查询词典 developable

The paper deals with curvature line and curvature characteristic of developable surface based on differential invariant of developable surface and it details curvature line and curvature characteristic of cone and tangent surface .

本文通过可展曲面的微分不变量，导出可展面的曲率线与曲率特征，并以锥面和切线曲面为例阐明这些特性的几何意义。

Furthermore,we present the method for designing quadratic Bezier developable surface:give four corner points of developable surface and two free designing parameters,the other two control vertexes are on the line connecting the linear interpolation point between the first two control vertexes and the linear interpolation point between the last two control vertexes,and they are the linear interpolation points between these two linear interpolation points respectively,namely,these four linear interpolation points are colinear.

提出了二次Bézier可展曲面的设计方法：给定可展曲面的4个角点a0、b0、a2、b2和两个自由设计参数？姿、？滋，则待求的2个控制顶点a1、b1是在前2个控制顶点a0、b0的线性插值点a*与后2个控制顶点a2、b2的线性插值点b*的连线上，并且也是a*、b*这2个线性插值点的线性插值，即这4点a*、a1、b1、b*共线。

This method presented in this paper can save a lot of time in drawing the developable surface, increase the productive efficiency and the accuracy of blanking , and can be applied to all dinds of expansion of developable surface, zoom the dimension.

该方法可大大缩短可展曲面展开图的绘制时间，提高生产效率及展开下料精度，适用于各种类型可展曲面的展开，并可进行尺寸缩放等相关操作，具有较好的实用性和经济价值

Furthermore, by the design method that a developable surface is an envelope surface, we give detail analysis of examples about using the same control planes to design developable surfaces.

讨论了所设计可展曲面的特点和几何构造，研究结果表明，所提出的设计方法具有现有曲线设计方法的特征，现有的对于曲线的一些几何构造技术可延伸到可展曲面的设计。

The given geometric model of garment basic pattern surface is composed of the integrally smooth and continue developable surface, which breakthroughs traditional model of intersected joining by a lot of little developable surface.

所给出的服装原型曲面的几何模型由整体上光滑连续的组合式可展面构成，突破了用小块可展面相交拼接的传统模式，更加符合服装设计的要求，具有良好的可操作性。

Based on the important idea of duality between plane and point geometries,two direct explicit methods of computer-aided design for developable surface s were proposed,the developable surface s were represented using control planes with appropriate basis functions.

为了克服传统方法在可展曲面设计上的缺陷，方便地解决工程中经常遇到的可展曲面位置和形状难以调整和控制的问题，基于3D射影空间中点和平面间的对偶性这一重要思想，提出了两种直接、简单的可展曲面设计方法。

It order to overcome the difficulties in representation of developable surface s utilizing traditional approaches,based the concept of duality between points and planes in 3D projective space, a direct explicit method of computer-aided design for developable surface s was presented.

基于三维射影空间中点和平面间的对偶性，提出了计算机辅助设计五次样条上可展曲面的一种简单且有效的方法，通过采用该方法，可利用具有B啨zier和B样条基的控制平面设计可展曲面。

We proved that the necessary and sufficient condition that the developable surfaces touch the second focal surface along the orthogonal trajectories was that the base surface S was a developable surface.

证明了线汇中的两系可展曲面交第二叶焦曲面于正交轨线族的充要条件是原曲面是可展曲面，并给出了两叶焦曲面在同一条光线上两焦点相互对应下，保持渐近曲线相互对应的充要条件。

In the particular ease where a and γ are equal to 1, the developable CE-Bézier surface is a developable Bézier surface. Finally, some applications in developable surfaces design are discussed, The modeling examples illustrate that the developable CE-Bézier surfaces provide two valuable ways for the design of developable surfaces.

由新方法生成的可展曲面不仅具有灵活的局部形状可调性和更强的描述能力，而且保留了CE-Bézier曲面的特性，特别是当α、γ都取值为1时，所生成的可展曲面即为CE-Bézier可展曲面。2种可展曲面设计方法的应用实例表明，该设计方法不仅简单、有效，而且易于控制曲面形状，从而为可展曲面的设计提供了一种新途径。

By the definition of Darboux type vector and rectifying Darboux type vector ,we constructed the rectifying type developable surfaces and Darboux type developable surfaces and tangential Darboux type developable surfaces ,and study these three developable surfaces relationship with Minkowski slant helices and Minkowski conical geodesic curves. Bying applying the singularity theoerical knowledge, We give a classification of special developable surfaces under the condition of the existence of such a special curve as geodesic.

通过定义三维Minkowski空间中的达布型向量以及修正达布型向量，构造出三维Minkowski空间中的三类可展曲面，即修正型可展曲面、达布型可展曲面和切达布型可展曲面，研究Minkowski斜螺线和Minkowski锥面测地线这两种特殊曲线和这些曲面的关系，并研究Minkowski斜螺线和Minkowski锥面测地线作为这些曲面的测地线的条件下，运用奇点理论的知识，对这三种可展曲面进行奇点分类。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。