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In addition, some modifications on several computational methods are also presented. Using LMTO method the electronic structure of several systems are studied, and some results are obtained. They are: The ideal Nb (100) surface has three surface states, the multi-layer relaxed surface has two surface states. The surface energy of the ideal surface is higher than that of the relaxed surface, that means that the multi-layer relaxed surface is more stable than the former one, which supports the LEED results. The mono-layer relaxed Ag (111) surface is the most stable one among several" stable surface models"presented by several researchers. The surface energy of Ag (111) surface is higher than that of surface Ag (001), which supports some experimental results such as different reaction rate at different surface orientations for the same material. The surafce states of Si (111) surface not only locate near the Fermi level, but also in the valence band, which agrees well with Cohen's conclusion. Si (111)-H is an effective model for analysing the surface states and H adsorbed on the back surface is a good method for improving the convincingness of the results obtained on thinner slab models. The surface stability depends on three different kinds of MoSi〓(001) surfaces, the surface with mono-layer Si is the most stable one, and the surface with Mo at the first layer is the most unstable one among them. These are consistant with the Kemoda's experimental results. The valence bands of clean or K adsorbed CdTe (111) surface agrees well with the synchrotron radiation studies. The surface of CdTe (111) consists of four kinds of surface models which show different surface electronic structures and different surface structure stabilities. The conclusion agrees well with Wu's experimental work. The different absorbed alkali metals on the CdTe (111) surface give different adsorption characteristics which have relations not only with the valence electrons, but also with the core ones of the alkali metals. The electonic structures of Si-C alloys are different from that of Si-Ge alloys, and the energy band gaps of Si-C alloys do not increase linearly with Carbon concentration, our conclusion supports Alexander's results, but conflicts with Soref's one.

现分述如下： LMTO方法及其应用方面：1）通过对Nb（100）表面电子态分析发现清洁理想表面有三个表面态，多层弛豫表面有两个表面态；表面能大小说明多层弛豫表面更稳定，支持了LEED结果。2）通过对采用不同方法获得的几种不同Ag（111）表面稳定结构的表面能计算分析，给出了单层弛豫表面为Ag（111）表面的最稳定结构；从Ag（111）单层弛豫表面和Ag（001）表面的表面能比较，发现了Ag（001）表面表面能要比Ag（111）小的，表明了同种物质不同表面取向将表现出不同物理、化学性质，这是与实验中得出的结论是吻合的，3）通过对Si（111）表面态分析，不仅发现了Si（111）表面不仅具有居于费米能级附近的悬挂键所对应的表面态，而且还有很多表面态位于价带能量范围内，与Cohen等结果一致，H饱和slab模型背表面相当于增加了slab层的厚度，是一有效的变相增加slab层厚的方法，弛豫表面较清洁理想表面价带谱们低能端的少许移动，预示着总能降低，说明弛豫表面较清洁理想表面稳定。4）MoSi〓具有三种表面，从费米能级上态密度值大小得到单层Si表面最稳定，Mo原子为表层原子的表面最不稳定，双层Si原子表面居中的结论，这与Kemoda等人实验结果是一致的。5）通过对CdTe（111）表面表面电子态、表面结构稳定性及表面H、碱金属吸附的电子结构系列研究，不仅得出了CdTe（111）清洁及碱金属K吸附价带谱与同步辐射光电子谱相吻合的结果，而且发现了CdTe（111）表面具有四类不同原子近邻特征，表现出四类不同的表面结构及电子结构特征：不同表面态分布、不同的表面结构稳定性（表层原子与次层原子成三键有一悬挂键的表面要比表层原子与次层原子成一键有三悬挂键稳定（与Wu等人实验结果一致））、不同的H吸附特性。

Based on description method of damping motion in mechanical vibration, variables movement of generator are divided into two basic motion models: damping oscillation and critical damping motion. Detail methods of extracting damping parameters from simulation data is introduced to establish variable motion models. An approximate method is put forward to simulate low-frequency signal and generator response characteristic, from which motion models and damping parameters of main variables are obtained. The influences of oscillation amplitude, frequency and initial operating point of power system to the motion damping parameters are analyzed.

借鉴机械振动中阻尼运动的描述方法，将低频振荡下发电机主要变量的运动归纳为阻尼振荡和临界阻尼两种基本运动形态；介绍了从仿真数据提取阻尼参数建立参数运动模型的方法，实现对发电机振荡特性的量化分析；提出一种系统侧低频振荡信号的近似模拟方法，并应用于发电机响应仿真，获得了主要变量的运动模型和阻尼参数；分析了系统侧振荡幅度、频率以及初始工况对发电机功角振荡的影响。

It solves the problem that the unitary contour presentation can not correctly extract face contour in a face image which suffers from scale, rotation etc. The definition of the internal and external energy function is provided. At the same time, the global matching algorithm and local matching algorithm is given. The experiment shows that this presentation and the accompanying matching algorithm can be used to extract the face contour very well. So the image segmentation can be implemented by using it.②By analyzing the recognition principle of PCA method, we can conclude that the face images coming from different surrounding consist of different face image space. This is the essential reason that makes the generality of PCA method worse. Also, we give a measurement means to measure the distance from different face image space, so we can analyze face image space more conveniently.③We also construct various scale models and rotation pose models to detect the scale and rotating angle of face image to be recognized. The experiment results show that the detecting precision is very high. So it is good for face image feature extraction and face image representation.④Similarly, we construct local feature models of face image and utilize them to detect the local feature of face image. At the same time, we put forward a novel face image local feature detection algorithm, locating step by step. The experiment results show that this method can accurately detect the location of local face feature in a image.⑤A novel face image presentation model, dual attribute graph , is put forward. Firstly, it utilizes attribute graph to present the face image, then exact the local principal component coefficient and Gabor transform coefficient of thc pixels which corresponds to the nodes of the graph as the attribute of the nodes. This representation fully makes use of the statistical characteristic of the local face feature and utilizes Gabor transform to present the topographical structure of face image. So DAG has more general property.⑥Based on the DAG presentation, we give a DAG matching function and matching algorithm. During the design of the function and algorithm, the noise factor, e. g., lighting, scale and rotation pose are considered and tried to be eliminated. So the algorithm can give more general property.⑦A general face image recognition system is implemented. The experiment show the system can get better recognition performance under the noise surrounding of lighting, scale and rotation pose.

本文在上述研究的基础上，取得了如下主要研究成果：①构造了一个通用的人脸轮廓模型表示，解决了由于人脸图象尺度、旋转等因素而使得仅用单一轮廓表示无法正确提取人脸轮廓的问题，并给出了模型内、外能函数的定义，同时给出了模型的全局与局部匹配算法，实验表明，使用这种表示形式以及匹配算法，能够较好地提取人脸图象的轮廓，可实际用于人脸图象的分割；②深入分析了PCA方法的识别机制，得出不同成象条件下的人脸图象构成不同的人脸图象空间的结论，同时指出这也是造成PCA方法通用性较差的本质原因，并给出了不同人脸空间距离的一种度量方法，使用该度量方法能够直观地对人脸图象空间进行分析；③构造了各种尺度模板、旋转姿势模板以用于探测待识人脸图象的尺度、旋转角度，实验结果表明，探测精确度很高，从而有利于人脸图象特征提取，以及图象的有效表示；④构造了人脸图象的各局部特征模板，用于人脸图象局部特征的探测；同时提出了一种新的人脸图象局部特征探测法---逐步求精定位法，实验结果表明，使用这种方法能够精确地得到人脸图象各局部特征的位置；⑤提出了一种新的人脸图象表示法---双属性图表示法；利用属性图来表示人脸图象，并提取图节点对应图象位置的局部主成分特征系数以及Gabor变换系数作为图节点的属性，这种表示方法充分利用了人脸图象的局部特征的统计特性，并且使用Gabor变换来反映人脸图象的拓扑结构，从而使得双属性图表示法具有较强的通用性；⑥在双属性图表示的基础上，给出双属性图匹配函数及匹配算法，在函数及算法设计过程中，考虑并解决了光照、尺度、旋转姿势变化等因素对人脸图象识别的影响，使得匹配算法具有较强的通用性；⑦设计并实现了一个通用的人脸图象识别系统，实验结果表明，该系统在图象光照、尺度、旋转姿势情况下，得到了较好的识别效果。

Next, a few important friction models in common use are discussed, including six static and seven dynamic friction models. The forms, characteristics and applicability of these models are discussed in detail.

其次， 系统地介绍了几种较为重要的、常用的摩擦模型，包括6种静态摩擦模型和7种动态摩擦模型，并对每一种模型的构成，特点和适用范围等进行了较为详细地论述。

First of all, because the teaching the definition of Frequency and Equiprobability models are basic knowledge of Probability, and they lay a solid foundation for the subsequent studying probability, the method of computer imitation trials in the teaching of Frequency has obvious effect, so does the audio-visual models in the teaching of Equiprobability models.

首先，频率定义与古典概型是概率的基础知识，并且为概率的后续学习提供坚实基础，因此它们的教学尤为重要。

In advance of reviewing probability for Senior Three students, the author gave an exam of probability. On the basis of analyzing the results, the author carried out a group of teaching strategies, the author reviewed the definition of Frequency by computer imitation trials and Equiprobability models by various Probability models, and distinguished Exclusive Events and Independent Events by examples, and described Variable Distribution by means of various Probability models.

在高三概率复习前夕，进行一次概率测试，在测试分析的基础上，采取有针对性的教学策略，利用计算机模拟试验复习频率定义；用各种模型进行古典定义的教学；运用实例辨析互斥事件与相互独立事件；借助各种概率模型描述随机变量分布列。

The heat transfer models, flow models and the physical equations, which are of small calculating error and less limit for the parameters used, are also considered as the subsidiary models.

辅助模型包括考虑了各种流型及强迫循环与自然循环等各种因素的传热模型、流动模型以及精心挑选的参数覆盖范围大，误差小，计算方便的物性方程等。

There are totally five chapters in the paper. Chapter 1 is the introduc-tion,and extreme value theory and methods and modelling for returns fat tails are introduced systematically in Chapter 2.This chapter also presents mean excess function and de Haan's moment estimate to decide on the reasonable exceedance threshold. Chapter 3 describes in detail non-linear time series mod-els such as GARCH models and the corresponding statistical inferences,and it also gives modelling and statistical analysis methods for returns series. Chap-ter 4 uses the models in Chapter 2 to analyzes the daily returns for Shanghai complex index and Shenzhen complex index in the Shanghai and Shenzhen stock markets. Chapter 5 applies the models in Chapter 3 to the volatility analysis of the two stock indices returns.

论文总共五章：第一章是引言部分；第二章系统介绍了极值理论方法和收益率厚尾的建模方法，给出了平均剩余函数法和de Haan矩估计相结合的方法确定合理的超越门限；第三章详细论述了非线性时间序列模型GARCH类模型及其统计推断，并且给出了收益率时间序列波动的建模和统计分析方法；第四章利用第二章的模型对国内沪深两市大盘指数上证综指和深证综指日收益率数据分布的厚尾进行了实证分析；第五章将第三章的模型应用到两个股指日收益率时间序列的波动分析。

Two kinds of models by estimating pool equations and panel estimation have been constructed. Based on the idea of Reduced Form Model, by adopting lags-adjustment or not, time-series dynamics models of the fluctuation of urban residential real estate market, in which the endogenetic and the exogenous sensitive variable include, have been estimated. In logarithmic form the models are applied in a case.

同时，借助缩约模型的基本思想，将住宅市场波动的外生和内生敏感性因素纳入到城市住宅市场的动态分析中，从纵向角度引入非时滞调整和时滞调整的两类模式，构筑了不同形式的住宅市场波动的时序动态模型，采用对数模型估算案例城市商品住宅市场的时序动态波动状况。

Exponential family nonlinear models, or generalized nonlinear models are generalized from generalized linear models and nonlinear regression.

指数族非线性模型或广义非线性模型是广义线性模型和正态回归模型的自然推广。

Green function defined inphase space differs from one in coordinate space by its struc-ture which exhibits nonlocatity in coordinates and oscillatorybehavior with respect to momenta.

在相空间中定义的Green函数不同于通常坐标空间的Green函数，在结构上显示出对坐标的高度非局域性，而对动量则显示出振荡行为。

The upper front part of a saddle;a saddlebow.

前鞍桥马鞍前面的上部分；前鞍桥