查询词典 approximate

As an approximate method,with the trigonometric function,the simple pendulum dynamical equation is simplified,and the approximate formula for the period of simple pendulum movement is presented.Comparison is made between approximate formula and exac...

对近似公式和精确公式进行了对比，最后进行了数值计算，结果表明，所得到的单摆运动周期的近似公式在大多数情况下都与精确公式符合的很好。

Three approximate methods (called as scaling, rectangle and trapezia methods respectively) for performance analysis of orthogonal space-time block code with M-ary phase shift keying and M-ary quadrature amplitude modulation over flat Rayleigh fading channels are proposed, and their approximate performance expressions are given-The analysis of approximate results shows that OSTBC can obtain full diversity orders.

在平坦瑞利衰落信道下，提出了3种正交空时分组码在MPSK和MQAM调制下的近似性能分析方法（分别称为放缩法、矩形法和梯形法），并给出其近似表达式。通过对近似结果的分析，OSTBC能获得满分集增益。

For a general parametric curve/surface, we usually cannot compute its exact implicit form. Even though its exact implicit form can be computed, the curve/surface implicitization involves relatively complicated computation and the degree is higher. Moreover, it may have unexpected components and self-intersections. All these unsatisfied properties limit the applications of the exact implicitization. So finding curve/surface approximate implicitization has become a practical problem. In this paper, we present an algorithm to solve the approximate implicitization of a given parametric curve by using a quadratic algebraic spline curve.

由于精确隐式化过程不一定可以实现，即使可以实现隐式曲线曲面的阶数高计算复杂，并且具有不希望的自交点和奇异分支，从而限制了隐式化的运用，所以寻求参数曲线曲面的近似隐式化问题成为很实际又重要的问题，提出利用二次代数样条曲线来实现一般平面参数曲线近似隐式化的一种算法。

If we hope to use a sequence of finite objects to approximate infinite objects, then we should know what kinds of infinite objects are approximable and how to approximate them effectively.

无穷形式对象可逼近的充分条件为了研究哪一类无穷对象可以逼近以及如何有效地逼近它们，我们用过程模式作为无穷对象上的计算的模型，用以刻画接受无穷输入、生成无穷输出的无穷对象上的计算。

The basic concept in these sections is replacing backward Euler's method by modified backward Eulers's method to approximate the characteristic differential equation and discretizing the convection-diffusion equation at the middle point of the approximate characteristic curve, which will make the convective term get up to second order accuracy.

这三节的基本离散方法是用改进的Euler公式代替向后Euler公式来近似特征微分方程，并且将近似特征线的中点作为离散节点，使得对流项的离散精度提高到二阶，对于扩散项，将其转移到待求时间层进行离散。

Considering the pitch deviation, pitch accumulative deviation, flank angle deviation and their combined influence on the pitch diameter, the authors present a complete differential optimal approximate model in this paper and use the ideal thread to approximate the actual thread radially and axially.

本文建立的螺纹中径当量全微分优化逼近模型，考虑了螺距偏差、螺距累积偏差和半角偏差本身及其相互间对中径的综合影响，并用理想螺纹在径向和轴向二维逼近实际螺纹。

In this paper, Galerkin method is employed. First, test functions to satisfy natural boundary conditions are selected. Then the approximate analytic formulations of the system frequency are derived. Meanwhile the approximate analytic formulation of the limit velocity is got.

采用直接法，首先选取满足自然边界条件的试函数，而后求出了系统固有频率的近似解析公式，同时也得到了极限流速的近似解析公式。

The relationship between transient response and shape design variables is highly non-linear, and the behavior of feasible domains is often not good, which may cause convergence difficulties. In order to improve convergence speed of iteration process, some algorithms the feasible domains adjusting, the adaptive move limit, the approximate line search and the approximate reanalysis, are adopted.

采用基于Newmark积分的直接求导法计算瞬态响应灵敏度，在序列二次规划算法中采用了可行域调整、近似—维搜索、自适应运动极限等改进技术，提高求解效率和收敛稳定性，以解决结构动态响应与设计变量的关系复杂、高度非线性，优化可行区域的性态不良等问题。

The WKB approximate method is one of effective approximate methods in the quantum mechanics .

WKB近似方法是量子力学中有效的近似方法之一。

"Approximate to","His description of the incident approximate of the fact.

3，他对事件的描述接近事实。

When this condition occurs, inbound replication with the source partner is stopped on the destination domain controller and event ID 2042 is logged in the Directory Services event log.

计算机密码学是研究计算机信息加密、解密及其变换的科学，是数学和计算机的交义学科，也是一门新兴的学科。

Instructions: click on the thumbnails to see a larger image, then use the left-right arrow keys to scroll through the slideshow.

使用说明：滑鼠点在小图上即可放大观赏。开启后键盘左右键可用来换照片。