截面曲率

Direct difference is sensitive to noisy data, so a threshold limitation is given, which can not only filter the result from noisy data but also pick edge points up according men's desire. On the other hand, artificial intelligence is used for segmentation in reverse engineering. Because the essence of segmentation is clustering similar characteristics and self-organizing feature mapping is one function of neural network, SOFM network is used for segmentation in the thesis, coordinates and normal of data points is took as the characteristics vector.

第二种方法，基于双向角度微分的边点提取法，针对三维正交模型采用基于截面线的方式组织数据，此方法比基于曲率半径方法更简洁，不用进行曲面拟合，大大提高了计算速度；计算过程中由数据点的直接差分逼近微分，但直接差分对数据误差敏感，为此，本文提出了阈值过滤的方法，一方面过滤了数据误差在计算结果中引起的噪音，另一方面可以按照设计意图控制边点的提取；来决定是否提取光滑交接的边点。

Based on this result, neutral axle and curvature radius of different section is developed.

应力理论由轴向力的平衡得出积分，在此基础上推导出曲杆不同的截面的中性轴，曲率半径。

Fig.7shows the comparison of radius of curvature and cross-sectional deformed shape between the experiment and FE simulation.

图7所示为曲率半径和横截面形状在试验和有限元模拟中的比较。

Sixthly, research on seismic performance of repaired HSC column after hightemperatures The nonlinear whole process analysis method of reinforced concrete is used.Programs of moment-curvature and shear force-displacement of repaired HSCcolumn are developed after exposed to four sides and two symmetrical sides fire.Seismic performance of repaired reinforced HSC column after fire is studied. Byanalyzing the calculating results, the corresponding formulas of characteristicparameters of their skeleton curves of repaired HSC column after fire are proposed,and it is compared with corresponding curve of unfired columns.

火灾后已修复高强混凝土柱的抗震性能研究利用钢筋混凝土非线性全过程分析方法，编制了火灾后(包括四面受火和双面对称受火)已修复高强混凝土柱截面弯矩一曲率关系和剪力—位移关系的计算程序，对火灾后己修复高强混凝土柱的抗震性能进行了研究，通过对计算结果的分析和整理，给出了火灾后已修复高强混凝土柱M-φ及P-△骨架曲线特征参数的回归计算公式，并将上述曲线与未受火柱的相应曲线进行了比较。

Using the solid model, FEM model of the taper leaf spring could be constructed by mapped mesh in the software of ANSYS.

摘 要：根据每一片变截面钢板弹簧在自由状态下的三维尺寸、曲率半径和自由弧高，利用Unigraphics的二次开发功能，建立每一片钢板弹簧的实体模型。

By means of using a disc cutter with a concave end instead of traditional ball-ended or flat-ended ones,and adjusting the cutter axis to move relatively to the component being machined according to some special rules,the envelop formed by the trace of the tool-nose in each pass and the required surface have the same derivatives up to the second order in the plane normal to the feeding direction.

采用二阶密切曲率法，即采用中凹的盘形铣刀取代传统的球头或鼓形铣刀，在每一行程中让刀具轴线相对于工件按特定的规律摆动，使得在垂直于进给方向的法截面中，由刀尖轨迹形成的包络面与理论曲面的法截线具有相同的1阶？

The influences of curvature, torsion and inclined angle of cross section of the pipe on the flow characteristics are analysed and studied in the fully developed steady laminar flow of helical square pipe.

借以分析研究了螺旋状矩形管在定常、充分发展的层流流动中，管的曲率、挠率和横截面倾斜角对流动特性的种种影响。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。