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INSTABILITY OF SOLUTION FOR THE FOURTH ORDER LINEAR DIFFERENTIAL EQUATION WITH VARIED COEFFICIENT
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作者 卢德渊 廖宗璜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第5期481-497,共17页
In this paper, we give some sufficient conditions of the instability for the fourth order linear differential equation with varied coefficient, at least one of the characteristic roots of which has positive real part,... In this paper, we give some sufficient conditions of the instability for the fourth order linear differential equation with varied coefficient, at least one of the characteristic roots of which has positive real part, by means of Liapunov's second method. 展开更多
关键词 ordinary differential equation motive stability theory linear differential equation with varied coefficient
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Equation governing the probability density evolution of multi-dimensional linear fractional differential systems subject to Gaussian white noise
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作者 Yi Luo Meng-Ze Lyu +1 位作者 Jian-Bing Chen Pol D.Spanos 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第3期199-208,共10页
Stochastic fractional differential systems are important and useful in the mathematics,physics,and engineering fields.However,the determination of their probabilistic responses is difficult due to their non-Markovian ... Stochastic fractional differential systems are important and useful in the mathematics,physics,and engineering fields.However,the determination of their probabilistic responses is difficult due to their non-Markovian property.The recently developed globally-evolving-based generalized density evolution equation(GE-GDEE),which is a unified partial differential equation(PDE)governing the transient probability density function(PDF)of a generic path-continuous process,including non-Markovian ones,provides a feasible tool to solve this problem.In the paper,the GE-GDEE for multi-dimensional linear fractional differential systems subject to Gaussian white noise is established.In particular,it is proved that in the GE-GDEE corresponding to the state-quantities of interest,the intrinsic drift coefficient is a time-varying linear function,and can be analytically determined.In this sense,an alternative low-dimensional equivalent linear integer-order differential system with exact closed-form coefficients for the original highdimensional linear fractional differential system can be constructed such that their transient PDFs are identical.Specifically,for a multi-dimensional linear fractional differential system,if only one or two quantities are of interest,GE-GDEE is only in one or two dimensions,and the surrogate system would be a one-or two-dimensional linear integer-order system.Several examples are studied to assess the merit of the proposed method.Though presently the closed-form intrinsic drift coefficient is only available for linear stochastic fractional differential systems,the findings in the present paper provide a remarkable demonstration on the existence and eligibility of GE-GDEE for the case that the original high-dimensional system itself is non-Markovian,and provide insights for the physical-mechanism-informed determination of intrinsic drift and diffusion coefficients of GE-GDEE of more generic complex nonlinear systems. 展开更多
关键词 Globally-evolving-based generalized density evolution equation(GE-GDEE) linear fractional differential system Non-Markovian system Analytical intrinsic drift coefficient Dimension reduction
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EXISTENCE OF MEROMORPHIC SOLUTIONS OF SOME HIGHER ORDER LINEAR DIFFERENTIAL EQUATIONS
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作者 张晓梅 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期600-608,共9页
This article discusses the problems on the existence of meromorphic solutions of some higher order linear differential equations with meromorphic coefficients. Some nice results are obtained. And these results perfect... This article discusses the problems on the existence of meromorphic solutions of some higher order linear differential equations with meromorphic coefficients. Some nice results are obtained. And these results perfect the complex oscillation theory of meromorphic solutions of linear differential equations. 展开更多
关键词 Higher order linear differential equation meromorphic coefficient meromorphicsolutions the first coefficient
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ON THE DEPENDENT PROPERTY OF SOLUTIONS FOR HIGHER ORDER PERIODIC DIFFERENTIAL EQUATIONS 被引量:4
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作者 陈宗煊 高仕安 孙光镐 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期743-752,共10页
This article investigates the property of linearly dependence of solutions f(z) and f(z + 2πi) for higher order linear differential equations with entire periodic coefficients.
关键词 differential equation linear dependent entire periodic coefficient
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CONVERGENCE OF AN IMMERSED INTERFACE UPWIND SCHEME FOR LINEAR ADVECTION EQUATIONS WITH PIECEWISE CONSTANT COEFFICIENTS I:L^1-ERROR ESTIMATES 被引量:7
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作者 Xin Wen Shi Jin 《Journal of Computational Mathematics》 SCIE EI CSCD 2008年第1期1-22,共22页
We study the L^l-error estimates for the upwind scheme to the linear advection equations with a piecewise constant coefficients modeling linear waves crossing interfaces. Here the interface condition is immersed into ... We study the L^l-error estimates for the upwind scheme to the linear advection equations with a piecewise constant coefficients modeling linear waves crossing interfaces. Here the interface condition is immersed into the upwind scheme. We prove that, for initial data with a bounded variation, the numerical solution of the immersed interface upwind scheme converges in L^l-norm to the differential equation with the corresponding interface condition. We derive the one-halfth order L^l-error bounds with explicit coefficients following a technique used in [25]. We also use some inequalities on binomial coefficients proved in a consecutive paper [32]. 展开更多
关键词 linear advection equations Immersed interface upwind scheme Piecewise constant coefficients Error estimate Half order error bound
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CONVERGENCE OF AN IMMERSED INTERFACE UPWIND SCHEME FOR LINEAR ADVECTION EQUATIONS WITH PIECEWISE CONSTANT COEFFICIENTS Ⅱ: SOME RELATED BINOMIAL COEFFICIENT INEQUALITIES 被引量:2
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作者 Xin Wen 《Journal of Computational Mathematics》 SCIE CSCD 2009年第4期474-483,共10页
In this paper we give proof of three binomial coefficient inequalities. These inequalities are key ingredients in [Wen and Jin, J. Comput. Math. 26, (2008), 1-22] to establish the L^1-error estimates for the upwind ... In this paper we give proof of three binomial coefficient inequalities. These inequalities are key ingredients in [Wen and Jin, J. Comput. Math. 26, (2008), 1-22] to establish the L^1-error estimates for the upwind difference scheme to the linear advection equations with a piecewise constant wave speed and a general interface condition, which were further used to establish the L^1-error estimates for a Hamiltonian-preserving scheme developed in [Jin and Wen, Commun. Math. Sci. 3, (2005), 285-315] to the Liouville equation with piecewise constant potentials [Wen and Jin, SIAM J. Numer. Anal. 46, (2008), 2688-2714]. 展开更多
关键词 Binomial coefficient linear advection equations Immersed interface upwindscheme Piecewise constant coefficients Error estimates.
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LINEARIZED OSCILLATIONS FOR ODD-ORDERNEUTRAL DELAY DIFFERENTIAL EQUATIONSWITH ASYMPTOTIC PERIODIC COEFFICIENTS
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作者 李雪梅 申建华 《Annals of Differential Equations》 1999年第3期289-297,共9页
In this paper, we prove that, under appropriate hypotheses, the odd-order nonlinear neutral delay differential equation has the same oscillatory character as the associated linear equation with periodic coefficients O... In this paper, we prove that, under appropriate hypotheses, the odd-order nonlinear neutral delay differential equation has the same oscillatory character as the associated linear equation with periodic coefficients Our method is based on the establishment of a new comparison theorem for the oscillation of Eq.(E). Hence we prove that the parameter set such that Eq.(E) has a nonoscillatory solution is closed in certain metric space, and avoid the difficulty to set the necessary and sufficient condition for the oscillation of Eq.(E). 展开更多
关键词 asymptotic periodic coefficients neutral delay differential equation linearized oscillstion comparison theorem
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High Accuracy Arithmetic Average Discretization for Non-Linear Two Point Boundary Value Problems with a Source Function in Integral Form
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作者 Ranjan K. Mohanty Deepika Dhall 《Applied Mathematics》 2011年第10期1243-1251,共9页
In this article, we report the derivation of high accuracy finite difference method based on arithmetic average discretization for the solution of Un=F(x,u,u′)+∫K(x,s)ds , 0 x s < 1 subject to natural boundary co... In this article, we report the derivation of high accuracy finite difference method based on arithmetic average discretization for the solution of Un=F(x,u,u′)+∫K(x,s)ds , 0 x s < 1 subject to natural boundary conditions on a non-uniform mesh. The proposed variable mesh approximation is directly applicable to the integro-differential equation with singular coefficients. We need not require any special discretization to obtain the solution near the singular point. The convergence analysis of a difference scheme for the diffusion convection equation is briefly discussed. The presented variable mesh strategy is applicable when the internal grid points of the solution space are both even and odd in number as compared to the method discussed by authors in their previous work in which the internal grid points are strictly odd in number. The advantage of using this new variable mesh strategy is highlighted computationally. 展开更多
关键词 Variable Mesh ARITHMETIC Average DISCRETIZATION NON-linear Integro-differential equation Diffusion equation Simpson’s 1/3 Rd Rule SINGULAR coefficients Burgers’ equation Maximum Absolute Errors
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一类带有分段常数变元的线性时滞微分方程的振动判据
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作者 张冰清 寇春海 《东华大学学报(自然科学版)》 CAS 北大核心 2024年第2期170-180,共11页
针对一类带有分段变元的线性时滞微分方程,在系数缓慢变化的情形下,利用Bolzano-Weierstrass定理,建立判定其振动性的充分条件,将已有的下极限型条件改进为上极限型条件,进而可以判定部分原先所不能判定的方程的振动性,并采用2个例子证... 针对一类带有分段变元的线性时滞微分方程,在系数缓慢变化的情形下,利用Bolzano-Weierstrass定理,建立判定其振动性的充分条件,将已有的下极限型条件改进为上极限型条件,进而可以判定部分原先所不能判定的方程的振动性,并采用2个例子证明其有效性。 展开更多
关键词 线性时滞微分方程 分段常数变元 振动
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Linear quadratic optimal control of conditional McKean-Vlasov equation with random coefficients and applications 被引量:1
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作者 Huyen Pham 《Probability, Uncertainty and Quantitative Risk》 2016年第1期252-277,共26页
We consider the optimal control problem for a linear conditional McKeanVlasov equation with quadratic cost functional.The coefficients of the system and the weighting matrices in the cost functional are allowed to be ... We consider the optimal control problem for a linear conditional McKeanVlasov equation with quadratic cost functional.The coefficients of the system and the weighting matrices in the cost functional are allowed to be adapted processes with respect to the common noise filtration.Semi closed-loop strategies are introduced,and following the dynamic programming approach in(Pham and Wei,Dynamic programming for optimal control of stochastic McKean-Vlasov dynamics,2016),we solve the problem and characterize time-consistent optimal control by means of a system of decoupled backward stochastic Riccati differential equations.We present several financial applications with explicit solutions,and revisit,in particular,optimal tracking problems with price impact,and the conditional mean-variance portfolio selection in an incomplete market model. 展开更多
关键词 Stochastic McKean-Vlasov SDEs Random coefficients linear quadratic optimal control Dynamic programming Riccati equation Backward stochastic differential equation
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韦达定理在推导常系数齐次线性微分方程通解式中的应用
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作者 吴方舟 《辽宁师专学报(自然科学版)》 2024年第2期4-6,19,共4页
在探讨常系数齐次线性微分方程的通解时,通常侧重于通过求解代数方程即特征方程来找到方程的根,进而构建出通解.提出一种利用韦达定理来直接推导出这种微分方程通解形式的方法.通过利用韦达定理建立方程的系数与其根之间的直接联系,从... 在探讨常系数齐次线性微分方程的通解时,通常侧重于通过求解代数方程即特征方程来找到方程的根,进而构建出通解.提出一种利用韦达定理来直接推导出这种微分方程通解形式的方法.通过利用韦达定理建立方程的系数与其根之间的直接联系,从而更为直观地构造出微分方程的通解.该方法为求解此类问题提供了一种新的思路. 展开更多
关键词 韦达定理 常系数齐次线性微分方程 通解
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用于电磁暂态计算的一种高精度快速积分算法
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作者 裴正廷 《电工技术》 2024年第18期23-28,共6页
为提高电力系统中电磁暂态的计算效率,提出一种高精度大步长积分的LSD算法。首先描述电力系统电磁暂态现象的状态空间表达式通过矩阵运算变换成一阶常系数微分方程组,然后利用LSD积分算法对其进行数值求解,最后将该算法用于输电线路和... 为提高电力系统中电磁暂态的计算效率,提出一种高精度大步长积分的LSD算法。首先描述电力系统电磁暂态现象的状态空间表达式通过矩阵运算变换成一阶常系数微分方程组,然后利用LSD积分算法对其进行数值求解,最后将该算法用于输电线路和大型电力变压器绕组的电磁暂态计算,结果表明该算法的稳定性与仿真时间步长无关,可利用大步长进行数值运算以提高计算效率。与小步长计算的CDA算法相比,该算法在保持精度的基础上,在一定程度上可抑制数值振荡。 展开更多
关键词 电磁暂态 LSD算法 常系数微分方程组 CDA算法
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变系数Burgers方程的一些新精确解 被引量:26
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作者 张金良 李向正 +2 位作者 王明亮 王跃明 方宗德 《河南科技大学学报(自然科学版)》 CAS 2003年第1期108-110,共3页
利用齐次平衡原则 ,导出了变系数Burgers方程的B¨acklund变换 (BT) ;并由该B¨acklund变换 。
关键词 变系数BURGERS方程 精确解 齐次平衡 BACKLUND变换 非线性数学物理方程
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磁浮列车的动力稳定性分析与Liapunov指数 被引量:17
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作者 周又和 武建军 +1 位作者 郑晓静 何丽红 《力学学报》 EI CSCD 北大核心 2000年第1期42-51,共10页
针对弹性轨道上的磁悬浮列车线性动力控制系统,给出了采用Liapunov特性指数判别动力系统稳定性的判据:当动力系统的全部Liapunov特性指数小于零时,动力控制系统是稳定的;而当动力系统中有一Liapunov特性指... 针对弹性轨道上的磁悬浮列车线性动力控制系统,给出了采用Liapunov特性指数判别动力系统稳定性的判据:当动力系统的全部Liapunov特性指数小于零时,动力控制系统是稳定的;而当动力系统中有一Liapunov特性指数大于零时,动力系统就成为不稳定的.由于Liapunov特性指数可以由数值积分方式方便地给出,这一判断方法对于不便搜索参数稳定区域的高维动力系统,与寻求周期变系数线性常微分方程动力系统的Floquet理论的变换矩阵特征值相比,具有计算量小和搜索方法简单等优点.数值算例表明本文方法是有效的. 展开更多
关键词 磁悬浮列车 Liapunov特性指数 动力稳定性
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一类非线性热传导方程的线性化解法 被引量:5
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作者 许丽萍 张春阳 米小红 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2008年第4期393-396,共4页
提出了用一阶线性常微分方程及其解构造非线性偏微分方程精确解的线性化解法.利用该方法求出(3+1)维和(1+1)维的Kolmogorov-Petrovskii-Piskunov型方程的精确解,其中包括扭状孤立波和代数孤立波解,并把(1+1)维的Kolmogorov-Petrovskii-P... 提出了用一阶线性常微分方程及其解构造非线性偏微分方程精确解的线性化解法.利用该方法求出(3+1)维和(1+1)维的Kolmogorov-Petrovskii-Piskunov型方程的精确解,其中包括扭状孤立波和代数孤立波解,并把(1+1)维的Kolmogorov-Petrovskii-Piskunov型方程推广到具有任意次非线性项的一般热传导方程,得到了其解. 展开更多
关键词 非线性热传导方程 线性常微分方程 线性化解法 精确解
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一种二阶变系数线性微分方程的求解方法 被引量:11
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作者 胡劲松 李先富 郑克龙 《重庆工商大学学报(自然科学版)》 2005年第3期220-222,共3页
在知道二阶变系数线性齐次微分方程一个特解的情况下,通过常数变易法,将二阶变系数线性非齐次微分方程转化为一阶线性微分方程,从而给出运算量较小的二阶变系数线性非齐次微分方程通解的一般公式,也给出了用刘维尔定理求解二阶变系数线... 在知道二阶变系数线性齐次微分方程一个特解的情况下,通过常数变易法,将二阶变系数线性非齐次微分方程转化为一阶线性微分方程,从而给出运算量较小的二阶变系数线性非齐次微分方程通解的一般公式,也给出了用刘维尔定理求解二阶变系数线性齐次微分方程的一个理论依据. 展开更多
关键词 二阶变系数线性微分方程 求解方法 非齐次微分方程 一阶线性微分方程 常数变易法 刘维尔定理 运算量 特解 通解
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一类二阶常微分方程组的特解公式 被引量:9
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作者 吴幼明 孔碧洁 何小媚 《佛山科学技术学院学报(自然科学版)》 CAS 2006年第4期7-11,共5页
采用待定系数法,给出了非齐次项为三角函数与指数函数乘积的三维二阶常系数线性微分方程组的特解公式,并通过算例验证了微分方程组的特解公式的正确性。
关键词 常系数 微分方程组 通解公式 待定系数法 特解
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二阶常系数线性微分方程特解的微分算子法 被引量:6
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作者 李绍刚 徐安农 《桂林电子科技大学学报》 2008年第4期330-333,共4页
微分算子法是求解常系数非齐次线性微分方程特解的有效方法,基于算子多项式的理论,针对二阶常系数线性微分方程,论文给出了非线性项为指数函数、三角函数、幂函数及其混合函数的微分算子特解公式,实例表明特解公式在解题中具有可应用性... 微分算子法是求解常系数非齐次线性微分方程特解的有效方法,基于算子多项式的理论,针对二阶常系数线性微分方程,论文给出了非线性项为指数函数、三角函数、幂函数及其混合函数的微分算子特解公式,实例表明特解公式在解题中具有可应用性、有效性和简捷性。 展开更多
关键词 线性微分方程 常系数 微分算子 特解
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一类二阶常微分方程组的通解 被引量:8
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作者 吴幼明 卢永全 杜焕芬 《佛山科学技术学院学报(自然科学版)》 CAS 2009年第5期18-22,共5页
采用降阶和特征根(欧拉)方法,给出了一类三维二阶常系数微分方程组的通解公式,并通过算例与拉氏变换法进行了比较,说明了利用通解公式求解高阶微分方程组比采用其他方法求解更简捷。
关键词 常系数 微分方程组 通解公式 特解
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四阶线性微分方程的算子解法 被引量:7
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作者 孙法国 任丽娜 《西安工程大学学报》 CAS 2009年第6期142-146,共5页
通过算子代换引入特征方程的概念,将微分方程化为代数方程,得到了四阶线性微分方程可降阶的充要条件,并给出了求解对应方程通解的方法.
关键词 变系数 线性微分方程 算子解法 特征方程
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