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ON THE RATES OF CONVERGENCE IN THE CENTRAL LIMIT THEOREM FOR TWO-PARAMETER MARTINGALE DIFFERENCES
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作者 龙红卫 《Acta Mathematica Scientia》 SCIE CSCD 1996年第3期287-295,共9页
In this paper we obtain the uniform bounds on the rate of convergence in the central limit theorem (CLT) for a class of two-parameter martingale difference sequences under certain conditions.
关键词 noncomplete half-plane martingale difference central limit theorem rates of convergence uniform bound
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Star-shaped Differentiable Functions and Star-shaped Differentials
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作者 PAN SHAO-RONG ZHANG HONG-WEI ZHANG LI-WEI 《Communications in Mathematical Research》 CSCD 2010年第1期41-52,共12页
Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defin... Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defined. Formulas for star-shaped differential of a pointwise maximum and a pointwise minimum of a finite number of directionally differentiable functions, and a composite of two directionaUy differentiable functions are derived. Furthermore, the mean-value theorem for a directionaUy differentiable function is demonstrated. 展开更多
关键词 The space of star-shaped sets gauge function isometrical isomorphism directionally differentiable function star-shaped differential mean-value theorem
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New Asymptotical Stability and Uniformly Asymptotical Stability Theorems for Nonautonomous Difference Equations
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作者 Limin Zhang Chaofeng Zhang 《Applied Mathematics》 2016年第10期1023-1031,共9页
New theorems of asymptotical stability and uniformly asymptotical stability for nonautonomous difference equations are given in this paper. The classical Liapunov asymptotical stability theorem of nonautonomous differ... New theorems of asymptotical stability and uniformly asymptotical stability for nonautonomous difference equations are given in this paper. The classical Liapunov asymptotical stability theorem of nonautonomous difference equations relies on the existence of a positive definite Liapunov function that has an indefinitely small upper bound and whose variation along a given nonautonomous difference equations is negative definite. In this paper, we consider the case that the Liapunov function is only positive definite and its variation is semi-negative definite. At these weaker conditions, we put forward a new asymptotical stability theorem of nonautonomous difference equations by adding to extra conditions on the variation. After that, in addition to the hypotheses of our new asymptotical stability theorem, we obtain a new uniformly asymptotical stability theorem of nonautonomous difference equations provided that the Liapunov function has an indefinitely small upper bound. Example is given to verify our results in the last. 展开更多
关键词 Nonautonomous difference Equations New Asymptotical Stability theorem New Uniformly Asymptotical Stability theorem Liapunovs Direct Method
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Feynman Formulas Representation of Semigroups Generated by Parabolic Difference-Differential Equations
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作者 V. Sakbaev A. Yaakbarieh 《American Journal of Computational Mathematics》 2012年第4期295-301,共7页
We establish that the Laplas operator with perturbation by symmetrised linear hall of displacement argument operators is the generator of unitary group in the Hilbert space of square integrable functions. The represen... We establish that the Laplas operator with perturbation by symmetrised linear hall of displacement argument operators is the generator of unitary group in the Hilbert space of square integrable functions. The representation of semigroup of Cauchy problem solutions for considered functional differential equation is given by the Feynman formulas. 展开更多
关键词 difference-differential Equations SEMIGROUP FEYNMAN Formula Chernoff theorem
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ON PROPERTIES OF DIFFERENCE POLYNOMIALS 被引量:6
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作者 陈宗煊 黄志波 郑秀敏 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期627-633,共7页
We study the value distribution of difference polynomials of meromorphic functions, and extend classical theorems of Tumura-Clunie type to difference polynomials. We also consider the value distribution of f(z)f(z ... We study the value distribution of difference polynomials of meromorphic functions, and extend classical theorems of Tumura-Clunie type to difference polynomials. We also consider the value distribution of f(z)f(z + c). 展开更多
关键词 difference polynomial Tumura-Clunie theorem value distribution.
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RITT-WU'S CHARACTERISTIC SET METHOD FOR ORDINARY DIFFERENCE POLYNOMIAL SYSTEMS WITH ARBITRARY ORDERING 被引量:6
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作者 高小山 袁春明 张桂林 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1063-1080,共18页
In this paper, a Ritt-Wu's characteristic set method for ordinary difference systems is proposed, which is valid for any admissible ordering. New definition for irreducible chains and new zero decomposition algorithm... In this paper, a Ritt-Wu's characteristic set method for ordinary difference systems is proposed, which is valid for any admissible ordering. New definition for irreducible chains and new zero decomposition algorithms are also proposed. 展开更多
关键词 difference polynomial ascending chain characteristic set Ritt-Wu's zero decomposition theorem
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Force analysis of pile foundation in rock slope based on upper-bound theorem of limit 被引量:13
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作者 赵明华 刘建华 +1 位作者 刘代全 汪优 《Journal of Central South University of Technology》 EI 2008年第3期404-410,共7页
Based on the characteristic that the potential sliding surfaces of rock slope are commonly in the shape of either line or fold line,analysis thought of conventional pile foundation in the flat ground under complex loa... Based on the characteristic that the potential sliding surfaces of rock slope are commonly in the shape of either line or fold line,analysis thought of conventional pile foundation in the flat ground under complex load condition was applied and the upper-bound theorem of limit analysis was used to compute thrust of rock layers with all possible distribution shapes. The interaction of slope and pile was considered design load in terms of slope thrust,and the finite difference method was derived to calculate inner-force and displacement of bridge pile foundation in rock slope under complex load condition. The result of example shows that the distribution model of slope thrust has certain impact on displacement and inner-force of bridge pile foundation. The maximum displacement growth rate reaches 54% and the maximum moment and shear growth rates reach only 15% and 20%,respectively,but the trends of inner-force and displacement of bridge pile foundation are basically the same as those of the conventional pile foundation in the flat ground. When the piles bear the same level lateral thrust,the distribution shapes of slope thrust have different influence on inner-force of pile foundation,especially the rectangle distribution,and the triangle thrust has the smallest displacement and inner-force of pile foundation. 展开更多
关键词 pile foundation rock slope inner-force calculation finite difference method upper-bound theorem of limit analysis
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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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Existence of Three Positive Periodic Solutions of Neutral Nonlinear Functional Difference Equations 被引量:1
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作者 LIU Xing-yuan 《Chinese Quarterly Journal of Mathematics》 2015年第2期172-183,共12页
This paper is concerned with the nonlinear neutral functional difference equations△x(n) =-a(n)x(n) +h(n)f(n,x(n-T(n)),△x(n-δ(n))),where a,h and f are nonnegative sequences.Sufficient conditions for the existence of... This paper is concerned with the nonlinear neutral functional difference equations△x(n) =-a(n)x(n) +h(n)f(n,x(n-T(n)),△x(n-δ(n))),where a,h and f are nonnegative sequences.Sufficient conditions for the existence of at least three positive T-periodic solutions are established by using a fixed point theorem due to Avery and Peterson. 展开更多
关键词 positive periodic solution functional difference equation fixed-point theorem
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Existence and Multiple of Positive Solution for Nonlinear Fractional Difference Equations with Parameter 被引量:1
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作者 Youji Xu 《Journal of Applied Mathematics and Physics》 2015年第7期757-760,共4页
Let,. We study the existence and multiple positive solutions of n-th nonlinear discrete fractional boundary value problem of the form By using a fixed-point theorem on cone, the parameter intervals of problem is estab... Let,. We study the existence and multiple positive solutions of n-th nonlinear discrete fractional boundary value problem of the form By using a fixed-point theorem on cone, the parameter intervals of problem is established. 展开更多
关键词 Fractional difference Equations PARAMETER INTERVALS Positive Solution FIXED-POINT theorem
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Existence of Positive Solutions for Boundary Value Problem of Nonlinear Fractional <i>q</i>-Difference Equation 被引量:9
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作者 Liu Yang 《Applied Mathematics》 2013年第10期1450-1454,共5页
In this paper, we investigate the existence of positive solutions for a class of nonlinear q-fractional boundary value problem. By using some fixed point theorems on cone, some existence results of positive solutions ... In this paper, we investigate the existence of positive solutions for a class of nonlinear q-fractional boundary value problem. By using some fixed point theorems on cone, some existence results of positive solutions are obtained. 展开更多
关键词 Fractional q-difference Equation Positive Solution Fixed Point theoremS on Cone
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EXACT EVALUATIONS OF FINITE TRIGONOMETRIC SUMS BY SAMPLING THEOREMS
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作者 M.H. Annaby R.M. Asharabi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期408-418,共11页
We use the sampling representations associated with Sturm-Liouville difference operators to derive generalized integral-valued trigonometric sums. This extends the known results where zeros of Chebyshev polynomials of... We use the sampling representations associated with Sturm-Liouville difference operators to derive generalized integral-valued trigonometric sums. This extends the known results where zeros of Chebyshev polynomials of the first kind are involved to the use of the eigenvalues of difference operators, which leads to new identities. In these identities Bernoulli's numbers play a role similar to that of Euler's in the old ones. Our technique differs from that of Byrne-Smith (1997) and Berndt-Yeap (2002). 展开更多
关键词 Trigonometric sums difference equations sampling theorem
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The Existence of Three Positive Solutions for p-Laplacian Difference Equation with Delay
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作者 WANG LIN-JUN GONG CHENG-CHUN 《Communications in Mathematical Research》 CSCD 2012年第4期337-348,共12页
In this paper, we study the multiplicity of positive solutions for a class of p-Laplacian difference equations with delay. We propose sufficient conditions for the existence of at least three positive solutions and we... In this paper, we study the multiplicity of positive solutions for a class of p-Laplacian difference equations with delay. We propose sufficient conditions for the existence of at least three positive solutions and we also provide two numerical examples to illustrate the theoretical results. 展开更多
关键词 P-LAPLACIAN difference equation DELAY fixed point theorem
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Discrete Arzelà-Ascoli Theorem on the Half Line and Its Application
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作者 LU YAN-QING MA RU-YUN 《Communications in Mathematical Research》 CSCD 2018年第3期221-229,共9页
The compactness criterion in l◇={x(·)∈l^∞(0,∞))|lim t→∞ x(t)=x(∞)} is given and as an application,we study the existence of positive solutions of second order boundary value problems of differenc... The compactness criterion in l◇={x(·)∈l^∞(0,∞))|lim t→∞ x(t)=x(∞)} is given and as an application,we study the existence of positive solutions of second order boundary value problems of difference equation on the half line by the fixedpoint theorem in cones. 展开更多
关键词 discrete Arzela-Ascoli theorem half line positive solution difference equation fixed point
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NEWTON'S THEOREM WITH RESPECT TO A LOT OFCENTERS AND THEIR APPLICATIONS
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作者 桂祖华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第7期659-663,共5页
In this paper we shall extend the paper [1] to a separate Taylor's Theorem with respect to a lot of centers, namely Newton's Theorem Of a lot of centers. From it we obtain the analogous results in the paper [2... In this paper we shall extend the paper [1] to a separate Taylor's Theorem with respect to a lot of centers, namely Newton's Theorem Of a lot of centers. From it we obtain the analogous results in the paper [2]. namely an interpolation formula of the difference of higher order. Finally we give their applications. 展开更多
关键词 Newton's interpolation formula Newton's polynomial of a lot of centers Newton's theorem of a lot of centers interpolation formula of the difference of higher order
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Positive periodic solutions of higher-dimensional nonlinear functional difference equations
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作者 DAI Bin-xiang ZOU Jie-zhong ZHANG Na 《Journal of Central South University of Technology》 2005年第z1期274-277,共4页
In this paper, we apply a cone theoretic fixed point theorem to obtain sufficient conditions for the existence of multiple positive periodic solutions to the higher-dimensional functional difference equations of the f... In this paper, we apply a cone theoretic fixed point theorem to obtain sufficient conditions for the existence of multiple positive periodic solutions to the higher-dimensional functional difference equations of the form:x(n+ 1) =A(n)x(n) +λh(n)f(x(n- τ(n))), n∈ Z. 展开更多
关键词 positive periodic solution difference EQUATIONS CONE fixed point theorem
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端接复杂电路传输线网络的电磁耦合时域并行计算方法 被引量:1
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作者 叶志红 张玉 鲁唱唱 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第2期713-719,共7页
针对端接复杂电路传输线(TL)网络的电磁耦合问题,仍缺乏高效的场路协同仿真技术。该文将传输线方程与时域有限差分(FDTD)方法、诺顿定理和置换定理以及NGSPICE软件相结合,并引入消息传递接口(MPI)并行技术,提出一种高效的时域混合并行算... 针对端接复杂电路传输线(TL)网络的电磁耦合问题,仍缺乏高效的场路协同仿真技术。该文将传输线方程与时域有限差分(FDTD)方法、诺顿定理和置换定理以及NGSPICE软件相结合,并引入消息传递接口(MPI)并行技术,提出一种高效的时域混合并行算法(FDTDTL-NGSPICE)。首先,根据诺顿定理和置换定理,将传输线网络分解为传输线子系统和复杂电路子系统,并构建对应的等效电路模型。然后,使用FDTDTL并行算法计算传输线子系统沿线各点的电压和电流,并获取对应诺顿等效电路的电流源和等效导纳大小。最后,使用NGSPICE对复杂电路子系统进行传导干扰分析,获得复杂电路各元件上的瞬态响应,并将端口电压反馈给传输线子系统作为边界,实现传输线网络电磁耦合的场线路联合协同仿真。通过对3类典型场景的计算实例,分别使用时域混合并行算法和电磁仿真软件CST电缆工作室(CS)进行数值模拟并对比,验证所提算法的置信度。 展开更多
关键词 传输线网络 复杂电路 诺顿定理 时域有限差分与传输线方程的混合并行算法 NGSPICE软件
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A Cauchy Problem for Some Fractional q-Difference Equations with Nonlocal Conditions
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作者 Maryam Al-Yami 《American Journal of Computational Mathematics》 2016年第2期159-165,共7页
In this paper, we discussed the problem of nonlocal value for nonlinear fractional q-difference equation. The classical tools of fixed point theorems such as Krasnoselskii’s theorem and Banach’s contraction principl... In this paper, we discussed the problem of nonlocal value for nonlinear fractional q-difference equation. The classical tools of fixed point theorems such as Krasnoselskii’s theorem and Banach’s contraction principle are used. At the end of the manuscript, we have an example that illustrates the key findings. 展开更多
关键词 Cauchy Problem Fractional q-difference Equation Nonlocal Conditions Fixed Point Krasnoselskii’s theorem
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一类分数阶q-差分方程广义反周期边值问题
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作者 孟鑫 国佳 《吉林大学学报(理学版)》 CAS 北大核心 2024年第2期237-242,共6页
考虑一类非线性Caputo型分数阶q-差分方程的广义反周期边值问题,用Banach不动点定理给出该广义反周期边值问题解的存在唯一性结果,并给出一个应用实例.
关键词 Caputo分数阶q-导数 分数阶q-差分方程 广义反周期边值问题 BANACH不动点定理
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R_(+)^(N)上不同阶椭圆方程组的Liouville型定理
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作者 赵围围 邵晓翎 +1 位作者 胡昌慧 程之羽 《应用数学》 北大核心 2024年第2期482-488,共7页
本文研究带Navier边值的不同阶椭圆方程组的Liouville型问题.主要结论的证明采用了伸缩变换,双边引理和积分形式的移动平面方法.
关键词 不同阶椭圆方程 LIOUVILLE型定理 Navier边值
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