曲率

This paper first summarizes recent researches on this topic, and then proposes some methods for curve modeling with cubic algebraic curve based on pure geometric constraints that involve control points, tangent directions and curvatures.

然后提出了一种基于几何约束的三次代数曲线的插值方法，该方法完全通过几何量如控制顶点、切线和曲率来控制三次代数曲线的形状，使得对三次代数曲线的编辑与对三次 B-样条曲线的编辑一样灵活方便。

The Topcon KR8100 automatic optometry was applied to examine the refractions and corneal K readings. All the patients received subjective refraction examinations. Allegretto Wave Analyzer was applied to detect the wavefront aberrations of the eyes.

使用日本拓普康公司生产的KR8100自动验光仪的人工晶状体眼模式测量患眼屈光度及角膜曲率，进行主觉验光，使用Allegretto Wave Analyzer波前像差分析仪检查患眼的波前像差情况。

In chapter 5, we present the analytic spectrum and light curve of these synchrotron radiating electrons, applying a treatment more reansonable and stricter than methods in the literature and convenient for calculating those of synchrocurvature to reveal physical nature of the magnetic field formation and acceleration of particles in shock.

在第五章，我们给出了这些电子能谱的解析同步辐射谱和光变曲线。我们的处理方法比文献中的方法更合理且更严格。它也更方便我们下面利用同步曲率机制去计算余辉的辐射谱和光变曲线，以期揭示激波中磁场形成及粒子加速过程的物理内涵。

An adaptive grid scheme controlling cell area is used to generated grids in the divergent section of symmetric annular nozzle, and the generated grids are used in the flowfield calculation through the uncoupled way. The elliptic equations are used to generate grids in three dimensional regions of FDN divergent section, the source terms used in the equations employ a mathematical form which is independent of the boundary shape and of the boundary grid point distribution, the free parameters contained in the source terms are determined by the two restraint conditions, the intersection angle of transverse grid lines with boundaries and the local curvature of the transverse grid lines at the boundaries, and the interior grid distribution controlled directly by the grid point distribution assigned on the boundaries is realized, it makes the grid more clustering near the nozzle wall. For the generated grids in the whole computational regions have a good smoothness and orthogonality, the accuracy of calculation in the flowfield is ensured.

对轴对称的环形喷管采用控制网格面积的自适应网格方法对扩散段部分进行了网格生成，并通过非耦合方式应用于喷管的流场计算中；对强制偏流喷管扩散段内的三维区域采用椭圆型方程进行网格生成，方程中的源项采用了与边界形状和边界网格点分布无关的数学形式，源项内的自由参数由横向网格线与边界的交角及横向网格线在边界处的局部曲率两个约束条件来确定，实现了由边界上的网格分布直接控制内部的网格点，使壁面附近具有较密集的网格，并且在整个计算区域内的网格都具有良好的光滑性和正交性，从而保证了流场计算的准确性。

The mechanics model of a ball screw was developed considering the factor of lead angle,and the main curvature of the helical surface was deduced using differential geometry method,and the effect of lead angle on the elastic deformation was analyzed.

考虑螺旋升角的因素，建立了滚珠丝杠副的受力模型，应用微分几何理论推导了螺旋面的主曲率，并进一步分析了螺旋升角对滚珠丝杠副弹性变形的影响。

Quantity of angular motion in the sagittal and coronal planes is likely to provide protection against adjacent-segment disease. Also important is the quality of motion, including radius of curvature, shear properties, and location of the instantaneous axis of rotation.

在矢状面和冠状面的角活动度的测量可能提供阻止临近节段疾病的方案，通用重要的是活动度的质量，包括曲率半径，剪切力的性质，转动瞬轴的位置。

It is noted that control varies of velocity and angular velocity are definied by structure equations and Gaussian curvature.

指出速度控制变量和角速度控制变量完全由结构方程和曲面的高斯曲率决定。

In general, smaller grain size and greater angularity tend to increase the porosity while an increase in range of particle size tends to decrease porosity.

通常，颗粒越小曲率越大孔隙度越大，而当颗粒尺寸增大时孔隙度会减小。

Methods: Thirty children who are anisometropia were analyzed using ultrasonic, the refraction and the keratometry were also be taken.

对30例屈光参差儿童的双眼进行了超声生物测定检查，同时进行角膜曲率测量和验光。

"Because a straight line can be thought of as an arc of a circle of infinite radius, its curvature is zero."

直线可视为半径无穷大的圆，曲率为0

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐