系统函数

In presented method, the correlated variables are transformed into uncorrelated variables equivalently, and the performance functions in the correlated variables space are transformed into those in the equivalent uncorrelated variables space, in which the reliability sensitivity of the system failure probability with respect to the distribution parameters of the uncorrelated variables can be solved by the moment method for the uncorrelated variables. Finally the equivalent relationship between the correlated variables and the uncorrelated variables, the chain rule for derivative are employed to obtain the reliability sensitivity of the system failure probability with respect to the means of the correlated variables.

在所提的方法中，首先将相关变量空间等效转化为不相关变量空间，并将系统多个失效模式的功能函数转化为不相关变量空间的功能函数，进而利用矩方法得到多模式系统失效概率对不相关变量空间基本分布参数的灵敏度，最后利用相关变量空间与不相关变量空间的等价关系及复合函数求导法则，求得多模式系统失效概率对相关变量空间中变量均值的灵敏度。

In order to get the principle of cell distribution in buffer, the local rate function is obtained, which can be expressed in detail with the help of DuBoisReymond equation and conditional integral. This gives us the system's rate function.

为了能够分析缓存器中分组信息变化的规律，论文首先给出了主干系统的本地速率函数，利用变量积分的DuBois-Reymond方程，给出了本地速率函数所满足的微分方程，在条件积分的约束下求得本地速率函数表达式，由此求得系统的速率函数。

A sufficient condition that ensures the stability of the origin of the system is derived, and the domain of attraction may be enlarged by applying a fuzzy anti-windup compensator to the considered system.

构造了一个更一般的Lyapunov函数—模糊Lyapunov函数来分析系统的稳定性以及估计系统的吸引域，克服了寻求一个公共的正定矩阵P的困难，使用模糊Lyapunov函数得到的系统的吸引域估计保守性更小。

Then, the system is linearized by variational approach, the local null controllability is proved by applying a generalized implicit function theorem and combining the good property of the solution mapping.

首先通过对系统线性化，构造泛函，利用对偶方程，给出控制函数具体形式的办法得到系统的逼近能控性；然后采用变分方法对系统线性化，再结合解映射好的性质，应用推广的隐函数定理，证明系统的局部零能控性；最后利用局部零能控性和逼近能控性结合给出系统零能控的结论。

Compared with deterministic systems, the infinitesimal generator for the system is a second-order differential operation. In this dissertation, we designed the quartic control Lyapunov function and systematically design the state-feedback and output feedback adaptive controller using integrator backstepping methodology. The closed-loop system is asymptotically stable in the large.

与确定性系统相比，随机系统的Lyapunov函数的微分运算包含二阶导，所以设计适当形式的控制Lyapunov函数十分关键，本文设计了四次型的控制Lyapunov函数，并应用积分反推技术，给出了状态反馈及输出反馈自适应控制器和鲁棒自适应控制器的设计方法，证明了闭环系统概率意义下的渐近稳定性和有界稳定性。

In theory, firstly, the numerical simulation methods, such as the boundary element method, the finite difference method and the finite element method, were utilized to calculate the distribution of electric field intensity and potential of the electron-gun system, the focusing system and the whole equipment, respectively. Then, the trajectories of the electron-beam were traced by using of the Runge-Kutta method and the Monte-Carlo method associatively. The point spread function was also calculated.

在理论分析中，先后采用边界元方法、差分方法、有限元方法等科学数值计算方法，编制程序，对X射线源的电子枪发射系统、聚焦系统以及发射系统与聚焦系统的组合系统等的电场分布进行了严格的计算，在准确求得各系统电场内各个剖分点的电场场强、偏导数等参量的基础上，采用蒙特-卡罗模拟方法和不等距龙格-库塔方法相结合，追踪由LaB_6单晶阴极表面发射出的大量电子束在电场内的运动轨迹，求出点扩展函数，并根据点扩展函数的优劣，反复调节、大量计算对比，挑选出X射线源最佳的电极结构及其组合。

There exits several MDO algorithms. But they are in our opinion either nonefficient or complicated. So we devised an algorithm called Subspace Approximation Optimization . In the SAO algorithm, the whole system is decomposed into one system-level optimization and several disciplinary optimizations so that a large and complicated problem can be divided into several easy-solving sub-problems. The coupling relationships and the coordination among disciplines are presented by equality constraints and these equality constraints are assigned to relevant disciplines. The optimums of design variables in system level optimization are transferred to discipline level optimization. The optimums of design variables in discipline level correspond to the point that is the nearest to the optimums of design variables in system level. If the optimums of design variables in system level are out of feasible region of discipline 1eve1, linear constraints can be built in the system level optimization using the design variable optimums obtained by the discipline level optimization. The system level optimization would improve the design of the whole system with these linear constraints.

目前，国内外已经发展出了多种飞机多学科设计优化算法，本文的重点是针对协同优化算法的不足，提出了子空间近似优化算法(Subspace ApproximatingOptimization，SAO)，SAO算法中，整个系统的优化问题被分解成一个系统级优化和若干学科级优化，而各个学科之间的耦合与权衡关系则被当作等式约束，这些等式约束将被分配到各个学科级优化中去，系统级优化的任务是寻找整个系统的最优解，而学科级优化的目标函数是以系统级优化分配下来的设计点为圆心的超球半径的平方，因此，如果系统级优化分配下来的设计点在学科级优化可行域内，则学科级优化目标函数为0，反之，则学科级优化的最优点是系统级优化当前设计点距离可行域最近的点。

The closed-characteristic expression is proven to be of a A-class entire function and some related propositions are also given. Based on them a series of nathematic deviations are done, which brings an analytic expression between the controller parameters and the cost funtion as well as the restrictions on the optimization problem. In this way the original proposition is concretized for solving.

从系统的传递函数出发，首先证明系统闭环特征函数为A-类整函数的性质并给出其它有关定理，然后进行一系列数学推导，得出了控制器参数与目标函数间的解析关系式及优化的约束条件，由此产生参数优化的具体命题。

The first-part of this paper evaluates the main stability theories concerned and concludes the conceptualization steps and essentials covering the various methods. Different disturbed-measure functions are studied in terms of their formulations and characteristics. Both Lyapunov functions and TEFs can be constructed only in a heuristic way of case-by-case. Ignoring changes in the disturbed-measure function's value after clearing the fault, Lyapunov functions and TEFs are applicable to neither nonautonomous one-machine infinite-bus systems nor any multimachine systems. Moreover, TEFs cannot guarantee the sign of errors because they don't satisfy the conditions for Lyapunov functions.

作为第1篇，文中归纳出这3种方法的共同分析步骤和要素，并比较各种受扰程度函数，指出：李雅普诺夫函数和TEF的建立都必须从具体模型出发并只能依靠启发的方式，它们没有考虑受扰程度函数的值在故障清除后的变化，因此既不适用于复杂模型的单机系统，也不适用于任何多机系统；又由于这2种方法都基于很强的假设，故分析的误差可能非常大，而TEF法更是由于不满足李雅普诺夫函数的条件而可能得到冒进的结果。

Based on these, an improving μ-synthesis is presented, with which the high-purity distillation is designed well. 2. The robust performance problem of MIMO plant is explained with the plant direction angle, which shows that the robust performance varies with different input uncertainties and the μ-synthesis should be applied correctly according to the uncertainty structure. 3. Condition number and bandwidth are the important items for robust performance design in MIMO system. The H〓 two-block problems can not deal with the robust performance design of MIMO system because of the condition number cancellation. A general μ-synthesis procedure for MIMO system with uncertainties is presented. 4. For the SISO system, the object function in robust performance is amplified by at most 〓 than that of H〓 two-block problems in value: So the robust performance of SISO system can be done with the H〓 two-block problems to avoid the complicated μ-synthesis procedure. 5. All the conclusions and methods presented in this paper are demonstrated by some typical design examples.

从而形成一种改进的μ综合方去，并对精馏塔病态对象进行了鲁棒性能设计，得到令人满意的结果；（2）利用对象的方向角解释了MIMO对象鲁棒性能设计出现问题的原因，并提出不同输入摄动形式下系统的鲁棒性能问题也并不相同，因此利用μ综合处理鲁棒性能设计时，应根据不同的摄动情况采用不同的结构进行设计：（3）条件数问题和带宽问题是MIMO系统鲁棒性能设计的两个主要问题，指出由于条件数对消的存在使得一般H〓两块问题无法处理MIMO系统的鲁棒性能设计，而μ综合方法则是处理MIMO系统鲁棒性能设计的有效方法，并给出了其处理MIMO系统鲁棒性能设计的一般性方法；（4）提出对于SISO系统H〓两块问题（S/T问题、S/KS问题）的设计指标函数与鲁棒性能设计的μ指标函数在数值上最大差〓倍，因此对于一般SISO系统的鲁棒性能设计可以简单地用一般的H〓的两块问题处理，而避免μ综合设计的复杂过程；（5）本文中提出的结论和算法都利用H〓/μ发展中的典型例子：Doyle-Stein问题，Safonov的战斗机模型，精馏塔对象等进行了设计验证。

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％。