扰动

Digital PLL's linear mathematical model is established, and it's stability is analyzed, then the DPLL's stability conditional expression is given. Whereas the phase lock in UPS is very particular, this dissertation emphasizes on the dynamic performance with disturbance of the utility source's frequency noise and the reference phase.

基于UPS 锁相的特殊性，着重分析了市电频率扰动以及相位给定突变时的系统动态特性，仿真分析表明在同一个数字锁相环中，锁相误差抖动小与输出频率变化不能过快，二者不可兼得。

This paper focuses on the node stability of eco\|industrial symbiosis system from the view of environmental economics, and set up the Node Symbiotic Economics Model on the enterprises of eco\|industrial symbiosis system by analyzing relationship on the pollutants recycle of the inter\|node interconnected enterprises. Through the observation of the supply change in the enterprise′s recycling contaminants at the node based on the mathematical solutions to the model, the effects of outside disturbances on the balance of supply and demand has been studied. If the elasticity of the product price is equal to or less than 1, the node can achieve conditional stability and if the elasticity of the product price is more than 1, the node will fluctuate periodically around a stable point, and even chaos can appear.

从环境经济学角度出发，以生态产业共生系统的节点稳定性为研究内容，通过节点间相互关联的企业之间的污染物循环利用的关系分析，建立生态产业共生系统中企业之间的节点间污染物循环利用共生经济学模型，在市场经济条件下，基于模型的数学解，通过观察节点处对污染物进行循环利用企业受市场经济影响导致的产品供给变化，研究系统外界市场经济扰动对节点污染物循环利用的供需平衡的影响。

Based on the equilibrium equation of an arch element the cubic nonlinear dynamic model with second order is established and the nonlinear differential dynamic system without constant term is obtained through a transfer process of T=U+b. Hence three fixed points and the homoclinic orbits are found. The critical condition of the chaotic vibration of the elastic arch is given by using the method of Melnikov function. The numerical results of the stationary and chaotic motion are given and discussed.

首先利用拱的单元平衡方程建立了拱的二阶三次非线性动力学模型；然后通过变换使方程转化为不含常数项的非线性微分动力系统，并由此得到无扰动系统的3个不动点与同宿轨道；再用Melnikov函数法给出了发生混沌的临界条件；最后给出了该系统出现定常运动和混沌运动的数值结果。

Both DSC and RMT150B experiment system gives continuous and stable curve of stress-strain including its post peak part.

扰动状态理论结果和RMT150B岩石实验系统得到的实验结果都可以给出稳定的、连续的、包括软化段的应力应变关系曲线。

Furthermore, the first-order optimality condition and its equivalent reformulations for generalized semi-infinite max-min programming with a non-compact set are presented using the lower-Hadamard directional derivative and subdifferential.2. Chapter 3 studies the gradient-type methods for unconstrained optimization problems. Section 1 proposes a new class of three-term memory gradient methods. The global convergence property of the method is established. Furthermore, in order to improve the convergence property of the method, a new class of memory gradient projection methods is presented with the property that the whole sequence of iterates converges to a solution to the problem under the conditions such as pseudo-convexity and continuous differentiability of objective function. In section 2, two new classes of methods, called gradient-type method with perturbations and hybrid projection method with perturbations, are proposed. In these methods, non-monotone line search technique is employed, which makes them easily executed in computer.

第3章研究了无约束优化问题的梯度型算法，第1节提出了一类新的三项记忆梯度算法，讨论了算法的全局收敛性，进一步提出了一类新的具有更好收敛性质的记忆梯度投影算法，并证明了该算法在函数伪凸的情况下具有整体收敛性，第2节在非单调步长搜索下提出了带扰动项的梯度型算法及其混合投影算法，这两类算法的一个重要特征就是步长采用线搜索确定而不象许多文献中那样要求步长趋于零，这样更容易在计算机上实现，在较弱的条件下证明了这些算法的全局收敛性，数值算例表明了算法的有效性。

In this paper, a method of chaos controlling based on variable structure control was developed.

变结构控制是一种很成熟的非线性控制方法，其特点是对扰动和误差具有很强的鲁棒性。

Methods The theories of topology, convex analysis and functional analysis are used to study and analyze some properties of the set-valued function in the problem.

依据拓扑，凸分析和泛函分析的理论，对于锥扰动向量优化问题中特定的集值映射进行分析和研究。

Based on LMI method and convex combination technique, the problem of robust stabilization for a class of uncertain switched systems with nonlinear disturbance is studied.

基于线性矩阵不等式方法和凸组合技术，研究一类带有非线性扰动的不确定切换系统的鲁棒镇定问题。

The switching law is given out according to convex combination condition and the sufficient condition of the stabilization is obtained by switching among a finite number of controllers under the assumption that a single controller cannot make the systems stable and has H-infinity disturbance attenuation.

在假定每个单一的控制器均不能使系统稳定且具有H扰动衰减度的条件下，利用凸组合条件给出了切换律的设计方案，通过在有限个控制器间的切换得到了镇定的充分条件。

Necessary and sufficient conditions of the robust positively invariant sets are established for the linear discrete-time system family specified by matrix convex polyhedron and additive interval disturbances.

对由矩阵凸多面体和加性区间扰动描述的线性时变离散系统族，得到了鲁棒正不变集的充分必要条件；对非线性系统族则得到有关充分条件。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。