equations in which the advection is moderately dominant. 展开更多
关键词 MULTIGRID WAVELETS BIORTHOGONAL WAVELETS
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