查询词典 differential method

In the last a few years, the differential solution of wave equation was hold up by the condition of computation. Kirchhoff integral method rose in the initial stages of the ninetieth decade of last century.

前几年波动方程微分解由于受计算条件的限制而难于在地震资料处理过程中发挥作用，上世纪90年代初发展起来的克希霍夫积分方法，因本身存在的缺陷也难于在深层地震资料处理中取得新的突破。

A method was developed for the determination of nitrobenzene in aniline by differential pulse polarography .

试验发现硝基苯在-0.57V处有一个良好的差分脉冲极谱峰。

And it is a major method in the diagnosis, differential diagnosis of the mass or nodular of lung.

是肺部团块状，结节样病变的诊断和鉴别诊断的主要手段之一。

By using the classical or nonclassical Lie symmetry method we can get amount of exact solutions of the nonlinear differential equations.

李群方法是研究非线性微分方程的有力工具，应用经典或非经典李群方法，可得到大量非线性微分方程的精确解。

By using the method of upper and lower solutions ,we obtain the existence of solutions for boundary value problem of second order integro differential equations of Volterra type in a normal cone.

利用上、下解法在正规锥上证明了二阶非线性Volterra型积分微分方程边值问题解的存在性。

Since two curves have the same coordinates and unit normal vector at the contacting point, the problem of the mesh of two planar curves is transformed into an ordinary differential equation by vector analysis. We have the solution to the equation by numerical method and computer calculation. After repeating the way of computing the solution to the equation, we have the contacting points.

因两曲线於接触点的位置相同，单位法线向量相等，由向量分析使曲线接触问题转变为常微分方程式，藉助数值计算与电脑运算得到方程式解，重覆计算方程式的解即可得每一接触点的位置。

The interpolate algorithms of three-order NURBS curve and double three-orders NURBS surface are presented. The expressions of partial derivative and normal curvature of NURBS surface are derived by the theory of differential geometry. The geometric characteristics of different curvature area of the free-form surfaces are analyzed in detail. All these work lays a theoretical foundation for constructing the cutter location calculating model of free-form surfaces NC machining. 2 On the basis of analyzing the methods of cutter path generation, the standard of evaluating the various methods of cutter path generation is presented. The method of generating cutter path with constant scallop height is presented for the first time.

本文以提高复杂曲面多坐标数控加工精度和加工效率为目的，在对国内外研究现状进行深入分析的基础上，对数控编程中各环节的关键技术问题进行了深入研究，主要内容包括以下几方面： 1 分析了复杂曲面各种造型方法的优缺点，给出了根据各种边界条件所确定自由曲面的NURBS表示方法以及三次NURBS曲线曲面反算算法；用微分几何理论推导了NURBS曲面的偏导矢及法曲率计算表达式；对曲面不同曲率特性区域的几何特征进行了深入分析，为建立复杂曲面的数控加工刀位计算模型奠定了理论基础。

A simple of improving the differential frequency by D flip-flop is introduced. The method is verified by timing analysis. Numberical application conditions are given out. The reason for the error production is analyzed and the maximum error range are calculated.

介绍了D触发器差频的方法和应用条件，用最基础的时序分析的方法，对D触发器差频做一个理论上的验证，定量给出应用条件，并分析了产生误差的原因和最大的误差范围。

After solving the bubble radius change rule, the velocity of the bubble growth and the collapse process is gained using numerical differential coefficient method.

求解出空化泡半径变化规律之后，本文应用数值微分的方法，求出不同初始半径空化泡壁的膨胀和崩溃速度。

But the numerical differentiation process is very sensitive to even a small level of errors. In contrast it is expected that on average the numerical integration process is much less sensitive to errors.

在DQ方法的基础上，本文提出了一种新的方法——基于最高阶导函数插值的微分求积(differential quadrature method based on the highest derivative，简称DQIHD)方法。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。