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关于矩阵方程X+A~*X^(-1)A=P的解及其扰动分析 被引量:19
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作者 陈小山 黎稳 《计算数学》 CSCD 北大核心 2005年第3期303-310,共8页
考虑非线性矩阵方程X+A~*X^(-1)A=P,其中A是n阶非奇异复矩阵,P是n阶Hermite正定矩阵.本文给出了Hermite正定解和最大解的存在性以及获得最大解的一阶扰动界,改进了文[5,6]中的部分结论.
关键词 最大解 谱范数 酉不变范数 非线性矩阵方程 扰动分析 hermite 解的存在性 正定矩阵 复矩阵 非奇异
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Deriving new operator identities by alternately using normally,antinormally,and Weyl ordered integration technique 被引量:14
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作者 FAN HongYi1,YUAN HongChun1 & JIANG NianQuan2 1Department of Physics,Shanghai Jiao Tong University,Shanghai 200030,China 2College of Physics and Electric Information,Wenzhou University,Wenzhou 325035,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第9期1626-1630,共5页
Dirac's ket-bra formalism is the language of quantum mechanics.We have reviewed how to apply Newton-Leibniz integration rules to Dirac's ket-bra projectors in previous work.In this work,by alternately using th... Dirac's ket-bra formalism is the language of quantum mechanics.We have reviewed how to apply Newton-Leibniz integration rules to Dirac's ket-bra projectors in previous work.In this work,by alternately using the technique of integration within normal,antinormal,and Weyl ordering of operators we not only derive some new operator ordering identities,but also deduce some new integration formulas regarding Laguerre and Hermite polynomials.This may open a new route of directly deriving some complicated mathematical integration formulas by virtue of the quantum mechanical operator ordering technique,without really performing the integrations in the ordinary way. 展开更多
关键词 OPERATOR ordering IDENTITIES LAGUERRE and hermite polynomials the IWOP technique
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The Simultaneous Approximation Order by Hermite Interpolation in a Smooth Domain 被引量:12
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作者 Tian Liang TU Department of Information Engineering, North China Institute of Hydroelectricity, Zhengzhou 450045, P. R. China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2002年第4期631-646,共16页
Let D be a smooth domain in the complex plane. In D consider the simultaneous ap- proximation to a function and its ith (0≤i≤q) derivatives by Hermite interpolation. The orders of uniform approximation and approxima... Let D be a smooth domain in the complex plane. In D consider the simultaneous ap- proximation to a function and its ith (0≤i≤q) derivatives by Hermite interpolation. The orders of uniform approximation and approximation in the mean, are obtained under some domain boundary conditions. Some known results are included as particular cases of the theorems of this paper. 展开更多
关键词 Simultaneous appoximation hermite interpolation Approximation order Smooth domian
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光束分数傅里叶变换的Wigner分布函数分析方法 被引量:9
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作者 吴平 吕百达 陈天禄 《物理学报》 SCIE EI CAS CSCD 北大核心 2005年第2期658-664,共7页
利用Wigner分布函数 (WDF)方法 ,对光束的分数傅里叶变换特性进行了研究 .以厄米 高斯 (H G)光束为例 ,导出了H G光束在分数傅里叶变换面上光强分布的解析公式和H G光束在分数傅里叶变换面上束宽的解析计算公式 .通过数值计算研究了H G... 利用Wigner分布函数 (WDF)方法 ,对光束的分数傅里叶变换特性进行了研究 .以厄米 高斯 (H G)光束为例 ,导出了H G光束在分数傅里叶变换面上光强分布的解析公式和H G光束在分数傅里叶变换面上束宽的解析计算公式 .通过数值计算研究了H G光束光强随分数傅里叶变换阶数变化的规律 .研究表明 :选取适当的分数傅里叶变换阶数p ,在x ,y方向可以得到相等束宽的对称光强分布 . 展开更多
关键词 分数傅里叶变换 WIGNER分布函数 光束 光强分布 阶数 解析计算公式 相等 束宽 高斯 对称
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A Note on Hermite and Subelliptic Operators 被引量:7
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作者 Der Chen CHANG Jing Zhi TIE 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第4期803-818,共16页
In this note, we compute the fundamental solution for the Hermite operator with singularity at an arbitrary point y∈R^n. We also apply this result to obtain the fundamental solutions for the Grushin operator in R^2 a... In this note, we compute the fundamental solution for the Hermite operator with singularity at an arbitrary point y∈R^n. We also apply this result to obtain the fundamental solutions for the Grushin operator in R^2 and the sub-Laplacian in the Heisenberg group Hn. 展开更多
关键词 hermite operator Heisenberg group SUB-LAPLACIAN Gruhsin operator Heat kernel Laguerre function
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A class of the fourth order finite volume Hermite weighted essentially non-oscillatory schemes 被引量:7
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作者 ZHU Jun QIU JianXian 《Science China Mathematics》 SCIE 2008年第8期1549-1560,共12页
In this paper,we developed a class of the fourth order accurate finite volume Hermite weighted essentially non-oscillatory(HWENO)schemes based on the work(Computers&Fluids,34:642-663(2005))by Qiu and Shu,with Tota... In this paper,we developed a class of the fourth order accurate finite volume Hermite weighted essentially non-oscillatory(HWENO)schemes based on the work(Computers&Fluids,34:642-663(2005))by Qiu and Shu,with Total Variation Diminishing Runge-Kutta time discretization method for the two-dimensional hyperbolic conservation laws.The key idea of HWENO is to evolve both with the solution and its derivative,which allows for using Hermite interpolation in the reconstruction phase,resulting in a more compact stencil at the expense of the additional work.The main difference between this work and the formal one is the procedure to reconstruct the derivative terms.Comparing with the original HWENO schemes of Qiu and Shu,one major advantage of new HWENOschemes is its robust in computation of problem with strong shocks.Extensive numerical experiments are performed to illustrate the capability of the method. 展开更多
关键词 finite volume HWENO scheme conservation laws hermite polynomial TVD Runge-Kutta time discretization method 65M06 65M99 35L65
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有理等距曲线的C^2Hermite插值 被引量:3
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作者 陈国栋 王国瑾 《工程图学学报》 CSCD 2000年第3期64-69,共6页
研究了有理等距参数曲线的Hermite插值问题,用显式给出了相应的Bézier曲线表示及其控制顶点的计算公式,所得插值曲线中通常有4条曲线具有很好的形状特征,且至少有一条曲线与通常的五次Hermite插值曲线具有极为相似的形状特征。... 研究了有理等距参数曲线的Hermite插值问题,用显式给出了相应的Bézier曲线表示及其控制顶点的计算公式,所得插值曲线中通常有4条曲线具有很好的形状特征,且至少有一条曲线与通常的五次Hermite插值曲线具有极为相似的形状特征。结合绝对旋转数概念和曲线能量最小化,给出了最佳Hermite插值曲线的选择方法。 展开更多
关键词 有理等距参数曲线 hermite 旋转数 能量
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奇异积分的广义Hermite插值样条逼近 被引量:8
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作者 黄小玲 《计算数学》 CSCD 北大核心 1992年第2期147-151,共5页
§1.引言 本文利用广义Hermite插值样条讨论如下形式的奇异积分:的逼近,其中w(t)为权函数,积分理解为Cauchy主值积分. 以带权正交多项式作为逼近工具的奇异积分逼近方法,在实际应用中常会遇到许多困难,如确定权函数相应的正交多项... §1.引言 本文利用广义Hermite插值样条讨论如下形式的奇异积分:的逼近,其中w(t)为权函数,积分理解为Cauchy主值积分. 以带权正交多项式作为逼近工具的奇异积分逼近方法,在实际应用中常会遇到许多困难,如确定权函数相应的正交多项式及其零点、计算过程的不稳定性等. 展开更多
关键词 奇异积分 逼近 插值样条 hermite
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具有最小曲率变化率的几何Hermite曲线 被引量:3
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作者 迟静 张彩明 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2008年第7期882-887,共6页
通过在Hermite插值过程中最优化端点切矢的模长,使最优几何Hermite曲线的曲率变化率最小;得到并证明了使最优几何Hermite曲线达到几何光顺的切矢角约束条件.针对切矢角不满足该约束条件的情况,提出了构造2-分段和3-分段组合最优几何Herm... 通过在Hermite插值过程中最优化端点切矢的模长,使最优几何Hermite曲线的曲率变化率最小;得到并证明了使最优几何Hermite曲线达到几何光顺的切矢角约束条件.针对切矢角不满足该约束条件的情况,提出了构造2-分段和3-分段组合最优几何Hermite曲线的方法.最后通过实例及比较表明,该方法与基于应变能最小的方法可相互补充,在整个切矢角区域上达到满意的效果. 展开更多
关键词 曲率变化率 应变能 几何光顺 hermite
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Hermite样条在建立塔台模拟机飞机运动路径中的应用 被引量:5
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作者 宋先锋 何贤江 王丹霞 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第3期624-627,共4页
Authors introduced an algorithmmodeusingHermitesplinetofitplanemovementroute,particular lydiscussedthekeyproblem———howtomakethevalueofextremepoint’stangentvectormode,andpro posedanewmethodof“SearchingModewithTria... Authors introduced an algorithmmodeusingHermitesplinetofitplanemovementroute,particular lydiscussedthekeyproblem———howtomakethevalueofextremepoint’stangentvectormode,andpro posedanewmethodof“SearchingModewithTriangle”tofindthetangentvectormode.Experimentalresult showsthattheperformanceandtheeffectaresuperiortotraditionalmethods. 展开更多
关键词 塔台模拟机 hermite 运动路径 应用 飞机 在建 样条 虚拟现实系统 控制命令 运动目标 工作环境 核心模块 计算模块 状态信息 实时计算 仪表
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A Novel Pulse Design Based on Hermite Functions for UWB Communications 被引量:4
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作者 JIANG Guang-xing ZHU Hong-bo CAO Wei 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2006年第1期49-52,共4页
This paper presents the design of a class of pulses that are based on Hermite functions for ultra-wideband communication systems. The presented class of pulses can not only meet the power spectral emission constraints... This paper presents the design of a class of pulses that are based on Hermite functions for ultra-wideband communication systems. The presented class of pulses can not only meet the power spectral emission constraints of federal communications commission, but also have a short duration for multiple accesses. This paper gives closed form expressions of auto-and cross-correlation functions of the proposed pulses, which can be used to evaluate the performance of the correlator receiver. Furthermore, the paper investigates, under various channel conditions, the spectrum characteristic and the bit error rate of the pulses' wave forms. The investigation conditions include additive white Gaussian noise channels, multipleaccess interference channels, and fading multipath channels. Our results indicate that our systematic algorithm is flexible for designing ultra-wideband pulses that conform to spectral emission constraints and offer good bit error rate performance. 展开更多
关键词 pulse design UWB hermite functions multiple access MULTIPATH
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The s-ordered expansions of the operator function about the combined quadrature μX + νP 被引量:4
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作者 HongChun Yuan XueXiang Xu HongYi Fan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第10期1793-1798,共6页
A general framework applicable to deriving the s-ordered operator expansions is presented in this paper.We firstly deduce the s-ordered operator expansion formula of density operator ρ a?,a and introduce the techniqu... A general framework applicable to deriving the s-ordered operator expansions is presented in this paper.We firstly deduce the s-ordered operator expansion formula of density operator ρ a?,a and introduce the technique of integration within the sordered product of operators (IWSOP).Based on the deduction and the technique,we derive the s-ordered expansions of operators (μX + νP)n and Hn (μX + νP) (linear combinations of the coordinate operator X and the momentum operator P,Hn (x) is Hermite polynomial),respectively,and discuss some special cases of s=1,0,-1.Some new useful operator identities are obtained as well. 展开更多
关键词 s-ordered OPERATOR expansion formula COMBINED QUADRATURE μX + νP hermite polynomial IWSOP technique
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Duality between Bessel Functions and Chebyshev Polynomials in Expansions of Functions
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2023年第8期504-536,共16页
In expansions of arbitrary functions in Bessel functions or Spherical Bessel functions, a dual partner set of polynomials play a role. For the Bessel functions, these are the Chebyshev polynomials of first kind and fo... In expansions of arbitrary functions in Bessel functions or Spherical Bessel functions, a dual partner set of polynomials play a role. For the Bessel functions, these are the Chebyshev polynomials of first kind and for the Spherical Bessel functions the Legendre polynomials. These two sets of functions appear in many formulas of the expansion and in the completeness and (bi)-orthogonality relations. The analogy to expansions of functions in Taylor series and in moment series and to expansions in Hermite functions is elaborated. Besides other special expansion, we find the expansion of Bessel functions in Spherical Bessel functions and their inversion and of Chebyshev polynomials of first kind in Legendre polynomials and their inversion. For the operators which generate the Spherical Bessel functions from a basic Spherical Bessel function, the normally ordered (or disentangled) form is found. 展开更多
关键词 Spherical Bessel Functions Chebyshev Polynomials Legendre Polynomials hermite Polynomials Derivatives of Delta Functions Normally and Anti-Normally Ordered Operators
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Hermite Positive Definite Solution of the Quaternion Matrix Equation Xm + B*XB = C
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作者 Yiwen Yao Guangmei Liu +1 位作者 Yanting Zhang Jingpin Huang 《Journal of Applied Mathematics and Physics》 2023年第11期3760-3772,共13页
This paper discusses the necessary and sufficient conditions for the existence of Hermite positive definite solutions of the quaternion matrix equation X<sup>m</sup>+ B*XB = C (m > 0) and its iterative ... This paper discusses the necessary and sufficient conditions for the existence of Hermite positive definite solutions of the quaternion matrix equation X<sup>m</sup>+ B*XB = C (m > 0) and its iterative solution method. According to the characteristics of the coefficient matrix, a corresponding algebraic equation system is ingeniously constructed, and by discussing the equation system’s solvability, the matrix equation’s existence interval is obtained. Based on the characteristics of the coefficient matrix, some necessary and sufficient conditions for the existence of Hermitian positive definite solutions of the matrix equation are derived. Then, the upper and lower bounds of the positive actual solutions are estimated by using matrix inequalities. Four iteration formats are constructed according to the given conditions and existence intervals, and their convergence is proven. The selection method for the initial matrix is also provided. Finally, using the complexification operator of quaternion matrices, an equivalent iteration on the complex field is established to solve the equation in the Matlab environment. Two numerical examples are used to test the effectiveness and feasibility of the given method. . 展开更多
关键词 QUATERNION Matrix Equation hermite Positive Definite Solution Matrix Inequality ITERATIVE CONVERGENCE
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The best quadrature formula based on Hermite information for the class KW^(2)[a,b] 被引量:4
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作者 WANG Xinghua MI Xiangjiang 《Science China Mathematics》 SCIE 2005年第1期79-87,共9页
The best quadrature formula has been found in the following sense: for a function whose norm of the second derivative is bounded by a given constant and the best quadrature formula for the approximate evaluation of in... The best quadrature formula has been found in the following sense: for a function whose norm of the second derivative is bounded by a given constant and the best quadrature formula for the approximate evaluation of integration of that function can minimize the worst possible error if the values of the function and its derivative at certain nodes are known.The best interpolation formula used to get the quadrature formula above is also found.Moreover,we compare the best quadrature formula with the open compound corrected trapezoidal formula by theoretical analysis and stochastic experiments. 展开更多
关键词 CLASS of second DIFFERENTIABLE functions hermite information best quadrature formula best interpolation method stochastic experiment open compound corrected trapezoidal formula Iyengar-type inequalities.
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HERMITE MATRIX POLYNOMIALS AND SECOND ORDER MATRIX DIFFERENTIAL EQUATIONS 被引量:6
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作者 L.Jódar R.Company 《Analysis in Theory and Applications》 1996年第2期20-30,共11页
In this paper we introduce the class of Hermite's matrix polynomials which appear as finite series solutions of second order matrix differential equations Y'-xAY'+BY=0.An explicit expression for the Hermit... In this paper we introduce the class of Hermite's matrix polynomials which appear as finite series solutions of second order matrix differential equations Y'-xAY'+BY=0.An explicit expression for the Hermite matrix polynomials,the orthogonality property and a Rodrigues' formula are given. 展开更多
关键词 exp hermite MATRIX POLYNOMIALS AND SECOND ORDER MATRIX DIFFERENTIAL EQUATIONS
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HERMITE—BIRKHOFF INTERPOLATION OF SCATTERED DATA BY RADIAL BASIS FUNCTIONS 被引量:5
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作者 吴宗敏 《Analysis in Theory and Applications》 1992年第2期1-10,共10页
For Hermite-Birkhoff interpolation of scattered multidumensional data by radial basis function (?),existence and characterization theorems and a variational principle are proved. Examples include (?)(r)=r^b,Duchon'... For Hermite-Birkhoff interpolation of scattered multidumensional data by radial basis function (?),existence and characterization theorems and a variational principle are proved. Examples include (?)(r)=r^b,Duchon's thin-plate splines,Hardy's multiquadrics,and inverse multiquadrics. 展开更多
关键词 hermite BIRKHOFF INTERPOLATION OF SCATTERED DATA BY RADIAL BASIS FUNCTIONS
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An oscillation-free Hermite WENO scheme for hyperbolic conservation laws
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作者 Zhuang Zhao Jianxian Qiu 《Science China Mathematics》 SCIE CSCD 2024年第2期431-454,共24页
In this paper, the sixth-order oscillation-free Hermite weighted essentially non-oscillatory (OFHWENO) scheme is proposed for hyperbolic conservation laws on structured meshes, where the zeroth- andfirst-order moments... In this paper, the sixth-order oscillation-free Hermite weighted essentially non-oscillatory (OFHWENO) scheme is proposed for hyperbolic conservation laws on structured meshes, where the zeroth- andfirst-order moments are the variables for the governing equations. The main difference from other HWENOschemes existing in the literature is that we add high-order numerical damping terms in the first-order momentequations to control spurious oscillations for the OF-HWENO scheme. The OF-HWENO scheme not only canachieve the designed optimal numerical order, but also can be easily implemented as we use only one set ofstencils in the reconstruction procedure and the same reconstructed polynomials are applied for the zeroth- andfirst-order moment equations. In order to obtain the adaptive order resolution when facing discontinuities, atransition polynomial is added in the reconstruction, where the associated linear weights can also be any positivenumbers as long as their summation equals one. In addition, the OF-HWENO scheme still keeps compactnessas only immediate neighbor values are needed in the space discretization. Some benchmark numerical tests areperformed to illustrate the high-order accuracy, high resolution and robustness of the proposed scheme. 展开更多
关键词 hermite WENO scheme hyperbolic conservation laws oscillation-free adaptive order discontinuous Galerkin method
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Quantum entangled fractional Fourier transform based on the IWOP technique 被引量:2
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作者 张科 李兰兰 +3 位作者 余盼盼 周莹 郭大伟 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期165-170,共6页
In our previous papers,the classical fractional Fourier transform theory was incorporated into the quantum theoretical system using the theoretical method of quantum optics,and the calculation produced quantum mechani... In our previous papers,the classical fractional Fourier transform theory was incorporated into the quantum theoretical system using the theoretical method of quantum optics,and the calculation produced quantum mechanical operators corresponding to the generation of fractional Fourier transform.The core function of the coordinate-momentum exchange operators in the addition law of fractional Fourier transform was analyzed too.In this paper,the bivariate operator Hermite polynomial theory and the technique of integration within an ordered product of operators(IWOP)are used to establish the entanglement fractional Fourier transform theory to the extent of quantum.A new function generating formula and an operator for generating quantum entangled fractional Fourier transform are obtained using the fractional Fourier transform relationship in a pair of conjugated entangled state representations. 展开更多
关键词 fractional Fourier transform coordinate-momentum exchange operators bivariate operator hermite polynomial theory the technique of integration within an ordered product of operators quantum entangled fractional Fourier transform
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A Class Hermite Pseudospectral Approximate with ω(x) ≡ 1 and Application to Reaction-diffusion Equation 被引量:2
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作者 Xin-min Xiang 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第3期405-414,共10页
In this paper, we continue the discussion of [12] to establish the Hermite pseudospectral method with weight ω(x) = 1. As an application, we consider the pseudospectral approximation of the reaction-diffusion equat... In this paper, we continue the discussion of [12] to establish the Hermite pseudospectral method with weight ω(x) = 1. As an application, we consider the pseudospectral approximation of the reaction-diffusion equation on the whole line, we prove the existence of the approximate attractor and give the error estimate for the approximate solution. 展开更多
关键词 hermite pseudospectral method hermite function system which the weight is 1 Reaction-diffusionequation Global attractor Error estimate
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