模型理论

In rough sets based on accessible relation, we merge rough set theory and accessible relation into one model. Compared with classical rough set models(including Pawlak rough set model and various precise rough set model), the new model is more general.

基于可达关系的粗糙集模型是将可达关系应用于粗糙集理论中，这种模型比传统的粗糙集模型(Pawlak模型和可变精度粗糙集模型)更一般，将粗糙集理论推广到一般的方法论。

The proposed method has the merit that the numerical characteristics of stochastic temperature field response can be obtained by analyzing the random temperature field just in one time.3. Perturbed numerical algorithm of nonprobabilistic convex set theoretical models on the temperature fieldThe uncertain parameters of physical parameters and initial boundary conditions of heat conduction are described by the convex model. The perturbation formulas of the upper and lower bounds of temperature field response with unknown-but-bounded parameters are given via the combination of matrix perturbation theory and the convex set theory model.4. Numerical analysis for transient temperature field with interval parametersConsidering the uncertainties of the transient heat transfer, the physical parameters and initial boundary conditions are regarded as interval variables.

该方法具有只进行一次随机温度场分析便可以获得其响应的数字特征的优点。3、温度场的非概率凸集合理论模型的摄动数值解法将结构导热的物理参数、温度场的初始和边界条件等不确定性参数以凸模型加以描述，基于矩阵摄动理论和处理不确定问题的凸集合理论模型的结合，导出有界不确定参数瞬态温度场响应所在集合的上、下界摄动计算公式。4、具有区间参数的瞬态温度场数值分析考虑结构瞬态热传导问题的不确定性，将结构各物理参数和温度的初、边值条件均视为区间变量。

Firstly, this paper investigated roundly the basic theory of the ambient vibration method, analyzed systematically the main methods of ambient vibration identification, and discussed their advantages and disadvantages. Then we established the finite element model of structural dynamics and test model and analyzed their mutual relation, improved MUSIC method and correlation function method in the harmonic identification, and gave the subspace method and correlation function method based on continuous model, which is multi-harmonic retrieve technique. And then, this paper also puts forward least-squares method to estimate directly structural physical and modal parameters; this approach replaced the derivative operator in the continuous time model with an equivalent approximation, and estimated the physical parameters of structures by the least-squares method. And then, we discussed the approximation methods of derivative and their convergence. Finally, this paper researched the modal parameters of a frame structure by the simulation and test. The results demonstrated that subspace method, correlation function method and the least-squares method are effective and stable respectively.

全面地研究环境振动识别方法的基本理论，系统地分析环境振动识别方法的主要方法，讨论它们的优点和不足；建立结(来源：6666AB44C论文网www.abclunwen.com)构动力学的有限元模型和试验模型，分析有限元模型与试验模型之间的相互关系；改进谐波识别中的MUSIC识别方法和相关函数识别方法，给出大型结构模态识别的连续型的子空间分解识别方法和相关函数识别方法，这个方法是多元谐波识别方法；提出直接识别结构的物理参数和模态参数的最小二乘方法，这个方法利用导数的近似值代替导数值，并运用最小二乘方法识别结构的物理参数，讨论导数近似值的选择方法，分析算法的收敛性；通过仿真计算和模型实验，研究高层框架结构的模态参数识别，验证子空间分解识别方法、相关函数识别方法和最小二乘识别方法的有效性，算法的稳定性；从理论和试验两个方面分析和研究噪声对识别精度的影响，影响识别精度的因素，以及部分模态成分的模态参数不能够被识别的原因。

The main problems researched in the dissertation and achievements are as follows: The dissertation explains the science background and the theoretical and actual meaning of the task. The progress and the problems of the flow imaging technique are briefly explained. The advantages of electrical capacitance tomography are discussed. The paper discusses the formation and operating principle of ECT, and builds up the definite mathematical model by detail theoretical analyse, and establishes the Finite Element Model of the system by changing the finite boundary value problem of ECT into equivalence variation problem according to variation principle. On the basis of the FEM of the system, the paper builds the finite element model of the capacitance sensitivity field distribution and programs its finite element simulation software and proves the validity of the FEM of the ECT from different aspects. With the FEM and the qualitative analyse of the effect of each structural parameter of the capacitance transducer on its capability, this paper optimizes the structural parameters of the capacitance transducer, and obviously improves its capability. The compare of the simulated result with the static experimental result shows that the error of them is less than 0.9%.

其主要研究内容包括：阐述课题研究的学术背景及其理论与实际意义，概括总结出流动层析成像技术的发展现状和存在的问题，指出电容层析成像技术的优点；讨论电容层析成像系统的组成及工作原理，进行详尽的理论分析，以变分原理为基础，将ECT的有限元边值问题转换为等价的变分问题，从而建立系统的有限元模型；在系统有限元模型的基础上，建立敏感场的数学模型，编制有限元的仿真软件，并从不同角度证明电容层析成像系统有限元模型的正确性；利用有限元模型，定性地分析电容传感器各结构参数对其性能的影响，并对传感器结构参数进行优化设计，使其性能得到明显的改善。8电极ECT系统的仿真和静态实验结果的比较表明，它们之间的相对误差小于0。

The stiff exchange rate regime in China before the reform of RMB exchange rate regime on July, 21, 2005 - little volatility of RMB exchange rate, the inconvertibility of RMB under the capital account are the major factors and the lack of effective historical data which are responsible for limits on the research in this regard. The real exchange rate of RMB, therefore, is chosen as the objective of this study.

首先，文章对汇率的理论研究进行了回顾，提出了使用时间序列的一元自回归模型，然后，在对实际汇率的理论研究，以及人民币实际汇率本身所具有的特点进行分析的基础上，选择使用线性自回归模型和非线性的制度转换模型中的自我激励门限自回归模型和平滑过渡自回归模型来描述实际汇率的动态行为特征。

The result tells that at the beginning of English learning, semantic competence plays a major part in causing pragmatic failure while in the senior stage; social cognitive competence is the major cause. The thesis based on the research result establishes a semiotic Competence Cultivating Teaching Model in which markedness theory ,theory of interlanguage and interculture and content teaching approach are used to improve semiotic competence and reduce pragmatic failure.

研究结果也对语言学习者和教授者提出了一个新的问题，即在语言教学过程中，如何适当考虑语义能力，解释能力和社会认知能力三者的关系，构建一个教学模型，可以把这三者整体纳入语用能力培养的方案之中，笔者尝试性的提出一个解决方案，借用当前的词义习得标记性理论，过渡语与过渡文化理论和内容教学法理论，构建了一个符号能力发展模型，认为该模型将有利于学习者提高符号能力，进而减少语用失误。

First of all, the valuation errors in TXO of the BS-IV model are the smallest among all volatility models. In the whole, the BS-IVmodel underprices the market value, BS-HV, BS-EV（EGARCH（1,1））and Ad hoc BS model overprice the market value respectively. Next, there exist the linear relationships between the valuation errors and moneyness in TXO mostly. At last, in view of hedging errors, the other thing being equal, the shorter is the maturity, the smaller is the hedging error.

本文的实证发现，在评价误差方面，整体而言，隐含波动性模型对买权及卖权的评价误差最小，隐含波动性模型之理论价格低估了市场价格；而历史波动性模型、EGARCH（1，1）模型及平滑后的历史波动性模型之理论价格则大多高估了市场价格；接著，在评价误差与金融特性关系方面，各波动性模型之评价误差与价内价外程度、股价指数报酬率、股价指数波动性、距到期日及无风险利率等因素，大多具有显著的线性关系。

About the theory of the model errors, there are many theoretical problems to be solved, and many disscusional fields to be expanded and perfected.

但是测量平差中的模型误差的理论还有许多问题有待完善、扩展、深入，如函数模型可扩展到附有条件模型、概括函数模型、非线性模型；随机模型可扩展到相关、秩亏等情况；误差理论可扩展到线性近似误差。

Besides, the effects of light and temperature on stomata have not been modelled in any mechanistic model.

在第一章中，通过综述气孔对环境因子响应的数学模型的文献，发现目前对描述和模拟气孔行为的经验模型和机理模型是脱节的，可供选择的气孔模型还不能满足理论分析和实际应用的需要；经验模型没有机理的支持，不能用于理论分析，没有普适性；机理模型都过于复杂，而且其中的一些参数难以确定，所以它们还只能作定性模拟，不能作定量预测，另外，对于光强和温度的影响还未见有人模拟。

The theory and methods of ship's hydrodynamic pressure field are also studied, including halfrotator model and shallow-water inferior-critical model.

深入研究了水压场建模的理论和方法，包括回转体模型和浅水亚临界模型，用实测数据对回转体模型和浅水亚临界模型进行验模，为不同条件下选择水压场模型提供了一定的理论依据，并在实测数据的基础上对模型进行了修正。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失