数值分析

The results of field test indicate that the earth pressure of abutment,different from lin...

有限元分析结果表明，台背土压力分布存在一定的空间效应，在同一深度上数值并不相等，中间大，两侧小。用库仑公式计算的结果比数值计算与实测的结果偏于安全。

Finally, the idea of using new numerical method such as Discontinuous Deformation Analysis and Numerical Manifold Method to simulate the joint of CFRD is proposed, which can make guidance on the design and calculation of CFRD built on thick alluvium deposits.

提出引进新的数值方法，如不连续变形分析方法和数值流形方法，来模拟和计算面板坝接缝变形的设想，对深覆盖层上面板堆石坝的设计和计算有指导意义。

Chapter 9: We report a large quantity of numerical experiments of 13 different algebraic multigrid algorithms for solving the Poisson equation, anisotropic equation, equation with cross-derivative terms, general matrix problems with large off-diagonal positive entries, biharmonic equation, Toeplity matrix, elasticity systems, finite element discretization of the Laplacian and even 3D problems. Particular attention is focused on asymptotic convergence factors and CPU-time consumed. Numerical results for many different types of practical problems demonstrate the efficiency and robustness of the proposed algebraic multigrid methods.

第九章：在各种代数多重网格算法的基础上，进行了大量的数值试验，具体给出了十三种不同的代数多重网格方法求解泊松方程，各向异性方程，带混合导数项的方程，带有大的非对角正元素的一般矩阵问题，重调和方程，托普利兹矩阵，弹性力学方程组，拉普拉斯算子的有限元离散，甚至三维问题的较为丰富的数值结果，重点关注它们的渐近收敛因子和所需的CPU时间，来源于不同类型问题的计算结果既为代数多重网格理论分析和算法的改进提供了很实用的资料，同时也证实了本文给出的代数多重网格算法的效绩和稳健性。

In this paper, a procedure of nonlinear analysis of the cable-stayed bridge was developed based on the nonlinear theory of structures using the finite element method, in which the vehicle-bridge interaction element based on the concept of dynamic condensation is used. The influence of vehicles on the response of the cable-stayed bridge is studied by employing the spung mass model and the bridge model with and without considering cable vibration modes.

本文拟应用非线性力学分析程序与有限元素数值计算法，建立斜张桥的非线性分析程序，应用VBI的车桥互制元素配合动态浓缩的观念，以悬浮移动质量模拟车体对斜张桥的影响，并对考虑与不考虑缆索振动模态两种分析模型，做一对应分析比较。

With the support of a major research grant of Zhejiang Province (No. 001101027) and the Plan of Promoting Education of Excellence of Zhejiang University in the 21st Century, this dissertation is devoted to address the above problems and fabricate an L-band EDFA with low cost, high performance and technological innovation.First the mechanism of an erbium doped fiber amplifier is introduced. Various theoretical models based on classical rate propagation equations are summarized and compared for their applications. We use a modified numerical model based on the Giles model, which agrees with the experimental results well. This serves as the theoretical base for the whole thesis and will be used to optimize the characteristics of EDFAs. A novel method based on a map of noise figure and gain is proposed to analyze efficiently the dependence of the noise figure and gain for EDFAs on the EDF length and the pump power. The characteristics of various EDFAs are studied and compared.Secondly, some important parameters are introduced to describe the characteristics of EDFAs. The methods and the experimental setups for measuring the gain and noise figure of an EDFA are emphasized. We introduce how to measure the characteristics of each component of an EDFA, especially the gain and absorption coefficient of an erbium doped fiber.Thirdly, four types of simple and novel L-band EDFA structures with low noise, high gain and low gain ripple are proposed to satisfy the requirement of a DWDM system. They can be classified into two categories. In the first category, a single ASE pumping is served asa secondary pump. This category includes the following three types. Type: a new construction using a fiber Bragg grating in an unpumped EDF section at the input side. Type: a new structure of L-Band EDFA with two-stage pumps, which utilizes the forward ASE as a second pump.

本论文本着科技创新、服务于生产实践的精神，以设计价格低廉，性能优越、结构合理简单的L-band EDFA为目标，依托浙江省科技厅重大科学基金资助项目(001101027)和浙江大学振兴教育计划资助的全光网络的搭建—《光通信技术》课程实验建设项目，展开了如下工作：首先，介绍了掺铒光纤放大器的工作原理，归纳总结了基于速率方程基础的EDFA的各种理论模型，分析比较了各个模型的特点和适用场合，最终选择完善的Giles理论模型作为本论文分析设计EDFA的理论基础；针对实际实验条件提出了修正的EDFA模型的数值计算方法；创新地提出了增益—噪声系数全局分析法，直观有效地分析了EDFA的增益和噪声系数与掺铒光纤长度和泵浦功率的依赖关系，并对各种EDFA的性能作了全面的比较；第二，介绍了掺铒光纤放大器特性参数的定义与测量方法，重点介绍了噪声系数和增益系数的测量方法及实验装置；介绍了组成掺铒光纤放大器各组件的特性测量方法，重点介绍了测量掺铒光纤参数的方法和实验装置；第三，针对WDM系统对L-band EDFA谱平坦、低噪声、高增益的要求，我们创新地提出了四种不同的L-band EDFA结构，按设计思路可以分为两大类：一类是基于单抽运二级泵浦法，这一类包括在未泵浦掺铒光纤的输入端插入一根布拉格光纤光栅的两段L-band的EDFA的新结构；基于前向ASE光作为二级泵浦源推动下一级EDF工作的泵浦分配、两段级联L-band的EDFA的新结构；基于单根光纤光栅、泵浦分配、两段级联的EDFA；另一类则是基于同时应用前后向C-band ASE作二级泵浦源的双抽运法，如基于前后向ASE光作为二级泵浦源的三段级联L-band的EDFA的新结构。

According to the energy conservation theory, BOM and CSIM4 were coupled. The BOM has no treatment on transmission solar radiation, which is of great importance when the model is adapted to Arctic Ocean. So the treatment was introduced to BOM. Through numerical test on different lead albedos, it was found that sea ice thickness is not so sensitive to lead albedo, which may be contribute to the lead occupies little ratio within multiyear sea ice pack. The reason of summer over-melt of arctic sea ice is the NCEP reanalysis downward solar radiation being larger than its reality. Then the arctic sea ice climate variability was simulated. Results showed that: simulated ice thickness change is in accord with the submarine investigated mean sea-ice draft changes. Simulated annually maximum ice thickness along the Eurasian continental oceans are closely related to the observed ones. The long-term mean simulated ice motion has the same features of the SSM/I derived ice motion. Sea ice extents in differential sub-regions have same trends comparing to the satellite passive-microwave data derived ones. Simulated ice concentration is closely related to the observed in the Arctic sub-regions. Sea ice flux through the Fram Strait involves ice concentration, motion and thickness. It is a composite criterion for sea ice model evaluation. The simulated ice area and volume export through the strait accord with the satellite derived or statistically reconstructed ones.(5) The simulated ice thickness climate variability and mean sea surface current of the coupled model were analyzed, results showed: the total ice volume in the Arctic Ocean has a significant decreasing trend. The volume variability is of a 10-year timescale oscillation, with two major periods of 12-13a and 18-20a. Mean ice thickness in the arctic sub-seas has different tendencies. It has an increasing trend in the Barents-Kara Sea and Baffin Bay-Labrador Sea, and decreasing in the others. The characteristic time scale of 7-10a wherein the river discharges leads the Fram Strait ice volume export is about the period that river water takes to be conveyed across the Arctic Ocean.(6) Using the simulated ice distribution in the Arctic Ocean and China precipitation, air temperature and SST in tropical key regions, the climate teleconnection were studied. Result showed: When the mean sea ice thickness is large in the central Arctic Ocean and Chukchi-Beaufort Sea , and small in the Barents-Kara Sea and Baffin Bay-Labrador Sea , the precipitation in South China, Tibetan Plateau, and the north part of Northeastern China are always smaller than normal, and v. v. When the mean ice thickness is small in CA, BC, East Siberian Sea and Greenland-Iceland-Norwegian Sea , and large in BL, The air temperature in north-eastern China, the southern of Tibetan Plateau, and Hainan Island, are always lower than normal, and v. v. In addition, when the sea ice is thick in BC and BL, the SST is larger in the middle and eastern Pacific Ocean, and is smaller in the tropical Southeastern Indian Ocean.

由于BOM没有考虑透射太阳辐射的物理过程，研究表明透射太阳辐射对北冰洋的能量收支起到重要作用，因此在BOM模式中引入了对透射太阳辐射的处理；通过对不同水道反照率的数值试验表明海冰厚度对水道反照率的敏感性不强，可能与海冰区水道面积占的比率很小有关；而模式模拟的北极海冰夏季&过度融化&主要源于NCEP再分析资料提供了偏大的太阳短波辐射；对北极海冰的气候变率进行了模拟研究，结果表明：模拟的海冰厚度变化与潜艇探测的海冰吃深度变化具有一致性；模拟和观测的亚欧大陆沿海的年内最大海冰厚度有很好的相关；模拟的海冰移速与长期平均的卫星反演的海冰移速具有相同的速度分布特征；模拟的各个海区海冰面积的变化趋势与卫星反演资料分析的结果基本一致；模拟与观测的主要海洋分区的海冰密集度具有很好的相关：弗瑞姆海峡的海冰体积和面积的输送涉及到海冰密集度、厚度和移动速度，是判断模式模拟能力的一个综合的指标，模式模拟的结果与卫星反演或重建的面积输送、体积输送具有很好的一致性；(5)分析了模拟的北极海冰厚度的气候变率及气候平均表层海流场，结果表明：北极海冰的总体积有显著减少的趋势，北极海冰总体积的变化具有10a际尺度振荡的特点，存在18-20a和12-13a两个主周期；北极海冰的平均厚度在各个海区的变化趋势不同，在巴伦支—喀拉海和巴芬湾—拉布拉多海地区海冰厚度有显著的增加趋势，而其它海区存在减少的趋势；通过对模拟的气候平均表层海流的分析表明，北极河流流量超前弗瑞姆海峡海冰流量7-10年的特征时间尺度与表层海流的气候分布存在着必然联系：(6)利用模拟结果以及中国降水、气温和热带关键区SST资料，讨论了北极各海区海冰平均厚度与中国降水、气温以及热带关键区SST的关系，结果表明：在北极中心海区和楚科奇—波弗特海海冰厚度偏大，在巴伦支—喀拉海以及巴芬湾—拉布拉多海海冰厚度偏小，则中国降水在华南地区、青藏高原和东北北部降水偏少，反之相反；在北极中心海区、东西伯利亚海、楚科奇—波弗特海以及格陵兰海海冰厚度偏小，在巴芬湾—拉布拉多海海冰厚度偏大，则在中国东北地区、高原南部地区和海南岛附近气温偏低，反之相反；另外，北极楚科奇—波弗特海和巴芬湾—拉布拉多海海冰厚度偏大时，在热带中东太平洋海温偏高，而在热带东南印度洋海温偏低。

D depth-averaged model for flows in river with submerged groins;2. Simulation study of organ pipe nozzle submerged water jet;3. The submerged tunnel is simulated by the Elastic-Plastic FEM to analyse its influence on the environment.

为了分析淹没坑道对环境的影响，采用弹塑性有限元法对被淹没的坑道进行了数值计算，分析了不同情况坑道衬砌及围岩的破坏变形情况，同时提出了相应的加固方案，并对拟采用的不同方案加固效果进行了模拟分析，分析结果表明所提出的加固方案可行。

The method of finite element discrete and optimal parameter back analysis is adopted.(3) Concentrated on the question of high external water pressure of the deep-lying tunnel, the basic theory and method calculating external water pressure are systematically studied.(4) Based on Jinping cascade 2 hydropower station, numerical simulation rain infiltration of seepage field under different drainage pattern and grouting pattern are studied, also, the high external water pressure is analyzed and studied and some seepage control measures are put forward.

2采用有限元离散—优化法进行参数的反演分析；(3)针对深埋隧洞的高外水压力问题，进一步分析和研究了衬砌水荷载及外水压力的作用机理和计算方法；(4)以锦屏二级水电站深埋长引水隧洞作为本文的主要研究对象，采用考虑降雨入渗渗流场分析的方法对排水方案和灌浆封堵方案不同情况下的渗流场的水头分布进行了数值模拟，并对其外水压力进行了分析和研究，提出了渗流控制的具体措施。

According to the analysis and simulation of this process, some suggestions are raised which are helpful to improve Meiyu front forecast ability in real time operation, such as using some new remote sensing data and the time and space densified data, strengthening the analysis of the mesoscale numerical model products, through the man-machine interaction to analyze more diagnostics and the air mass features based on different vertical coordinate systems.

6根据对本次梅雨锋的分析和模拟结果，提出了在目前实时预报业务中改进对梅雨锋暴雨预报能力的一些建议。包括对新的遥感资料和加密资料的使用、加强对中尺度数值模式资料的分析、通过人机交互方式分析更多的诊断量和利用不同垂直坐标系统分析气团特征等。

Finally, stochastic vibration analysis of a two-floor frame structure by blasting seismic action is done by finite element program ANSYS. In order to contrast, that by nature seismic action is also done here, and displacement field, velocity field and stress field of this two kind of condition are obtained, and differences of the structure damage mechanics by two kind of action are analyzed. Dynamic reliability analysis of the two-floor frame structure is done using of simulation results, obtaining the safe reliability level of the structure by seismic action, and seismic safety evaluation of the frame is completed.

最后，运用有限元程序ANSYS对爆破地震动作用下一个两层框架结构进行了随机振动分析，为了进行对比，这里也对结构受天然地震动作用进行了随机振动分析，得到了两种地震动作用下结构响应的位移场、速度场和应力场的变化情况，分析了爆破地震动和天然地震动对建筑结构物破坏机理的不同；应用数值模拟的结果对该两层框架结构进行了动力可靠性分析，得到了其在地震动作用下的安全可靠度，完成对该框架的爆破地震安全性评估。

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。