逼近度

In this paper the degree of approximation by n-dimensional Bernstein polynomials is discussed.

本文讨论了k维空间的伯恩斯坦多项式在不同的距离下的逼近度。

A series of Gaussian digital approximation filters used in roundness measurement were designed on the basis of approximation method and bilinear transformation.

文中用逼近法和双线性变换法，设计了用于圆度测量的高斯数字逼近滤波器，并给出了零相移的递归滤波算法，计算量小，计算效率高，易于实现。

In the fourth chapter, firstly it introduces the Boolean functions algebraic expressions of the 2-value clock-controlled stop-and-go generator and Gunther generator. It reveals the balanced property of the two kinds of Boolean functions, and studies the Walsh cycle spectrum and the autocorrelation function. It also obtains the coincidence rate of their output sequences with affine sum of some bits of input sequences, and analyzes their ability of resisting the best affine approximation cryptanalysis and differential cryptanalysis. Secondly, we properly present a new definition of the Best Affine Approximation, namely BAA on the Boolean vector functions, followed by the spectral characteristic of such defined BAA attacks through using the decomposition formula of the union distribution for random variables. A lower bound of such BAA attacks is proposed. Finally, we also study the spectral characteristic of the second kind of nonlinearity of Boolean vector functions, followed by a higher bound of such nonlinearity. Furthermore, the limited relationship between the second kind of nonlinearity of Boolean vector functions and the linear structure of the linear combination of every component is analyzed.

在第四章中，首先给出了2值密钥流"停走生成器"和"衮特生成器"中实际存在的布尔函数的代数表示，揭示了这两类布尔函数的平衡性，随后研究了它们的Walsh循环谱和自相关函数等，得到了它们的输出序列与输入序列中的某些bit的仿射项的符合率，分析了它们抵抗最佳仿射逼近攻击和差分攻击的能力；其次，我们合理地给出了布尔向量函数最佳仿射逼近的新定义，利用布尔随机变量联合分布的分解式考察了相应的谱特征，并给出了布尔向量函数与其最佳仿射逼近的符合率的一个下界；最后，我们还考察了布尔向量函数第二类非线性度的谱特征，给出了布尔向量函数第二类非线性度的一个上界，并揭示了布尔向量函数第二类非线性度与其各个分量的线性和的线性结构之间存在的制约关系。

A new network evaluation criterion, the degree of approximation, was employed.

采用逼近度作为网络新的评价标准。

Firstly, the optimum network was determined on the degree of approximation, which made the network avoid over fitting. It was shown that the single component and multi-component pollutions were identified and quantified successfully.

首先，采用模拟的光谱数据，引入逼近度的概念确定最优网络模型，避免了网络陷入局部极小，成功地实现了单组分和多组分污染物的同时鉴别和定量分析。

Two-dimensional Bernstein type operators on simplex are constructed, and a necessary and sufficient condition of uniform approximation by mem is obtained, at the same time, the degree of approximation is characterized by two-order moduli of smoothness.

并且构造出单纯形上推广的二元Bernstein型算子，给出其一致收敛的一个充要条件，同时用二阶连续模刻划了它们的逼近度性质。

This paper presents an improved variable stepsize BP learning algorithm by making use of the concept of model approximation degree and by taking advantages of the merits of simulated annealing method.

基于模型逼近度和接受概率的一个变步长快速BP学习算法叶东毅（福州大学计算机科学系福州350002）摘要本文给出模型逼近度的概念。

The second part has summarized from the one-dimension and multivariate respects the abundant approximation properties of Bernstein polynomials, mainly including the estimation of approximation degree, derivative approximation, linear combination approximation and weighted approximation.

第二部分从一元和多元两个方面系统总结了Bernstein算子丰富的逼近性质，主要包括逼近度估计、导数逼近、线性组合逼近和加权逼近等。

The thesis first recommends the famous fuzzy Gaussian approximation system which is based on the Gaussian membership function, the fuzzy logic of product reasoning and the fuzzy law of weight approach. This thesis is discusses the general fuzzy Gaussian membership function that can approximate the form of triangular, trapezoid and Gaussian function , and its basic form is .The general fuzzy Gaussian membership function is to be generally used in the field of approximation .

模糊逼近是近年来发展比较迅速的一个新兴方向，论文首先给出了模糊理论中著名的基于高斯隶属函数、乘积推理模糊逻辑和重心解模糊法的模糊高斯型万能逼近定理，在此基础上本文进一步给出了可以用来逼近三角形、梯形和高斯形的广义高斯隶属度函数形式，它的基本形式是。

With this approach,the selection of weights and the estimation of approximation order simply depend on a parameter w.

该法适用于任意次数的有理Bezier曲线/面、任意的控制多边形/网格，权因子的选择和逼近度的估计都只依赖于一个参数w。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了