代用

Calculus can be used to find approximate solutions to equations, in methods such as Newton's method , fixed point iteration , and linear approximation .

积分可以用来寻找近似解方程，在方法，如牛顿法，不动点迭代和线性近似。

In this paper, we have been solved Fresnel integral equations by the numerical iterative method in virtual confocal unstable cavity with the strip mirrors of cylindrical surfaces.

用数值迭代方法求解了柱面条状虚共焦非稳腔的积分方程组。对相同及不同的菲涅耳数NF和不同的放大率m等情况进行了数值计算。

A systematic study on computing the integral curvature line on NURBS surface is presented. Discrete normal is used to simplify calculation of the second fundamental form of the surface, resulting in accelerating the Euler iteration process in solving the differential equation of curvature line. Discrete points on the curvature line are then obtained and approximated by an explicitly presented B-spline curve on the NURBS surface using singular mixed interpolation and capable of controlling the error within a given tolerance.

对NURBS曲面的曲率线的积分进行了系统的公式推导，并利用NURBS曲面的离散法向量有效地简化了曲面第二基本量的计算，加速了Euler法迭代求解曲率线微分方程的过程；在求得曲率线上的离散点集以后，应用奇异混合插值技术，在可控精度内把曲率线用显式直接表示为位于NURBS曲面上的B样条曲线。

Based on the Saint-venant equations describing the channel flow movement, the nonlinear algebraic equations derived by the use of Preissmann weighted implicit four-point scheme are solved with the Netwon-Raphson method. A combined Gauss main-element elimination method with compress-storage technique is proposed. The relaxation iterative method for solving branch river networks is extended, which can turn the problem of any complex river networks into the problem of a series of single rivers. The coupling of hydraulic model with water quality model is built up. The combined model was applied to a large complicated river networks with numerical hydraulic structure which influenced by strong tide, storm and heave rain. Visualization of computational results is realized by means of MapInfo, which displays the computational results in fast, convenient and accurate way.

水力模型以描述河道洪水波运动的Saint-Venant方程组为基础，用Newton-Raphson方法直接求解按Preissmann加权四点格式进行离散所得的非线性代数方程组，提出了压缩存贮形式的Gauss列主元消去法并对数值解的收敛性进行了讨论；将支流流量的松弛迭代方法从树状河系推广到了环状河网，使任意复杂河网水力计算的问题都可化为一系列的单一河道的水力计算问题；建立了水力模型与水质模型的联接，初步应用于既有洪水、暴雨、强潮等综合影响，又存在多种水工建筑物及水力调度问题的大型复杂河网中的非恒定流水力、水质计算问题；利用MapInfo对计算结果的可视化进行了研究，有利于决策者快速、方便、准确地作出决策。

With the use of the thin process theory, the Probability Generating Function of the IBP is obtained. An iterative algorithm, which can be used to calculate the IBP probability distribution, is presented.

用稀疏过程理论得到IBP的概率母函数，提出了一种迭代方法计算IBP的概率分布，并就突发源的等价描述进行了讨论。

The tasks that would take most of the programming effort in C (finding line delimiters, generating substrings, etc.) are easily tackled using iterators.

在C语言中需要很多编程工作的任务用迭代器是一个简单的工作了（比如查找一个分界符，或是生成一个子串）。

The computing of latitude is the key of geodetic coordinate transformation from geocentric coordinate which conventionally uses iterative methods.

大地纬度的解算是从地心直角坐标到大地坐标变换的关键，通常都用采用迭代法实现。

Cephalotaxine ester of 2-oxo-6-methylheptanoic acid was treated with lithium diisopropylamide and Me O-(1-methoxyisopropyl)glycolate to give a mixture of homoisoharringtonine and its stereoisomers with 56% yield. The four stereoisomers separated by TLC showed identical mass spectra and almost superimposed IR but with different 1H NMR spectra. The configuration of the 2'-C and 3'-C of the four isomers were postulated based upon their 1H NMR spectra as compared with the 1H NMR spectra of isoharringtonine and its stereoisomers.

2-氧代-6-甲基庚酰基三尖杉碱(3)与0-(1-甲氧基异丙基)羟基乙酸甲酯(4)在强碱性试剂二异丙胺锂存在下，起亲核加成反应，反应中间体5在室温用酸性丙酮水解，得到一种新的三尖杉酯类生物碱一一高异三尖杉酯碱(6c)及其立体异构体(6a、6b、6d)的混合物，产率56%、通过制备薄层层析分得这四个立体异构体，它们的1H NMR和异三尖杉酯碱及其立体异构体的1H NMR类似，推定了它们的绝对构型。

This makes the suggested standard of harmonic analyzer feasible for practical use.

但这个方法用传统的处理方法（高斯消去法或迭代法求矩阵的逆）付诸实施时，将会碰到计算时间很长的困难，因而使测量的实时性受到很大的妨碍。

Get your seeds your heritage and heirloom seeds so that we can continue to grow our own food.

请用你们自己的种子——你们传统的或祖代相传下来的种子，这样我们就能继续种植/栽培我们自己的粮食。

Lugalbanda was a god and shepherd king of Uruk where he was worshipped for over a thousand years.

Lugalbanda 是神和被崇拜了一千年多 Uruk古埃及喜克索王朝国王。

I am coming just now,' and went on perfuming himself with Hunut, then he came and sat.

我来只是现在，'歼灭战perfuming自己与胡努特，那麼，他来到和SAT 。