扰动

The evolution of frontal rainbands happening during the frontogenesis induced by deformation field is investigated through the numerical cloud model. Besides, in order to get insight from the results of numerical simulations, the semigeostrophic frontogenesis model is used to investigate the effect of diabatic heating on the frontogenesis and the analytical method of WKBJ is used to study the influence of large-scale deformation field and frontal circulation on the development of symmetric disturbance happened in the frontal zone.

为了加深对数值模拟结果的理解，还利用半地转模式对非绝热加热影响锋生的过程进行了讨论，通过WKBJ方法讨论了变形场锋生条件下对称扰动的发展，从中可以了解大尺度变形场和锋生环流对中尺度扰动的作用，这方面的工作可以对前面非静力数值模拟结果的理解提供帮助。

Nowadays,the properties of sediments changed by bioturbation have been concerned by International Geosphere and Biosphere Plan, especially the problems about the bioturbation and hydrodynamic coupling led to the tidal flat sediment flow differences.

如今，生物扰动对潮滩沉积物性质的改变已越来越引起国际地圈、生物圈计划的关注，尤其是生物扰动和水动力的耦合作用影响潮滩沉积物渗流差异问题。

In many physical situations, the Hamiltonian of the system is composed of an unperturbed Hamiltonian and a perturbation.

在很多物理情况下，系统的哈密顿量由未扰动哈密顿量与扰动势两部分所组成。

The effect of upper tropospheric perturbation PV on the development of the South-West Meso-cyclogenesis is discussed on Hoskins PV Principle in terms of conservation of PV on isobaric surface and humid isentropic PV.Upper tropospheric perturbation PV,which dilates slantwise downward and southward,is found to be an important factor to influence the low-level South-West Mesocyclone.

基于Hoskins位涡理论思想从等压面位涡守恒和湿等熵位涡守恒的角度来研究对流层高层位涡扰动对低层西南涡的发生发展影响，发现对流层高层位涡扰动是影响西南涡发生发展的重要因素，它对西南涡的影响表现出它有向南向下倾斜伸展的特点。

When the temperature changes, several device parameters such as the transmittance, the extinction ratio and the curve of the transmittedintensity will change accordingly for devices made of the Iceland crystal.

其次系统分折了温度对格兰·泰勒棱镜和格兰·付科棱镜的透射光强曲线的影响，利用光的干涉原理和不同振动形式的反射比公式，得到了格兰棱镜在同一入射波长、温度改变时的扰动因子极大值点的移动量以及相同的温度改变、不同人射波长时扰动困子极大值点的移动量。

In our thesis, contents are organized as following In Chapter 1 we present our topic's internal and overseas research situations, theoretical and practical significance, and introduce the research object and contents, and the main contributions of this dissertation. Chapter 2 reviews the development of the stability results for nonlinear systems and some relevant recent results, which include Lyapunov and LaSalle-Yoshizawa theorems for nonlinear systems, and stochastic edition for stochastic nonlinear systems. Sontag's formula for systems affine in control is presented in the frame of CLF. The concepts of disturbance attenuation and the inverse optimality are also explained in this Chapter. In chapter 3 we present the solvable theorem of inverse optimal gain assignment problem, design the inverse optimal controller and the inverse optimal tracking controller for strict-feedback nonlinear continuous systems with unknown time-varing bounded disturbances and constant unknown parameters using an adaptive backstepping algorithm, which are nonlinear, continuous and are easier to realize. These designs are fully systematic and the algorithm can be directly coded in symbolic software. The results of simulation show the effectiveness of the control algorithms.

论文的结构如下：在第1章中，给出了本文研究课题的研究现状、理论意义和实际应用，并介绍了本文的研究对象、研究内容以及主要贡献；在第2章中，针对确定性非线性系统和随机非线性系统，分别介绍了Lyapunov定理、LaSalle-Yoshizawa定理及其随机版本；对仿射系统，在控制Lyapunov函数框架下，给出了Sontag公式；同时给出了非线性系统扰动抑制和逆最优控制问题的基本概念；在第3章中，针对具有未知时变有界扰动和未知定常参数的一类不确定非线性系统，给出并证明了逆最优增益配置可解定理，使用自适应Backstepping算法和均值定理，系统地设计了自适应逆最优控制器和逆最优跟踪器，这种设计方法可同时获得逆最优控制策略和自适应律，简单明了，仿真结果表明该控制算法的有效性，并给出了性能估计。

The technique of perturbations constraint when applied to degree reduction of Bézier curves gives fairly well results This paper discusses why these kind of technique have limitation when applied to B-spline curves, and the least squares approximation approach is presented for reducing the degree of B-spline curves Examples comparing the new method with existing ones are illustrate

将扰动约束技术应用于B啨zier曲线的降阶给出了理想的结果讨论了将这类方法应用于B样条曲线降阶时结果不理想的原因，提出了采用最佳平方逼近技术对B样条曲线做降阶运算的方法；并用实例对该方法和基于扰动约束的降阶方法进行了比

An incremental-iterative method based on the Newton-Raphson method combined with constant arc length of incremental displacement vector is employed for the solution of nonlinear equilibrium equations. The subspace iterative method is used for the solution of natural frequencies and vibration modes for the free vibration of beam structures.

本研究推导元素的节点惯性力时，先将元素扰动位移表示成当前固定元素座标的扰动位移和旋转之函数，故可直接求得元素的节点惯性力，元素的一致性质量矩阵可由元素节点的惯性力对元素节点的加速度微分求得。

The optimization problem with linear inequalities can be solved by Quadratic Programming. The simulation results show that the design improves the dynamic performance and suppress torsional vibration causing by rolling perturbation. The model predictive control suppresses rolling perturbation.

仿真结果表明，采用具有约束条件的预测控制策略的控制系统对轧机传动系统的控制效果在动态性能和抑制扭振效果上明显优于传统PI控制，可以较好的抑制轧制扰动对传动系统产生的影响，对解决轧制扰动鲁棒性控制问题是一种有效的解决办法。

By using Flash software produced a number of fluid flow in the animation, including the viscous flow in vivo experiments indicate friction, rotation speed Dengjiao containers of liquids in relative balance, the system and control of, weak disturbance in the transmission space - Mach cone, the disturbance wave Dissemination process, bypassing the wings of the two-dimensional flows, ease converter and blast crisis and stagnation flow indicate parameters and critical parameters such as the concept that a number of animation, produced by sports meeting between the animation, shape meeting between animation, masking animation and time Axis to achieve those effects the flow of fluid animation, and by adding these buttons used to control the flow of fluid animation, and so will the speed of the fluid flow in a clear show up.

本文利用Flash软件制作了流体若干流动现象的动画，包括粘性流体内摩擦实验示意、等角速旋转容器中液体的相对平衡、系统与控制体、微弱扰动在空间的传播——马赫锥、扰动波传播过程、绕过机翼的二维流动、缓变流与急变流示意以及滞止参数和临界参数的概念说明等若干动画，通过制作运动补间动画、形状补间动画、遮罩动画和时间轴特效来实现这些流体流动的动画效果，并通过添加按钮用于控制这些流体流动的动画的速度等将上述流体流动现象清晰的展示出来。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐