逼近的

The characteristic approximation is used to handle the convection part along the direc-tion of fluid namely characteristic direction to ensure the high stability of the method in approximating the sharp fronts and reduce the numerical diffusion; The mixed finite element spatial approximation is employed to deal with diffusion part and approximate the scalar unknown and the adjoint vector function optimally and simultaneously; In order to preserve the integral conservation of the method, we introduce the modified characteristic method.

该方法对方程的对流部分沿流体流动的方向即特征方向离散以保证格式在流动的锋线前沿逼近的高稳定性，消除数值弥散现象；对方程的扩散部分采用最低次混合有限元方法离散、同时以高精度逼近未知函数及未知函数的梯度；为保证方法的整体守恒性，在格式中引入修正项。

BP neural network function approximation of the source!

BP神经网络函数逼近的源程序！

In elliptic case,the compactness of"convex polyhedrons"is destinedto be true because of the"local Lipschitz continuity of convex functions",whilein parabolic case,we cannot expect convex-monotone functions have such goodproperties as convex functions.

在广义解存在性的证明中，参考椭圆情形由"凸多面体"逼近的思想，我们采用了由一种特殊构造的"凸单调多面体"逼近的途径，但在证明这种凸单调多面体族的紧性时，我们遇到了困难。

The stopband error of prototype filter is used to be the objective function for optimization. Instead of the method of least square approximation, this paper introduce the method of best uniformity approximation.

选择低通原型滤波器最大阻带衰减为优化的目标函数，通常的优化目标函数选用最小平方逼近的方法，本文提出了使用最佳一致逼近的方法。

The method of calculating the perturbed Chebyshev-Padé approximation is proposed for not only the general situation but also some special cases, i.e., an odd function and an even one.

提出了一种新的带有扰动的Chebyshev-Padé逼近，它依赖于一个扰动参数，其优点在于：它可以通过调整扰动参数来提高逼近的精度。

In this paper we investigate the researching state, the developing situation and the prospect for the summability , the strong summability and their relevant approximating oder , strong approximating oder of Cesdro mean - an important linear summation process of the Fourier - Laplace series of functions on sphere.

本文研究了球面上的函数用其Fourier—Laplace级数的一种重要的线性求和法-Cesaro平均来求和与强求和及其相应的逼近与强逼近的阶的研究状况、发展态势和前景展望等。

Structure-Based Approximation Learning Theory: Under the description of manifold and topological architecture of neural field, we have proposed a learning frameworks of neural networks based on global architecture approximation theory borrowed from the concept of topology and manifold to solve the optimal problems of learning in non-nonlinear and non-Euclidean space, and discussed a few basic components of the learning theory, learning mechanism and learning algorithm in the term of structure-based approximation and global structure analysis.

基于结构的逼近学习理论：通过人工神经网络模型神经场的流形结构和拓扑结构描述，我们提出了在非线性和非欧氏空间中基于整体结构逼近的神经场学习理论框架；用对偶流形理论和拓扑概念作为工具，讨论了神经网络的学习理论、学习机理、学习算法和算法的具体实现。

And we used them into the inspection of these polluted gases. We used them because the constringent speed of wavelet neural network is very fast, they are not sensitive to the inputs of the network and they have the characteristic that they also can effectively approach the functions or signals. Classical neural networks mostly train the network with back propagation algorithm.

在目前常用的一维小波神经网络的基础上，我们研究了用来处理多维数据信息的小波神经网络，并将其应用于室内混合气体检测，主要是基于小波神经网络学习收敛速度较快，对网络输入不是很敏感，以及小波神经网络可以有效的进行函数逼近或者信号逼近的特点。

In this dissertation, the design principle of the approach of typical fuse-warhead matching was given. According to the principle, this dissertation constructs four kinds of matching ways of fuse with warhead on the basis of obtaining necessary intercrossing information.

文中还给出了典型引战配合逼近的设计准则，并在获取必需的交会信息的基础上，依据典型引战配合逼近的设计准则，构造了四种不同的引战配合方式。

The sightline control strategy for bad measure precision is developed, and the control methods for vertical direction, approach direction and station keeping are presented.(2)The safe approach velocities are investigated for cuboid, sphere and cone keep out zone.(3)The design method for optimal trajectory under safety constraint is developed. The cone and cuboid keep out zone can be described using line constraint, and then optimal trajectory design can be translated to line programming problem under line constraint.(4) The design strategy of collision avoidance maneuver is discussed, and the collision avoidance scheme is analyzed for V-bar and R-bar approach.The control and trajectory safety in departure phase are investigated.

1提出了测量误差较大时平移靠拢段的视线控制策略，给出了横向、纵向和悬停的控制方法；(2)针对长方体禁区、球形禁区和锥形禁区三种禁区形式，研究了V-bar逼近和任意方向逼近的纵向安全速度计算问题；(3)提出了安全约束下的最优轨迹设计方法，将冲量和有限推力作用下的最优轨迹设计问题转化为线性规划问题，并给出了将锥形和方形安全区域约束转化为标准线性约束的公式；(4)探讨了紧急避撞机动的设计策略，分析了V-bar和R-bar接近的紧急避撞机动方案。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。