数值的

In this paper, a three-dimensional multi-level hydrodynamic model with curvature correction in curvilinear coordinates has been developed based on the update turbulent theory and numerical method, which can effectively solve the practical problems of flows and water quality transportations in hydraulic engineering, and can strengthen the practical usage of the mathematical model.

本文基于现代紊流理论、现代数值计算方法建立适合描述水利工程中紊流规律的非线性数值模型，即曲线坐标系下的多层紊流水动力模型，旨在提高紊流精细模拟的实用性，以求有效地解决水利工程中的水流和输运现象的实际问题。

Numerical examples are studied to demonstrate the accuracy of the proposed method and to investigate the distribution of the optimal stiffness of the elastic restraints, the deformation of the elastic restraints and deflection of the stiffened plate for stiffened plate with different number of stiffeners, different cross section of stiffeners and different thickness of plate.

本研究利用牛顿法提出一个数值程序以求得使目标函数有最小值且满足拘束条件的弹性支承刚度，即求得最佳化的弹性支承刚度。本研究以数值例题探讨不同加劲板之最佳化的弹性支承刚度，弹性支承变形的分布及加劲板的最大挠度。

Mainly, we deriver time-accurate wavelet-based schemes for convection equation ,furthermore, we use it for numerical solution of convection equation and make a comparison with exact solution and solution derived from WGM.

主要的，对于对流方程，推导出了时间精度高的基于正交小波基的小波泰勒伽略金格式，进一步用这个格式计算了对流方程的数值解，并和WGM格式得到的数值解以及精确解作了比较，从而验证了格式的正确性。

Traditionally, the numerical simulation studies of gas-solid turbulence flow are based on Reynolds-Averaged models which are not able to get accurate results. While with the rapid development of computer science, direct numerical simulation method becomes more and more vital hotpoint.

传统的研究气固两相湍流数值模拟是基于平均的思想，其无法描述流动的精确结构等缺点让直接数值模拟的方法在这个方面随着高性能计算机的出现而飞速发展。

Based on these, a new numerical method for the Dirichlet problem is proposed in this thesis.

本学位论文，正是注意到了这些现象，提出了一种求解Dirichlet问题的新数值方法，克服了以往使用其它数值方法时常常遇到的困难和局限性，显示了分析数学中的问题借助概率理论来解决有着广阔的前景，在理论上和实际中都有着很好的意义。

Based on these, a new numerical method for the Dirichlet problem is proposed in this thesis. This method overcomes the difficulties and limitations resulting from others. It shows that solving problems in analysis by probability theory has a bright future both in theory and practice.

本学位论文，正是注意到了这些现象，提出了一种求解Dirichlet问题的新数值方法，克服了以往使用其它数值方法时常常遇到的困难和局限性，显示了分析数学中的问题借助概率理论来解决有着广阔的前景，在理论上和实际中都有着很好的意义。

Fourth precision solution can be derived from two grid sets solution with a second precision central difference scheme by Richardson extrapolation. It reduces the amount of calculation. Uncertainty is determined from the discretization error analysis. A finer grid calculation is made to validate the extrapolation scheme.

对于2阶精度中心差分格式的2套网格数值解，用Richardson外推法可以得到4阶精度的解，其工作量比直接求解4阶离散方程的工作量减少许多；对于计算中的数值不确定度，用该方法分析了离散误差，并用逐次加密网格的方法探讨了外推法的合理性。

Polynomial fitting was used to map out the pressure distribution curve of numerica...

与通过试验数据计算出的结果相比，数值模拟计算出来的轴向力相对误差在9%以内，而经验公式计算的轴向力相对误差为14%，采用数值模拟方法计算轴向力具有更高的精度，对多级离心泵轴向力平衡的研究具有指导意义。

The numerical study is carried out for a KVLCC2 tanker. Firstly, for the ship in oblique motion in deep water, determination of the computational domain, check of the grid dependence and selection of the turbulence model in numerical simulation are investigated. The effectivity of the numerical method is validated by comparing the numerical results with experimental data published in literature and the experimental results obtained by oblique towing test in the towing tank of Shanghai Jiao Tong University.

以KVLCC2大型油轮为研究对象，首先对船舶深水斜航运动粘性流计算中计算区域的确定、网格依赖性的检验以及湍流模型的选取等问题进行研究，通过将本文数值计算结果与他人的试验结果和在上海交通大学拖曳水池进行的船模斜拖试验结果相比较，验证了本文数值方法的有效性。

Here, the theory and the deducing process of the SEM based on the Legendre polynomial is given. The SEM can get a global diagonal mass matrix, which leads to a very simple explicit time difference scheme and high efficiency. Numerical simulation in the transversely isotropic medium are shown and the results approved that the SEM is a effective method for seismic wave modeling.

文中阐述了基于Legendre多项式的谱元法的理论和推导过程，该方法可以形成全局对角质量矩阵，在时间域使用显式的差分算法，提高运算效率，最后通过横向各向同性介质的数值计算，模拟结果表明该方法是一种有效的数值模拟方法。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。