数值分析

Numerical dispersion characteristic and impedance relationship of three dimensional perfectly matched layers are analyzed under finite difference approximation in this paper, respectively, which show that numerical dispersion relationship of PML is different from that of the FDTD equations and the impedance of homogeneous PML medium is the same as that of free space.

本文分别分析了有限差分近似下三维理想匹配层的数值色散特性和阻抗关系，分析表明，理想匹配层的数值色散关系有别于时域有限差分方程的数值色散关系；有限差分近似下，均匀理想匹配层媒质的阻抗和自由空间的阻抗相同。

Gradual regression analysis through specific mathematical algorithms to achieve automatic data selection and remove useless or even wrong data; The test data analysis revealed: the furfuran content have a very good correlation with polymerization degree of insulation paper, and a correlation model between furfuran content and DP was founded by regression analysis.

逐步回归分析通过偏回归平方和及显著性分析，实现对试验数据的自动分析、筛选，排除无用甚至是错误的数据；本文试验数据逐步分析结果表明：油中糠醛含量对数值与绝缘聚合度相关性最好，与现场实际分析结果一致；通过回归分析建立了绝缘聚合度与糠醛含量对数值的关系模型。

That is to utilize general MPI programming environment, program on the NHBL parallel computational model, analyze and predicate the running cost of program by using the cost function of this model, and analyze the scalability of program by using the time-scale scalability metric. Finally, we analyze the numeric algorithm example---matrix multiplication and the nonnumeric algorithm example---PSRS sorting on Dawning-1000 MPP and NHPCC-cluster NOW system by using the integrative method.

提出了将并行计算模型、算法、编程进行一体化的研究的方法，即利用通用的标准的MPI编程环境，将编程建立在NHBL并行计算模型上，并且利用该并行计算模型的评价函数进行分析、预测程序的运行代价，再利用时间比例的可扩放性分析方法来分析程序的可扩放性性能；最后我们用PSRS排序算法和矩阵乘法这两个典型的数值和非数值的算法，在曙光-1000并行机和NHPCC-Cluster工作站集群上进行了一体化的分析。

In this topic, the dynamic analysis methods for piezoelectric vibrator are studied systematically based on the theoretical model, FEM numerical experimentation and FEM governing equation for given compound-mode vibrator, and some valuable conclusions are obtained. The main work accomplished is summarized as follows: 1.Elaborate the main modeling methods for piezoelectric vibrator and the significance and necessity to study the dynamic characteristics of piezoelectric vibrator which emphasize the urgency of this paper. 2.Take the bending deformation induced by piezoelectric ceramic as example, the energy transfer mechanism of electric energy to mechanical energy are analyzed; the motion and force transfer mechanism are analyzed for the longitudinal-bending vibrator. 3.Based on mode assumption and Hamilton principle, the coupling model of piezoelectric vibrator of linear USM is built; moreover, the equivalent circuit model is obtained and a coupling equation represents the relation between electric parameters and mechanical parameters is derived which provides foundation to match the vibrator and driving circuit. 4.Combine the constitutive equation of piezoelectric ceramic with elastic-dynamical equation, geometric equation in force field and the Maxwell equation in electric field and the corresponding boundary condition equation, the FEM control equation for piezoelectric vibrator of USM to solve dynamic electro-mechanical coupling field is established by employing the principle of virtual displacement. The equation lays the foundation to study the non-linear constitutive equation of piezoelectric ceramic driven by high-power. 5.Define the dynamic indexes of characteristic of vibrator and carry out variable parameters simulation by calculating the model parameters and the electric characteristics of vibrator are simulated according to the equivalent circuit model. By numerical experimentation, the working mode of vibration of vibrator and the shock excitation results of the working frequency band which provides the mode frequency to realize bimodal are analyzed. Detailed calculation of the electro-mechanical coupling field parameters is made by programming the FEM control equation.

本课题从理论模型、有限元数值试验、有限元控制模型等方面以复合振动模式振子为例对超声电机压电振子的动力学特性及其分析方法进行了全面系统地研究，得出了许多有价值的结论，主要概括如下： 1、阐述了目前针对超声电机压电振子的主要建模方法，对压电振子动态特性的研究意义和必要性进行了论述，突出了本文研究内容的迫切性； 2、以压电陶瓷诱发弹性体发生弯曲变形为例，分析了压电陶瓷通过诱发应变来实现机电能量转换的机理；对基于纵弯模式的压电振子的运动及动力传递机理进行了分析； 3、基于模态假定，利用分析动力学的Hamilton原理，建立了面向直线超声电机压电振子的机电耦合动力学模型，并据此建立了压电振子的等效电路模型，导出了电参量与动力学特性参量的耦合方程，为压电振子与驱动电路的匹配提供了依据； 4、从压电陶瓷的本构方程出发，综合力场的弹性动力学方程、几何方程、电场的麦克斯韦方程以及相应的边界条件方程，采用虚位移原理，建立了压电振子动态问题机电耦合场求解的有限元控制方程，为研究其大功率驱动下的非线性本构模型奠定了基础； 5、界定压电振子的动力学特性指标，对压电振子的机电耦合动力学模型参数进行计算及变参数仿真；依据等效电路模型，对压电振子的电学特性进行了仿真分析；通过有限元数值实验，对压电振子工作模态附近的模态振型及工作频率附近的频段进行了激振效果分析，找出了实现模态简并的激振频率；利用有限元控制方程，通过编程计算，对压电振子的力电耦合场参数进行了详细计算，得出了一些有价值的结论。

In this thesis, the methods for solving eigenvalue problems and conventional reanalysis methods are studied firstly. Then, a new reanalysis method for real modal reanalysis of structures subjected to topological modification with added degrees of freedom is presented. This method is composed of the single step perturbation method and the Rayleigh-quotient iteration. The numerical examples show that this reanalysis method is very effective and high-quality.

本文首先在对常规的特征值数值求解方法和重分析方法研究的基础上，针对实模态的自由度增加的结构拓扑修改重分析，提出了一种新方法，该方法由于结合了单步摄动法和瑞利商逆迭代法两者的优点，应当是一种比较理想的重分析方法，算例的数值结果也有力的验证了该方法确实是一种高精度、十分有效的实模态重分析方法。

The color component of ir was the best for close operation while the other two color component (r+g and r+g+ir) would do a better performance on open operation. Finally, the results of these 3 color components for recognizing weed showed that ir was the best. So, as a conclusion, the color component of ir is best for recognizing weed based on computer vision. Also the operation process for recognizing weed was proposed.6. Supposed an idea on the variable spray mechanism of weedicide.

借助Matlab7.0.1软件对数值量ir和数值组合r+g、r+g+ir进行进一步的分析，在对ir、r+g、r+g+ir图像完成为了去除图像噪声而进行的中值滤波和二值化背景分割后，为消除特定图像细节进行二值形态学操作，通过分别对三个数值量和数值组合的开启和闭合操作结果的比较，发现处理后的数值量ir适合进行闭合操

Analyzing the process in the paper, the hydromechanics model of the hydromechanical deep drawing is built up, and the method on the numerical simulation of the hydromechanical deep drawing is put forward, which is an effective approach to the numerical simulation.

本文通过对筒形件充液拉深工艺的分析，建立了接近实际的充液拉深流体力学模型。结合有限元数值模拟技术，提出了充液拉深流体压力行为在数值模拟分析中的实现方法，为充液拉深有限元数值模拟提供有效途径。

The method of CFD numerical simulation is employed to replace experimental investigation. Hence, STAR-CD of the commercial software is used to simulate the outer flow field and heat transfer performance of integrated heat sink with heat pipes cooled by airflow. It is found that simulated results agree with experimental results well, which indicates that simulation method is reasonable and reliable. Further, simulated computations for different fin thickness, fin pitches and air velocities are performed to analyze their effects on heat transfer performance of heat sink. Finally, a new optimized structure of integrated heat sink with heat pipes is provided to meet future demands for cooling CPU and its heat transfer is also evaluated. For multi-heat source and higher dissipation power of electronic devices, the integrated heat sink with heat pipes attatched fins stagged in different positions of channels is presented and its flow and temperature fields are also simulated to enhance heat transfer. As a conclusion, all mentioned above are useful for the design of heat sink with excellent efficiency of heat dissipation and further research.

应用商业软件Star-CD对CPU集成热管散热器的外部流场和传热特性进行了数值模拟，将数值模拟结果和试验结果对比，验证了所提出的数值计算方法是可靠和可行的；利用此数值模拟方法对CPU集成热管散热器在不同散热翅片间距、厚度和气流速度下散热器的流动与传热性能进行了数值计算，分析了这些参数的变化对散热器传热性能的影响；针对未来CPU冷却的要求，确定了与最优气体流速匹配的最佳翅片间距、厚度的CPU集成热管散热器的新结构；利用试验评测了根据数值模拟提供的新结构开发出的新CPU集成热管散热器的传热性能；最后在场协同强化传热的理论的基础上，对CPU集成热管散热器的散热翅片错位排列来强化散热器的散热，满足未来大功率、多热源的电子元件的散热，为今后进一步优化散热器提供了依据。

In the couping solution, based on the characteristics of the models in this dissertation, each of loading step is finished in unit time. Thus the volumetric strains on the current increment step as analysis parameters are inserted into the equation of continuity and a physical equation for pore water pressure is presented. The fundamental solutions of two kinds of classic problems (axial symmetry and plane strain) are derived. By use of the fundamental solutions of pore water pressure combined with finite element method of soil mechanics, a semi-analytical and semi-numerical method for nonlinear consolidation equations is presented.

在耦合分析中，根据本文模型的特点，将每一荷载增量步看作单位时间完成，对应当前增量步的体变分量作为分析参数代入连续方程，建立了基于数值模型的孔压变化方程，根据工程中最常见的两类问题推导出基本解，结合土骨架的控制方程建立了此类液-固耦合问题的半解析半数值解答体系，编制了有限元程序，从而实现了从建立本构关系到模拟固结问题的全数值方法。

The system has some advanced functions such as searching multiform NWF product,the change of west wind index on 500 hPa,the physical feature table of every station,the error and comparison of forecast capability of NWF,searching fax picture,and showing 3D picture,etc.

而对数值预报的释用又是整个业务数值天气预报系统的一个关键的组成部分。就大多数数值预报产品本身而言，虽然目前已经具有较高的质量，但由于分析误差和模式自身的误差，对局部地区的天气形势不可能预报得非常准确，因此我们不可能将任何数值预报产品直接用于天气预报，而通过发展数值产品的释用技术来制作气象要素预报是可行的。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。