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Chebyshev Pseudo-Spectral Method for Solving Fractional Advection-Dispersion Equation 被引量:2
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作者 N. H. Sweilam M. M. Khader M. Adel 《Applied Mathematics》 2014年第19期3240-3248,共9页
Fractional differential equations have recently been applied in various areas of engineering, science, finance, applied mathematics, bio-engineering and others. However, many researchers remain unaware of this field. ... Fractional differential equations have recently been applied in various areas of engineering, science, finance, applied mathematics, bio-engineering and others. However, many researchers remain unaware of this field. In this paper, an efficient numerical method for solving the fractional Advection-dispersion equation (ADE) is considered. The fractional derivative is described in the Caputo sense. The method is based on Chebyshev approximations. The properties of Chebyshev polynomials are used to reduce ADE to a system of ordinary differential equations, which are solved using the finite difference method (FDM). Moreover, the convergence analysis and an upper bound of the error for the derived formula are given. Numerical solutions of ADE are presented and the results are compared with the exact solution. 展开更多
关键词 FRACTIONAL ADVECTION-DISPERSION Equation Caputo FRACTIONAL DERIVATIVE Finite DIFFERENCE method chebyshev pseudo-spectral method Convergence Analysis
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比例时滞奇异微分方程的级数解与Chebyshev配置法
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作者 陈宏 王同科 《天津师范大学学报(自然科学版)》 北大核心 2025年第2期1-8,共8页
研究带有比例时滞的奇异微分方程的数值解.首先通过Picard迭代得到解在原点的级数展开式,然后据此设计一种准确的光滑变换,使得变换后方程的解充分光滑.对于变换后的方程设计微分和积分形式的Chebyshev-Gauss-Radau配置法,在有限区间上... 研究带有比例时滞的奇异微分方程的数值解.首先通过Picard迭代得到解在原点的级数展开式,然后据此设计一种准确的光滑变换,使得变换后方程的解充分光滑.对于变换后的方程设计微分和积分形式的Chebyshev-Gauss-Radau配置法,在有限区间上求得方程的数值解.针对积分形式的配置法证明其按最大范数具有最优阶收敛性.数值算例验证了所提方法在求解比例时滞微分方程时具有较高的精度. 展开更多
关键词 比例时滞奇异微分方程 分数阶级数解 光滑变换 chebyshev-Gauss-Radau配置法
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Flight strategy optimization for high-altitude long-endurance solar-powered aircraft based on Gauss pseudo-spectral method 被引量:23
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作者 Shaoqi WANG Dongli MA +2 位作者 Muqing YANG Liang ZHANG Guanxiong LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第10期2286-2298,共13页
Solar-powered aircraft have attracted great attention owing to their potential for longendurance flight and wide application prospects.Due to the particularity of energy system,flight strategy optimization is a signif... Solar-powered aircraft have attracted great attention owing to their potential for longendurance flight and wide application prospects.Due to the particularity of energy system,flight strategy optimization is a significant way to enhance the flight performance for solar-powered aircraft.In this study,a flight strategy optimization model for high-altitude long-endurance solar-powered aircraft was proposed.This model consists of three-dimensional kinematic model,aerodynamic model,energy collection model,energy store model and energy loss model.To solve the nonlinear optimal control problem with process constraints and terminal constraints,Gauss pseudo-spectral method was employed to discretize the state equations and constraint equations.Then a typical mission flying from given initial point to given final point within a time interval was considered.Results indicate that proper changes of the attitude angle contribute to increasing the energy gained by photovoltaic cells.Utilization of gravitational potential energy can partly take the role of battery pack.Integrating these two measures,the optimized flight strategy can improve the final state of charge compared with current constant-altitude constant-velocity strategy.The optimized strategy brings more profits on condition of lower sunlight intensity and shorter daytime. 展开更多
关键词 Battery PACK FLIGHT strategy optimization GAUSS pseudo-spectral method PHOTOVOLTAIC cell Solar-powered aircraft
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Chebyshev polynomial-based Ritz method for thermal buckling and free vibration behaviors of metal foam beams
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作者 N.D.NGUYEN T.N.NGUYEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期891-910,共20页
This study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam beams.The analyses include three models for porosity distribution and tw... This study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam beams.The analyses include three models for porosity distribution and two scenarios for thermal distribution.The material properties are assessed under two conditions,i.e.,temperature dependence and temperature independence.The theoretical framework for the beams is based on the higher-order shear deformation theory,which incorporates shear deformations with higher-order polynomials.The governing equations are established from the Lagrange equations,and the beam displacement fields are approximated by the Chebyshev polynomials.Numerical simulations are performed to evaluate the effects of thermal load,slenderness,boundary condition(BC),and porosity distribution on the buckling and vibration behaviors of metal foam beams.The findings highlight the significant influence of temperature-dependent(TD)material properties on metal foam beams'buckling and vibration responses. 展开更多
关键词 Ritz method chebyshev function BUCKLING VIBRATION metal foam beam higher-order beam theory(HOBT)
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Comparison of finite difference and pseudo-spectral methods in forward modelling based on metal ore model of random media 被引量:1
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作者 LIU Dongyu HAN Liguo +1 位作者 ZHANG Pan XU Dexin 《Global Geology》 2016年第2期102-108,共7页
With more applications of seismic exploration in metal ore exploration,forward modelling of seismic wave has become more important in metal ore. Finite difference method and pseudo-spectral method are two important me... With more applications of seismic exploration in metal ore exploration,forward modelling of seismic wave has become more important in metal ore. Finite difference method and pseudo-spectral method are two important methods of wave-field simulation. Results of previous studies show that both methods have distinct advantages and disadvantages: Finite difference method has high precision but its dispersion is serious; pseudospectral method considers both computational efficiency and precision but has less precision than finite-difference. The authors consider the complex structural characteristics of the metal ore,furthermore add random media in order to simulate the complex effects produced by metal ore for wave field. First,the study introduced the theories of random media and two forward modelling methods. Second,it compared the simulation results of two methods on fault model. Then the authors established a complex metal ore model,added random media and compared computational efficiency and precision. As a result,it is found that finite difference method is better than pseudo-spectral method in precision and boundary treatment,but the computational efficiency of pseudospectral method is slightly higher than the finite difference method. 展开更多
关键词 metal ORE RANDOM MEDIA FINITE DIFFERENCE method pseudo-spectral method
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An Accurate Numerical Solution for the Modified Equal Width Wave Equation Using the Fourier Pseudo-Spectral Method 被引量:1
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作者 Hany N. Hassan 《Journal of Applied Mathematics and Physics》 2016年第6期1054-1067,共14页
In this study, the numerical solution for the Modified Equal Width Wave (MEW) equation is presented using Fourier spectral method that use to discretize the space variable and Leap-frog method scheme for time dependen... In this study, the numerical solution for the Modified Equal Width Wave (MEW) equation is presented using Fourier spectral method that use to discretize the space variable and Leap-frog method scheme for time dependence. Test problems including the single soliton wave motion, interaction of two solitary waves and interaction of three solitary waves will use to validate the proposed method. The three invariants of the motion are evaluated to determine the conservation properties of the generated scheme. Finally, a Maxwellian initial condition pulse is then studied. The L<sub>2</sub> and L<sub>∞</sub> error norms are computed to study the accuracy and the simplicity of the presented method. 展开更多
关键词 The Modified Equal Width Wave Equation Fourier pseudo-spectral method Solitary Waves Fast Fourier Transform
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基于Chebyshev谱法求解具有时变系数的广义Fitzhugh-Nagumo方程
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作者 罗妍 宋灵宇 《佳木斯大学学报(自然科学版)》 2025年第3期166-170,共5页
基于对称时空切比雪夫谱法,研究不同类型的具有Dirichlet边界条件的Fitzhugh-Nagumo方程的数值方法。用Chebyshev-Gauss-Lobatto点将计算区间离散化,得到切比雪夫点处的导数并将其写成矩阵形式得到切比雪夫导数矩阵,由此将Fitzhugh-Nag... 基于对称时空切比雪夫谱法,研究不同类型的具有Dirichlet边界条件的Fitzhugh-Nagumo方程的数值方法。用Chebyshev-Gauss-Lobatto点将计算区间离散化,得到切比雪夫点处的导数并将其写成矩阵形式得到切比雪夫导数矩阵,由此将Fitzhugh-Nagumo方程近似为常微分方程,并且证明了该方法的稳定性和收敛性。通过数值实验将所提出的方法与其他方法进行比较,得到Fitzhugh-Nagumo方程更精确的解。 展开更多
关键词 FITZHUGH-NAGUMO方程 chebyshev谱法 chebyshev-Gauss-Lobatto点
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Pseudo-Spectral Method for Space Fractional Diffusion Equation
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作者 Yiting Huang Minling Zheng 《Applied Mathematics》 2013年第11期1495-1502,共8页
This paper presents a numerical scheme for space fractional diffusion equations (SFDEs) based on pseudo-spectral method. In this approach, using the Guass-Lobatto nodes, the unknown function is approximated by orthogo... This paper presents a numerical scheme for space fractional diffusion equations (SFDEs) based on pseudo-spectral method. In this approach, using the Guass-Lobatto nodes, the unknown function is approximated by orthogonal polynomials or interpolation polynomials. Then, by using pseudo-spectral method, the SFDE is reduced to a system of ordinary differential equations for time variable t. The high order Runge-Kutta scheme can be used to solve the system. So, a high order numerical scheme is derived. Numerical examples illustrate that the results obtained by this method agree well with the analytical solutions. 展开更多
关键词 Riemann-Liouville DERIVATIVE pseudo-spectral method COLLOCATION method FRACTIONAL DIFFUSION EQUATION
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Calculation of Turbulent Flow with Pseudo-spectral Method
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作者 梁志勇 谢峰 张根宝 《Journal of Donghua University(English Edition)》 EI CAS 2009年第3期329-332,共4页
This paper deals with the numerical simulation of incompressible turbulent boundary flow of a flat plate with the pseudo-spectral matrix method. In order to appear more than 10 nodes in the turbulent base-stratum and ... This paper deals with the numerical simulation of incompressible turbulent boundary flow of a flat plate with the pseudo-spectral matrix method. In order to appear more than 10 nodes in the turbulent base-stratum and transition of 43×43 computational grids,a coordinate transformation is put up from physical panel to computational panel. Several zero turbulent models are computed comparatively. The results are credible when comparing with the previous methods. 展开更多
关键词 pseudo-spectral method flat plate turbulent flow CALCULATION
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Solving a Nonlinear Multi-Order Fractional Differential Equation Using Legendre Pseudo-Spectral Method
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作者 Yin Yang 《Applied Mathematics》 2013年第1期113-118,共6页
In this paper, we apply the Legendre spectral-collocation method to obtain approximate solutions of nonlinear multi-order fractional differential equations (M-FDEs). The fractional derivative is described in the Caput... In this paper, we apply the Legendre spectral-collocation method to obtain approximate solutions of nonlinear multi-order fractional differential equations (M-FDEs). The fractional derivative is described in the Caputo sense. The study is conducted through illustrative example to demonstrate the validity and applicability of the presented method. The results reveal that the proposed method is very effective and simple. Moreover, only a small number of shifted Legendre polynomials are needed to obtain a satisfactory result. 展开更多
关键词 LEGENDRE pseudo-spectral method Multi-Order FRACTIONAL DIFFERENTIAL EQUATIONS Caputo DERIVATIVE
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基于广义KdV-Burgers方程的全对角化Chebyshev Dual-Petrov-Galerkin谱方法
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作者 安筱 李珊 《计算机与数字工程》 2025年第3期628-631,共4页
针对有限区域上广义KdV-Burgers方程,提出了全对角化的Chebyshev dual-Petrov-Galerkin谱方法。该方法在数值模拟KdV-Burgers方程的扭结波解时是准确有效的,数值结果表明了该方法的精确性和高效性,且与以往算法相比,新算法优化了计算过... 针对有限区域上广义KdV-Burgers方程,提出了全对角化的Chebyshev dual-Petrov-Galerkin谱方法。该方法在数值模拟KdV-Burgers方程的扭结波解时是准确有效的,数值结果表明了该方法的精确性和高效性,且与以往算法相比,新算法优化了计算过程,减少了计算量,并且简单易行。 展开更多
关键词 chebyshev dual-Petrov-Galerkin谱方法 全对角化 KdV-Burgers方程 数值结果
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Collision-inducing method for UAV evasive maneuvers based on receding horizon optimization
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作者 Haonan Tang Zhigong Tang +1 位作者 Gong Chen Jifeng Guo 《Defence Technology(防务技术)》 2025年第8期141-154,共14页
Aiming at the missile avoidance problem of the unmanned aerial vehicle(UAV)in complex obstacle environments,this work proposes a collision-avoidance method based on receding horizon optimization.The proposed method ge... Aiming at the missile avoidance problem of the unmanned aerial vehicle(UAV)in complex obstacle environments,this work proposes a collision-avoidance method based on receding horizon optimization.The proposed method generated a specific trajectory for the UAV to effectively induce the proportional navigation missile to successfully intercept the obstacle,thereby accomplishing the evasive maneuver.The evasive maneuver was divided into two distinct stages,namely the collision-inducing phase and the fast departure phase.The obstacle potential field-based target selection algorithm was employed to identify the most appropriate target obstacle,while the induced trajectory was determined through a combination of receding horizon optimization and the hp-adaptive pseudo-spectral method.Simulation experiments were carried out under three different types of obstacle environments and one multiobstacle environment,and the simulation results show that the method proposed in this paper greatly improves the success rate of UAV evasive maneuvers,proving the effectiveness of this method. 展开更多
关键词 UAV MISSILE Proportional navigation Evasive maneuver Receding horizon optimization Hp-adaptive pseudo-spectral method
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An Efficient Synthesizing Method for Super-Massive Sparse Phased Array in Non-Terrestrial Network Applications
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作者 Yin Haoyu Zhao Haiyan +2 位作者 Li Weidong Hao Zhangcheng Hong Wei 《China Communications》 2025年第10期1-11,共11页
In this paper,a method for designing supermassive sparse phased arrays(SMSPAs)known as the unitary modified matrix enhancement and matrix pencil(UMMEMP)method is proposed.In this method,an eigenvalue pairing method,wh... In this paper,a method for designing supermassive sparse phased arrays(SMSPAs)known as the unitary modified matrix enhancement and matrix pencil(UMMEMP)method is proposed.In this method,an eigenvalue pairing method,which is inspired by the modified MEMP,effectively pairs the repeated eigenvalues intractable in the unitary matrix pencil method,and it is more effective in determining the locations of elements in the sparse array.Three numerical examples and a full-wave validation are presented to demonstrate the effectiveness of the method,implemented via SMSPA,in achieving low sidelobe level wide-angle scanning radiation patterns,circular flattop radiation patterns,and ultra wide-angle scanning radiation patterns. 展开更多
关键词 chebyshev array circular flat-top pattern pairing method super-massive sparse phased array ultra wide-angle scanning unitary modified matrix enhancement and matrix pencil
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THE ACCURACY COMPARISON BETWEEN CHEBYSHEV-τ METHOD AND CHEBYSHEV COLLOCATION METHOD
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作者 方一红 罗纪生 《Transactions of Tianjin University》 EI CAS 1997年第2期67-71,共5页
This paper is devoted to investigate the accuracy of the Pseudo spectral scheme with the Chebyshev tau method and Chebyshev collocation method. The computational results of the nonlinear disturbance development in p... This paper is devoted to investigate the accuracy of the Pseudo spectral scheme with the Chebyshev tau method and Chebyshev collocation method. The computational results of the nonlinear disturbance development in plane Poiseuille flow for both methods are presented and compared in detail. It is acknowledged that the Chebyshev collocation method has higher precision than the other one, especially for near netural situation. 展开更多
关键词 chebyshev tau method chebyshev collocation method Pseudo spectral scheme DISTURBANCE
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Direct trajectory optimization based on a mapped Chebyshev pseudospectral method 被引量:19
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作者 Guo Xiao Zhu Ming 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第2期401-412,共12页
In view of generating optimal trajectories of Bolza problems, standard Chebyshev pseudospectral (PS) method makes the points' accumulation near the extremities and rarefaction of nodes close to the center of interv... In view of generating optimal trajectories of Bolza problems, standard Chebyshev pseudospectral (PS) method makes the points' accumulation near the extremities and rarefaction of nodes close to the center of interval, which causes an ill-condition of differentiation matrix and an oscillation of the optimal solution. For improvement upon the difficulties, a mapped Chebyshev pseudospectral method is proposed. A conformal map is applied to Chebyshev points to move the points closer to equidistant nodes. Condition number and spectral radius of differentiation matrices from both methods are presented to show the improvement. Furthermore, the modification keeps the Chebyshev pseudospectral method's advantage, the spectral convergence rate. Based on three numerical examples, a comparison of the execution time, convergence and accuracy is presented among the standard Chebyshev pseudospectral method, other collocation methods and the proposed one. In one example, the error of results from mapped Chebyshev pseudospectral method is reduced to 5% of that from standard Chebyshev pseudospectral method. 展开更多
关键词 chebyshev approximation Conformal shift INTERPOLATION Optimization Pseudospectral method TRAJECTORY
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ON A FAMILY OF CHEBYSHEV-HALLEY TYPE METHODS IN BANACH SPACE UNDER WEAKER SMALE CONDITION 被引量:3
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作者 黄正达 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第1期37-44,共8页
In this paper, we discuss local convergence of a family of Chebychev Halley type methods with a parameter θ∈[0,1] in Banach space using Smale type δ criterion under 2 th γ condition. We will see that the propertie... In this paper, we discuss local convergence of a family of Chebychev Halley type methods with a parameter θ∈[0,1] in Banach space using Smale type δ criterion under 2 th γ condition. We will see that the properties of the condition used for local convergence is much more different from that used in [6][15] for the semi-local convergence. 展开更多
关键词 chebyshev HALLEY type methods 2 th γ CONDITION δ criterion.
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Precise integration methods based on the Chebyshev polynomial of the first kind 被引量:2
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作者 Wang Mengfu F. T. K. Au 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第2期207-216,共10页
This paper introduces two new types of precise integration methods based on Chebyshev polynomial of the first kind for dynamic response analysis of structures, namely the integral formula method (IFM) and the homoge... This paper introduces two new types of precise integration methods based on Chebyshev polynomial of the first kind for dynamic response analysis of structures, namely the integral formula method (IFM) and the homogenized initial system method (HISM). In both methods, nonlinear variable loadings within time intervals are simulated using Chebyshev polynomials of the first kind before a direct integration is performed. Developed on the basis of the integral formula, the recurrence relationship of the integral computation suggested in this paper is combined with the Crout decomposed method to solve linear algebraic equations. In this way, the IFM based on Chebyshev polynomial of the first kind is constructed. Transforming the non-homogenous initial system to the homogeneous dynamic system, and developing a special scheme without dimensional expansion, the HISM based on Chebyshev polynomial of the first kind is able to avoid the matrix inversion operation. The accuracy of the time integration schemes is examined and compared with other commonly used schemes, and it is shown that a greater accuracy as well as less time consuming can be achieved. Two numerical examples are presented to demonstrate the applicability of these new methods. 展开更多
关键词 structural dynamics chebyshev polynomial of the first kind the Crout decomposed method integral formula method homogenized initial system method
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Dynamic analysis of beam-cable coupled systems using Chebyshev spectral element method 被引量:2
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作者 Yi-Xin Huang Hao Tian Yang Zhao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第5期954-962,共9页
The dynamic characteristics of a beam-cable coupled system are investigated using an improved Chebyshev spectral element method in order to observe the effects of adding cables on the beam. The system is modeled as a ... The dynamic characteristics of a beam-cable coupled system are investigated using an improved Chebyshev spectral element method in order to observe the effects of adding cables on the beam. The system is modeled as a double Timoshenko beam system interconnected by discrete springs. Utilizing Chebyshev series expansion and meshing the system according to the locations of its connections, numerical results of the natural frequencies and mode shapes are obtained using only a few elements, and the results are validated by comparing them with the results of a finite-element method. Then the effects of the cable parameters and layout of connections on the natural frequencies and mode shapes of a fixed-pinned beam are studied. The results show that the modes of a beam-cable coupled system can be classified into two types, beam mode and cable mode, according to the dominant deformation. To avoid undesirable vibrations of the cable, its parameters should be controlled in a reasonable range, or the layout of the connections should be optimized. 展开更多
关键词 Beam-cable coupled system Double-beam system chebyshev spectral element method Natural frequency Mode shape
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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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A lumped mass Chebyshev spectral element method and its application to structural dynamic problems 被引量:4
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作者 Wang Jingxiong Li Hongjing Xing Haojie 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第3期843-859,共17页
A diagonal or lumped mass matrix is of great value for time-domain analysis of structural dynamic and wave propagation problems,as the computational efforts can be greatly reduced in the process of mass matrix inversi... A diagonal or lumped mass matrix is of great value for time-domain analysis of structural dynamic and wave propagation problems,as the computational efforts can be greatly reduced in the process of mass matrix inversion.In this study,the nodal quadrature method is employed to construct a lumped mass matrix for the Chebyshev spectral element method(CSEM).A Gauss-Lobatto type quadrature,based on Gauss-Lobatto-Chebyshev points with a weighting function of unity,is thus derived.With the aid of this quadrature,the CSEM can take advantage of explicit time-marching schemes and provide an efficient new tool for solving structural dynamic problems.Several types of lumped mass Chebyshev spectral elements are designed,including rod,beam and plate elements.The performance of the developed method is examined via some numerical examples of natural vibration and elastic wave propagation,accompanied by their comparison to that of traditional consistent-mass CSEM or the classical finite element method(FEM).Numerical results indicate that the proposed method displays comparable accuracy as its consistent-mass counterpart,and is more accurate than classical FEM.For the simulation of elastic wave propagation in structures induced by high-frequency loading,this method achieves satisfactory performance in accuracy and efficiency. 展开更多
关键词 mass lumping chebyshev spectral element method Gauss-Lobatto-chebyshev points Gauss-Lobatto type quadrature structural dynamic analysis elastic wave propagation
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