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An Efficient Numerical Scheme for Biological Models in the Frame of Bernoulli Wavelets 被引量:1
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作者 Fei Li Haci Mehmet Baskonus +3 位作者 S.Kumbinarasaiah G.Manohara Wei Gao Esin Ilhan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2381-2408,共28页
This article considers three types of biological systems:the dengue fever disease model,the COVID-19 virus model,and the transmission of Tuberculosis model.The new technique of creating the integration matrix for the ... This article considers three types of biological systems:the dengue fever disease model,the COVID-19 virus model,and the transmission of Tuberculosis model.The new technique of creating the integration matrix for the Bernoulli wavelets is applied.Also,the novel method proposed in this paper is called the Bernoulli wavelet collocation scheme(BWCM).All three models are in the form system of coupled ordinary differential equations without an exact solution.These systems are converted into a system of algebraic equations using the Bernoulli wavelet collocation scheme.The numerical wave distributions of these governing models are obtained by solving the algebraic equations via the Newton-Raphson method.The results obtained from the developed strategy are compared to several schemes such as the Runge Kutta method,and ND solver in mathematical software.The convergence analyses are discussed through theorems.The newly implemented Bernoulli wavelet method improves the accuracy and converges when it is compared with the existing methods in the literature. 展开更多
关键词 Biological systems system of coupled ODEs bernoulli wavelets functional matrix collocation technique
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ASTER Data Processing by Discrete Wavelets Transform and Band Ratio Techniques for the Identification of Lineaments and Hydrothermal Alteration Zones in Poli, North Cameroon
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作者 Mohamadou Ahamadou May Nome Stella Meying Arsène 《Journal of Geoscience and Environment Protection》 2023年第9期216-232,共17页
The aim of this study is to carry out hydrothermal alteration mapping and structural mapping using ASTER images in order to identify indices that could guide mining exploration work in the Poli area and its surroundin... The aim of this study is to carry out hydrothermal alteration mapping and structural mapping using ASTER images in order to identify indices that could guide mining exploration work in the Poli area and its surroundings. To achieve this, the ASTER images were first preprocessed to correct atmospheric effects and remove vegetation influence. Secondly, a lineament mapping was conducted by applying Discrete Wavelet Transform (DWT) algorithms to the First Principal Component Analysis (PCA1) of Visible Near-Infrared (VNIR) and Shortwave Infrared (SWIR) bands. Lastly, band ratio methods were applied to the VNIR, SWIR, and Thermal Infrared (TIR) bands to determine indices of iron oxides/hydroxides (hematite and limonite), hydroxyl-bearing minerals (chlorite, epidote, and muscovite), and the quartz index. The results obtained showed that the lineaments were mainly oriented NE-SW, ENE-WSW, and E-W, with NE-SW being the most predominant direction. Concerning hydrothermal alteration, the identified indices covered almost the entire study area and showed a strong correlation with lithological data. Overlaying the obtained lineaments with the hydrothermal alteration indices revealed a significant correlation between existing mining indices and those observed in the field. Mineralized zones generally coincided with areas of high lineament density exhibiting significant hydrothermal alteration. Based on the correlation between existing mining indices and the results of hydrothermal and structural mapping, the results obtained can then be used as a reference document for any mining exploration in the study area. 展开更多
关键词 Discrete wavelets Transform Band Ratio LINEAMENTS Hydrothermal Alteration
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A CLASS OF MULTIWAVELETS AND PROJECTED FRAMES FROM TWO-DIRECTION WAVELETS 被引量:3
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作者 李尤发 杨守志 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期285-300,共16页
This article aims at studying two-direction refinable functions and two-direction wavelets in the setting R^s, s 〉 1. We give a sufficient condition for a two-direction refinable function belonging to L^2(R^s). The... This article aims at studying two-direction refinable functions and two-direction wavelets in the setting R^s, s 〉 1. We give a sufficient condition for a two-direction refinable function belonging to L^2(R^s). Then, two theorems are given for constructing biorthogonal (orthogonal) two-direction refinable functions in L^2(R^s) and their biorthogonal (orthogonal) two-direction wavelets, respectively. From the constructed biorthogonal (orthogonal) two-direction wavelets, symmetric biorthogonal (orthogonal) multiwaveles in L^2(R^s) can be obtained easily. Applying the projection method to biorthogonal (orthogonal) two-direction wavelets in L^2(R^s), we can get dual (tight) two-direction wavelet frames in L^2(R^m), where m ≤ s. From the projected dual (tight) two-direction wavelet frames in L^2(R^m), symmetric dual (tight) frames in L^2(R^m) can be obtained easily. In the end, an example is given to illustrate theoretical results. 展开更多
关键词 Two-direction refinable functions two-direction wavelets MULTIwavelets waveletframes biothogonal (orthogonal) SYMMETRY projection method
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A Method for Solving Fredholm Integral Equations of the First Kind Based on Chebyshev Wavelets 被引量:2
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作者 M. Bahmanpour M. A.Fariborzi Araghi 《Analysis in Theory and Applications》 2013年第3期197-207,共11页
In this paper, we suggest a method for solving Fredholm integral equation of the first kind based on wavelet basis. The continuous Legendre and Chebyshev wavelets of the first, second, third and fourth kind on [0,1] a... In this paper, we suggest a method for solving Fredholm integral equation of the first kind based on wavelet basis. The continuous Legendre and Chebyshev wavelets of the first, second, third and fourth kind on [0,1] are used and are utilized as a basis in Galerkin method to approximate the solution of integral equations. Then, in some examples the mentioned wavelets are compared with each other. 展开更多
关键词 First kind Fredholm integral equation Galerkin and Modified Galerkin method Legendre wavelets Chebyshev wavelets.
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Some Generalized q-Bessel Type Wavelets and Associated Transforms
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作者 Imen Rezgui Anouar Ben Mabrouk 《Analysis in Theory and Applications》 CSCD 2018年第1期57-76,共20页
In this paper wavelet functions are introduced in the context of q-theory. We precisely extend the case of Bessel and q-Bessel wavelets to the generalized q-Bessel wavelets. Starting from the (q,v)-extension (v = ... In this paper wavelet functions are introduced in the context of q-theory. We precisely extend the case of Bessel and q-Bessel wavelets to the generalized q-Bessel wavelets. Starting from the (q,v)-extension (v = (α,β)) of the q-case, associated generalized q-wavelets and generalized q-wavelet transforms are developed for the new context. Reconstruction and Placherel type formulas are proved. 展开更多
关键词 wavelets Besel function q-Bessel function modified Bessel functions generalizedq-Bessel functions q-Bessel wavelets.
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CONSTRUCTION OF COMPACTLY SUPPORTED BIVARIATE ORTHOGONAL WAVELETS BY UNIVARIATE ORTHOGONAL WAVELETS 被引量:4
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作者 杨建伟 李落清 唐远炎 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期233-242,共10页
After some permutation of conjugate quadrature filter, new conjugate quadrature filters can be derived. In terms of this permutation, an approach is developed for constructing compactly supported bivariate orthogonal ... After some permutation of conjugate quadrature filter, new conjugate quadrature filters can be derived. In terms of this permutation, an approach is developed for constructing compactly supported bivariate orthogonal wavelets from univariate orthogonal wavelets. Non-separable orthogonal wavelets can be achieved. To demonstrate this method, an example is given. 展开更多
关键词 PERMUTATION non-separable wavelets conjugate quadrature filter
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Synthesis of accelerograms compatible with the Chinese GB 50011-2001 design spectrum via harmonic wavelets: artifi cial and historic records 被引量:3
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作者 P.D. Spanos A. Giaralis Li Jie 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第2期189-206,共18页
A versatile approach is employed to generate artificial accelerograms which satisfy the compatibility criteria prescribed by the Chinese aseismic code provisions GB 50011-2001. In particular, a frequency dependent pea... A versatile approach is employed to generate artificial accelerograms which satisfy the compatibility criteria prescribed by the Chinese aseismic code provisions GB 50011-2001. In particular, a frequency dependent peak factor derived by means of appropriate Monte Carlo analyses is introduced to relate the GB 50011-2001 design spectrum to a parametrically defined evolutionary power spectrum (EPS). Special attention is given to the definition of the frequency content of the EPS in order to accommodate the mathematical form of the aforementioned design spectrum. Further, a one-to-one relationship is established between the parameter controlling the time-varying intensity of the EPS and the effective strong ground motion duration. Subsequently, an efficient auto-regressive moving-average (ARMA) filtering technique is utilized to generate ensembles of non-stationary artificial accelerograms whose average response spectrum is in a close agreement with the considered design spectrum. Furthermore, a harmonic wavelet based iterative scheme is adopted to modify these artificial signals so that a close matching of the signals' response spectra with the GB 50011-2001 design spectrum is achieved on an individual basis. This is also done for field recorded accelerograms pertaining to the May, 2008 Wenchuan seismic event. In the process, zero-phase high-pass filtering is performed to accomplish proper baseline correction of the acquired spectrum compatible artificial and field accelerograms. Numerical results are given in a tabulated format to expedite their use in practice. 展开更多
关键词 design spectrum Chinese aseismic code artificial accelerograms evolutionary power spectrum peak factor recorded accelerograms wavelets
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MULTIRESOLUTION ANALYSIS, SELF-SIMILAR TILINGS AND HAAR WAVELETS ON THE HEISENBERG GROUP 被引量:2
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作者 刘和平 刘宇 王海辉 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1251-1266,共16页
In this article, the properties of multiresolution analysis and self-similar tilings on the Heisenberg group are studied. Moreover, we establish a theory to construct an orthonormal Haar wavelet base in L^2(H^d) by ... In this article, the properties of multiresolution analysis and self-similar tilings on the Heisenberg group are studied. Moreover, we establish a theory to construct an orthonormal Haar wavelet base in L^2(H^d) by using self-similar tilings for the acceptable dilations on the Heisenberg group. 展开更多
关键词 Heisenberg group multiresolution analysis wavelets self-similar tilings
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WAVELETS FROM TRIGONOMETRIC SPLINE APPROACH 被引量:4
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作者 Chen Hanlin (Academia Sinica,China) 《Analysis in Theory and Applications》 1996年第2期99-110,共12页
The explicit form for the orthonormal periodic trigonometric spline wavelet is given. We also give the decomposition and reconstruction equations.Each of the two equations involves onlytwo terms. We prove that the fam... The explicit form for the orthonormal periodic trigonometric spline wavelet is given. We also give the decomposition and reconstruction equations.Each of the two equations involves onlytwo terms. We prove that the family of periodic trigonometric spline wavelets is dense in L2([0,2π]). 展开更多
关键词 wavelets FROM TRIGONOMETRIC SPLINE APPROACH APPI
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Solving the Nonlinear Variable Order Fractional Differential Equations by Using Euler Wavelets 被引量:1
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作者 Yanxin Wang Li Zhu Zhi Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第2期339-350,共12页
An Euler wavelets method is proposed to solve a class of nonlinear variable order fractional differential equations in this paper.The properties of Euler wavelets and their operational matrix together with a family of... An Euler wavelets method is proposed to solve a class of nonlinear variable order fractional differential equations in this paper.The properties of Euler wavelets and their operational matrix together with a family of piecewise functions are first presented.Then they are utilized to reduce the problem to the solution of a nonlinear system of algebraic equations.And the convergence of the Euler wavelets basis is given.The method is computationally attractive and some numerical examples are provided to illustrate its high accuracy. 展开更多
关键词 EULER wavelets variable order FRACTIONAL differential EQUATIONS caputo FRACTIONAL derivatives OPERATIONAL matrix CONVERGENCE analysis.
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Medical Image Compression Based on Wavelets with Particle Swarm Optimization 被引量:1
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作者 Monagi H.Alkinani E.A.Zanaty Sherif M.Ibrahim 《Computers, Materials & Continua》 SCIE EI 2021年第5期1577-1593,共17页
This paper presents a novel method utilizing wavelets with particle swarm optimization(PSO)for medical image compression.Our method utilizes PSO to overcome the wavelets discontinuity which occurs when compressing ima... This paper presents a novel method utilizing wavelets with particle swarm optimization(PSO)for medical image compression.Our method utilizes PSO to overcome the wavelets discontinuity which occurs when compressing images using thresholding.It transfers images into subband details and approximations using a modified Haar wavelet(MHW),and then applies a threshold.PSO is applied for selecting a particle assigned to the threshold values for the subbands.Nine positions assigned to particles values are used to represent population.Every particle updates its position depending on the global best position(gbest)(for all details subband)and local best position(pbest)(for a subband).The fitness value is developed to terminate PSO when the difference between two local best(pbest)successors is smaller than a prescribe value.The experiments are applied on five different medical image types,i.e.,MRI,CT,and X-ray.Results show that the proposed algorithm can be more preferably to compress medical images than other existing wavelets techniques from peak signal to noise ratio(PSNR)and compression ratio(CR)points of views. 展开更多
关键词 Image compression wavelets Haar wavelet particle swarm algorithm medical image compression PSNR and CR
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A CLASS OF COMPACTLY SUPPORTED ORTHOGONAL SYMMETRIC COMPLEX WAVELETS WITH DILATION FACTOR 3 被引量:1
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作者 杨守志 沈延锋 李尤发 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1415-1425,共11页
When approximation order is an odd positive integer, a simple method is given to construct compactly supported orthogonal symmetric complex scaling function with dilation factor 3. Two corresponding orthogonal wavelet... When approximation order is an odd positive integer, a simple method is given to construct compactly supported orthogonal symmetric complex scaling function with dilation factor 3. Two corresponding orthogonal wavelets, one is symmetric and the other is antisymmetric about origin, are constructed explicitly. Additionally, when approximation order is an even integer 2, we also give a method to construct compactly supported orthogonal symmetric complex that illustrate the corresponding results. wavelets. In the end, there are several examples 展开更多
关键词 orthogonal complex wavelets approximation order SYMMETRY scaling function
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The Lifting Scheme Based on the Second Generation Wavelets 被引量:1
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作者 FENG Hui GUO Lanying XIAO Jinsheng 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期503-506,共4页
The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing t... The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing time with its particular frame. This paper aims at introducing the second generation wavelets, begins with traditional Mallat algorithms, illustrates the lifting scheme and brings out the detail steps in the construction of Biorthogonal wavelets. Because of isolating the degrees of freedom remaining the biorthogonality relations, we can fully control over the lifting operators to design the wavelet for a particular application, such as increasing the number of the vanishing moments. 展开更多
关键词 lifting scheme the second generation wavelets vanishing moments
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GENERALIZED WAVELETS AND INVERSION OF THE RADON TRANSFORM ON THE LAGUERRE HYPERGROUP 被引量:1
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作者 Bai Linglan He Jianxun (Nanjing Normal University, China) 《Approximation Theory and Its Applications》 2002年第4期55-69,共15页
Let X=Rn +×R denote the underlying manifold of polyradial functions on the Heisenberg group H n. We construct a generalized translation on X=Rn +×R, and establish the Plancherel formula on L2(X,dμ). Usin... Let X=Rn +×R denote the underlying manifold of polyradial functions on the Heisenberg group H n. We construct a generalized translation on X=Rn +×R, and establish the Plancherel formula on L2(X,dμ). Using the Gelfand transform we give the condition of generalized wavelets on L2(X,dμ). Moreover, we show the reconstruction formulas for wavelet packet trnasforms and an inversion formula of the Radon transform on X. 展开更多
关键词 MATH GENERALIZED wavelets AND INVERSION OF THE RADON TRANSFORM ON THE LAGUERRE HYPERGROUP
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COMPACTLY SUPPORTED BOX-SPLINE WAVELETS 被引量:2
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作者 C.K.Chui J.Stckler J.D.Ward 《Analysis in Theory and Applications》 1992年第3期77-100,共24页
A general procedure for constructing multivariate non-tensor-product wavelets that gen- erate an orthogonal decomposition of L^2(R~),s≥ 1,is described and applied to yield explicit formulas for compactly supported sp... A general procedure for constructing multivariate non-tensor-product wavelets that gen- erate an orthogonal decomposition of L^2(R~),s≥ 1,is described and applied to yield explicit formulas for compactly supported spline-wavelets based on the multiresolution analysis of L^2(R^s),1≤s≤3,generated by any box spline whose direction set constitutes a unimodular matrix.In particular,when univariate cardinal B-splines are considered,the minimally sup- ported cardinal spline-wavelets of Chui and Wang are recovered.A refined computational scheme for the orthogonalization of spaces with compactly supported wavelets is given.A recursive approximation scheme for“truncated”decomposition sequences is developed and a sharp error bound is included.A condition on the symmetry or anti-symmetry of the wavelets is applied to yield symmetric box-spline wavelets. 展开更多
关键词 COMPACTLY SUPPORTED BOX-SPLINE wavelets
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Finite Elements Based on Deslauriers-Dubuc Wavelets for Wave Propagation Problems 被引量:1
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作者 Rodrigo Bird Burgos Marco Antonio Cetale Santos 《Applied Mathematics》 2016年第14期1490-1497,共9页
This paper presents the formulation of finite elements based on Deslauriers-Dubuc interpolating scaling functions, also known as Interpolets, for their use in wave propagation modeling. Unlike other wavelet families l... This paper presents the formulation of finite elements based on Deslauriers-Dubuc interpolating scaling functions, also known as Interpolets, for their use in wave propagation modeling. Unlike other wavelet families like Daubechies, Interpolets possess rational filter coefficients, are smooth, symmetric and therefore more suitable for use in numerical methods. Expressions for stiffness and mass matrices are developed based on connection coefficients, which are inner products of basis functions and their derivatives. An example in 1-D was formulated using Central Difference and Newmark schemes for time differentiation. Encouraging results were obtained even for large time steps. Results obtained in 2-D are compared with the standard Finite Difference Method for validation. 展开更多
关键词 wavelets Interpolets Deslauriers-Dubuc Wavelet Finite Element Method Wave Propagation
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Nonstationary Wavelets Related to the Walsh Functions 被引量:1
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作者 Yuri A. Farkov Evgeny A. Rodionov 《American Journal of Computational Mathematics》 2012年第2期82-87,共6页
Using the Walsh-Fourier transform, we give a construction of compactly supported nonstationary dyadic wavelets on the positive half-line. The masks of these wavelets are the Walsh polynomials defined by finite sets of... Using the Walsh-Fourier transform, we give a construction of compactly supported nonstationary dyadic wavelets on the positive half-line. The masks of these wavelets are the Walsh polynomials defined by finite sets of parameters. Application to compression of fractal functions are also discussed. 展开更多
关键词 WALSH FUNCTIONS NONSTATIONARY DYADIC wavelets Fractal FUNCTIONS Adapted MULTIRESOLUTION Analysis
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Processing of 3D meshed surfaces using spherical wavelets 被引量:4
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作者 Hu Jianping Liu Xiuping +1 位作者 WangXiaochao and Xie Qi 《Computer Aided Drafting,Design and Manufacturing》 2012年第1期20-26,共7页
This paper presents an efficient technique for processing of 3D meshed surfaces via spherical wavelets. More specifically, an input 3D mesh is firstly transformed into a spherical vector signal by a fast low distortio... This paper presents an efficient technique for processing of 3D meshed surfaces via spherical wavelets. More specifically, an input 3D mesh is firstly transformed into a spherical vector signal by a fast low distortion spherical parameterization approach based on symmetry analysis of 3D meshes. This signal is then sampled on the sphere with the help of an adaptive sampling scheme. Finally, the sampled signal is transformed into the wavelet domain according to spherical wavelet transform where many 3D mesh processing operations can be implemented such as smoothing, enhancement, compression, and so on. Our main contribution lies in incorporating a fast low distortion spherical parameterization approach and an adaptive sampling scheme into the frame for pro- cessing 3D meshed surfaces by spherical wavelets, which can handle surfaces with complex shapes. A number of experimental ex- amples demonstrate that our algorithm is robust and efficient. 展开更多
关键词 mesh processing spherical parameterization adaptive sampling spherical wavelets
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NOVEL METHOD FOR TEXTURE DISCRIMINATION USING WAVELETS
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作者 刘建峰 戚飞虎 李春茂 《Journal of Shanghai Jiaotong university(Science)》 EI 1997年第1期50-54,共5页
NOVELMETHODFORTEXTUREDISCRIMINATIONUSINGWAVELETS*LiuJianfeng(刘建峰)QiFeihu(戚飞虎)(Dept.ofComputerScience,Shangha... NOVELMETHODFORTEXTUREDISCRIMINATIONUSINGWAVELETS*LiuJianfeng(刘建峰)QiFeihu(戚飞虎)(Dept.ofComputerScience,ShanghaiJiaotongUniv.)Jo... 展开更多
关键词 TEXTURE DISCRIMINATION wavelets WAVELET FRAME PACKETS
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Numerical scheme to solve a class of variable–order Hilfer–Prabhakar fractional differential equations with Jacobi wavelets polynomials
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作者 B.Bagherzadeh Tavasani A.H.Refahi Sheikhani H.Aminikhah 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第1期35-51,共17页
In this paper,we introduced a numerical approach for solving the fractional differential equations with a type of variable-order Hilfer-Prabhakar derivative of orderμ(t)andν(t).The proposed method is based on the Ja... In this paper,we introduced a numerical approach for solving the fractional differential equations with a type of variable-order Hilfer-Prabhakar derivative of orderμ(t)andν(t).The proposed method is based on the Jacobi wavelet collocation method.According to this method,an operational matrix is constructed.We use this operational matrix of the fractional derivative of variable-order to reduce the solution of the linear fractional equations to the system of algebraic equations.Theoretical considerations are discussed.Finally,some numerical examples are presented to demonstrate the accuracy of the proposed method. 展开更多
关键词 Hilfer-Prabhakar derivative Jacobi wavelets operational matrices variable order
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