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THE ESTIMATION OF SOLUTION OF THE BOUNDARY VALUE PROBLEM OF THE SYSTEMS FOR QUASI-LINEAR ORDINARY DIFFERENTIAL EQUATIONS
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作者 黄蔚章 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第8期745-754,共10页
This paper deals with the singular perturbation of the boundary value problem of the systems for quasi-linear ordinary differential equationswhere x,f, y , h, A, B and C all belong to Rn , and g is an n×n matrix ... This paper deals with the singular perturbation of the boundary value problem of the systems for quasi-linear ordinary differential equationswhere x,f, y , h, A, B and C all belong to Rn , and g is an n×n matrix function. Under suitable conditions we prove the existence of the solutions by diagonalization and the fixed point theorem and also estimate the remainder. 展开更多
关键词 systems of the quasi-linear ordinary differential equation singular perturbation DIAGONALIZATION asymptotic expansion
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Parallel Implementations of Modeling Dynamical Systems by Using System of Ordinary Differential Equations
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作者 Cao Hong-qing, Kang Li-shan, Yu Jing-xianState Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072,Hubei,ChinaCollege of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期229-233,共5页
First, an asynchronous distributed parallel evolutionary modeling algorithm (PEMA) for building the model of system of ordinary differential equations for dynamical systems is proposed in this paper. Then a series of ... First, an asynchronous distributed parallel evolutionary modeling algorithm (PEMA) for building the model of system of ordinary differential equations for dynamical systems is proposed in this paper. Then a series of parallel experiments have been conducted to systematically test the influence of some important parallel control parameters on the performance of the algorithm. A lot of experimental results are obtained and we make some analysis and explanations to them. 展开更多
关键词 parallel genetic programming evolutionary modeling system of ordinary differential equations
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NONDEGENERACY OF POSITIVE SOLUTIONS TO HOMOGENEOUS SECOND-ORDER DIFFERENTIAL SYSTEMS AND ITS APPLICATIONS 被引量:1
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作者 戴求亿 Christopher C. Tisdell 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期435-446,共12页
This article considers the Dirichlet problem of homogeneous and inhomogeneous second-order ordinary differential systems. A nondegeneracy result is proven for positive solutions of homogeneous systems. Sufficient and ... This article considers the Dirichlet problem of homogeneous and inhomogeneous second-order ordinary differential systems. A nondegeneracy result is proven for positive solutions of homogeneous systems. Sufficient and necessary conditions for the existence of multiple positive solutions for inhomogeneous systems are obtained by making use of the nondegeneracy and uniqueness results of homogeneous systems. 展开更多
关键词 Second ordinary differential system Dirichlet problem positive solution NONDEGENERACY multiplicity result
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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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Construction of Periodic Solutions of One Class Nonautonomous Systems of Differential Equations
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作者 Alexander N. Pchelintsev 《Journal of Applied Mathematics and Physics》 2013年第3期1-4,共4页
In this article we proposed a method for constructing approximations to periodic solutions of one class nonautonomous system of ordinary differential equations. It is based on successive approximation scheme using par... In this article we proposed a method for constructing approximations to periodic solutions of one class nonautonomous system of ordinary differential equations. It is based on successive approximation scheme using parallel symbolic calculations to obtain solutions in analytical form. We showed the convergence of the scheme of successive approximations on the period, and also considered an example of a second order system where the described scheme of calculations can be applied. 展开更多
关键词 Periodic Solution system of ordinary differential EQUATIONS Scheme of Successive APPROXIMATIONS SYMBOLIC CALCULATIONS
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Discretized Multisplitting AOR Waveform Relaxation Algorithms for Initial Value Problem of Systems of ODEs
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作者 谷同祥 李文强 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期27-35, ,共9页
The multisplitting algorithm for solving large systems of ordinary differential equations on parallel computers was introduced by Jeltsch and Pohl in [1]. On fixed time intervals conver gence results could be derived ... The multisplitting algorithm for solving large systems of ordinary differential equations on parallel computers was introduced by Jeltsch and Pohl in [1]. On fixed time intervals conver gence results could be derived if the subsystems are solving exactly.Firstly,in theis paper,we deal with an extension of the waveform relaxation algorithm by us ing multisplittin AOR method based on an overlapping block decomposition. We restricted our selves to equidistant timepoints and dealed with the case that an implicit integration method was used to solve the subsystems numerically in parallel. Then we have proved convergence of multi splitting AOR waveform relaxation algorithm on a fixed window containing a finite number of timepoints. 展开更多
关键词 systems of ordinary differential equations initial value problems multisplitting algorithm AOR method waveform relaxation algorithm
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DFA-ODENets:面向周期多阶段复杂系统的预测仿真框架 被引量:1
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作者 李潇睿 宁春宇 +1 位作者 袁兆麟 班晓娟 《工程科学学报》 EI CSCD 北大核心 2024年第1期137-147,共11页
部分复杂系统受内外部因素影响在运行时会呈现出周期性的阶段变化,且在不同阶段具有完全不同的动态特性.因此在使用数据驱动方法解决此类系统的预测和仿真问题时,使用单一结构模型难以准确地学习系统在不同阶段的动态特性.本研究提出了... 部分复杂系统受内外部因素影响在运行时会呈现出周期性的阶段变化,且在不同阶段具有完全不同的动态特性.因此在使用数据驱动方法解决此类系统的预测和仿真问题时,使用单一结构模型难以准确地学习系统在不同阶段的动态特性.本研究提出了基于确定性有限状态机-常微分方程网络的预测仿真框架(DFA-ODENets),以建模周期多阶段系统.该模型由多个ODENet组成,每个ODENet能够从不规则采样的序列数据中学习系统在各个阶段内的动态特性.同时模型集成了基于确定性有限状态自动机思想的阶段转换预测器以实现模型预测时在不同阶段之间自动转换.最后,将DFA-ODENet框架应用于某计算中心制冷系统的预测仿真场景中.模型能够在给定系统运行过程中的服务器负载和环境温度下模拟系统运行过程,并对系统的制冷功率、进气口温度等主要输出变量进行预测.其中,对于制冷系统能耗预测的平均相对误差在5%以内.同时,利用制冷系统仿真模型优化了系统停止制冷时的温度设定值,通过仿真实验表明该优化最高可以节省18%的制冷能耗. 展开更多
关键词 复杂系统建模 周期多阶段系统 神经常微分网络 多输入多输出时间序列预测 制冷系统 能耗优化
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A Multiplicity Result of Positive Solutions for a Class of Multi-parameter Ordinary Differential Systems
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作者 Xi-you CHENG Xiao-lin YAN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2012年第4期653-662,共10页
In this paper, we establish a result of Leray-Schauder degree on the order interval which is induced by a pair of strict lower and upper solutions for a system of second-order ordinary differential equations. As appli... In this paper, we establish a result of Leray-Schauder degree on the order interval which is induced by a pair of strict lower and upper solutions for a system of second-order ordinary differential equations. As applications, we prove the global existence of positive solutions for a multi-parameter system of second-order ordinary differential equations with respect to parameters. The discussion is based on the result of Leray- Schauder degree on the order interval and the fixed point index theory in cones. 展开更多
关键词 positive solution ordinary differential system fixed point index
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非自治常微分p-Laplacian系统周期解的存在性 被引量:1
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作者 张申贵 《河北科技师范学院学报》 CAS 2012年第3期28-33,62,共7页
研究了非自治常微分p-Laplacian系统的周期解的存在性。当具有p-线性增长非线性项时,利用临界点理论中的鞍点定理得到了系统周期解存在性的充分条件,所得结果推广了已有结果。
关键词 常微分p-laplacian系统 周期解 临界点理论
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含参量一阶线性时变常微分系统状态的几个性质
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作者 陈章红 《遵义师范学院学报》 2024年第3期84-87,共4页
文章针对含参量线性时变常微分系统,研究其参变量对系统状态的影响,并探求含参变量的微分系统状态的性质。基于参变量集合的特点和点集Hausdorff距离,主要得到以下两方面的结果:其一,在参变量集非空条件下,线性时变常微分系统状态集是... 文章针对含参量线性时变常微分系统,研究其参变量对系统状态的影响,并探求含参变量的微分系统状态的性质。基于参变量集合的特点和点集Hausdorff距离,主要得到以下两方面的结果:其一,在参变量集非空条件下,线性时变常微分系统状态集是凸紧的;其二,在Hausdorff距离意义下,含参量时变常微分系统的状态依时间是连续的。 展开更多
关键词 线性时变常微分系统 含参变量 系统状态 凸紧 连续
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POSITIVE SOLUTIONS OF BOUNDARY VALUE PROBLEM FOR A SYSTEM OF NONLINEAR ORDINARY DIFFERENTIAL EQUATIONS 被引量:19
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作者 LiHongyu SunJingxian 《Annals of Differential Equations》 2005年第2期153-160,共8页
By using topological method, we study a class of boundary value problem for a system of nonlinear ordinary differential equations. Under suitable conditions, we prove the existence of positive solution of the problem.
关键词 systems of ordinary differential equations topological method positive solution
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Positive solutions for a multi-parameter system of second-order ordinary differential equations 被引量:4
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作者 CHENG XiYou ZHANG ZhiTao 《Science China Mathematics》 SCIE 2011年第5期959-972,共14页
In this paper, we establish the product formula for the fixed point index on product cone, andthen, as applications, consider the existence, nonexistence and multiplicity of positive solutions for a second-order ordin... In this paper, we establish the product formula for the fixed point index on product cone, andthen, as applications, consider the existence, nonexistence and multiplicity of positive solutions for a second-order ordinary differential system with parameters. The discussion is based on the product formula and thefundamental properties of the fixed point index. 展开更多
关键词 positive solution ordinary differential systems fixed point index
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THE QUALITATIVE CLASSIFICATION OF A SPECIAL TYPE OF HIGHER ORDER ORDINARY DIFFERENTIAL SYSTEM
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作者 李东梅 《Annals of Differential Equations》 1997年第3期232-247,共16页
In this paper, a theorem of the local qualitative classification of equllibrium of a special type of higher order ordinary differential system is provided for establishing the theoretical bases to extend the planer. ... In this paper, a theorem of the local qualitative classification of equllibrium of a special type of higher order ordinary differential system is provided for establishing the theoretical bases to extend the planer. qualitative nomgraphy in [1] to the special geometricaljy qualitative method in 3-dimensions. 展开更多
关键词 Higher order ordinary differential system EQUILIBRIUM Locally topological equivalence Hartman theorem
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MULTIPLICITY OF SOLUTIONS TO ASYMPTOTICALLY LINEAR SECOND-ORDER ORDINARY DIFFERENTIAL SYSTEM
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作者 Yucheng Bu(Dept. of Teachers’ Training,Zhenjiang College,Danyang 212300,Jiangsu) 《Annals of Differential Equations》 2011年第3期283-292,共10页
In this paper,we consider an asymptotically linear second-order ordinary differential system with Dirchlet boundary value conditions. Under some conditions,we show the multiplicity of solutions to the system by the Mo... In this paper,we consider an asymptotically linear second-order ordinary differential system with Dirchlet boundary value conditions. Under some conditions,we show the multiplicity of solutions to the system by the Morse theory and an index theory. 展开更多
关键词 second-order ordinary differential systems index theory of linear systems Morse theory multiplicity of solutions
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Modelling the Dynamical State of the Projected Primary and Secondary Intra-Solution-Particle Movement System of Efavirenz In-Vivo 被引量:1
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作者 Tafireyi Nemaura 《International Journal of Modern Nonlinear Theory and Application》 2016年第4期235-247,共13页
This work seeks to describe intra-solution particle movement system. It makes use of data obtained from simulations of patients on efavirenz. A system of ordinary differential equations is used to model movement state... This work seeks to describe intra-solution particle movement system. It makes use of data obtained from simulations of patients on efavirenz. A system of ordinary differential equations is used to model movement state at some particular concentration. The movement states’ description is found for the primary and secondary level. The primary system is found to be predominantly an unstable system while the secondary system is stable. This is derived from the state of dynamic eigenvalues associated with the system. The saturated solution-particle is projected to be stable both for the primary potential and secondary state. A volume conserving linear system has been suggested to describe the dynamical state of movement of a solution particle. 展开更多
关键词 ordinary differential Equations Stability Nonautonomous Linear system Concentration-Varying Eigenvalues Solution Particle
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On the Existence of Periodic Solutions for a Nonlinear System of Ordinary Differential Equations
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作者 Zhaoli Liu Department of Mathematics,Shandong University,Ji’nan,250100,P.R.China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2000年第3期505-514,共10页
This paper is concerned with the existence of periodic solutions for a nonlinear system of ordinary differential equations.We obtain a Nagumo-type a priori bound for the periodic solutions and then by using this a pri... This paper is concerned with the existence of periodic solutions for a nonlinear system of ordinary differential equations.We obtain a Nagumo-type a priori bound for the periodic solutions and then by using this a priori bound we prove the existence of at least one T-periodic solution under some general conditions 展开更多
关键词 Nonlinear system of ordinary differential equation Periodic solution a priori estimation Nagumo condition
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基于常微分系统的甘蔗收获机控制系统研究
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作者 张福珍 申腾飞 《农机化研究》 北大核心 2023年第6期213-216,222,共5页
为进一步提高轮式甘蔗收获机的收获效率,针对其作业对象特点与蔗地环境,应用常微分控制技术进行收获系统优化研究。基于其结构组成与作业流程,就实现关键组件的常微分控制要求建立相适应的数学模型,并完成实际算法应用布局与收获核心部... 为进一步提高轮式甘蔗收获机的收获效率,针对其作业对象特点与蔗地环境,应用常微分控制技术进行收获系统优化研究。基于其结构组成与作业流程,就实现关键组件的常微分控制要求建立相适应的数学模型,并完成实际算法应用布局与收获核心部件优化。进行常微分控制机理下的轮式甘蔗收获机收获效率试验效果测定,结果表明:轮式甘蔗收获机的系统控制准确度得到提升,堵塞率与含杂率降低,蔗段合格率可达92.85%,满足大于90.00%以上的相关设计规范,整机收获效率相对提高了9.30%,验证了该常微分控制应用于甘蔗收获机系统设计的适用性,可为类似收获装备效率提升研究提供借鉴。 展开更多
关键词 甘蔗收获机 控制系统 常微分系统 含杂率
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常微分方程生物动力系统正性及耗散性研究方法
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作者 刘胜强 马宁涓 《大学数学》 2023年第1期6-12,共7页
常微分方程生物动力系统解的正不变性和耗散性是对该类型动力行为刻画的先决条件,具有重要的基础作用.针对常微分方程生物动力系统这些共性问题的研究方法进行系统的归纳,分别对Kolmogorov型及非Kolmogorov型常微分方程生物动力系统典... 常微分方程生物动力系统解的正不变性和耗散性是对该类型动力行为刻画的先决条件,具有重要的基础作用.针对常微分方程生物动力系统这些共性问题的研究方法进行系统的归纳,分别对Kolmogorov型及非Kolmogorov型常微分方程生物动力系统典型实例的正不变性和耗散性研究进行全面总结,并应用于近年来生物动力系统前沿领域的相关研究. 展开更多
关键词 常微分方程 生物动力系统 正不变性 耗散性
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非线性动力系统刚性方程精细时程积分法 被引量:16
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作者 孔向东 钟万勰 《大连理工大学学报》 CAS CSCD 北大核心 2002年第6期654-658,共5页
讨论了非线性动力系统刚性常微分方程的数值积分算法,给出了非线性动力系统刚性方程的单步精细时程积分法.揭示了精细时程积分不仅具有显式积分格式,而且具有绝对稳定性和高精度的特点,避免了刚性方程的计算危险性.算例进一步表明了精... 讨论了非线性动力系统刚性常微分方程的数值积分算法,给出了非线性动力系统刚性方程的单步精细时程积分法.揭示了精细时程积分不仅具有显式积分格式,而且具有绝对稳定性和高精度的特点,避免了刚性方程的计算危险性.算例进一步表明了精细时程积分算法求解刚性方程的有效性. 展开更多
关键词 非线性系统 动力学 常微分方程 刚性常微分方程 数值积分
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动态系统的演化建模 被引量:19
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作者 曹宏庆 康立山 陈毓屏 《计算机研究与发展》 EI CSCD 北大核心 1999年第8期923-931,共9页
针对采用传统方法解决动态系统的微分方程建模问题所遇到的困难和存在的不足,文中设计了将遗传程序设计与遗传算法相嵌套的混合演化建模算法,以遗传程序设计优化模型结构,以遗传算法优化模型参数,成功地实现了动态系统的常微分方程... 针对采用传统方法解决动态系统的微分方程建模问题所遇到的困难和存在的不足,文中设计了将遗传程序设计与遗传算法相嵌套的混合演化建模算法,以遗传程序设计优化模型结构,以遗传算法优化模型参数,成功地实现了动态系统的常微分方程组建模过程自动化.计算实例表明:采用此算法能在合理的运行时间内由计算机自动发现多个较优的常微分方程组模型,和现有的建模方法(如灰色系统方法)相比较,它具有建模过程智能化与自动化、模型结构更加灵活多样、方法适用性更广、数据拟合和预测的精度更高等优点. 展开更多
关键词 动态系统 演化建模 灰色系统 微分方程组
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