平面曲线

A plane cubic curve having a single loop, a node, and two ends asymptotic to the same line .

平面立方曲线平面的立方曲线，具有一个拱形、一个交点和逐渐接近同一条线的两个端点

The flap of an envelope.A plane cubic curve having a single loop, a node, and two ends asymptotic to the same line.

平面立方曲线平面的立方曲线，具有一个拱形、一个交点和逐渐接近同一条线的两个端点

Shaped like a hump or an arching curve .A plane cubic curve having a single loop, a node, and two ends asymptotic to the same line.

平面立方曲线平面的立方曲线，具有一个拱形、一个交点和逐渐接近同一条线的两个端点

The pencil of plane quadratic lines is the foundation for studying plane cubic curve and hig-her plane curves.

平面二次线束是研究平面三次代数曲线和高次曲线的基础。

Second, transient flow for vertical well and fractural well in porous media with arealanisotropy has been researched in this paper. The analytic solution for vertical well andsemi-analytic solution for vertical fractural well is developed by using image inversion,superposition principle, Laplace transformation, Fourier transformation, as well as theirinverse transforms, and storage and skin are taken into account. For vertical fractural well,influence of pressure and productivity is studied when the orientation of artificial fractureisn't in accordance with the direction of major permeability, it is fundamental to evaluatepotential and analyze well test data.

文中研究了平面各向异性储层不定常渗流问题，建立了平面各向异性储层交叉直线边界中一口直井渗流的数学模型，利用镜像反演、Laplace变换、Fouier变换及其反变换推导了不同边界条件下直井的Laplace空间解析解，考虑井储和表皮的影响，分析了曲线特征及影响因素的敏感性曲线；并运用影响椭圆及Duhamel叠加原理，推导了平面各向异性储层中垂直裂缝井的压力分布方程，考虑了水力裂缝与主渗透率轴成一定角度对压力及产能的影响，为垂直裂缝井的产能评价及试井分析提供依据。

The computational methods of line element conic curve s tangent point decided by any line on projective plane is presented on the basis of this study.

从实际计算的角度出发，使用N矢量表示视平面上的点和直线，并由线素二次曲线的射影定义推导出线素二次曲线的N矢量方程；在此基础上，给出了射影平面上任意一条直线所确定的线素二次曲线切点的N矢量的计算方法。

In this paper,the rational approximation of the offset curve of Bézier curves is obtained when a polynomial of symmetric power basis is used to approximate the norm of parametric speed of Bézier curves.

等距曲线逼近技术的关键在于参数速度的逼近，文章用S幂基多项式逼近平面Bézier多项式曲线的参数速度模长，得到Bézier多项式曲线的等距曲线的有理逼近曲线，所得有理多项式逼近曲线与等距曲线在端点处能够达到高阶插值。

We shall explore the theory and computational methods of the singularities of rational planar curves and rational space curves fromμ-bases.

本文中我们将首先讨论基于μ基的平面有理曲线与空间有理曲线奇点的理论及计算。特别地。对平面有理曲线。

This paper establishes cubic spline function, analyzes subsection curve function and curve slope and curvature, at last decides to place the curve especial points which can be obtain easement curve length and other line parameters, such as the ZH point (end of line and beginning of transition curve), the HY point (end of transition curve and beginning of circular curve), the QZ point, the YH point (end of circular curve and beginning of transition curve), the HZ point (end of transition curve and beginning of line).

针对公路平面线形的8种组合类型，其线形元素特征则由最基本的直线、圆曲线、缓和曲线组成的特点，解析三次样条函数模型，得分段曲线函数、曲线斜率、曲率，从而确定曲线特征点（直缓ZH点、缓圆HY点、曲中QZ点、圆缓YH点、缓直HZ点）位置，进而得到曲线缓和曲线长度及其他线形参数。

On the basis of equivalent planar pitch,the tooth profile of the equivalent gear was gotten through simulation when the pitch curve of the gear shaper rolled on the equivalent planar pitch curve.

以平面当量节曲线为基础，通过确定插齿刀的节圆沿平面当量节曲线做纯滚动时插齿刀上各点的运动轨迹，模拟了插齿加工包络出当量齿轮的齿形过程，将非圆锥齿轮的设计转化为平面齿轮的设计，简化了非圆锥齿轮的设计。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了