查询词典 numerical computation

Along with the development of the computer industry, numerical calculation is widely used in the computation hydrodynamics.

随着计算机工业的飞速发展，数值计算方法在计算流体力学中得到了广泛的应用。

The physical property data vary from different numerical simulation applications. For example, in the simulating computation of hydromechanics, the physical quantities to be computed are pressure, density, temperature and velocity.

物理属性数据随着数值模拟应用的不同而不同，比如在计算流体力学模拟计算中，需要求解的物理量包括压力、密度、温度、速度等。

Numerical computation is to simulate on the atmospheric circulation of the Northern Hemisphere with this model under ideal boundary conditions.

从该模型出发可导出地球流体力学方程，用这一模型对理想边界条件下的北半球大气环流进行了数值计算。

A modified backward Euler method is developed which enables to increase considerably the accuracy of jump voltage computation as a result of freeing its computing from the influence of the faint asymmetrical initial current in such an inductive circuit as converter and completely eliminate numerical oscillation in converter simulation as often seen in the case of implicit trapezoidal integration method.

本文提出一种变形的后退欧拉法，用该法对换流器这样的纯电感电路进行跃变电压计算，可完全避免初始电流中微弱的不平衡对跃变电压计算的影响，大大提高了跃变电压的计算精度，并彻底消除了隐式梯形积公法用于换流器仿真时所存在的非原型数值振荡。

Firstly, Wavelet-Galerkin algorithm for solving the first kind of singular integral equation with the Hilbert kernel is proposed, we use the characteristic of periodic wavelet on L~2([0,1]) and Hilbert kernel to solve and make stiff matrix lower dimensions and become sparser through thresholding,thus the cost of computation is reduced. Because of the singularity of Hilbert kernel we use Tikhonov regularization method to solve the system of stiff equation. At last the convergence and numerical result of approximate solution are given. Secondly, an approach of regularization based on Fourier is presented for sideways heat equation; we give the theory proof and error estimate.

首先，提出了含Hilbert核的第一类奇异积分方程的小波伽辽金(Wavelet-Galerkin)数值算法，该算法中利用了L~2([0，1])上的周期小波和Hilbert核的特点进行处理，使得刚性矩阵维数降低并且通过阈值使得它更加稀疏，减少了计算量；由于Hilbert核的奇异性，通过Tikhonov正则化方法求解所得到的刚性方程组，给出了收敛性和数值结果；其次，对标准的一维逆热传导方程给出了一种基于Fourier正则化方法，给出了理论证明及其误差估计，解决了文献中算法与理论误差估计的不相匹配的现象，该正则化方法不仅保留了测量数据的部分高频成份，且与文献中的算法具有同样的计算量和误差估计。

The vector surface integral equation can't be applied to numerical computation directly because its integrands possess the high order singularity.

矢量的面积分方程因其被积函数具有高阶奇异性，不能直接应用於数值计算。

The action mechanism of the stun gun is analyzed in detail and the scheme design of the stun gun system is completed. With the SolidWorks software, three-dimensional model of the system has been constructed. The characteristics of the interior ballistics of the proposed scheme of stun gun are analyzed and the corresponding interior ballistics model is proposed. The numerical computation of the interior ballistics is also conducted. According to the functions of the electrical module ,the circuit is designed and the security and reliability of the system is analyzed. At last, the test scheme of the system is proposed and some experiments are carried out which validate the feasibility of the designed system.

论文中分析了电击枪的机理，完成了系统方案的设计；用SolidWorks软件建立了三维实体模型，分析了所提方案电击枪的内弹道的特点，建立相应的数学物理模型，并进行了内弹道分析计算；根据电子模块所要实现的功能设计了硬件电路；对设计的方案进行了安全性和可靠性的分析，最后拟定了试验的方案并进行了试验研究，验证了设计方案的可行性。

These constructional methods can be used to treat many problems, the numerical results show that the given interval extension has smaller excessive width relative to the range of the functions over a domain. For univariate differentiable functions, the definition of interval slope is extended from the first order to high order according to their differentiability, and iterative formula of high-order interval slope computation is also developed.

对多元函数，在不要求函数的可微性及有关Lipschitz常数的条件下，给出了分量函数区间展开的斜率算术运算规则；利用函数局部凸或凹的运算特点，通过递归计算建立了多元函数区间扩张的构造方法。

The basic principle of modern numerical computation is to preserve the intrinsical character of the original problems.

现代数值计算的基本原则是尽可能保持原问题的本质特征。

It applied Kirchhoff expression to FDTD numerical computation of acoustic scattering problems,and iterated near field on the integral surface to far field that was contributed to,which could b.

针对此问题，提出一种新的外推方法，它将柯西霍夫公式应用于FDTD数值计算中，将积分面上每一步的近场都叠加到它有贡献的远场时刻上去，近远场变换可以与FDTD的场分量迭代同步进行，不需要将外推边界上每一时间步的场值都存储下来，减少了存储空间。

There are different types of personal loans available.

有许多不同类型的个人贷款优惠。

The above mentioned teaching model of spiral rising can be used to avoid rigidness in teaching.

上述螺旋式上升的教学模式，可以避免教学形成模式後的僵化现象。