查询词典 curvature of curve

3D reconstruction is one of the most challenging problems in computer vision. This project uses CAD model to increase the accuracy,robustness and speed of 3D reconstruction and five different works are conducted: 1 research on space curve 3D reconstruction method based on high curvature point nad turning point; 2 free-form curve 3D reconstruction based on B-spline and BURBS; 3 Active surface affine reconstruction based on single frame; 4 Matching and reconstruction of 3D sparse points; Data fitting method based on the iteration of nearest point.

三维重建是计算机视觉中公认的难题，本项目使用CAD模型来提高三维重建的精度、稳健性和速度的思路，围绕着空间曲线和曲面的三维重建和匹配开展了以下五个方面的研究：1）基于高曲率点和拐点分割的空间曲线三维重建方法研究；2）基于B样条和NURBS表示的空间自由曲线三维重建方法研究；3）基于单帧图像的有源曲面仿射重建；4）三维离散数据的匹配与重建；5）基于迭代最近点的数据拟合方法。

Besides common geometric measurements such as distances and angles,a new measurement of average curvature energy defined for boundary curve segment is included in the set to describe curve feature.

除了常见的几何测量外，提出了一种平均曲率能量的测量方法来描述边界曲线特征。

This paper used a method of curvature circle replacing general curve,the authors obtain twouniversal formulas calculating the inherent frequency of relative oscillation in miniamplitude be-tween columns that have general section curve.

本文应用曲率圆弧近似一般曲线的方法，导出了具复杂截面曲线的等截面柱体在另一柱体上微幅摆动时固有频率的一般计算式。

If singular value curve is convex in the coordinates 'k' of maximum peak of curvature spectrum, then the number of effective singular values is k; if singular value curve is concave in the coordinates 'k', then the number of effective singular values is k-1, and this rule is tested by the signal processing examples.

如果奇异值曲线在曲率谱最大峰值的位置坐标k处是凸出的，则有效奇异值的个数为k；如果奇异值曲线在k处是凹进的，则有效奇异值的个数为k-1，通过信号处理实例证实了这种结论。

Degree B-Spline curve is chosen to fit the longitudinal settlement curves, which solves the problem of curvature continuum for joint notes due to its continuous second derivative vector and overcomes the efficiency and accuracy of computing curvature with 3 points by hand.

选取三次B样条方法对隧道纵向累计沉降曲线进行拟合，利用三次B样条曲线二阶导矢连续的特性，解决了拟合曲线在曲线连接点处曲率的连续性问题，克服了以往人工计算隧道曲率半径在效率和准确性方面的缺陷；并在此基础上，推导了隧道纵向变形曲率与纵向螺栓拉应力、相对弯曲与纵向螺栓剪应力之间的关系； 3。

A new curvature-based algorithm in free-form curve fitting was proposed to fit a 2D NURBS profile with an arc spline ,where a new form of curvature formula with matrix representation was also proposed,and then the arc spline tool path with G~(1) continuity was generated.

给出了一种平面曲线轮廓的圆弧样条拟合及刀具路径生成算法，该算法面向零件轮廓的光顺性刀具路径生成，通过应用曲线的曲率关系，对以NURBS表示的被拟合自由曲线按参数递增的方向用G1连续的圆弧或直线段逐段拟合，并生成相应的圆弧样条刀具路径，从而实现零件曲线轮廓表面的光顺加工。

For these two effective focal lengths, the spots on the image surface at zero view field, 0.7-view field and full view field are all inside the airy disc. The system MTF curve of each effective focal length are accordance with the corresponding diffraction limits curve. The biggest wave aberration is smaller than 1/4 wave lengths. The maximum field curvature and maximum f-theta system distortion respectively satisfies the precision demand of the laser marking machine in China.

系统像面在0视场、0.7视场和全视场的光斑都落在相应的爱里斑以内，系统的MTF曲线接近相应的衍射极限曲线，最大波像差小于四分之一波长，系统的最大场曲和最大f-theta相对畸变都很好地满足了国内激光打标机的精度要求。

The line of curvature isn't only a curve of space, but a special and a very important curve of surface.

曲率线不仅是一条空间曲线，而且是曲面上定义的一种特殊而重要的曲线。

A spherical curve is specified by one radius and has equal curvature at all points along the curve , much like the inside of a round ball.

8球面弧是指弧面上任意一点的曲率半径均相等，如同一个圆球体的内曲面。

For each patient, a 3D reconstruction of the spine was obtained from calibrated biplanar radiographs.3 The reconstructed models were then used to compute 4 indices of the thoracic segment: the Cobb angle, thoracic kyphosis (measured from T4–T12), axial rotation of the apical vertebra, and the orientation of the plane of maximum curvature with respect to the sagittal plane.22,2 Measurements of coronal and sagittal plane curvature were based on a curve fitted mathematically through the centers of the vertebrae.

对冠状面和矢状面的角度测量基于通过椎体中心的合适的曲度数学计算。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。