系统函数

As substitute for fluorite lens, a double-layer DOE is used in a long focal-length apochromatic objective lens. The modulation transfer function of this hybrid optical system is suggested for evaluating diffraction efficiency of the multilayer DOE. The results show the diffraction efficiency has a wide and symmetrical distribution in the whole waveband.

利用双层衍射光学元件替代萤石透镜校正混合光学系统的二级光谱，设计并制作了一套长焦距物镜，并利用系统调制传递函数评价了多层衍射光学元件衍射效率，测试结果表明衍射效率在整个设计波段内以较高的数值平均分布。

In this method, two fuzzy logic systems are used to approximate unknown functions, and an error compensator is designed to reduce the influence of approximation error on tracking accuracy.

针对一类非线性系统提出了间接自适应模糊控制方法，该方法用模糊逻辑系统逼近未知函数，并设计误差补偿器来减少逼近误差对跟踪精度的影响。

A SVM approximator is constructed to monitor the behavior of dynamic system according to in-suit learning of the nonlinear fault function.

主要通过在线学习故障特性对系统进行监测，利用SVM的ε-不敏感损失函数控制SVM的输出，抑制模型不确定性的影响，从而提高故障诊断系统的鲁棒性。

We have proposed the switching adaptive control law for the systems and designed the Lyapunov function in this thesis. It is proved that the proposed switching adaptive control law guarantees the solutions of the nonlinear systems boundedness and convergence of the tracking error to a residual set based on the Lyapunovs stability theory. The residual set can be made arbitrarily small by choosing a certain design parameters.

文中设计出了这类系统的切换自适应控制律，并构造出相应的Lyapunov函数，基于Lyapunov稳定性理论证明了系统在所设计的控制律作用下，闭环信号都有界并且跟踪误差收敛到一个集合，通过选择适当的参数可使这个集合任意小。

In this paper,by using the comparison theorems and constructing suitable Lyapunov function, the sufficient conditions are obtained for the permanence and existence of globally asymptotically stable positive periodic solution of the system.

研究了具有反馈控制的n种群非自治周期竞争系统的持续性，利用微分不等式并构造适当的Lyapunov函数得到系统存在惟一、全局吸引的正周期解的充分条

This paper consists of three parts: Firstly, we discuss a nonautonomous -species two-patches cooperative Lotka-Volterra diffusion system. Using Brouwer fixed-point theory and Liapunov function, under some conditions, we obtain that the system has a unique globally asymptotically stable positive periodic solution. Secondly, we consider a kind of nonautonomous predator-prey model, in which preys are with stage structure and the predator are with two patches.

中文摘要：本文分三部分讨论三类生态模型周期解或概周期解的存在性及全局渐近稳定性等内容：第一部分讨论了两斑块种群的互惠Lotka-Volterra扩散系统，运用不动点理论和构造Liapunov函数，得到了系统存在唯一一个全局渐近稳定的正周期解的充分条件。

With this method, the controller of the PWM DC/DC converter is designed. Utilizing augmented matrix to build a tracking control model with no steady error, and through select weighted matrix to perform the no overshoot and dynamic response of system.

通过引入增广矩阵，增加了控制量U*中对误差的积分环节，推导了无静差跟踪控制系统模型；在目标函数的构成参量和形式确定之后，通过选取适当的加权矩阵，实现系统的无超调动态响应。

In chapter 3, the two-dimensional nonautonomous Volterra-Lotka competition equations are considered which are continuous almost automorphic in time.

指出在相同的假设条件下，如果系统的系数函数是连续几乎自守的，则该系统存在一个几乎自守解。

The thesis first probably explains BrushLess Direct Current Motor, and discusses the related control methods, explains the background and Meaning of back electromotive force which is used in the thesis.

本文首先对无刷直流电机进行了概述，并对其相关控制方法进行了讨论，说明本文所采用反电动势法的背景和意义；接着论述了无刷直流电机基本组成环节、基本工作原理、运行特性和传递函数，然后是详述本文研究的重点：基于反电动势法的MATLAB调速系统的仿真以及基于反电动势法的DSP控制系统的实现。

The thesis first probably explains BrushLess Direct Current Motor, and discusses the related control methods, explains the background and Meaning of back electromotive force which is used in the thesis.Then the thesis expounds the basic component parts,the basic running principle,the running characteristic and transfer function of the BLDCM.And then the thesis detailedly dissertates its research pivot: the simulation of BLDCM system in MATLAB based on the method of Back-EMF and the control system of Digital Signal Processor based on the method of Back-EMF.

本文首先对无刷直流电机进行了概述，并对其相关控制方法进行了讨论，说明本文所采用反电动势法的背景和意义；接着论述了无刷直流电机基本组成环节、基本工作原理、运行特性和传递函数，然后是详述本文研究的重点：基于反电动势法的MATLAB调速系统的仿真以及基于反电动势法的DSP控制系统的实现。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。