期刊文献+
共找到104篇文章
< 1 2 6 >
每页显示 20 50 100
Double Elzaki Transform Decomposition Method for Solving Non-Linear Partial Differential Equations
1
作者 Moh A. Hassan Tarig M. Elzaki 《Journal of Applied Mathematics and Physics》 2020年第8期1463-1471,共9页
In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Trans... In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Transform and Adomian Decomposition Method. This technique is hereafter provided and supported with necessary illustrations, together with some attached examples. The results reveal that the new method is very efficient, simple and can be applied to other non-linear problems. 展开更多
关键词 Double Elzaki Transform Adomian Decomposition Method non-linear partial differential equations
下载PDF
Linear Quadratic Optimal Control for Systems Governed by First-Order Hyperbolic Partial Differential Equations
2
作者 XUE Xiaomin XU Juanjuan ZHANG Huanshui 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2024年第1期230-252,共23页
This paper focuses on linear-quadratic(LQ)optimal control for a class of systems governed by first-order hyperbolic partial differential equations(PDEs).Different from most of the previous works,an approach of discret... This paper focuses on linear-quadratic(LQ)optimal control for a class of systems governed by first-order hyperbolic partial differential equations(PDEs).Different from most of the previous works,an approach of discretization-then-continuousization is proposed in this paper to cope with the infinite-dimensional nature of PDE systems.The contributions of this paper consist of the following aspects:(1)The differential Riccati equations and the solvability condition of the LQ optimal control problems are obtained via the discretization-then-continuousization method.(2)A numerical calculation way of the differential Riccati equations and a practical design way of the optimal controller are proposed.Meanwhile,the relationship between the optimal costate and the optimal state is established by solving a set of forward and backward partial difference equations(FBPDEs).(3)The correctness of the method used in this paper is verified by a complementary continuous method and the comparative analysis with the existing operator results is presented.It is shown that the proposed results not only contain the classic results of the standard LQ control problem of systems governed by ordinary differential equations as a special case,but also support the existing operator results and give a more convenient form of computation. 展开更多
关键词 Discretization-then-continuousization method first-order hyperbolic partial differential equations forward and backward partial difference equations linear quadratic optimal control.
原文传递
The Jaffa Transform for Hessian Matrix Systems and the Laplace Equation
3
作者 Daniel A. Jaffa 《Journal of Applied Mathematics and Physics》 2024年第1期98-125,共28页
Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of ... Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of linear second-order partial differential equations. This paper discusses the Hessian and its applications in optimization, and then proceeds to introduce and derive the notion of the Jaffa Transform, a new linear operator that directly maps a Hessian square matrix space to the initial corresponding scalar field in nth dimensional Euclidean space. The Jaffa Transform is examined, including the properties of the operator, the transform of notable matrices, and the existence of an inverse Jaffa Transform, which is, by definition, the Hessian matrix operator. The Laplace equation is then noted and investigated, particularly, the relation of the Laplace equation to Poisson’s equation, and the theoretical applications and correlations of harmonic functions to Hessian matrices. The paper concludes by introducing and explicating the Jaffa Theorem, a principle that declares the existence of harmonic Jaffa Transforms, which are, essentially, Jaffa Transform solutions to the Laplace partial differential equation. 展开更多
关键词 Hessian Matrices Jacobian Matrices Laplace equation linear partial differential equations Systems of partial differential equations Harmonic Functions Incompressible and Irrotational Fluid Mechanics
下载PDF
ON THE HOLOMORPHIC SOLUTION OF NON-LINEAR TOTALLY CHARACTERISTIC EQUATIONS WITH SEVERAL SPACE VARIABLES 被引量:5
4
作者 陈化 罗壮初 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期393-403,共11页
In this paper the authors study a class of non-linear singular partial differential equation in complex domain Ct x Cxn. Under certain assumptions, they prove the existence and uniqueness of holomorphic solution near ... In this paper the authors study a class of non-linear singular partial differential equation in complex domain Ct x Cxn. Under certain assumptions, they prove the existence and uniqueness of holomorphic solution near origin of Ct x Cxn. 展开更多
关键词 non-linear SINGULAR partial differential equation HOLOMORPHIC SOLUTION
下载PDF
Interaction of Conormal Waves With Strong and Weak Singularities For Semi-Linear Equations
5
作者 Wang Weike Sheng Weiming(Department of Mathematics, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期20-24,共5页
InteractionofConormalWavesWithStrongandWeakSingularitiesforSemi-LinearEquations¥WangWeike;ShengWeiming(Depar... InteractionofConormalWavesWithStrongandWeakSingularitiesforSemi-LinearEquations¥WangWeike;ShengWeiming(DepartmentofMathematic... 展开更多
关键词 SEMI-linear HYPERBOLIC partial differential equation conormal distribution nonlinear wave energy ESTIMATE
下载PDF
SEMI-LINEAR SYSTEMS OF BACKWARD STOCHASTIC PARTIAL DIFFERENTIAL EQUATIONS IN R^n 被引量:2
6
作者 TANGSHANJIAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2005年第3期437-456,共20页
This paper explores the diffeomorphism of a backward stochastic ordinary differential equation (BSDE) to a system of semi-linear backward stochastic partial differential equations (BSPDEs), under the inverse of a stoc... This paper explores the diffeomorphism of a backward stochastic ordinary differential equation (BSDE) to a system of semi-linear backward stochastic partial differential equations (BSPDEs), under the inverse of a stochastic flow generated by an ordinary stochastic differential equation (SDE). The author develops a new approach to BSPDEs and also provides some new results. The adapted solution of BSPDEs in terms of those of SDEs and BSDEs is constructed. This brings a new insight on BSPDEs, and leads to a probabilistic approach. As a consequence, the existence, uniqueness, and regularity results are obtained for the (classical, Sobolev, and distributional) solution of BSPDEs.The dimension of the space variable x is allowed to be arbitrary n, and BSPDEs are allowed to be nonlinear in both unknown variables, which implies that the BSPDEs may be nonlinear in the gradient. Due to the limitation of space, however, this paper concerns only classical solution of BSPDEs under some more restricted assumptions. 展开更多
关键词 半线性系统 反馈随机偏微分方程 概率表达式 随机流动
原文传递
Mild Solutions of a Class of Conformable Fractional Differential Equations with Nonlocal Conditions 被引量:1
7
作者 Mohamed BOUAOUID 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2023年第2期249-261,共13页
This paper deals with the existence,uniqueness and continuous dependence of mild solutions for a class of conformable fractional differential equations with nonlocal initial conditions.The results are obtained by mean... This paper deals with the existence,uniqueness and continuous dependence of mild solutions for a class of conformable fractional differential equations with nonlocal initial conditions.The results are obtained by means of the classical fixed point theorems combined with the theory of cosine family of linear operators. 展开更多
关键词 fractional partial differential equations fractional derivatives and integrals cosine family of linear operators nonlocal conditions
原文传递
New Kamenev-type Oscillation Criteria for Half-linear Partial Differential Equations
8
作者 Ge-feng YANG Zhi-ting XU 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2012年第3期535-548,共14页
We establish new Kamenev-type oscillation criteria for the half-linear partial differential equation with damping under quite general conditions. These results are extensions of the recent results developed by Sun [Y.... We establish new Kamenev-type oscillation criteria for the half-linear partial differential equation with damping under quite general conditions. These results are extensions of the recent results developed by Sun [Y.G. Sun, New Kamenev-type oscillation criteria of second order nonlinear differential equations with damping, J. Math. Anal. Appl. 291 (2004) 341-351] for second order ordinary differential equations in a natural way, and improve some existing results in the literature. As applications, we illustrate our main results using two different types of half-linear partial differential equations. 展开更多
关键词 线性偏微分方程 振动准则 二阶非线性微分方程 二阶常微分方程 SUN 阻尼 数学
原文传递
Solving Inhomogeneous Linear Partial Differential Equations 被引量:1
9
作者 SCHWARZ Fritz 《Journal of Partial Differential Equations》 2010年第4期374-388,共15页
原文传递
An Alternative Method for Solving Lagrange's First-Order Partial Differential Equation with Linear Function Coefficients 被引量:1
10
作者 ISLAM Syed Md Himayetul DAS J. 《Journal of Partial Differential Equations》 CSCD 2015年第3期208-224,共17页
原文传递
On a Linear Partial Differential Equation of the Higher Order in Two Variables with Initial Condition Whose Coefficients are Real-valued Simple Step Functions
11
作者 PANTSULAIA Gogi GIORGADZE Givi 《Journal of Partial Differential Equations》 CSCD 2016年第1期1-13,共13页
原文传递
A Novel Nonlinear Algorithm for Typhoon Cloud Image Enhancement
12
作者 Chang-Jiang Zhang Bo Yang 《International Journal of Automation and computing》 EI 2011年第2期161-169,共9页
A novel nonlinear gray transform method is proposed to enhance the contrast of a typhoon cloud image.Generally,the typhoon cloud image obtained by a satellite cannot be directly used to make an accurate prediction of ... A novel nonlinear gray transform method is proposed to enhance the contrast of a typhoon cloud image.Generally,the typhoon cloud image obtained by a satellite cannot be directly used to make an accurate prediction of the typhoon s center or intensity because the contrast of the received typhoon cloud image may be bad.Our aim is to extrude the typhoon s eye in the typhoon cloud image.A normalized arc-tangent transformation operation is designed to enhance global contrast of the typhoon cloud image.Differential evolution algorithm is used to choose the optimal nonlinear transform parameter.Finally,geodesic activity contour model is used to extract the typhoon's eye to verify the performance of the proposed method.Experimental results show that the proposed method can efficiently enhance the global contrast of the typhoon cloud image while greatly extruding the typhoon's eye. 展开更多
关键词 强台风 图像增强算法 非线性 卫星云图 差分进化算法 活动轮廓模型 变换方法 全球对比
下载PDF
部分信息下时滞倒向重随机系统线性二次最优控制问题
13
作者 许洁 张瑞 《通化师范学院学报》 2023年第12期33-37,共5页
文章研究了一类含有时滞的部分信息下的倒向重随机系统线性二次最优控制问题,利用经典的凸变分技术和对偶方法讨论了当系统状态方程含有时滞变量时系统对应的最优控制的显示表达式,并利用经典的平行四边形法则证得最优控制的唯一性.
关键词 时滞倒向重随机微分方程 时滞 部分信息 线性系统 最优控制
下载PDF
ANTI-PERIODIC SOLUTIONS FOR FIRST AND SECOND ORDER NONLINEAR EVOLUTION EQUATIONS IN BANACH SPACES
14
作者 WEIWei XIANGXiaoling 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2004年第1期96-108,共13页
In this paper, a new existence theorem of anti-periodic solutions for a class ofstrongly nonlinear evolution equations in Banach spaces is presented. The equations contain nonlinear monotone operators and a nonmonoton... In this paper, a new existence theorem of anti-periodic solutions for a class ofstrongly nonlinear evolution equations in Banach spaces is presented. The equations contain nonlinear monotone operators and a nonmonotone perturbation. Moreover, throughan appropriate transformation, the existence of anti-periodic solutions for a class of secondorder nonlinear evolution equations is verified. Our abstract results are illustrated by anexample from quasi-linear partial differential equations with time anti-periodic conditionsand an example from quasi-linear anti-periodic hyperbolic differential equations. 展开更多
关键词 反周期解 非线性发展方程 存在性 非单调扰动 BANACH空间 拟线性偏微分方程 单调算子
原文传递
动边界上Burgers方程的非线性边值一初值问题 被引量:10
15
作者 王跃明 张小勇 +1 位作者 尤国伟 王明亮 《河南科技大学学报(自然科学版)》 CAS 2003年第4期98-100,共3页
借助应用齐次平衡原则导出的B¨acklund变换和Cole-Hopf变换将动边界上给定流量型条件的Burgers方程的非线性边值—初值问题化为线性方程的边值—初值问题。当动边界是时间t的线性函数时,得出了问题的精确解析解。
关键词 BURGERS方程 非线性边值-初值问题 齐次平衡原则 BACKLUND变换 Cole-Hopf变换 非线性偏微分方程
下载PDF
单相有源电力滤波器非线性统一控制策略 被引量:10
16
作者 乐江源 谢运祥 +1 位作者 公伟勇 张志 《控制理论与应用》 EI CAS CSCD 北大核心 2011年第5期652-658,共7页
目前有源电力滤波器控制策略都采用电流内环和电压外环的双环控制.本文提出了一种基于精确反馈线性化的单相有源电力滤波器统一控制策略.在单相有源电力滤波器仿射非线性模型基础上,通过求解偏微分方程得到一个包含补偿电流变量和直流... 目前有源电力滤波器控制策略都采用电流内环和电压外环的双环控制.本文提出了一种基于精确反馈线性化的单相有源电力滤波器统一控制策略.在单相有源电力滤波器仿射非线性模型基础上,通过求解偏微分方程得到一个包含补偿电流变量和直流侧电压变量的输出函数,并推导出了其状态反馈精确线性化非线性控制律,将原非线性系统转换成微分同胚的二阶线性系统.选取适当的反馈系数设计控制器使输出函数渐近跟踪指令参考值,从而实现了电流和电压的统一控制.最后通过仿真分析和实验验证了所提方案的优越性和可行性. 展开更多
关键词 有源电力滤波器 统一控制 精确反馈线性化 偏微分方程 微分同胚
下载PDF
基于PDE的图像去噪和反差增强同步算法 被引量:13
17
作者 陈颖 彭进业 +2 位作者 王大凯 吴亚鹏 王宾 《计算机工程》 CAS CSCD 北大核心 2009年第23期224-226,共3页
针对反差较低且包含噪声污染的灰度图像,设计分段线性拉伸函数,引入TV下降流,建立新的偏微分方程(PDE)数学模型。该模型通过设置参数λ灵活控制去噪和反差增强的程度,实现2种灰度图像处理手段的同步进行。对比实验表明,该方法可有效缓... 针对反差较低且包含噪声污染的灰度图像,设计分段线性拉伸函数,引入TV下降流,建立新的偏微分方程(PDE)数学模型。该模型通过设置参数λ灵活控制去噪和反差增强的程度,实现2种灰度图像处理手段的同步进行。对比实验表明,该方法可有效缓解传统处理方法存在的问题,在抑制噪声的同时增强图像的反差。 展开更多
关键词 偏微分方程 图像去噪 反差增强 整体变分 分段线性拉伸函数
下载PDF
齐次平衡法与Burgers-KdV方程的精确解 被引量:5
18
作者 刘春平 蔡蕃 《扬州大学学报(自然科学版)》 CAS CSCD 1998年第4期11-13,共3页
对齐次平衡法进行适当修改。
关键词 偏微分方程 齐次平衡法 B-KdV方程 精确解
下载PDF
双重介质分形油藏非线性流动分析 被引量:8
19
作者 同登科 刘敏鸽 《石油大学学报(自然科学版)》 CSCD 北大核心 2003年第2期59-62,共4页
在非线性偏微分方程中 ,根据弱可压缩液体的假设 ,忽略了二次梯度项 ,这在混气石油和低渗透储层的计算中将产生误差。对于双重分形介质流动系统及其物质平衡方程 ,在保留非线性偏微分方程中所有项的前提下建立了新的双孔模型。采用Dougl... 在非线性偏微分方程中 ,根据弱可压缩液体的假设 ,忽略了二次梯度项 ,这在混气石油和低渗透储层的计算中将产生误差。对于双重分形介质流动系统及其物质平衡方程 ,在保留非线性偏微分方程中所有项的前提下建立了新的双孔模型。采用Douglas Jones方法 ,获得了定产生产和定压生产时分形介质双孔模型的数值解。结果表明 ,对于定产生产 ,油藏参数cLD对非线性影响更敏感 ,线性解和非线性解的偏差约为 10 %。对于定压生产 ,cLD的影响可忽略不计。讨论了液体压缩系数和双重分形介质参数变化时的压力变化规律 ,给出了典型压力曲线。 展开更多
关键词 双重介质分形油藏 非线性流动分析 分形介质 双孔模型 非线性偏微分方程 数值解 动态分折
下载PDF
精确反馈线性化中虚拟输出函数的求解与应用 被引量:2
20
作者 王新屏 张显库 毕宁宁 《应用基础与工程科学学报》 EI CSCD 2010年第2期321-329,共9页
为使精确反馈线性化方法得到更广泛的应用,给出虚拟输出函数的简便求解方法.首先将虚拟输出函数的求解转化为偏微分方程组的求解,然后针对这类偏微分方程组的特点提出仿照求解齐次线性方程组的方法可以简便的求出虚拟输出函数.利用该方... 为使精确反馈线性化方法得到更广泛的应用,给出虚拟输出函数的简便求解方法.首先将虚拟输出函数的求解转化为偏微分方程组的求解,然后针对这类偏微分方程组的特点提出仿照求解齐次线性方程组的方法可以简便的求出虚拟输出函数.利用该方法为非线性舵鳍联合系统实现了状态反馈线性化,并基于闭环增益成形算法设计了非线性鲁棒控制器,仿真表明该控制器对原非线性系统能起到良好的控制作用.该方法简单、实用,对于状态反馈线性化的实现具有一定的指导意义. 展开更多
关键词 精确反馈线性化 虚拟输出函数 偏微分方程组 舵鳍联合 闭环增益成形 非线性 鲁棒
下载PDF
上一页 1 2 6 下一页 到第
使用帮助 返回顶部