查询词典 curvature of a curve

In 1906, da Rios, a student of Leivi-Civita, wrote a masters thesis modeling the motion of a vortex in a viscous fluid by the motion of a curve propagating in R~3, in the direction of its binormal with a speed equal to its curvature.

很久以后，1971年Hasimoto证明了这个系统和非线性Schrodinger方程 q_t=iq_(ss 1/2|q|~2q是等价的。

The locus of the center s of curvature of a given curve.

渐屈线一给定曲线率中心的轨迹

In order to study the popular curve shortening flow in the plane, Gage[3] has shown in 1983 the following inequality, if k is the signed curvature of a closed convex plane curve γ with length L and enclosing area A, then one gets Gage calls it an isoperimetric inequality in [3], but he does not show that the equality holds if and only if the curve γ is a circle, while as an isoperimetric-type inequality, one should prove this kind of result.

Gage称之为等周不等式，但他没有证明其中等号成立当且仅当，γ为圆周，而作为等周型的不等式是应该证明这种结果的，本文我们利用单位速率外法向量流，通过努力证明了这种结果，从而把Gage不等式加强成更加等周的形式。

The Fary-Milnor theorem states that the total curvature of a knotted simple closed curve in R^3 is greater than 4π.

Fary-Milnor 定理：一条空间中的简单封闭扭结其总曲率必大於4π。

First, the relative curvature of a certain curve at its first end and the directional angle of the first port tangent vector of that curve as well as the weight factor of the interpolation curve are given, then all the other control vertexes can be gotten by using the conditions of G continuity, and a method to construct transitional curves is also introduced so that we can get the closed interpolation curve which achieves G continuity globally.

首先给定某段曲线的首端相对曲率和该段曲线的首端切矢量的方向角以及插值曲线的权因子，然后利用G2连续条件求出其余控制顶点，并给出了构造过渡曲线的方法，得到了G2连续的闭插值曲线。

The locus of the centers of curvature of a given curve .the inward force on a body moving in a curved path around another body.

在一个物体沿曲线轨迹围绕令一个物体运动的时候产生的向内的力。

The curvature of a curve; the magnitude of the derivative of its unit tangent vector with respect to distance on the curve:.

曲线的曲率；为单位切向量对距离取导数所得向量的大小

A method of construct a quadratic uniform B-spline curve through data points is given.If the relative curvature of a certain curve on the first control point and the direction angle of the first port's tangent vector is given,here can get the whole curve by using the character of the port of quadratic uniform B-spline curve.

提出了一种二次均匀B样条插值曲线的构造方法，首先给定某一段曲线首点的相对曲率和该段曲线的首端切矢量的方向角，利用二次均匀B样条曲线的端点性质，求出其余各段曲线控制顶点，来生成整条插值曲线。

DT/ds| The curvature of a curve; the magnitude of the derivative of its unit tangent vector with respect to distance on the curve:|dT/ds

曲线的曲率；为单位切向量对距离取导数所得向量的大小

From this viewpoint, we fulfilled to control the step-size with the curvature of integral curve. The step-size is smaller in calculating these points that the value of the curvature is bigger and the step-size is bigger in calculating these points that the value of the curvature is smaller, which is rather reasonable choice and is also a creative point in this paper.

从这个想法出发，在文中实现了以积分曲线的曲率控制步长大小的作法，在曲率大的点步长小，而在曲率小的点步长大，这是非常合理的选择，也是本文的一个创新点。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。