数值算法

Numerical experiments show that the algorithm is robust to the attacks of the JPEG lossy compressing, cropping, superposing noise and resampling from the screen copy.

数值计算结果表明：该水印算法对JPEG有损压缩、剪切、噪声污染和重采样等攻击具有较强的鲁棒性。

Based on the 3D time-average Navier-Stokes equations, k-ε model was used to simulate the 3D turbulent flow field of whole flow passage in the Francis turbine including guide wickets, runner and draft tube. The energy performance and cavitation performance were predicted from the simulation results, and the calculated data were compared with the results of hydraulic turbine model experiment. The calculation of turbine efficiency and the measured efficiency was very closed and the maximal relative error was 0.9%.

该文基于Navier-Stokes方程和k-ε紊流模型，采用贴体坐标和交错网格系统，用SIMPLEC算法对一模型混流式水轮机引水元件、转轮和尾水管进行了联合计算与转轮单流道计算，数值模拟了水轮机各通流元件内部三维湍流流场，预测了水轮机的能量性能和空化性能，并与水轮机模型试验结果进行了对比。

Choosing the material model and the algorithm,three dimensional numerical simulation of anticartridge effect for certain aluminum alloy was realized and the parameter variation was demonstrated during the armor-piercing process.

通过选择合适的材料模型和算法，直观地演示了整个穿甲过程中各参量的变化，较好地实现了某型铝合金抗弹效应的三维数值模拟。

The research on parallel multi grid method has very wide potential application for large scale numerical computing problems.

多重网格算法的并行化研究对于大规模工程数值计算问题具有广泛的应用背景。

The pattern could be described as the fluids flow separated from the rearward edge of the strips; the fluids flow reattached to the cylinder surface behind the edge; the fluids flow reseparated from the cylinder surface downstream of the cross section of the cylinder.

为精细地描述台阶附近近壁特性，采用分区—耦合方法建立了适体正交曲线网格，采用低雷诺数的k-ε模型作为湍流模型，在非交错网格上建立起差分关系式，引用简化的SOLA算法对流场进行了数值模拟。

The power law scheme was used to calculate convective flux and diffusive flux,the over-relaxed correction approach was employed to calculate cross diffusion flux,and Rhie-Chow s momentum interpolation method along with SIMPLEC procedure was used to derive water level correction equation.

针对非结构网格下的潮流数值计算，采用有限体积法离散基本方程，对流-扩散项离散采用幂率格式，交叉扩散项引入超松弛校正方法，水位校正方程应用Rhie-Chow动量插值思想和SIMPLEC类算法导出。

The numerical algorithms, turbulence model and its application in calculation of twophase flow in the cyclone separator.

数值模拟算法、湍流模型及其在旋风分离器内部气固两相流动计算中的应用。2。

The numerical result shows that this method can correctly and quickly separate pure compress wave and pure shear wave from hybrid wave field with high precision, good boundary absorption, and the numerical process is stable, so it can be used to guide multi-wave multi-components seismic datum processing, and also point out that the method has difficulty to separate the coupled wave type such as surface wave.

数值模拟结果表明，该方法能够从混合波场中准确地分离出纯纵横波波场，且精度高，边界吸收效果好，计算速度快，计算过程稳定，可用于指导实际多波多分量地震资料处理，同时指出本文算法对相互耦合的波型无法实现准确分离。

With the technique of wavelets analysis and neural network intelligence, aiming at numerical calculation of temperature field in casting process of camshafts, the arithmetic of wavelet neural network is described.

利用小波分析和神经网络智能技术，针对凸轮轴铸造充型凝固过程的温度场数值求解问题，提出了小波神经网络算法。

Experimental results show that these measures greatly improve the efficiency of EAs.

数值试验证明，采用这些措施大大提高了进化算法的优化效率。

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。