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Evolutionary Safe Padé Approximation Scheme for Dynamical Study of Nonlinear Cervical Human Papilloma Virus Infection Model
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作者 Javaid Ali Armando Ciancio +4 位作者 Kashif Ali Khan Nauman Raza Haci Mehmet Baskonus Muhammad Luqman Zafar-Ullah Khan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2275-2296,共22页
This study proposes a structure-preserving evolutionary framework to find a semi-analytical approximate solution for a nonlinear cervical cancer epidemic(CCE)model.The underlying CCE model lacks a closed-form exact so... This study proposes a structure-preserving evolutionary framework to find a semi-analytical approximate solution for a nonlinear cervical cancer epidemic(CCE)model.The underlying CCE model lacks a closed-form exact solution.Numerical solutions obtained through traditional finite difference schemes do not ensure the preservation of the model’s necessary properties,such as positivity,boundedness,and feasibility.Therefore,the development of structure-preserving semi-analytical approaches is always necessary.This research introduces an intelligently supervised computational paradigm to solve the underlying CCE model’s physical properties by formulating an equivalent unconstrained optimization problem.Singularity-free safe Padérational functions approximate the mathematical shape of state variables,while the model’s physical requirements are treated as problem constraints.The primary model of the governing differential equations is imposed to minimize the error between approximate solutions.An evolutionary algorithm,the Genetic Algorithm with Multi-Parent Crossover(GA-MPC),executes the optimization task.The resulting method is the Evolutionary Safe PadéApproximation(ESPA)scheme.The proof of unconditional convergence of the ESPA scheme on the CCE model is supported by numerical simulations.The performance of the ESPA scheme on the CCE model is thoroughly investigated by considering various orders of non-singular Padéapproximants. 展开更多
关键词 Nonlinear cervical cancer epidemic non-singular padéapproximants approximate solutions computational biology
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ORTHOGONAL POLYNOMIALS AND DETERMINANT FORMULAS OF FUNCTION-VALUED PADE-TYPE APPROXIMATION USING FOR SOLUTION OF INTEGRAL EQUATIONS 被引量:2
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作者 顾传青 潘宝珍 吴蓓蓓 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第6期853-860,共8页
To solve Fredholm integral equations of the second kind, a generalized linear functional is introduced and a new function-valued Padé-type approximation is defined. By means of the power series expansion of the s... To solve Fredholm integral equations of the second kind, a generalized linear functional is introduced and a new function-valued Padé-type approximation is defined. By means of the power series expansion of the solution, this method can construct an approximate solution to solve the given integral equation. On the basis of the orthogonal polynomials, two useful determinant expressions of the numerator polynomial and the denominator polynomial for Padé-type approximation are explicitly given. 展开更多
关键词 generalized linear functional function-valued padé-type approximation Fredholm integral equation orthogonal polynomial determinant formula
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Least-squares function-valued Padé-type approximation and its application in solving integral equations 被引量:1
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作者 潘宝珍 刘利九 《Journal of Shanghai University(English Edition)》 CAS 2010年第1期66-70,共5页
To solve the Fredholm integral equations of the second kind, a new notion of the least-squares orthogonal polyno- mials of function-valued Pade-type approximation is introduced. On the basis of the error formula, the ... To solve the Fredholm integral equations of the second kind, a new notion of the least-squares orthogonal polyno- mials of function-valued Pade-type approximation is introduced. On the basis of the error formula, the least-squares function: valued Pad&type approximation is constructed. Their existence and uniqueness are studied. A recursive computation formula of the least-squares function-valued Padetype approximation is given. In the end, an example is given to show that the method is effective and stable. 展开更多
关键词 least-squaxes orthogonal polynomial function-valued pade-type approximation Fredholm integral equation
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Function-valued partial Padé-type approximation method for estimating eigenvalues of Fredholm integral equation of the second kind
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作者 顾传青 沈进东 《Journal of Shanghai University(English Edition)》 CAS 2007年第6期531-535,共5页
Abstract A new function-valued partial Padé-type approximation was introduced in the polynomial space, and an explicit determinant formula was derived by means of some orthogonal polynomials. This method can be a... Abstract A new function-valued partial Padé-type approximation was introduced in the polynomial space, and an explicit determinant formula was derived by means of some orthogonal polynomials. This method can be applied to estimating surplus eigenvalues of the Fredholm integral equation of the second kind when its partial eigenvalues have been known, and at the same time, it can be applied to solving the approximating solution of the given equation. 展开更多
关键词 linear functional function-valued partial padé approximation DETERMINANT Fredholm integral equation of thesecond kind eigenvalue.
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Stable Routh-Padé-type approximation in model reduction of interval systems
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作者 顾传青 杨健 《Journal of Shanghai University(English Edition)》 CAS 2010年第5期369-373,共5页
An interval Pade-type approximation is introduced and then Routh-Pade-type method (IRPTM) is presented to model reduction in interval systems. The denominator in reduced model is obtained from the stable Routh table... An interval Pade-type approximation is introduced and then Routh-Pade-type method (IRPTM) is presented to model reduction in interval systems. The denominator in reduced model is obtained from the stable Routh table, and its numerator is constructed by the interval Pade-type definition. Compared to the existing Routh-Pade method, IRPTM does not need to solve linear interval equations theoretical analysis shows that IRPTM has example is given to illustrate our method. Hence, we do not have to compute smaller computational cost than that interval division in the process. Moreover, of Routh-Pade method. A typical numerical 展开更多
关键词 interval system model reduction Routh-table pade-type approximant Routh-pad6-type method
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Computational Aspect For Function-Valued Padé-Type Approximation
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作者 Chuanqing Gu Jindong Shen 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2007年第2期171-180,共10页
The computational problems of two special determinants are investigated. Those determinants appear in the construction of the function-valued Pade-type approximation for computing Fredholm integral equation of the sec... The computational problems of two special determinants are investigated. Those determinants appear in the construction of the function-valued Pade-type approximation for computing Fredholm integral equation of the second kind. The main tool to be used in this paper is the well-known Schur complement theorem. 展开更多
关键词 函数值padé逼近 计算问题 行列式 Schur余角定理
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A New Vector-Valued Padé-Type Approximation in the Inner Space
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作者 Chunjing Li 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第2期127-136,共10页
A new vector-valued Pad′e-type approximation is defined by introducing a gener- alized vector-valued linear functional from a scalar polynomial space to a vector space. Some algebraic properties and error formulas ar... A new vector-valued Pad′e-type approximation is defined by introducing a gener- alized vector-valued linear functional from a scalar polynomial space to a vector space. Some algebraic properties and error formulas are presented. The expressions of this Pad′e-type ap- proximants are provided with the generating function form and the determinant form. 展开更多
关键词 逼近 内部空间 标量多项式空间 向量估计
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The Order of Approximation by Complex Rational Type Interpolating Operators at Fejer's Points 被引量:1
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作者 王子玉 朱长青 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期66-70,共5页
In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the se... In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the sense of uniformly convergence is obtained. 展开更多
关键词 rational type interpolation Fejer's points order of approximation Jordan domain
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THE BERNSTEIN TYPE INEQUALITY AND SIMULTANEOUS APPROXIMATION BY INTERPOLATION POLYNOMIALS IN COMPLEX DOMAIN 被引量:6
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作者 涂天亮 《Acta Mathematica Scientia》 SCIE CSCD 1991年第2期213-220,共8页
In this paper we investigate simultaneous approximation for arbitrary system of nodes on smooth domain in complex plane. Some results which are better than those of known theorems are obtained.
关键词 NODE THE BERNSTEIN type INEQUALITY AND SIMULTANEOUS approximation BY INTERPOLATION POLYNOMIALS IN COMPLEX DOMAIN
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A generalized Padé approximation method of solving homoclinic and heteroclinic orbits of strongly nonlinear autonomous oscillators 被引量:1
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作者 李震波 唐驾时 蔡萍 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期78-84,共7页
An intrinsic extension of Pad′e approximation method, called the generalized Pad′e approximation method, is proposed based on the classic Pad′e approximation theorem. According to the proposed method, the numerator... An intrinsic extension of Pad′e approximation method, called the generalized Pad′e approximation method, is proposed based on the classic Pad′e approximation theorem. According to the proposed method, the numerator and denominator of Pad′e approximant are extended from polynomial functions to a series composed of any kind of function, which means that the generalized Pad′e approximant is not limited to some forms, but can be constructed in different forms in solving different problems. Thus, many existing modifications of Pad′e approximation method can be considered to be the special cases of the proposed method. For solving homoclinic and heteroclinic orbits of strongly nonlinear autonomous oscillators, two novel kinds of generalized Pad′e approximants are constructed. Then, some examples are given to show the validity of the present method. To show the accuracy of the method, all solutions obtained in this paper are compared with those of the Runge–Kutta method. 展开更多
关键词 generalized pad′e approximation method homoclinic and heteroclinic orbits strongly nonlinear oscillators
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Degeneracy Cases of Generalized Inverse Function-Valued Padé Approximation 被引量:1
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作者 潘宝珍 顾传青 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期258-263,共6页
A new generalized inverse function-valued Padé approximation (GIFPA) was defined. Existence condition of GIFPA was given and its uniqueness theorem was proved. All possible degeneracy cases of GIFPA were discusse... A new generalized inverse function-valued Padé approximation (GIFPA) was defined. Existence condition of GIFPA was given and its uniqueness theorem was proved. All possible degeneracy cases of GIFPA were discussed and constructed. An example was given to illustrate its application. 展开更多
关键词 Generalized inverse function-valued padé approximation (GIFPA) degeneracy cases existence and uniqueness.
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A Note on Pad Approximants Pairs as Limits of Algebraic Polynomials Pairs of Weighted Best Approximation in Orlicz Spaces
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作者 F.E.Levis 《Analysis in Theory and Applications》 CSCD 2015年第3期253-259,共7页
In this short note, we show the behavior in Orlicz spaces of best approximations by algebraic polynomials pairs on union of neighborhoods, when the measure of them tends to zero.
关键词 Best approximation pair pad′e approximant pair Orlicz spaces.
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APPROXIMATION OF CONVEX TYPE FUNCTION BY PARTIAL SUMS OF FOURIER SERIES
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作者 YuGuohua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第1期67-76,共10页
The concept of convex type function is introduced in this paper,from which a kin d of convex decomposition approach is proposed.As one of applications of this a pproach,the approximation of the convex type function b... The concept of convex type function is introduced in this paper,from which a kin d of convex decomposition approach is proposed.As one of applications of this a pproach,the approximation of the convex type function by the partial sum of its Fourier series is inves tigated.Moreover,the order of approximation is describe d with the 2th continuous modulus. 展开更多
关键词 Fourier series convex type function CONVEX DECOMPOSITION Riemann deriv ative continuous modulus approximation.
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Asymptotic Property of Approximation to x~αsgnx by Newman Type Operators
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作者 ZHAN QIAN XU SHU-SHENG 《Communications in Mathematical Research》 CSCD 2011年第3期193-199,共7页
The approximation of |x| by rational functions is a classical rationalproblem. This paper deals with the rational approximation of the function xasgnx, which equals |x| if α=1. We construct a Newman type operator... The approximation of |x| by rational functions is a classical rationalproblem. This paper deals with the rational approximation of the function xasgnx, which equals |x| if α=1. We construct a Newman type operator rn(x) and show max|x|≤1{|x^αsgnx-rn(x)|}-Cn-α/2e-√2nα where C is a constant depending on α. 展开更多
关键词 rational approximation asymptotic property Newman type operator
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Approximation by a Complex Post-Widder Type Operator
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作者 Sorin G.Gal Vijay Gupta 《Analysis in Theory and Applications》 CSCD 2018年第4期297-305,共9页
In the present article, we deal with the so-called overconvergence phenomenon in C of a slightly modified Post-Widder operator of real variable, that is with the extension of its approximation properties from the real... In the present article, we deal with the so-called overconvergence phenomenon in C of a slightly modified Post-Widder operator of real variable, that is with the extension of its approximation properties from the real axis in the complex plane.In this sense, error estimates in approximation and a quantitative Voronovskaya-type asymptotic formula are established. 展开更多
关键词 Real and complex Post-Widder type operator overconvergence phenomenon approximation estimate Voronovskaya-type result exact error estimation
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Some Algebraic Properties of Generalized Inverse Matrix-Valued Padé Approximation
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《Advances in Manufacturing》 SCIE CAS 2000年第4期275-278,共4页
关键词 MATH approximation pad Some Algebraic Properties of Generalized Inverse Matrix-Valued
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ON THE UNIFORM STRONG APPROXIMATION OF MARCINKIEWICZ TYPE FOR MULTIVARIABLE CONTINUOUS FUNCTIONS
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作者 Yujun Zhang Xiaoyuan He 《Analysis in Theory and Applications》 2005年第4期377-384,共8页
The rate of uniform strong approzimation of Marcinkiewicz type for multivariable continuous functions is obtained in this paper as follows:‖1/k+1 ^k∑j=0 |Sj(f)-f|^q‖≤C/k+1^k∑j=0 Ej^q(f),where Sj(f) den... The rate of uniform strong approzimation of Marcinkiewicz type for multivariable continuous functions is obtained in this paper as follows:‖1/k+1 ^k∑j=0 |Sj(f)-f|^q‖≤C/k+1^k∑j=0 Ej^q(f),where Sj(f) denotes the square partial Fourier sum off and Ej(f) denotes the square best approximation of f by trigonometric polynomials of degree(j,j,…,j),j=0,1,2.… 展开更多
关键词 square partial Fourier sum strong approximation of Mareinkiewiecz type
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Orthogonal Polynomials and Padé Approximation
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作者 Faiz Ahmad (Department of Mathematics, Quaid i Azam University, Pakistan) 《Advances in Manufacturing》 SCIE CAS 1998年第2期24-27,共4页
The diagonal Padé approximants for exp ( x ), tan x and tanh x are obtained in a simple manner by using the property of Legendre polynomials that on P r1 (x) is orthogonal to every polynomial o... The diagonal Padé approximants for exp ( x ), tan x and tanh x are obtained in a simple manner by using the property of Legendre polynomials that on P r1 (x) is orthogonal to every polynomial of lower degree. Gauss's quadrature formula is used to find the denominators of some functions. 展开更多
关键词 orthogonal polynomials padé approximation
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A SUPER-HALLEY TYPE APPROXIMATION IN BANACH SPACES
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作者 J.A. Ezquerro and M.A. Hernández (University of La Rioja, Spain) 《Analysis in Theory and Applications》 2001年第3期14-25,共12页
The Super-Halley method is one of the best known third-order iteration for solving nonlnear equations. A Newton-like method which is an approximation of this method is studied. Our approach yields a fourth R-order ite... The Super-Halley method is one of the best known third-order iteration for solving nonlnear equations. A Newton-like method which is an approximation of this method is studied. Our approach yields a fourth R-order iterative process which is more efficient than its classical predecessor. We establish a Newton-Kantorovich-type convergence theorem using a new system of recurrence relations, and give an explicit expression for the a priori error bound of the iteration. 展开更多
关键词 A SUPER-HALLEY type approximation IN BANACH SPACES
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APPROXIMATION BY INTEGRAL TYPE MEYER-KONIG-ZELLER OPERATORS ON A SIMPLEX
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作者 Xiong Jingyi and Yang Ruyue(Ningxia University, China) 《Analysis in Theory and Applications》 1997年第1期43-50,共8页
Letbe a simplex in The integral type Meyer-Komg-Zeller operators are constructed on the simplex T, and the degree of approximation of these operators for L'-functions is obtained.
关键词 II approximation BY INTEGRAL type MEYER-KONIG-ZELLER OPERATORS ON A SIMPLEX
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