查询词典 numerical method

The unique advantage of this halfanalytical numerical method is that the analytical process of Conformal Mapping can transform an irregular area into a regular one such as a rectangle. Therefore, the discretization error of numerical methods on the boundary can be avoided, and the numerical algorithm can be implemented more easily, with the computing efficiency improved.

这种保角变换的半解析数值方法的突出优点是：利用前期的保角变换解析处理将不规则的场域转化为规则的矩形域，从而避免了纯数值技术对复杂边界的离散化误差，降低了后期数值计算的算法复杂度，并提高了计算效率。

This paper studied a filtering high order numerical method for one dimension constant coefficient hy2 perbolic function. The stability and error analysis show the efficiency of this method. Numerical examples are also given to verify the analysis results.

摘 要 考虑一维常系数双曲型方程的高阶数值解法，引进了一种稳定性过滤算子FN ，最后从理论和数值实验上分析了该过滤算子对数值解稳定性和精度的影响。

After a series of study of numerical method related to impact dynamics, such as the transient finite element discretization method of conservation equations, numerical quadrature and hourglass control, the identification and redefinition of sliding interface and so on, the dissertation is aimed at to study a high efficient.

在分析八节点六面体单元出现沙漏变形的物理原因的基础上，通过引入抗沙漏节点力消除了因单点积分引起的各种沙漏模态。

A kind of delay parabolic partial differential equation is studied. A numerical method is proposed by discrete skill. The numerical stability for this kind of delay parabolic partial differential is analyzed by interpolation method.

研究了一类时滞的抛物型偏微分方程初边值问题，利用离散技巧，提出了一种数值方法，然后在一定插值技术下分析了算法的稳定性。

In order to study the numerical method to solve the viscous incompressible flow with free surface, the 3-D mathematical model for steady and unsteady hydrodynamic problem had been established and closed by k-εbuoyant turbulence model. The algebraic coordinate transformation method was used to fit the free surface, the Runge-Kutta method of three step and second precision was devised to simulate the time step. A high precision up-winding compact scheme was studied for the convection term, and the generalized conjugate residual method was set to solve the Poisson equation.

为了研究粘性不可压缩三维问题的数值求解方法，本文从基本的Navier-Stokes方程出发，采用代数拟合方法处理自由表面，用三级二阶Runge-Kutta方法对时间步进过程进行了模拟，并且对对流项的高精度迎风格式进行了研究，给出了求解压力Poisson方程的广义共轭剩余法，从而建立了能够模拟有自由表面的粘性不可压缩问题的定常、非定常三维水动力学模型，并采用k—ε浮湍流模型对其进行封闭。

In this paper, the space-time finite element theory and its application technologies are studied and discussed. Furthermore the space-time finite element method is used to analyze the transient characteristics of electromagnetism equipments. The work is important to develop the numerical method for the transient electromagnetic field. The detailed work is as follow.In the basis theory of finite element method used in the transient engineering problem, the functional theory and the finite element theory are applied to studied the existence condition of a generalized variation principle, which is the basis of the space-time finite element method.

本文在完善时空有限元法的基础理论和应用技术并将该方法应用于解决电磁装置的瞬态过程分析等相关方面进行了深入的研究与探讨，该工作对于发展瞬变电磁场问题的数值计算方法具有重要的意义，为此进行了如下几方面的工作：在工程瞬变问题的有限元方法的基础理论方面，本文应用泛函理论和有限元理论，系统讨论了一般工程瞬变问题的变分定理的存在条件及对应的变分定理。

Compared with the conventional model test method and empirical method it is found that the numerical method is more cost-effective and the method is worthy of being advertent and developed.

这一数值计算方法较之传统的实验和经验方法提高了计算分析效率、降低了成本，是一种值得重视和发展的数值计算方法。

A new mathematical model is put forward numerically to simulate the wheel ovalization.. In the numerical simulation, the dynamic model of a half railway vehicle coupled with a tangent track is employed. Using the new numerical method investigates vehicle-track coupling system dynamic responses including lateral and vertical displacement of wheelsets and the vehicle, lateral and vertical vibration acceleration of the track at different phase angle of the two side wheels of the same wheelset, which are compared with that of the traditional model. The numerical results show that the discipline and frequency of dynamic responses are accordant, amplitude and phase of lateral dynamic responses are different. It is concluded the traditional track geometric irregularity excitation model does not simulate the effect of periodic wheels ovalization on vehicle-track coupling system dynamic behavior truly, the new model is more accurate and reasonable.

本文研究了车轮二阶周期性非圆化—椭圆化，建立了一个新的模拟车轮椭圆化的数学模型，结合车辆－轨道空间耦合动力学模型，计算了同一轮对左右车轮不同相位和车轮椭圆度下轮对和车体的横、垂向位移，钢轨横、垂向振动加速度，并与传统模型计算结果作了对比，分析表明两种模型的动力响应变化规律和频率一致，但横向动力响应幅值和相位均存在不同程度不可忽略的差异，因此传统的轨道几何不平顺激励模型不能真实模拟车轮的周期性椭圆化对车辆－轨道耦合动态行为的影响，而本文模型更能反映实际椭圆车轮与钢轨接触情形，计算方法准确而合理。

Organization: Manufacturing Engineering Institute, Chongqing UniversityAbstract: Based on the influences of opposite clearance on computer numerical control machining, the CNC code precompensation method of the CNC machining opposite clearance is introduced, and the precompensation process of opposite clearance is also introduced. The vector operation rules are used to research the algorithm of precompensation, and the proposed algorithm has been applied in a special numerical control equipment.

摘 要：在分析反向间隙对计算机数控（computer numerical control，CNC）加工影响的基础上，提出一种数控加工反向间隙的数控代码预补偿法，给出了反向间隙预补偿流程，并采用向量运算规则进行了预补偿实现算法研究，所提算法已在某专用数控设备上得到应用。

For the four types of possible motions of caisson breakwaters, a dynamic analysis model of caisson breakwaters under breaking wave impact is founded and a numerical method is presented, which can be used to simulate the motions of caisson breakwaters. A small scale model test is designed, which can be used to examine the dynamic analysis model and numerical method.

本文对近破波作用下防波堤的动力响应进行了研究，针对防波堤的四种运动情况，建立了沉箱式防波堤的动力分析模型和数值模拟方法，并设计了一个模型实验，通过实验对所提出的理论模型和数值模拟方法进行了检验。

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。