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In this study, a moment method improved by the third-order normal transformation polynomial for practical slope reliability analysis with random variables having unknown distributions is discussed.

5在实际的结构或岩土工程中，有学者提出用变量正态化转换多项式解决仅知道变量前几阶统计矩的可靠性分析问题。

The term 'Viking' was virtually unknown until the beginning of the nineteenth century (the first Oxford English Dictionary reference dates from 1807), and yet during that century the figure of the Viking, Vikingr, Vikinger, Vikingir, Vi-king, Vik-ing, Wiking, Wicking, Sea-King, Sea-Rover, Northman and Norseman came to feature prominently in numerous paraphrased sagas, prize essays, popular lectures, poems, plays, pious novels, papers in learned journals, and the like.

这个词'海盗'是几乎不为人所知，直到19世纪初（第一牛津英语词典参考日期由1807年），但在19世纪的数字海盗， Vikingr ， Vikinger ， Vikingir ，六景，维克，法， Wiking ，芯吸，海金，海，罗孚， Northman和诺斯曼来突出许多转述传奇故事，散文奖，大众讲座，诗歌，戏剧，虔诚的小说，论文的学术期刊等。

Such a genetic experiment might have astonished and delighted Darwin, who lamented in The Origin that "The laws governing inheritance are quite unknown." Not any longer.

这样的基因实验也许会让Darwin震惊和兴奋，因为他在《物种起源》中哀叹的"主宰遗传的法则完全不可琢磨"已经不是事实了。

If it is determined that the sender is an unknown sender, a knock notification message is generated.

如果确定发送者为未知发送者的话，则生成敲门信号通知消息。

A system and method is directed to providing a knock notification in response to a message from an unknown sender.

一种致力于响应来自于未知发送者的消息而提供敲门信号通知的系统与方法。

It can avoid overdoing the generalization.(3) Imputation of unknown values. To the incomplete information systems,the dissertation suggests a new method to impute the null values. The method is based on the extending model of rough sets and fully considers the consistence of data and dependency of attributes.

为了提高GDSS决策能力，本文提出了将粗糙集理论与层次分析法相结合的思想，利用粗糙集理论所确定的属性间的依赖关系，分析应用系统运行所积累的大量数据中各决策因素、决策者对决策目标的影响，构造具有完全一致性的个体判断矩阵和综合判断矩阵，建立自学习系统，克服决策者主观因素对决策结果的影响。

This thesis is divided into six parts. The first chapter is preface, the current status of research in the inverse problems for parabolic partial differential equations is reported; the second chapter is "regularization methods for numerical differentiation and their applications ", in this chapter we investigate many regularization methods from a viewpoint of regularization theory and algorithm, some applications in the inverse problems for parabolic partial differential equations are given; the third chapter is "spectral regularization methods". Based on Fourier analysis, within the framework of regularization theory, we apply the spectral methods to some ill-posed problems. Many numerical experiments are done in order to show the validity of the methods; the fourth chapter is devoted to wavelet dual least squares method and a revised wavelet method; in the fifth chapter,we combine finite difference method with method of lines and apply it to the backward heat conduction problem in time; in the sixth chapter "identification problems for unknown source ", the essence and the degree of two problems related to source identification are pointed out, at the same time, some numerical methods are reported.

本文分为六个部分，第一章前言简要分析了国内外抛物型偏微分方程反问题的研究现状；第二章数值微分的正则化及其应用从正则化理论和算法的角度出发，考察了许多正则化方法，还给出了数值微分在抛物型偏微分方程反问题的一些应用；第三章谱正则化方法是在Fourier分析的基础上，在一般正则化理论的框架下，给出了这种方法在各种不适定问题中的应用，数值实验表明谱方法是有效的；第四章研究了小波对偶最小二乘方法和改进的小波方法；第五章主要研究了有限差分方法结合线方法在时间反向热传导问题中的应用；第六章是未知源识别问题，主要指出了两类未知源问题的不适定程度和不适定本质，同时报告了一些数值方法。

It is problems that the integral initial values are unknown and how to eliminate the error with the numerical integral in reversion for detecting structure damage.

积分初值的未知、消除数值积分引入的误差是结构损伤反演计算中信号处理的难题。

The problem of PI controller design for the multi-input and multi-output system is transformed to that of static output feedback controller design via the new state variable. As to the problem of the static output feedback, a new LMI-based sufficient condition of the controller is presented in this thesis. We can gain the multivariable PI controllers just solving one LMI inequality. The numerical example is provided to illustrate the proposed design approach. 3.The H_∞ robust control is able to solve the multivariable problem, also the control problem characteristic of the modeling error, parameters uncertainties and unknown perturbation, Its application research in the power electronics is beginning now. Considering the characteristics of the PWM DC-DC converters, a multivariable PI controllers which is based on H_∞ Performance Index is designed.

通过构造新的状态变量，可以将多输入多输出系统的PI控制器设计问题转化为静态输出反馈控制问题，利用后者的成熟理论来设计控制器；本文在问题转化后采用更为简便的算法，只需通过求解一个LMI不等式，就能求取基于H_∞性能指标的多变量PI控制器参数，实例验证了算法的有效性。3.H_∞鲁棒控制具有处理多变量问题的能力，可解决具有建模误差、参数不确定和干扰未知系统的控制问题；它在电力电子学中的应用研究刚刚开始。

Up to forty years ago, this date was virtually unknown amongst collectors in the Colony but since that time, and with increasing interest now being shown in numismatics by more and more people, a few tenths specimens have come to light.

四十年前，本港的集币家还未发现这一年的硬币，但从那时起，对钱币学有兴趣的人越来越多，数十枚这种硬币的样本也随之被发现。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷