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MIKUSINSKI'S OPERATORS SOLUTION OF THREE-ORDER LINEAR DIFFERENCE EQUATION WITH VARIABLE COEFFICIENTS
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作者 周之虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第1期71-79,共9页
This paper proceeds the papers [3] [4], we make use of the idea of the variable ,number operators and some concepts and conclusions of the shifting operators serieswith variable coefficients in the operational field o... This paper proceeds the papers [3] [4], we make use of the idea of the variable ,number operators and some concepts and conclusions of the shifting operators serieswith variable coefficients in the operational field of Mikusinski, it is devoted to thesolution of the general three-order linear difference equation with variable,coefficients,and it is also devoted to the better solution .formula for the some special three-orderlinear difference equations with variable coefficients, in addition, we try to provide theidea and method for realizing solution of the more than three-order linear differenceequation with variable coefficients. 展开更多
关键词 mikusinski operator shift operator difference equation
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Properties for Solutions of Nonlinear Functional Difference Equations 被引量:2
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作者 DUANMU Lian-xi 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第3期258-264,共7页
In this paper, some sufficient and necessary conditions are established for the oscillatory of solutions for nonlinear functional difference equations, which extend and improve some corresponding results obtained and ... In this paper, some sufficient and necessary conditions are established for the oscillatory of solutions for nonlinear functional difference equations, which extend and improve some corresponding results obtained and are discrete analogues of the corresponding results for the continuous version. 展开更多
关键词 functional difference equation OSCILLATION increasing operator fixed point theorem
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Positive Solutions of p-Laplacian Functional Difference Equations 被引量:1
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作者 SONG Chang-xiu 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第4期475-481,共7页
In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the p... In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the positive solutions. 展开更多
关键词 p-Laplacian operator functional difference equations positive solution CONE
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HOMOCLINIC SOLUTIONS OF NONLINEAR LAPLACIAN DIFFERENCE EQUATIONS WITHOUT AMBROSETTI-RABINOWITZ CONDITION
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作者 Antonella NASTASI Stepan TERSIAN Calogero VETRO 《Acta Mathematica Scientia》 SCIE CSCD 2021年第3期712-718,共7页
The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mo... The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mountain pass theorem and Palais-Smale compactness condition involving suitable functionals. 展开更多
关键词 difference equations homoclinic solutions non-zero solutions (p q)-Laplacian operator
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SOLUTIONS OF THE GENERALn-TH ORDER VARIABLE COEFFICIENTS LINEAR DIFFERENCE EQUATION
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作者 周之虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第3期235-246,共12页
In this paper.variable operator and its product with shifting operator are studied.The product of power series of shifting operator with variable coefficient is defined andits convergence is proved under Mikusinski’s... In this paper.variable operator and its product with shifting operator are studied.The product of power series of shifting operator with variable coefficient is defined andits convergence is proved under Mikusinski’s sequence convergence.After turning ageneral variable coefficient linear difference equation of order n into a set of operatorequations.we can obtain the solutions of the general n-th order variable coefficientlinear difference equation. 展开更多
关键词 mikusinskis operator. variable operator. convergence. lineardifference equation with variable coefficients. solution of seriesform. operator equation
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Discrete Pseudo Almost Periodic Solutions for Some Difference Equations
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作者 Elhadi Ait Dads Khalil Ezzinbi Lahcen Lhachimi 《Advances in Pure Mathematics》 2011年第4期118-127,共10页
In this work, we study the existence and uniqueness of pseudo almost periodic solutions for some difference equations. Firstly, we investigate the spectrum of the shift operator on the space of pseudo almost periodic ... In this work, we study the existence and uniqueness of pseudo almost periodic solutions for some difference equations. Firstly, we investigate the spectrum of the shift operator on the space of pseudo almost periodic sequences to show the main results of this work. For the illustration, some applications are provided for a second order differential equation with piecewise constant arguments. 展开更多
关键词 difference equationS PSEUDO ALMOST Periodic SEQUENCES Schift operator
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ENTIRE FUNCTIONS SHARING ONE SMALL FUNCTION CM WITH THEIR SHIFTS AND DIFFERENCE OPERATORS 被引量:3
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作者 崔宁 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期786-798,共13页
In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of ... In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of finite order, c be a nonzero finite complex constant, and n be a positive integer. If f(z), f(z+c), and △n cf(z) share 0 CM, then f(z+c)≡Af(z), where A(≠0) is a complex constant. Moreover, let a(z), b(z)( O) ∈ S(f) be periodic entire functions with period c and if f(z) - a(z), f(z + c) - a(z), △cn f(z) - b(z) share 0 CM, then f(z + c) ≡ f(z). 展开更多
关键词 Entire function shiftS difference operators shared values
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Optimization of the seismic processing phase-shift plus finite-difference migration operator based on a hybrid genetic and simulated annealing algorithm 被引量:2
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作者 Luo Renze Huang Yuanyi +2 位作者 Liang Xianghao Luo Jun Cao Ying 《Petroleum Science》 SCIE CAS CSCD 2013年第2期190-194,共5页
Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome... Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome this defect, a finite-difference method in the frequency-space domain is introduced in the migration process, because it can adapt to strong lateral velocity variation and the coefficient is optimized by a hybrid genetic and simulated annealing algorithm. The two measures improve the precision of the approximation dispersion equation. Thus, the imaging effect is improved for areas of high-dip structure and strong lateral velocity variation. The migration imaging of a 2-D SEG/EAGE salt dome model proves that a better imaging effect in these areas is achieved by optimized phase-shift migration operator plus a finite-difference method based on a hybrid genetic and simulated annealing algorithm. The method proposed in this paper is better than conventional methods in imaging of areas of high-dip angle and strong lateral velocity variation. 展开更多
关键词 Migration operator phase-shift plus finite-difference hybrid algorithm genetic andsimulated annealing algorithm optimization coefficient
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On Invertibility of Some Functional Operators with Shift
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作者 Aleksandr Karelin Anna Tarasenko Manuel Gonzalez-Hernandez 《Applied Mathematics》 2022年第8期651-657,共7页
In this paper, we consider operators arising in the modeling of renewable systems with elements that can be in different states. These operators are functional operators with non-Carlemann shifts and they act in Holde... In this paper, we consider operators arising in the modeling of renewable systems with elements that can be in different states. These operators are functional operators with non-Carlemann shifts and they act in Holder spaces with weight. The main attention was paid to non-linear equations relating coefficients to operators with a shift. The solutions of these equations were used to reduce the operators under consideration to operators with shift, the invertibility conditions for which were found in previous articles of the authors. To construct the solution of the non-linear equation, we consider the coefficient factorization problem (the homogeneous equation with a zero right-hand side) and the jump problem (the non-homogeneous equation with a unit coefficient). The solution of the general equation is represented as a composition of the solutions to these two problems. 展开更多
关键词 operator with a Non-Carlemann shift Inverse operator Non-Linear equation Factorization of Coefficient equation with Unit Coefficient
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Meromorphic Functions of Finiteφ-order and Linear Askey-Wilson Divided Difference Equations 被引量:1
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作者 Hui YU Janne HEITTOKANGAS +1 位作者 Jun WANG Zhi Tao WEN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2022年第2期371-383,共13页
The growth of meromorphic solutions of linear difference equations containing Askey-Wilson divided difference operators is estimated.Theφ-order is used as a general growth indicator,which covers the growth spectrum b... The growth of meromorphic solutions of linear difference equations containing Askey-Wilson divided difference operators is estimated.Theφ-order is used as a general growth indicator,which covers the growth spectrum between the logarithmic orderρlog(f)and the classical orderρ(f)of a meromorphic function f. 展开更多
关键词 Askey-Wilson divided difference operator Askey-Wilson divided difference equation lemma on the logarithmic
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Discrete Heat Equation Model with Shift Values
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作者 G. Britto Antony Xavier S. John Borg M. Meganathan 《Applied Mathematics》 2017年第9期1343-1350,共8页
We investigate the generalized partial difference operator and propose a model of it in discrete heat equation in this paper. The diffusion of heat is studied by the application of Newton’s law of cooling in dimensio... We investigate the generalized partial difference operator and propose a model of it in discrete heat equation in this paper. The diffusion of heat is studied by the application of Newton’s law of cooling in dimensions up to three and several solutions are postulated for the same. Through numerical simulations using MATLAB, solutions are validated and applications are derived. 展开更多
关键词 Generalized PARTIAL difference equation PARTIAL difference operator and DISCRETE Heat equation
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Propagation and Pinning of Travelling Wave for Nagumo Type Equation
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作者 Sharon-Yasotha Veerayah-Mcgregor Valipuram Manoranjan 《Journal of Applied Mathematics and Physics》 2024年第3期861-869,共9页
In this paper, we study the propagation and its failure to propagate (pinning) of a travelling wave in a Nagumo type equation, an equation that describes impulse propagation in nerve axons that also models population ... In this paper, we study the propagation and its failure to propagate (pinning) of a travelling wave in a Nagumo type equation, an equation that describes impulse propagation in nerve axons that also models population growth with Allee effect. An analytical solution is derived for the traveling wave and the work is extended to a discrete formulation with a piecewise linear reaction function. We propose an operator splitting numerical scheme to solve the equation and demonstrate that the wave either propagates or gets pinned based on how the spatial mesh is chosen. 展开更多
关键词 operator Splitting Travelling Wave Piecewise Reaction Nagumo equation PINNING Finite differences
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无穷区间上带p-Laplacian算子的分数阶q-差分方程的迭代正解 被引量:1
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作者 王菊芳 张金叶 禹长龙 《河北科技大学学报》 北大核心 2025年第2期175-185,共11页
为了丰富分数阶q-差分方程边值问题的基本理论,研究了一类无穷区间上带p-Laplacian算子的非线性分数阶q-差分方程边值问题。首先,计算线性分数阶q-差分方程边值问题的Green函数并研究其性质;其次,引入无穷区间上的紧性判定准则并在抽象... 为了丰富分数阶q-差分方程边值问题的基本理论,研究了一类无穷区间上带p-Laplacian算子的非线性分数阶q-差分方程边值问题。首先,计算线性分数阶q-差分方程边值问题的Green函数并研究其性质;其次,引入无穷区间上的紧性判定准则并在抽象空间上构造积分算子;再次,选取初值函数,运用单调迭代技巧,获得边值问题正解的存在性;最后,通过实例验证所得结果的有效性。结果表明,在赋予非线性项f一定的增长条件下,通过构造迭代序列,可得到分数阶q-差分方程的最大和最小正解。研究结果拓展了已有的相关结论,为分数阶q-差分方程在数学、物理等领域的进一步应用提供了理论参考。 展开更多
关键词 非线性泛函分析 分数阶q-差分方程 P-LAPLACIAN算子 单调迭代技巧 无穷区间
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三帧差法和Mean-shift结合的行人检测与跟踪研究 被引量:14
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作者 姚倩 安世全 姚路 《计算机工程与设计》 CSCD 北大核心 2014年第1期223-227,共5页
为了快速、准确地对视频序列中的行人进行检测和跟踪,提出了一种基于运动区域的Mean-shift行人检测和跟踪算法。采用改进的背景差分的三帧间差分法对运动区域进行提取,并通过离线训练的HOG分类器对行人进行识别。提出采用基于Mean-shif... 为了快速、准确地对视频序列中的行人进行检测和跟踪,提出了一种基于运动区域的Mean-shift行人检测和跟踪算法。采用改进的背景差分的三帧间差分法对运动区域进行提取,并通过离线训练的HOG分类器对行人进行识别。提出采用基于Mean-shift的轮廓跟踪算法对行人进行实时跟踪。实验结果表明,该算法能够将不包含行人信息的区域进行筛选排除,在不降低检测效果的情况下明显提高了行人检测及跟踪的效率,具有较强的鲁棒性。 展开更多
关键词 三帧差法 MEAN-shift 背景差分法 HOG算子 支持向量机
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二阶变系数线性差分方程的Mikusinski算符解法 被引量:3
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作者 周之虎 《应用数学》 CSCD 北大核心 1994年第4期460-464,共5页
本文利用Mikusinski算符域中变数算符的概念和相应的变系数移动算符幂级数的概念和结果,成功地获得二阶变系数线性差分方程的解。
关键词 变数算符 线性 差分方程 M算符
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Finite-difference time-domain studies of low-frequency stop band in superconductor-dielectric superlattice 被引量:1
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作者 王身云 刘少斌 Le-Wei Joshua Li 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期374-378,共5页
The transmission coefficients of electromagnetic (EM) waves due to a superconductor-dielectric superlattice are numerically calculated. Shift operator finite difference time domain (SO-FDTD) method is used in the ... The transmission coefficients of electromagnetic (EM) waves due to a superconductor-dielectric superlattice are numerically calculated. Shift operator finite difference time domain (SO-FDTD) method is used in the analysis. By using the SO-FDTD method, the transmission spectrum is obtained and its characteristics are investigated for different thicknesses of superconductor layers and dielectric layers, from which a stop band starting from zero frequency can be apparently observed. The relation between this low-frequency stop band and relative temperature, and also the London penetration depth at a superconductor temperature of zero degree are discussed, separately. The low-frequency stop band properties of superconductor-dielectric superlattice thus are well disclosed. 展开更多
关键词 shift operator finite difference time domain method SUPERCONDUCTOR superconductor- dielectric superlattice high-pass filter
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基于傅里叶神经算子的电磁智能计算研究
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作者 赵洁 周东华 +2 位作者 冯健 方明 黄志祥 《现代应用物理》 2025年第1期170-174,211,共6页
在电磁应用研究中,求解麦克斯韦方程组是关键步骤。深度学习(deep learning,DL)作为一种新兴且前景广阔的技术,凭借强大的数据驱动建模能力,已逐渐成为解决偏微分方程(partial differential equation,PDE)的一种有效方法。通过神经网络... 在电磁应用研究中,求解麦克斯韦方程组是关键步骤。深度学习(deep learning,DL)作为一种新兴且前景广阔的技术,凭借强大的数据驱动建模能力,已逐渐成为解决偏微分方程(partial differential equation,PDE)的一种有效方法。通过神经网络实现输入数据对输出的直接映射从而解决电磁问题。本文中使用的傅里叶神经算子(Fourier neural operator,FNO)是通过直接学习从参数到PDE解的映射,并在傅里叶空间中离散化PDE,从而实现对PDE求解。本文将FNO应用于麦克斯韦方程,以此来求解2维情况下的复杂电磁问题。与传统的数值算法相比,FNO的计算速度快了2个量级,为处理2维情况下的复杂电磁问题提供了新的视角和工具。 展开更多
关键词 傅里叶神经算子 偏微分方程 时域有限差分法
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n阶变系数线性常微分方程的Mikusinski算符近似算法 被引量:1
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作者 周之虎 《安徽建筑工业学院学报(自然科学版)》 2000年第2期1-3,共3页
利用 J.Mikusinski的算符演算理论和变数算符概念 ,给出半直线上
关键词 线性常微分方程 变系数 变数算符 半直线 近似算法 演算 连续型 算理 概念 理论
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四阶线性变系数差分方程的Mikusinski算符解法 被引量:1
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作者 周之虎 《哈尔滨科学技术大学学报》 1994年第2期78-86,共9页
在Mikusinski创立的算符域中引入变数算符,由此改进了原算符的结构和相应的代数运算体系,并以此为工具研究求解变系数方程问题,获得了四阶变系数差分方程的解。
关键词 线性 变系数 差分方程 算符解法
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Bellman Equation for Optimal Processes with Nonlinear Multi-Parametric Binary Dynamic System
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作者 Yakup H. Hacl Kemal Ozen 《Computer Technology and Application》 2012年第1期84-87,共4页
A process represented by nonlinear multi-parametric binary dynamic system is investigated in this work. This process is characterized by the pseudo Boolean objective functional. Since the transfer functions on the pro... A process represented by nonlinear multi-parametric binary dynamic system is investigated in this work. This process is characterized by the pseudo Boolean objective functional. Since the transfer functions on the process are Boolean functions, the optimal control problem related to the process can be solved by relating between the transfer functions and the objective functional. An analogue of Bellman function for the optimal control problem mentioned is defined and consequently suitable Bellman equation is constructed. 展开更多
关键词 Bellman equation bellman function galois field shift operator nonlinear multi-parametric binary dynamic system
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