控制理论

The coercivity follows the cubic equation with the content of carbon nanotube. Based on the classical hysteresis theory, a new inclusion theory with the cylinder morphology is developed, combined with stress theory the expression of coercivity is given.

基于传统的磁滞机理，发展了具有圆柱形状杂质的含杂理论，结合应力理论，给出了复合材料的矫顽力的表达式，不同体积含量的碳纳米管的复合材料的磁滞机理由含杂理论和应力理论协同控制。

The analysis results show the differential geometry method is effective for controlling chaos of power system and its control property is better than that of other methods.

研究表明：采用微分几何方法能够对电力系统的混沌行为进行有效控制，控制效果与其他混沌控制方法相比，具有明显的优越性。理论分析和数值仿真结果都证明了该控制方法的有效性。

Generalized predictive control is a kind of advance control methods that is of strong robustness, can overcome the time delay of system effectively and is suitable to unstable non-minimum phase system. But it has the shortcoming of large computation load because of online solving the Diophantine equation, inverse matrix and recursion solution by Least squares. So four kinds of fast algorithms of GPC that don't need the mathematical model of plant and are highly real-time are proposed in the paper. They have laid the rationale for the application of GPC to systems that need fast response.

广义预测控制是一种鲁棒性强、能够有效地克服系统滞后、可应用于开环不稳定非最小相位系统的先进控制算法，但由于它需要Diophantine方程计算、矩阵求逆和最小二乘的递推求解，因此计算量很大，本文针对此缺陷提出四种不基于对象模型且实时性高的广义预测控制快速算法，为广义预测控制应用于实时性要求高的快速系统奠定了理论基础，具体研究工作如下。

To further enhance the autoleveling technology of drawing frame, a new type of dual open-loop control system was issued based on the analysis of the quality of the current autoleveling control system of drawing frame. This paper presented a mathematical model of the new control system, analyzed its mathematical theory, and elucidated the theoretical basis of dual open-loop autoleveling control system.

为进一步提高并条机自调匀整技术，在分析纺织并条机自调匀整控制系统优劣的基础上，提出一种新的双开环控制系统，给出了新型控制系统的数学模型，详细分析了其数学原理，阐述了双开环自调匀整控制系统的理论基础。

As a result, the concept of an optimal set of elementary siphons is proposed and also the algorithm which can be finished in polynomial time to find such a set. With the set of optimal elementary siphons, net supervisors can generally produce maximalreachable states.

但是上述理论虽然只需要控制基本信标即可以控制整个系统，但是由于从属信标满足一定的可控性条件才能完全受控，这意味着在控制算法的生成过程中所有的信标都要参与，从而大大增加了系统控制的复杂性。

Based on the approximation expression of the oil film force of CSFD presented in chapter 6 for the short bearing, effectiveness of the active vibration control of CSFD on the rigid rotor、flexible rotors with one disk and two disks are studied both theoretically and experimentally.

在第六章推导出了CSFD在短轴承π油膜假设下油膜力的计算公式之后，分别从理论及试验两方面详细地分析了CSFD对刚性转子、单盘柔性转子、双盘柔性转子系统的振动进行分段控制的控制作用；讨论了不同的控制规律、切换滞后、切换次数以及转子角加速度等对控制效果的影响，以及在双稳态区切换时转子运动的方向性问题。

The existing control strategies of the fresh food compartment/freezer compartment prior based on the temperature control of the two-circuit cycle refrigerator-freezers with parallel evaporators were analyzed.

分析了现有蒸发器并联双循环冰箱采用基于温度的冷藏室优先的控制策略，提出了基于温度与分时运行联合控制的控制策略，并对该控制策略进行了理论分析。

This paper mainly consists of three parts:(1) Based on the Reddy's higher-order shear deformation plate theory and general von Kármán-type equations, put forward the governing equations of pre- and post-buckled vibration of several hybrid FGM plate forms which have not been studied adequately, triumphantly applying the perturbation technique combined with Galerkin method into equations solving, and get the comparatively simple result forms with complicated deduction at last;(2) As a new type of materials, piezoelectric fiber reinforced composite actuators were applied to optimal vibration control, interrelated informatons be depicted in this paper;(3) During the investigative cource, some factors not been considered adequently in other researches were discussed fully in the postbuckled vibration analysis, such as the temperature-dependent material coefficients, heat conduction and nonlinear vibration characteristic etc.

本文的研究工作主要包括：(1)基于Reddy高阶剪切变形板理论和广义Kármán型方程，给出了几类现有研究成果较少或没有彻底解决的FGM混合板结构的屈曲前和屈曲后振动特性研究的控制方程，成功将摄动-Galerkin混合法应用于求解过程，并给出了各控制方程相对直观且易于计算的解析解形式；(2)单向压电纤维增强复合材料(Piezoelectric Fiber Reinforced Composite，简称PFRC)是一种新型压电材料，本文将其应用到了结构振动控制研究当中，发现通过压电纤维体积含量的选择可以实现混合板结构的优化振动控制；(3)围绕几种有代表性的FGM混合板结构，讨论其屈曲后的振动特性，在分析中同时考虑热传导，材料物性参数的温度相关性，以及机/热/电荷载耦合效应对非线性振动特性的影响，最后给出了大量数值计算结果。

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。

Presents the design of longitudinal control for ASTOVL lift-fan aircraft, a multi-variable, strong-coupling, complicated nonlinear system to make the system nonlinear offset and decouple, and the method used for linear system in designing the system to gain expectant flying qualities and the combination of aerodynamic control surfaces with thrust vectors to delay the control surfaces getting into saturation, and the minimum N-norm generalized inverse theorem of weighted generalized inverse adopted to apportion the moments commands, which make the control surfaces gain appropriate deflection and the simulation results to verify the dynamic inverse control laws designed really make the system nonlinear offset and decouple; when one command is given, only this output will response, and others do not response; when all commands are given together, the responses will be just the linear superpose of the response of each command, therefore the operation of the pilot will be simplified greatly.

摘 要： ASTOVL升力风扇飞机是多变量、强耦合、复杂的非线性系统，采用非线性动态逆理论设计控制律以实现系统的非线性对消及解耦，然后，采用线性系统的设计方法对系统进行设计，以使系统获得期望的飞行品质。同时，考虑到ASTOVL升力风扇飞机是由气动舵面和推力矢量融合作用的，为了延缓各舵面进入饱和的时间，采用加权广义逆中的极小N-范数广义逆定理分配力矩指令，从而使各舵面达到适当的偏转角。并将所设计的控制律进行了仿真，结果验证了所设计的动态逆控制律使系统实现了非线性对消和解耦，单个指令作用时，只有该项响应，其余不受影响；所有指令作用时，其结果就等于单个指令作用时的线性叠加，这样使驾驶员的操纵大大简化而易于控制，从而大大降低了飞行事故率。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。