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THE ESTIMATION OF CHARACTERISTIC EXPONENTS FOR A CLASS OF SECOND ORDER LINEAR DIFFERENTIAL EQUATION WITH PERIODIC COEFFICIENTS
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作者 Wu Chengqiang 《Annals of Differential Equations》 2006年第4期582-588,共7页
In this paper we shall give a simple and easy method to estimate the characteristic exponents for a class of second order linear different equation with periodic coefficient which frequently occurs in application.
关键词 second order linear equation characteristic exponent ESTIMATION
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Two parametric approaches for eigenstructure assignment in second-order linear systems 被引量:4
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作者 Guangren DUAN(Center for Control Theory and Guidance Technology, Harbin Institute of Technology, P.O. Box 416, Harbin Heilongjiang 150001, China) 《控制理论与应用(英文版)》 EI 2003年第1期59-64,共6页
This paper considers eigenstructure assignment in second-order linear systems via proportional plus derivative feedback. It is shown that the problem is closely related to a type of so-called second-order Sylvester ma... This paper considers eigenstructure assignment in second-order linear systems via proportional plus derivative feedback. It is shown that the problem is closely related to a type of so-called second-order Sylvester matrix equations. Through establishing two general parametric solutions to this type of matrix equations, two complete parametric methods for the proposed eigenstructure assignment problem are presented. Both methods give simple complete parametric expressions for the feedback gains and the closed-loop eigenvector matrices. The first one mainly depends on a series of singular value decompositions, and is thus numerically simple and reliable; the second one utilizes the right factorization of the system, and allows the closed-loop eigenvalues to be set undetermined and sought via certain optimization procedures. An example shows the effectiveness of the proposed approaches. Keywords Second-order linear systems - Eigenstructure assignment - Proportional plus derivative feedback - Parametric solution - Singular value decompoition - Right factorization This work was supported in part by the Chinese Outstanding Youth Foundation (No.69504002). 展开更多
关键词 second-order linear systems Eigenstructure assignment Proportional plus derivative feedback Parametric solution Singular value decompoition Right factorization
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Eigenstructure Assignment in a Class of Second-order Descriptor Linear Systems: A Complete Parametric Approach 被引量:4
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作者 Guang-Ren Duan Center for Control Theory and Guidance Technology, Harbin Institute of Technology, P. O. Box 416, Harbin, 150001, PRC Guo-Sheng Wang Department of Control Engineering, Academy of Armored Force Engineering, Beijing, 100072, PRC 《International Journal of Automation and computing》 EI 2005年第1期1-5,共5页
In this paper eigenstructure assignment via proportional-plus-derivative feedback is investigated for a class of second-order descriptor linear systems. Under certain conditions, simple, general and complete parametri... In this paper eigenstructure assignment via proportional-plus-derivative feedback is investigated for a class of second-order descriptor linear systems. Under certain conditions, simple, general and complete parametric solutions of both finite closed-loop eigenvector matrices and feedback gain matrices are derived. The parametric approach utilizes directly original system data, involves manipulations only on n-dimensional matrices, and reveals all the design degrees of freedom which can be further utilized to achieve certain additional system specifications. A numerical example shows the effect of the proposed approach. 展开更多
关键词 second order descriptor linear systems eigenstructure assignment proportional plus derivative feedback R CONTROLLABLE
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Design of Luenberger function observer with disturbance decoupling for matrix second-order linear systems-a parametric approach 被引量:1
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作者 Wu Yunli Duan Guangren 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期156-162,共7页
A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure ass... A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure assignment. By introducing the H2 norm of the transfer function from disturbance to estimation error, sufficient and necessary conditions for disturbance decoupling in matrix second-order linear systems are established and are arranged into constraints on the design parameters via Luenberger function observers in terms of the closed-loop eigenvalues and the group of design parameters provided by the eigenstructure assignment approach. Therefore, the disturbance decoupling problem is converted into an eigenstructure assignment problem with extra parameter constraints. A simple example is investigated to show the effect and simplicity of the approach. 展开更多
关键词 matrix second-order linear systems Luenberger function observers eigenstructure assignment disturbance decoupling
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ON GLOBAL MEROMORPHIC SOLUTIONS OF SECOND-ORDER LINEAR DIFFERENTIAL EQUATIONS WITH MEROMORPHIC COEFFICIENTS 被引量:1
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作者 孔荫莹 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期423-429,共7页
The main purpose of this article is to study the existence theories of global meromorphic solutions for some second-order linear differential equations with meromorphic coefficients, which perfect the solution theory ... The main purpose of this article is to study the existence theories of global meromorphic solutions for some second-order linear differential equations with meromorphic coefficients, which perfect the solution theory of such equations. 展开更多
关键词 second-order linear differential equations global meromorphic solutions mero-morphic continuation
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Parametric Approach for the Normal Luenberger Function Observer Design in Second-order Descriptor Linear Systems 被引量:2
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作者 Bin Zhou Guang-Ren Duan Yun-Li Wu 《International Journal of Automation and computing》 EI 2008年第2期125-131,共7页
In this paper, the normal Luenberger function observer design for second-order descriptor linear systems is considered. It is shown that the main procedure of the design is to solve a so-called second-order generalize... In this paper, the normal Luenberger function observer design for second-order descriptor linear systems is considered. It is shown that the main procedure of the design is to solve a so-called second-order generalized Sylvester-observer matrix equation. Based on an explicit parametric solution to this equation, a parametric solution to the normal Luenberger function observer design problem is given. The design degrees of freedom presented by explicit parameters can be further utilized to achieve some additional design requirements. 展开更多
关键词 second-order descriptor linear systems normal Luenberger functions observer Sylvester matrix equation parametricsolutions
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Observer design for matrix second-order linear systems: a parametric approach
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作者 WUYunli DUANGuangren 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2004年第3期449-453,共5页
The issue of designing a type of generalized Luenberger observers for matrix second-order linear (MSOL) systems was addressed in the matrix second-order framework. By introducing the concept of stable matrix pair for ... The issue of designing a type of generalized Luenberger observers for matrix second-order linear (MSOL) systems was addressed in the matrix second-order framework. By introducing the concept of stable matrix pair for MSOL systems, sufficient and necessary conditions for the design of the type of generalized Luenberger observers were given under the assumption of controllability and observability of the MSOL system. Based on the proposed conditions and the right coprime factorization of the system, a parametric approach to the design of such type of observers was presented. The proposed approach provides all the degrees of design freedom, which can be further utilized to achieve additional system specifications. A spring-mass system was utilized to show the effect of the proposed method. 展开更多
关键词 generalized luenberger OBSERVER MATRIX second-order linear systems DEGREES of design FREEDOM stable MATRIX PAIRS
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Unified parametric approaches for high-order integral observer design for matrix second-order linear systems
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作者 Guangren DUAN Yunli WU 《控制理论与应用(英文版)》 EI 2006年第2期133-139,共7页
A type of high-order integral observers for matrix second-order linear systems is proposed on the basis of generalized eigenstructure assignment via unified parametric approaches. Through establishing two general para... A type of high-order integral observers for matrix second-order linear systems is proposed on the basis of generalized eigenstructure assignment via unified parametric approaches. Through establishing two general parametric solutions to this type of generalized matrix second-order Sylvester matrix equations, two unified complete parametric methods for the proposed observer design problem are presented. Both methods give simple complete parametric expressions for the observer gain matrices. The first one mainly depends on a series of singular value decompositions, and is thus numerically simple and reliable; the second one utilizes the fight factorization of the system, and allows eigenvalues of the error system to be set undetermined and sought via certain optimization procedures. A spring-mass-dashpot system is utilized to illustrate the design procedure and show the effect of the proposed approach. 展开更多
关键词 Matrix second-order linear systems High-order integral observer Generalized eigenstructure assignment Singular value decomposition Right factorization
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Feasibility and Structural Feature on Monotone Second-Order Cone Linear Complementarity Problems in Hilbert Space
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作者 苗新河 郭胜娟 《Transactions of Tianjin University》 EI CAS 2015年第4期377-382,共6页
Given a real finite-dimensional or infinite-dimensional Hilbert space H with a Jordan product, the second-order cone linear complementarity problem(SOCLCP)is considered. Some conditions are investigated, for which the... Given a real finite-dimensional or infinite-dimensional Hilbert space H with a Jordan product, the second-order cone linear complementarity problem(SOCLCP)is considered. Some conditions are investigated, for which the SOCLCP is feasible and solvable for any element q?H. The solution set of a monotone SOCLCP is also characterized. It is shown that the second-order cone and Jordan product are interconnected. 展开更多
关键词 second-order CONE linear complementarity JORDAN frame JORDAN product Lorentz CONE ADJOINT operator
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Oscillation Criteria of second Order Non-Linear Differential Equations
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作者 Hishyar Kh. Abdullah 《Open Journal of Applied Sciences》 2012年第4期120-122,共3页
In this paper we are concerned with the oscillation criteria of second order non-linear homogeneous differential equation. Example have been given to illustrate the results.
关键词 component OSCILLATORY second order DIFFERENTIAL EQUATIONS Non-linear.
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Criteria for System of Three Second-Order Ordinary Differential Equations to Be Reduced to a Linear System via Restricted Class of Point Transformation
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作者 Supaporn Suksern Nawee Sakdadech 《Applied Mathematics》 2014年第3期553-571,共19页
This paper is devoted to the study of the linearization problem of system of three second-order ordinary differential equations and . The necessary conditions for linearization by general point transformation and are ... This paper is devoted to the study of the linearization problem of system of three second-order ordinary differential equations and . The necessary conditions for linearization by general point transformation and are found. The sufficient conditions for linearization by restricted class of point transformation and are obtained. Moreover, the procedure for obtaining the linearizing transformation is provided in explicit forms. Examples demonstrating the procedure of using the linearization theorems are presented. 展开更多
关键词 linearIZATION Problem Point Transformation SYSTEM of THREE second-order Ordinary Differential Equation
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A Semi-Analytical Method for Solutions of a Certain Class of Second Order Ordinary Differential Equations
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作者 S. O. Edeki H. I. Okagbue +1 位作者 A. A. Opanuga S. A. Adeosun 《Applied Mathematics》 2014年第13期2034-2041,共8页
This paper presents the theory and applications of a new computational technique referred to as Differential Transform Method (DTM) for solving second order linear ordinary differential equations, for both homogeneous... This paper presents the theory and applications of a new computational technique referred to as Differential Transform Method (DTM) for solving second order linear ordinary differential equations, for both homogeneous and nonhomogeneous cases. For the robustness and efficiency of the method, four examples are considered. The results indicate that the DTM is reliable and accurate when compared to the exact solutions of the solved problems. 展开更多
关键词 Differential TRANSFORM Method second order ODES linear Systems Series Solution
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基于扰动观测器和改进自适应二阶快速终端滑模的PMLSM伺服系统控制 被引量:1
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作者 赵希梅 李德豪 金鸿雁 《电机与控制学报》 EI CSCD 北大核心 2024年第4期41-49,共9页
针对永磁直线同步电动机(PMLSM)在运行时易受到摩擦力、负载扰动及环境变化等不确定影响,设计一种基于扰动观测器和自适应二阶快速终端滑模控制方法。首先,该方法在高阶滑模的基础上结合了快速终端滑模控制,有效加快了系统响应速度。其... 针对永磁直线同步电动机(PMLSM)在运行时易受到摩擦力、负载扰动及环境变化等不确定影响,设计一种基于扰动观测器和自适应二阶快速终端滑模控制方法。首先,该方法在高阶滑模的基础上结合了快速终端滑模控制,有效加快了系统响应速度。其次,在二阶滑模面的基础上引入条件积分项,该项仅作用于边界层内部,能够有效避免滑模到达阶段由于积分饱和现象导致的超调量过大及响应时间过慢的问题。此外,设计自适应切换控制律,使切换增益在合理的区间内,并根据系统状态进行实时更新,从而削弱抖振现象。最后,为进一步提升系统的鲁棒性,采用扰动观测器对PMLSM系统的集总不确定性进行补偿。经实验验证,该控制方法具有良好的位置跟踪精度和强鲁棒性,且对系统抖振现象有明显削弱作用。 展开更多
关键词 永磁直线同步电动机 二阶滑模控制 终端滑模控制 条件积分项 自适应控制 扰动观测器
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基于线性化潮流模型的配电网电压无功控制策略
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作者 杜晓东 李晓明 +3 位作者 韩思宁 李安昌 詹祥澎 杨军 《电测与仪表》 北大核心 2024年第4期41-47,共7页
针对现有基于二阶锥松弛的电压无功控制模型无法以电压波动为目标且求解速度较慢等问题,文中提出了一种基于线性化潮流模型的配电网电压无功控制策略。基于支路潮流方程建立了包含有载调压分接头、电容器组和光伏逆变器等调控手段的电... 针对现有基于二阶锥松弛的电压无功控制模型无法以电压波动为目标且求解速度较慢等问题,文中提出了一种基于线性化潮流模型的配电网电压无功控制策略。基于支路潮流方程建立了包含有载调压分接头、电容器组和光伏逆变器等调控手段的电压无功控制模型,并将其离散变量松弛为连续变量,以形成二阶锥规划。进一步以二阶锥规划所得结果为基准点构造线性化潮流模型,并以电压波动最小为目标,将连续变量还原为离散变量。最后基于改进的IEEE-33节点测试系统进行了仿真,仿真结果表明所提出的线性化潮流模型具有较高的精度和更快的求解速度,能够适用于配电网实时电压无功控制。 展开更多
关键词 主动配电网 电压无功控制 二阶锥松弛 线性化潮流 支路潮流模型
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压缩机用直线振荡电机频率跟踪控制
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作者 李伟业 宫逸凡 +2 位作者 徐伟 罗英露 何明杰 《电气传动》 2024年第1期9-14,共6页
作为一种新型压缩机,直线压缩机具有效率高、体积小、噪声和震动小的优势,但要发挥其效率高的优点,需对驱动频率进行控制,以跟踪其机械谐振频率。针对该特性,提出了一种基于二阶广义积分器(SOGI)和双相关相位检测算法的直线振荡电机频... 作为一种新型压缩机,直线压缩机具有效率高、体积小、噪声和震动小的优势,但要发挥其效率高的优点,需对驱动频率进行控制,以跟踪其机械谐振频率。针对该特性,提出了一种基于二阶广义积分器(SOGI)和双相关相位检测算法的直线振荡电机频率跟踪控制算法。该控制算法与基于位移电流积平均值(ASCP)的频率跟踪控制算法相比,具有动态响应快、变工况下运行稳定的优点,且增强了对外界干扰的抑制效果,提高了控制系统的稳定性。仿真和实验表明,所提出的控制算法可以快速跟踪电机固有频率,验证了理论的合理性和有效性。 展开更多
关键词 谐振频率跟踪 直线压缩机 二阶广义积分器 相位检测算法
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基于SOGI高频方波电压注入的永磁直线同步电机无感控制 被引量:1
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作者 王杰 张博 +1 位作者 张立昌 艾雄雄 《微特电机》 2024年第2期59-63,共5页
针对永磁直线同步电机的无感控制技术,为了解决传统高频方波注入法无法准确定位转子位置和转速的问题,提出了基于SOGI高频方波电压注入的无感方法。与传统的高频方波电压注入法不同,为了得到更好的高频电流信号,采用二阶广义积分器提取... 针对永磁直线同步电机的无感控制技术,为了解决传统高频方波注入法无法准确定位转子位置和转速的问题,提出了基于SOGI高频方波电压注入的无感方法。与传统的高频方波电压注入法不同,为了得到更好的高频电流信号,采用二阶广义积分器提取响应高频电流信号,采用正交锁相环解决反正切函数没有反馈直接放大噪声的影响。为证明无感控制技术的有效性,用Simulink进行了仿真验证。结果表明,基于SOGI高频方波电压注入的无感方法大大降低了误差,缩短了调节时间,提升了响应时间。 展开更多
关键词 永磁直线同步电机 二阶广义积分器 高频方波电压注入法 正交锁相环
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一类分式递推数列的极限求法
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作者 赵舵舵 陈萍萍 周恺 《高等数学研究》 2024年第6期23-25,35,共4页
文章针对数列极限存在性问题展开工作,特别是针对分式线性递推数列的极限求解进行了深入探讨.通过揭示数列与函数不动点之间的内在联系,应用特征方程方法,从化归、方程构建及函数分析等角度,提出了有效的求解策略.
关键词 二阶线性、非线性递推数列 化归 特征方程 母函数
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周期复合结构上的弹性二次特征值问题的多尺度渐近分析方法
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作者 王洪玉 马强 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期89-96,共8页
针对周期复合结构上的弹性二次特征值问题,本文提出了一种基于二阶双尺度(Second-Order Two-Scale, SOTS)方法的多尺度分析方法 .该方法考虑速度阻尼效应的二次特征值问题,给出了特征值、特征函数的二阶渐近展开,以及特征值的误差估计.... 针对周期复合结构上的弹性二次特征值问题,本文提出了一种基于二阶双尺度(Second-Order Two-Scale, SOTS)方法的多尺度分析方法 .该方法考虑速度阻尼效应的二次特征值问题,给出了特征值、特征函数的二阶渐近展开,以及特征值的误差估计.本文给出了方法的有限元实现,并通过近似值和参考解之间的定性和定量比较验证了方法的有效性.数值算例结果表明,特征值与特征函数中的二阶校正项对于重构单胞内特征函数的局部信息发挥着重要作用. 展开更多
关键词 周期复合结构 二阶双尺度渐近分析 二次特征值问题 线性化
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线性化模型下二阶逆变器的混沌控制 被引量:1
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作者 高志强 陈翰博 《电子测量与仪器学报》 CSCD 北大核心 2023年第3期152-160,共9页
针对线性化模型下二阶逆变器发生的非线性分岔与混沌行为,加入控制手段增加稳定域与抗扰性。首先构建了二阶逆变器的系数线性化迭代模型,运用分岔图、折叠图再现了其产生的混沌行为,并寻求系统的Jacobian矩阵和平衡点。然后加入延时反... 针对线性化模型下二阶逆变器发生的非线性分岔与混沌行为,加入控制手段增加稳定域与抗扰性。首先构建了二阶逆变器的系数线性化迭代模型,运用分岔图、折叠图再现了其产生的混沌行为,并寻求系统的Jacobian矩阵和平衡点。然后加入延时反馈控制,并基于朱里判据给出了控制参数的限定条件。最后为说明所加入混沌控制方法的优越性,开展了数值仿真模拟实验。结果表明,延时反馈控制使系统比例参数K的分岔值从0.573后移至0.973,且当直流源输入侧电压突变时,系统仍保持在稳定运行状态。表明施加延时反馈控制后,二阶逆变器运行的稳定域增加且整体的抗扰性增强。 展开更多
关键词 二阶逆变器 系数线性化模型 非线性动力学行为 混沌控制 延时反馈控制
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Linearization of Emden Differential Equation via the Generalized Sundman Transformations
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作者 Joel Mvendaga Orverem Yusuf Haruna +1 位作者 Bala Ma’aji Abdulhamid Magaji Yunbunga Adamu 《Advances in Pure Mathematics》 2021年第3期163-168,共6页
The Emden differential equation is one of the most widely studied and challenging nonlinear dynamics equations in literature. It finds applications in various areas of study such as celestial mechanics, fluid mechanic... The Emden differential equation is one of the most widely studied and challenging nonlinear dynamics equations in literature. It finds applications in various areas of study such as celestial mechanics, fluid mechanics, Steller structure, isothermal gas spheres, thermionic currents and so on. Because of the importance of the equation, the method of generalized Sundman transformation (GST) as proposed by Nakpim and Meleshko is used for linearizing the Emden differential equation. The Emden differential equation considered here is a modification of the equation given by Berkovic. The results obtained in this paper imply that the Emden equation cannot be linearized by a point transformation. The general solution of the modified Emden equation is also obtained. 展开更多
关键词 Emden Differential Equation second order Ordinary Differential Equation Generalized Sundman Transformation linearIZATION
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