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Stable computations of the spherically layered media theory with high lossy media by using scaled Bessel functions
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作者 Jia-Hui Wang Bo O.Zhu 《Journal of Electronic Science and Technology》 2025年第1期22-34,共13页
The spherically layered media theory has wide applications for electromagnetic wave scattering analysis.Due to the involved Bessel functions,the conventional formulations of spherically layered media theory suffer fro... The spherically layered media theory has wide applications for electromagnetic wave scattering analysis.Due to the involved Bessel functions,the conventional formulations of spherically layered media theory suffer from numerical overflow or underflow when the Bessel function’s order is large,the argument is small or the argument has a large imaginary part.The first two issues have been solved recently by employing small-argument asymptotic formulas of Bessel functions,while the third issue remains unsolved.In this paper,the Bessel functions in the conventional formulation of the theory are replaced by scaled Bessel functions which have good numerical properties for high loss media,and stable formulas are derived.Numerical tests show that this approach can work properly with very high lossy media.Also,this approach can be seamlessly combined with the stable computation method for cases of small argument and large order of Bessel functions. 展开更多
关键词 Lossy media Numerical stability Scaled bessel function Spherically layered media theory
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Normalized Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan XU Liping 《应用数学》 北大核心 2025年第1期14-29,共16页
In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with ... In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with prescribed 2-norm has some normalized solutions by introducing variational methods. 展开更多
关键词 Nonlinear Choquard equation Potential function Variational method Normalized solution
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Existence of Periodic Solutions for Generalized Liénard-Typed Functional Differential Equations
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作者 贺小明 葛渭高 单文锐 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期325-328,共4页
The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are ... The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are established for the existence of periodic solutions and some previous results are extended. 展开更多
关键词 functional differential equation periodic solution coincidence degree
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The Global Solutions of Impulsive Retarded Functional Differential Equations
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作者 王儒智 孙建安 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期94-99,共6页
In this paper, we present some results on the existence of the golbal solutions of nonlinear impulsive retarded functional differential equations.
关键词 Fréchet spaces Tychonoff fixed point Theorem impulsive retarded functional differential equations
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THE BASIC THEORY OF SOLUTIONS OF FUNCTIONAL DIFFERENTIAL EQUATIONS WITH BOUNDED DELAY IN THE SPACE OF INTEGRABLE FUNCTIONS
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作者 刘永清 李远清 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 1997年第7期67-73,共7页
在可积函数空间中讨论有界滞量泛函微分方程,建立其解的基本理论,包括解的存在性,唯一性及延展性。
关键词 有界滞量的泛函微分方程 存在性 唯一性 延展性 可积函数空间
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AN OSCILLATION CRITERIA FOR SECOND ORDERFUNCTIONAL EQUATIONS 被引量:14
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作者 申建华 IP. Stavroulakis 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期56-62,共7页
This paper is concerned with the oscillation of second order linear functional equations of the form x(g(t)) = p(t)x(t) + Q(t)X(g(2)(t)), Where p, Q, g : [t(0), infinity) --> R+ = [0, infinity) are given real value... This paper is concerned with the oscillation of second order linear functional equations of the form x(g(t)) = p(t)x(t) + Q(t)X(g(2)(t)), Where p, Q, g : [t(0), infinity) --> R+ = [0, infinity) are given real valued functions such that g(t) not equivalent to t, lim(t-->infinity) g(t) = infinity. It is proved here that when 0 less than or equal to m := lim inf(t-->infinity) Q(t)P(g(t)) less than or equal to 1/4 all solutions of this equation oscillate if the condition lim(t-->infinity) sup Q(t)P(g(t)) > (1 + root1 -4m/2)(2) (*) is satisfied. It should be emphasized that the condition (*) can not be improved in some sense. 展开更多
关键词 OSCILLATION NONOSCILLATION functional equations
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ON MEROMORPHIC SOLUTIONS OF A TYPE OF SYSTEM OF COMPOSITE FUNCTIONAL EQUATIONS 被引量:12
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作者 高凌云 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期800-806,共7页
In this article, we mainly investigate the growth and existence of meromorphic solutions of a type of systems of composite functional equations, and obtain some interesting results. It extends some results concerning ... In this article, we mainly investigate the growth and existence of meromorphic solutions of a type of systems of composite functional equations, and obtain some interesting results. It extends some results concerning functional equations to the systems of functional equations. 展开更多
关键词 meromorphic solution composite function functional equations
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Some new exact solutions of Jacobian elliptic function about the generalized Boussinesq equation and Boussinesq-Burgers equation 被引量:9
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作者 张亮 张立凤 李崇银 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期403-410,共8页
By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic functio... By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic function solutions, combined Jacobian elliptic function solutions, soliton solutions, triangular function solutions. 展开更多
关键词 generalized Boussinesq equation Boussinesq-Burgers equation Jacobian elliptic function modified mapping method
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ON DIFFERENCE EQUATIONS RELATING TO GAMMA FUNCTION 被引量:8
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作者 陈宗煊 黄志波 张然然 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1281-1294,共14页
We consider the existence, the growth, poles, zeros, fixed points and the Borel exceptional value of solutions for the following difference equations relating to Gamma function y(z + 1) -y(z) = R(z) and y(z ... We consider the existence, the growth, poles, zeros, fixed points and the Borel exceptional value of solutions for the following difference equations relating to Gamma function y(z + 1) -y(z) = R(z) and y(z + 1) = P (z)y(z). 展开更多
关键词 difference equation meromorphic function Borel exceptional value
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Construction of doubly-periodic solutions to nonlinear partial differential equations using improved Jacobi elliptic function expansion method and symbolic computation 被引量:7
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作者 赵雪芹 智红燕 张鸿庆 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2202-2209,共8页
Some doubly-periodic solutions of the Zakharov-Kuznetsov equation are presented. Our approach is to introduce an auxiliary ordinary differential equation and use its Jacobi elliptic function solutions to construct dou... Some doubly-periodic solutions of the Zakharov-Kuznetsov equation are presented. Our approach is to introduce an auxiliary ordinary differential equation and use its Jacobi elliptic function solutions to construct doubly-periodic solutions of the Zakharov-Kuznetsov equation, which has been derived by Gottwald as a two-dimensional model for nonlinear Rossby waves. When the modulus k →1, these solutions reduce to the solitary wave solutions of the equation. 展开更多
关键词 Jacobi elliptic function method doubly-periodic solutions Zakharov-Kuznetsov equation
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RAZUMIKHIN-TYPE THEOREM FOR NEUTRAL STOCHASTIC FUNCTIONAL DIFFERENTIAL EQUATIONS WITH UNBOUNDED DELAY 被引量:6
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作者 吴付科 胡适耕 毛学荣 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1245-1258,共14页
This paper establishes the Razumikhin-type theorem on stability for neutral stochastic functional differential equations with unbounded delay. To overcome difficulties from unbounded delay, we develop several differen... This paper establishes the Razumikhin-type theorem on stability for neutral stochastic functional differential equations with unbounded delay. To overcome difficulties from unbounded delay, we develop several different techniques to investigate stability. To show our idea clearly, we examine neutral stochastic delay differential equations with unbounded delay and linear neutral stochastic Volterra unbounded-delay-integro-differential equations. 展开更多
关键词 neutral stochastic functional differential equations Razumikhin-type theorem ψ γ stability exponential stability polynomial stability
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ON SOME RESULTS OF YI AND THEIR APPLICATIONS IN THE FUNCTIONAL EQUATIONS 被引量:3
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作者 杨连中 张继龙 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1649-1660,共12页
In this article, we establish some uniqueness theorems that improves some results of H. X. Yi for a family of meromorphic functions, and as applications, we give some results about the non-existence of meromorphic sol... In this article, we establish some uniqueness theorems that improves some results of H. X. Yi for a family of meromorphic functions, and as applications, we give some results about the non-existence of meromorphic solutions of Fermat type functional equations. 展开更多
关键词 functional equations meromorphic functions UNIQUENESS
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APPROXIMATION OF A CAUCHY-JENSEN ADDITIVE FUNCTIONAL EQUATION IN NON-ARCHIMEDEAN NORMED SPACES 被引量:3
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作者 Hassan Azadi Kenary 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2247-2258,共12页
Using the fixed point and direct methods, we prove the Hyers-Ulam stability of the following Cauchy-Jensen additive functional equation 2f(p∑i=1xi+q∑j=1yj+2d∑k=1zk/2)=p∑i=1f(xi)+q∑j=1f(yj)+2d∑k=1f(zk... Using the fixed point and direct methods, we prove the Hyers-Ulam stability of the following Cauchy-Jensen additive functional equation 2f(p∑i=1xi+q∑j=1yj+2d∑k=1zk/2)=p∑i=1f(xi)+q∑j=1f(yj)+2d∑k=1f(zk),where p, q, d are integers greater than 1, in non-Archimedean normed spaces. 展开更多
关键词 Hyers-Ulam stability Cauchy-Jensen additive functional equation fixedpoint non-Archimedean normed spaces
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The derivative-dependent functional variable separation for the evolution equations 被引量:3
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作者 张顺利 楼森岳 屈长征 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2765-2776,共12页
This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which adm... This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which admits the derivative- dependent functional separable solutions (DDFSSs). We also extend the concept of the DDFSS to cover other variable separation approaches. 展开更多
关键词 derivative-dependent functional variable separation evolution equations generalized conditional symmetry
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Birkhoffian Formulations of Bessel Equation 被引量:1
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作者 Wen'an Jiang Lili Xia Yanli Xu 《Journal of Beijing Institute of Technology》 EI CAS 2019年第2期234-237,共4页
The Birkhoffian mechanics is more general than the Hamilton mechanics,but only some dynamical systems can be realized as a Birkhoffian formulation.This paper proposes a novel Birkhoffian formulation for the classical ... The Birkhoffian mechanics is more general than the Hamilton mechanics,but only some dynamical systems can be realized as a Birkhoffian formulation.This paper proposes a novel Birkhoffian formulation for the classical Bessel equation.Based on the first method of Santilli,the Birkhoffian formulation of Bessel equation is established under the assumption that the Birkhoffian describes the total physical energy of the corresponding conservative systems.Zero and n-th order classical Bessel equations are studied to verify the effectiveness of the proposed formulation. 展开更多
关键词 BIRKHOFFIAN formulations bessel equation FIRST METHOD of Santilli
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Existence of asymptotically almost periodic solutions and stability properties for functional difference equations 被引量:4
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作者 吴中华 《Journal of Chongqing University》 CAS 2012年第2期97-102,共6页
For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain li... For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain limiting equation. 展开更多
关键词 functional difference equations asymptotically almost periodic solutions total stability properties
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An extended functional transformation method and its application in some evolution equations 被引量:2
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作者 丁海勇 徐西祥 杨宏祥 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第9期1687-1690,共4页
In this paper, an extended functional transformation is given to solve some nonlinear evolution equations. This function, in fact, is a solution of the famous KdV equation, so this transformation gives a transformatio... In this paper, an extended functional transformation is given to solve some nonlinear evolution equations. This function, in fact, is a solution of the famous KdV equation, so this transformation gives a transformation between KdV equation and other soliton equations. Then many new exact solutions can be given by virtue of the solutions of KdV equation. 展开更多
关键词 extended functional transformation exact solution KdV equation
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THIRD-ORDER DIFFERENTIAL SUBORDINATION RESULTS FOR ANALYTIC FUNCTIONS INVOLVING THE GENERALIZED BESSEL FUNCTIONS 被引量:4
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作者 汤获 Erhan DENIZ 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1707-1719,共13页
In the present paper, we derive some third-order differential subordination results for analytic functions in the open unit disk, using the operator Bcκf by means of normalized form of the generalized Bessel function... In the present paper, we derive some third-order differential subordination results for analytic functions in the open unit disk, using the operator Bcκf by means of normalized form of the generalized Bessel functions of the first kind, which is defined as z(Bκ+1^c f(z))′= κBκ^c f(z)-(κ- 1)Bκ+1^c f(z),where b, c, p ∈ C and κ = p +(b + 1)/2 ∈ C / Z0^-(Z0^-= {0,-1,-2, … }). The results are obtained by considering suitable classes of admissible functions. Various known or new special cases of our main results are also pointed out. 展开更多
关键词 differential subordination univalent functions Hadamard product admissible functions generalized bessel functions
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RANDOM APPROXIMATION OF AN ADDITIVE FUNCTIONAL EQUATION OF m-APPOLLONIUS TYPE 被引量:2
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作者 Hassan Azadi Kenary 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1813-1825,共13页
In this paper,using the fixed-point and direct methods,we prove the HyersUlam stability of the following m-Appolonius type functional equation:∑mi=1 f(z-xi)=mf(z-1/m2∑mi=1xi)-1/m∑1≤i〈j≤mf(xi+xj),where m ... In this paper,using the fixed-point and direct methods,we prove the HyersUlam stability of the following m-Appolonius type functional equation:∑mi=1 f(z-xi)=mf(z-1/m2∑mi=1xi)-1/m∑1≤i〈j≤mf(xi+xj),where m is a natural number greater than 1,in random normed spaces. 更多还原 展开更多
关键词 Hyers-Ulam stability additive functional equation random normed space fixed point method
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Trial function method and exact solutions to the generalized nonlinear Schrdinger equation with time-dependent coefficient 被引量:2
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作者 曹瑞 张健 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期182-185,共4页
In this paper, the trial function method is extended to study the generalized nonlinear Schrodinger equation with time- dependent coefficients. On the basis of a generalized traveling wave transformation and a trial f... In this paper, the trial function method is extended to study the generalized nonlinear Schrodinger equation with time- dependent coefficients. On the basis of a generalized traveling wave transformation and a trial function, we investigate the exact envelope traveling wave solutions of the generalized nonlinear Schrodinger equation with time-dependent coefficients. Taking advantage of solutions to trial function, we successfully obtain exact solutions for the generalized nonlinear Schrodinger equation with time-dependent coefficients under constraint conditions. 展开更多
关键词 generalized nonlinear SchriSdinger equation exact solution trial function method
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