查询词典 iteration

Firstly, the principle of the iteration method is presented, the characteristic of the method is analyzed. The downward continuation computation for model and practical data with noise of different variance is performed by means of iteration method.

首先介绍了迭代法的基本原理，分析迭代法的特点；然后利用迭代法对不同噪声水平的模型数据和实测数据进行向下延拓计算，研究噪声对迭代法的计算误差影响。

In order to speed up the convergence speed, the each one step of the Landwber iteration is discomposed into the matrix computation and solution and a quick iteration scheme is given for the matrix computation. The relevant accelerated algorithm is given too. Numerical example proves that the accelerated algorithm can quicken convergence speed, reduce the calculation burden, and overcome the obstacle of application of Landweber method of iterated regularization.

为了加快Landweber迭代收敛速度，将每一步Landweber迭代分解为矩阵计算和求解，对矩阵计算部分设计了一种快速迭代格式，并给出了相应的加速算法，通过数值实验验证了这种算法能够大大加快收敛速度，有效的减少计算量，解决了Landweber迭代正则化方法在实际应用中的障碍。

The reconstruction problem is ill-posed, so two optimal criterions, the least module and the smoothness criterion base on Tikhonov regularization technique, are introduced into reconstruction algorithm. Many regularization parameters choice strategies are investigated, and the TPA(Two—Parameter Algorithm) strategy which is based on the Morozov discrepancy principles, is implemented in two regularization reconstruction algorithms.Numerical experiment results show that the nonnegative and smoothness constraint condition can overcome the difficulty of iteration semiconvergent, preconditioned technique can improve convergence rate and reconstruction accuracy, smoothness regularization criterion can meliorate ill-posed problem of reconstruction and enhance iteration stability, and the TPA is an effective strategy of regularization parameters choice.

数值试验表明：在共轭梯度法中引入非负约束和光滑约束改善了迭代的"半收敛"性，非负约束保证了解的非负性，光滑约束抑制了重建解的振荡现象，约束算法的重建精度与无约束算法相比大幅度提高；在约束共轭梯度重建算法中引入预优技术，可以加快算法的收敛速度，提高迭代的稳定性和重建精度；引入光滑准则的正则化技术可以有效改善图像重建问题的不适定性，加快迭代的收敛速度，提高迭代的稳定性和图像重建质量，计算正则参数的TPA算法在闪光照相图像重建中是有效的。

A criterion for divergence of iteration is given and the covergence speed and covergence acceleration for iteration with multiple root are investigated.

给出迭代发散的一个判定，并讨论重根情形下迭代的收敛速度和迭代加速。

A differential iteration solution is presented by combining the features of bidirectional iteration method, Newton′s interpolation formula and direct differential method.

将"双向迭代"、牛顿二次差商以及直接微分等分析手段有效地结合起来，形成一种被称为"微分迭代"的波导方程解析方法。

In this paper, Newton iteration formula for computing normal depth and critical depth was put forward by mathematical transformation of uniform flow equation and critical flow equation of circular section tunnel. Then, the relationship between the corresponding central angle and the introduced parameters was analyzed. An approximate formula for angle was obtained according to optimal uniform approximation principle. Using this approximate formula as initial value of iteration formula, a direct formula for calculating normal depth and critical depth of circular section tunnel was established after its first iterative.

该文通过对圆形断面均匀流方程与临界流方程的数学变换，分别得到其正常水深与临界水深的牛顿迭代公式，同时，通过对正常水深与临界水深对应的中心角与引入参数之间关系的分析及数值计算，利用最优一致逼近原理分别得到了正常水深与临界水深对应中心角的近似计算式，并以此近似计算式为初值，用迭代方程进行一次迭代得到了圆形断面均匀流水深与临界流水深的直接计算公式。

Based on the MDP, an algorithm including numerical iteration and policy iteration is then proposed.

文末仿真结果验证了该方法的正确性和有效性。

This idea comes from the appearance of the curse of dimension in computational process, for example, in Markov decision processes, its not practical for improving policy computation using the general policy iteration or value iteration method.

当系统的计算出现维数灾难时，比如在Markov决策过程的求解问题中，如果系统的动作空间非常之大，那么利用一般的策略递归算法或值递归算法，来进行策略的改进计算是不实际的。

Given a skip-parser type SkipT, skip_parser_iteration_policy creates a scanner iteration policy that skips over portions that are recognized by the skip-parser. This may then be used to create a scanner. The scanner_policies class wraps all scanner related policies including the iteration policies.

给与一个类型为 SkipT 的跳读分析器，则 skip_parser_iteration_policy 将创建一个会跳过被跳读分析器所匹配的内容的扫描器迭代策略。scanner_policies 类封装了包括迭代策略在内的所有与扫描器相关的策略。

Based on prestressed steel beams, considering effect of the method of construction to slip and stress increment, accoding to conception that procedure of calculation reflects the procedure of construction and change of structural internal force, making good use of the method of section conversion and making iteration reflect the coupling of slip and stress increment, bringing forth a method of iteration and modified stiffness to calculate the deflection of prestressed composite steel-concrete beams in normal servicing prase.

以预应力钢梁为基础，充分考虑施工方法对结构滑移和应力增量的影响，依据设计计算中反映施工过程和结构受力变化过程，通过截面换算，以循环迭代法来考虑滑移和预应力钢束的耦合作用，提出了计算预应力钢—混凝土组合梁正常使用阶段挠度变形的迭代—修正刚度法。

A historical region of southwest France between the Pyrenees and the Garonne River. The duchy of Aquitaine was joined with France after the marriage of Eleanor of Aquitaine to King Louis VII in1137, but its possession was disputed after her subsequent marriage to Henry II of England.

阿基坦法国西南部一个历史地区，位于比利牛斯山和加隆河之间，在1137年阿基坦的埃莉诺与国王路易斯七世结婚之后阿基坦公国加入法国，但当她再嫁英国亨利二世后，其归属权便受到争议

There are moments when I look at the smiling , happy faces of my expectant staff and wonder how they will cope when confronted by an outraged housemaster along with an unrepentant and recalcitrant bleached blond teenager in 18 years ' time .

有时候，我看着那些满怀期待的员工微笑，幸福的脸，想着当他们遇到一位愤怒的宿舍管理员和一位不知悔改，叛逆，而且将头发染成白色的18岁少年时，他们会如何处理。