查询词典 numerical function

Numerical tests shows that indicator function method is a simple and fast method, by which better reconstruction can be gained for no superior knowl-edge of the physical properties about media.

数值实验表明，指示函数方法简单快速而准确，能在不对介质的物理性质有先验的假设基础上，给出较好的重构效果。

We give a two-parameter penalty function and its exact penalty theorem for inequation constrain- ed optimization,meanwhile,We propose a quasi Newton algorithmfor solving the unconstrained nonlinear penalty problem and study its convergence,Numerical examples illustrate the feasibility of the algorithm.

对于含约束不等式的优化问题，构造双参数精确罚函数并给出精确罚定理，提出了一个求解这种罚函数问题的布鲁丹族拟牛顿算法，研究了算法的收敛性与收敛速度，并进行了数值试验，证明了可行性。

Two numerical methods using the integral function to do!

采用了两种数值方法做的积分函数！

The numerical results demonstrate that the MEI coefficients obtained using the technique,which takes dipole layer excitation as the "Metron" and the Green function in free space as the integral Kernel,are of higher precision over other techniques.

数值结果表明，利用电偶极子层激励作为测试子和自由空间格林函数作为积分核确定MEI系数的方法，比之其它方法具有更高的精度和明显的优点。

The research achievement are acquired as follows: 1From mathematical models for inverse scattering in two dimensional homogenous media including Dirichlet, Neumann, Robin,all kinds of probable mixed boundaries and cracks, direct and inverse scattering are discussed, and ill-posed integral equation and indicator function method are formulated for the diverse of boundary identification. It is shown that the kernel of the integral equation characters the boundary of scatterer, which is determined by solving it by virtual of regularity method, meanwhile, some numerical tests are given.

本研究取得了如下研究成果： 1）在二维均匀介质逆散射各种边界识别的数学模型（包括Dirichlet，Neumann，Robin，各种可能的混合边界问题，裂纹问题）下，分别考虑了正散射问题和逆散射问题，推导了上述各种边界识别的不适定积分方程以及指示函数方法，由于积分方程的核充分表征了散射物的边界，由此说明只要利用正则化方法求解该积分方程，就可以确定散射物的边界，并给出了一些数值实验。

For example, using the raised consine roll off function as the system pulse response, the feasiblity and effectiveness on the interpolation formula has been certified by theoretical and numerical analysis. The computer simulation result on 16-QAM signal is given.

以系统脉冲响应为升余弦滚降函数为例，利用理论分析和数值分析的方法验证了插值公式的可行性和有效性，并给出了16-QAM信号的计算机仿真结果。

Relative derivatives of such nodal interpolation function are also calculated by numerical approximation.

相对的导出节点内插函数也是经由数值近似计算。

The invention refers to a method to correct universal frequency of electric communication technique, its character: make signal index quantization on the complex number of cross product, to directly reflect the quantized numerical value of tangent value and the located quadrant of imaginary and real parts, use inverse tangent ROM table to discriminate the processed result, then make loop filter and phase accumulation on the discriminated result to obtain error-correcting angle, and use digital controlled oscillator to make table look-up and quadrant adjustment to obtain correcting factor; use the relationship of trigonometric function in each quadrant to compress inverse tangent look-up table ROM and digital controlled oscillator look-up table ROM.

一种涉及电通信技术的通用频率纠正的方法，其特征在于：它采用如下步骤：经过叉积的复数进行信号指数量化处理，通过该复数虚、实部信号的指数量化结果的差值及其极性直接反映虚、实部的正切值的量化数值以及所处象限，将处理后的结果通过反正切ROM表进行鉴频，鉴频后的结果经环路滤波和相位累加，得纠偏角度，通过数控振荡器针对纠偏角度进行查表和象限调整，得到纠正因子；通过个象限之间的三角函数关系来压缩反正切查表ROM和数控振荡器查表ROM的大小，本发明资源耗费小，效率高，可极大地节省内存资源。

By the principle of penalt function, the irrotational fluid field is constrained, and author has proposed the Difference Method for distinguishing fluid vortex modes among the natural modes of coupled systems. Author has calculated the real frequencies with the extra deductive method, and discussed the influence of the numerical solution due to the irrotational constraint.

对于流体有限扰动时的非线性耦合系统的有限元分析作了一些探讨，给出了非线性系统的基本方程、变分原理及有限元方程，并具体地导出了三维几何非线性流体单元的切线刚度公式，采用增量形式的Newmark预报——校正逐步积分法计算系统的动力响应，由Newton-Raphson迭代法及其修正方法求解系统的非线性方程组，还列出了不平衡力余量检查和位移迭代增量检查等迭代收敛判断准则。

The control principle of electrostatic shaping was introduced according to the balance between electrostatic force and resulting force formed by membrane deformation and the complex shaping process of SMEC. Then, taking the trisection circularity electrode for an example, the distribution characteristic of electric potential in the electrostatic field was analyzed, namely, the expression of potential function in the electrostatic field was deduced by Laplacian equation. And then, by combining the difference equation with electric potential expression, the numerical solutions of electrostatic force in single electrode mode and trisection circularity electrode mode were disposed. Finally, the calculated figure was compared with the ideal paraboloid and comparison shows that more accuracy would be achieved by multi-electrode control.

根据静电力与薄膜变形载荷作用力之间的平衡关系和静电拉伸薄膜反射镜成形的复杂过程，介绍了薄膜反射镜静电成形的控制原理；以三等分环状电极为例，分析了静电场中空间电势分布特性，即从拉普拉斯方程推导出静态场势函数的表达式；然后，利用差分与电势方程结合的方法，对单电极电场力和三等分环状电极电场力进行了数值求解；最后，将计算面形与理想抛物面进行了比较，结果显示，单电极情况下得到的薄膜反射镜面形不是理想抛物面，若采用多电极控制可获得更高的控制精度。

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。