搜索结果: 1-15 共查到“知识库 微分动力系统”相关记录42条 . 查询时间(2.817 秒)
具非对称位势二阶Hamilton系统的同宿轨
Hamilton系统 同宿轨 临界点理论
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2018/10/8
运用三临界点定理研究了一类二阶Hamilton系统同宿轨的存在性.在位势函数是非对称假设下,建立了一个新的存在性准则,改进了已有文献的结果.
一种基于MCU的图形组态设计研究
MCU 组态软件 图形显示
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2018/9/30
传统的图形显示界面,一般通过程序直接绘制到显示屏,逻辑组态程序与实现程序实现耦合度高,如果需要修改界面,则需通过修改大量代码来实现,这样导致程序复杂,重复性劳动多,开发周期长,不利于核电领域图形组态软件的开发;基于计算机监控系统的图形组态软件虽然可通过图形化编程方便的获取和修改显示界面,但由于计算机监控系统功耗高、体积大,在某些环境中有所限制,为了解决这些问题,将图形组态软件在计算机中设计好的图形...
基于速度反馈分数阶PID控制的达芬振子的主共振
分数阶比例-积分-微分控制 达芬振子 主共振 平均法
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2018/12/29
与传统整数阶比例-积分-微分(PID)控制器相比,分数阶比例-积分-微分控制器由于增加了两个控制参数,因此能够更灵活地控制受控对象.研究了基于速度反馈分数阶比例-积分-微分控制的达芬振子的主共振,利用平均法获得了系统的近似解析解.研究发现分数阶比例-积分-微分控制器的比例环节以等效线性阻尼的形式影响系统的共振振幅,积分环节以等效线性阻尼和等效线性刚度的形式影响系统的动力学特性,微分环节以等效线性阻...
描述不确定动态系统的新工具:不确定微分方程
动态系统 新工具 微分方程
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2013/11/11
不确定微分方程是由不确定过程驱动的一类微分方程,是一种新的描述不确定动态系统的数学工具.本文系统地介绍了不确定微分方程的研究现状.概括了几类可求解析解的不确定微分方程,并对不易求得解析解的不确定微分方程,介绍了一种求近似解的数值解法.为了更好地用不确定微分方程描述不确定系统,给出了不确定微分方程的存在唯一性定理和稳定性定理.最后介绍了不确定微分方程在经济系统及金融系统等方面的应用.
微结构金属光栅在LED光提取中的应用
微结构金属光栅 LED 近场倏逝波 表面等离子
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2013/8/14
微结构金属光栅可用于增强LED的发光效率, 应用不同的金属材料则表现出不同的光谱辐射特性, 使得不同金属材料的微结构光栅对同一波长的光提取效率不同. 基于时域有限差分(FDTD)法, 计算了在LED芯片内应用不同金属材料的微结构光栅时, LED的光提取增强特性. 通过分析金属材料的介电特性和产生表面等离子(SPs)效应的品质因子, 发现带内跃迁等离子频率越高的金属材料, 由于其自由电子数多, 越接...
利用数值模拟方法对高超声速钝锥及Apollo返回舱底部尾迹流场进行了研究, 分析尾迹流动的失稳过程. 对钝锥模型, 在M∞=6, Re=1.71× 106(Re以球头半径为参考长度)条件下观察到了底部流动的不稳定性. 不添加任何扰动, 数值模拟首先得到的流动是稳定解, 在底部发展出一个主分离区和一个二次分离区, 流动是轴对称状态. 继续进行计算, 发现二次分离线率先变形, 底部流场发展出非定常周期...
Nonlinear dynamics of two coupled nano-electromechanical resonators
Nonlinear dynamics coupled nano-electromechanical resonators
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2011/7/6
As a model of coupled nano-electromechanical resonantors we study two nonlinear driven oscillators with an arbitrary coupling strength between them. Analytical expressions are derived for the oscillat...
Voltage Collapse and ODE Approach to Power Flows: Analysis of a Feeder Line with Static Disorder in Consumption/Production
ODE Voltage Collapse Feeder Line Power Flows Static Disorder
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2011/7/6
We consider a model of a distribution feeder connecting multiple loads to the sub-station. Voltage is controlled directly at the head of the line (sub-station), however, voltage anywhere further down ...
Complete chaotic synchronization and exclusion of mutual Pyragas control in two delay-coupled Rössler-type oscillators
complete synchronization time-delayed feedback control delay chaos R¨ossler model electronic circuits
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2011/7/6
Two identical chaotic oscillators that are mutually coupled via time delayed signals show very complex patterns of completely synchronized dynamics including stationary states and periodic as well as ...
Observation of depth-induced properties in wave turbulence on the surface of a fluid
wave turbulence fluid surface depth-induced properties
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2011/7/7
We report the observation of changes in the wave turbulence properties of gravity-capillary surface waves due to a finite depth effect. When the fluid depth is decreased, a hump is observed on the wav...
Exact nonequilibrium steady state of a strongly driven open XXZ chain
nonequilibrium steady state driven XXZ chain
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2011/7/7
An exact and explicit ladder-tensor-network ansatz is presented for non-equilibrium steady state of an anisotropic Heisenberg XXZ spin-1/2 chain which is driven far from equilibrium with a pair of Lin...
Kinematic dynamo simulations of von Kármán flows: application to the VKS experiment
von Kármán flows Kinematic dynamo simulations VKS experiment
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2011/7/7
The VKS experiment has evidenced dynamo action in a highly turbulent liquid sodium von K\'arm\'an flow [R. Monchaux et al., Phys. Rev. Lett. {\bf 98}, 044502 (2007)]. However, the existence and the on...
Applications of Classical Scaling Symmetry
Classical Scaling Symmetry second-order differential equation conservation laws central field dynamics
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2011/7/7
Any symmetry reduces a second-order differential equation to a first-order equation: variational symmetries of the action (exemplified by central field dynamics) lead to conservation laws, but symmetr...
Urban chaos and replacement dynamics in nature and society
bifurcation chaos fractal dimension logistical map replacement dynamics Volterra-Lotka’s model urbanization
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2011/7/7
Many growing phenomena in both nature and society can be predicted with sigmoid function. The growth curve of the level of urbanization is a typical S-shaped one, and can be described by using logisti...
Pole solutions in formation of the Saffman-Teylor "finger" with one half of the channel width without surface tension
surface tension integro-differential motion equations Laplacian growth
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2011/7/5
Laplacian growth without surface tension has nice analytical solutions which replace its complex integro-differential motion equations by simple differential equations of poles motion in a complex pla...