Compact totally real submanifolds in a complex space form without parallel mean curvature vector

The mean curvature vector of surfaces in r~ n

R~n中曲面的平均曲率向量

The paper describes a high resolution, high accuracy and simple method of measuring dymamic angle by means of optical self-collimating of concave mirror curvature center.

用四球面反射镜曲率中心光学自准方法，通过测量自准像位移来计算弯沉角，是一种高分辨率、准确、简单地测量方法。

Non-standard Design for Concave Curvature Radius of Belt Conveyor

带式输送机凹弧段曲率半径的非标设计

Finally, a sufficient condition ensuring the submanifolds have positive sectional curvature is obtained.

最后，给出了使截面曲率大于零的一个充分条件。

In this paper, some properties of totally real and totally umbilical submanifolds of a complex projective space are obtained. We also prove that a compact totally real submanifold with positive curvature and parallel mean curvature vector of a complex projective space must be pseudo-umbilical.

获得了复射影空间中全实全脐子流形的若干性质，并且证明了复射影空间中具有平行平均曲率向量的正曲率紧致全实子流形必是伪脐的。

On the Instability of Integral Currents and Harmonic Maps in Riemannian Manifolds of Positive Curvature

正曲率流形上积分流与调和映射的不稳定性

On the other hand, a positive curvature would imply that three-dimensional space is finite and closed.

另一方面，一个正的曲率将必然说明三维空间是有限的，而且是封闭的。

Positive curvature has been a frequent subject in Riemannian geometry.

曲率是黎曼几何中的热门研究课题。

Then, make use of the positive curvature extreme points which correspond to each silhouette segment, to combine fine silhouette segments. So we can obtain the silhouette, which can represent limbs of human body.

然后，利用每个轮廓片段对应的正曲率极值点将细小轮廓片段进行合并，从而获得能够单独表示人体肢体的轮廓。

Could it be said that God favors positive curvature?

难道上帝对正曲率空间有偏爱？

Grinding and Inspection of Spherical Mirror with Long Curvature Radius

特长曲率半径球面反光镜的磨制与检测

Test of spherical surface with small curvature and large aperture

小曲率大口径球面的检验

In this paper we study the moduli space of surfaCes with one family ( or two families) Of spherical lines of curVature in R3 by use of E. Cartan's theory of exterior differential systems.

用E.Cartan的外微分系统理论，研究了R3中一族（或两族）曲率线为球而曲线的曲面的模空间。

Spherical curvature radius was optimized through controlling the exit rays and using the automatic optimization function of optical design software.

通过对出射光线的控制，利用光学设计软件的自动优化功能，优化出满足条件的球面曲率半径。

Measurement of lens focal length and spherical curvature

透镜焦距及球面曲率的测量

What changes are necessary when a spherical curvature is introduced in the substrate?

当一个球面曲率引入基底时需要有什么改变？

Investigation on increasing measurement accuracy of radius of spherical curvature

提高球面曲率半径测量精度的方案探讨

Meanwhile, a concave reflector with suitable curvature radius and large section radius improves the levitation capabilities of the potential well near the reflector under mode 4.

另外，采用适当曲率半径和较大截面半径的凹球面反射端能够提高模式4下靠近反射面的一个悬浮位置的悬浮性能。

Among them there were 40 cases with lumbago, 39 cases with lumbar lateral curvature, 40 cases with the straight leg-raising maneuver test with positive results;

腰痛40例，腰侧弯39例，直腿抬高试验阳性40例；

Conclusions: Lateral curvature should be associated with the rotatory and the excessive lateral curvature should be avoided when operating the manipulations of neck.

结论：侧弯（旋转）伴有一定程度的旋转（侧弯），行颈部推拿术治疗时应避免过度侧弯。