查询词典 calculus of approximations

In order to avoid the Maratos effect, the merit functions used are approximations to Fletchers differentiable exact penalty function. Global convergence is proved on some conditions, and some numerical results are given .

为避免Maratos效应，此方法采用Fletcher的光滑精确罚函数的逼近形式作为价值函数，在一定条件下证明了算法的全局收敛性并且给出数值结果。

However, to establish global convergence for these latter methods, one must enforce either sufficient decrease conditions (the Armijo-Goldstein-Wolfe conditions)or a fraction of Cauchy decrease condition - all of which rely on explicit numerical function values, as well as explicit approximations to the directional derivative at the current iterate.

但是，为了保证后面方法的全局收敛，必须有足够的减少条件（Armijo-Goldstein-Wolfe条件）或者部分柯西减少条件——它们全都依赖于外在的数值函数值，就和在当前迭代逼近方向导数一样。

Highly accurate approximations of the elliptic function are obtained in this paper through the use of Gauss transformation, which could not be obtained by the traditiona...

运用高斯变换法求椭圆函数的高精度近似值，解决了过去沿用椭圆积分表达不到精度要求的困难。

It provides a way to find optimal lower dimensional approximations of the given data, and It enormously reduce the storage of the data which is needed when the physical processes is recurred. The physical process can be described in series expansion function that only is related to the time and space. It is optimal approximation of the given data in a certain least squares optimal sense. The most obvious advantage of the method is that it reduces the computation cost and computation time markedly.

它提供了一种描绘物理过程的有效方法，该物理过程可以写成一个只与时间相关的函数和一个只与空间相关的函数的展开式序列，且它们在均方意义上是最优的，在展开式中只需要少量的项数就可较准确地描述该物理过程，因此降低计算维数、减少计算量和节省计算时间是这个方法最明显的优点。

The following results are obtained:(1)a derivative formal context of an information system can be induced by the notion of nominal scale and the technique of plain scaling in formal concept analysis;(2)some core notions in rough set theory such as partition,upper and lower approximations,independence,dependence and reduct can be reinterpreted in derivative formal contexts.

利用形式概念分析中名义梯级背景的概念，对信息系统进行平面梯级得到了衍生的形式背景。证明了粗糙集理论中的划分、上下近似、独立、依赖、约简等核心概念都可以在相应的衍生背景中进行表示。

The approximations can be used as the initial guess and pre-conditioner in the stabilized biconjugate-gradient fast Fourier transform algorithm for computing integral equations, and hence a hybrid DTA-BCGS algorithm with higher efficiency is formed.

这两种近似可以作为计算积分方程稳定型双共轭梯度快速Fourier变换算法的初始猜测值和预条件因子，从而形成效率更高的混合DTA-BCGS算法。

The model impacts a pair of tunable parameters on the tolerance relation derived from an IDT between objects by attribute values and a threshold on inclusion relation between subsets to form lower and upper approximations in the model for processing the table.

在该模型中，设定一对可调的参数使其作用于由IDT衍生出的限制容差关系，从而形成上下近似集。

Mathematics A method of solving equations in which the errors resulting from an initial approximation are reduced by succeeding approximations until all errors are within specified limits.

张驰：处理方程式的一个方法，由最初的粗略估计时产生的错误在随后的估计时得到逐渐减少直到所有和错误都在特定的限制范围之内

Since any approximations, such as numerical Laplace inversion, backward differentiation formula, nonlinear model of switch, do not exist, the new algorithms are accurate.

由于该方法不存在任何极限近似问题（数值拉普拉斯反变换法，后向差分法，非线性开关模型法等），因而它是一种精确计算方法。

Stationary NA sequences; empirical measure; large deviations principle; linear processes; functional law of the iterated logarithm; strong approximations; LPQD sequences; m-dependent random element; precise asymptotics; the central limit theorem for the sum of random number

基础科学，数学，概率论、数理统计平稳NA序列；经验测度；大偏差原理；线性过程；泛函型重对数律；强逼近； LPQD序列； m-相依随机元；精确渐近性；随机指标中心极限定理

You can snipe the second and third union leaders from this position.

您可以鹬第二和第三工会领袖从这一立场出发。

Aiming at the currently shortage of XML streams quality detecting, this paper proposes a new forecasting method of XML streams quality by least squares support vector machines, which is used the method of XML keys' vector matrix as windows, and vector product wavelet transform to multilevel decompose and refactor the XML streams series, that can fulfill real-time checking demand of XML quality, and ensure constraint, consist- ency and integrality. For even more adapting net load, it proposes a control strategy by weight and adaptive adjustment to ensure XML streams quality.

针对当前XML数据流质量检测存在的不足，提出构建XML键的矢量矩阵作为窗口，利用矢量积小波变换多级分解与重构XML数据流，再结合最小二乘支持向量机对XML数据流质量进行预测的一种方法，满足XML数据流质量重构时实时检测的要求，保证XML数据的约束性、一致性与完整性；为了更好的适应网络负载，采取加权与自适应窗口调整等调度策略充分保证XML数据流的质量检测。