查询词典 developable surface

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。

There are series of papers studying the solvability of an incompressible, viscous, instationary fluid contained in a domian bounded entirely by a free surface. In 1977, Solonnikov proved its local solvability in a Holder space for any initial date but without surface tension. In 1984, he considered the same problem in a Sobolev space with surface tension being taken into account. In I992, Mogilevskii and Solonnikov treated the same problem in a Holder space, where the coefficient of surface tension is not a constant. There are also short-time existence results for the solvability of an incompressible, vicous, unsteady fluid bounded above by a free surface and below by a fixed bottom which approach horizontal planes at infinity. In 1981, Beale proved its local solvability in a Sobolev space for any initial date but without surface tension. In 1983, Allain were concerned with the same problem in R〓 with surface tension but under the assumption that the initial fluid domain was near a horizontal strip. In 1987, he obtained the same result without the preceding assumption. In 1996, Tani solved the same problem in R with surface tension. For the solvability of an incompressible viscous instationary fluid in Ω R bounded inside by a free surface S and outside by a rotating boundary S, in 1995 Ciuperca proved its local existence in a Sobolev space for any initial date but without surface tension. In this paper, we consider the same problem with surface tension.

对于边界完全是由自由边界组成的有界区域中粘性不可压流体的非定常运动问题，Solonnikcv于1977年在忽略表面张力情况下证明了初值问题小时间解在Holder空间的存在性，于1984年在有表面张力情况下证明了初值问题问题小时间解在Sobolev空间的存在性，Mogilevskii和Solonnikov于1992年在表面张力系数可以不是常数情况下证明了初值问题小时间解在Holder空间的存在性；对于上面是自由边界、下面是固定边界且两边界在无限处趋于水平的无限区域中粘性不可压流体的非定常运动问题，Beale于1981年在忽略表面张力情况下证明了初值问题小时间解在Sobolev空间的存在性，Allain于1983年在有表面张力情况下证明了R中初值问题小时间解在Sobolev空间的存在性，但其中假定初始区域近似是个水平条，他于1987年去掉了这个假定得到同样的结果，Tani于1996年在有表面张力情况下证明了R中初值问题小时间解在Sobolev空间的存在性；对于R中内面是自由边界、外面是旋转边界S的有界区域中粘性不可压流体的非定常运动问题，Ciuperca于1995年在忽略表面张力情况下证明了初值问题小时间解在Sobolev空间的存在性，本文考虑了在有表面张力情况下初值问题可解性问题。

In the research of techniques in curved surface reconstruction and feature extraction, the modeling of NURBS interplation curved surface based on rectangular is focused, in which centripetal parameter is applied to construct node vector, the application of interplation method guarantees the accuracy of curved surface construction, bicubic NURBS curved surface is taken as an example to demonstrate the process of curved surface modeling, and the effectiveness of NURBS is approved in application; Meanwhile, the application of feature techniques in reverse engineering is also diSCUSSed, the recognition and extraction method of feature curved surface are investigated, the relationship between feature recognition and the curvature of curved surface is discussed, with the application of linear and non-linear least squares procedure, data fitting of conicoid in ball surface, cylinder surface and cone surface is

以上述的研究工作为基础，根据企业的实际需求选定轻客和重卡作为研究对象完成了基于反求工程的车身改型设计和优化的工程实践，通过工程实践对反求工程各关键支撑技术进行了验证，所开发的新车型也获得了良好的市场反应。

Results 1、 Generally, we can see the original blue and white, shiny, no cracks in the articular surface of the cartilage after the stress increases gradually yellow, surface roughness, cracks appear; when the pressure decreases, the yellowing, rough, the color of the fracture restore gradually and become shiny.2、the shiny smooth surface can be seen under a light microscope, formation, cell distribution, tidy, clear the level of cartilage at the articular surface stress increases, the surface roughness changes, defects, disordered cells, uneven dyeing ; when the articular surface of the pressure gradually decreased, the cartilage gradually repair and the surface of cells at the surface appear only disorder.3、immunohistochemical observation can be seen throughout the observation period, cartilage cells are type Ⅱ collagen expression and expression after 3 weeks gradually weakening, when the seventh week begin to strong gradually.4、 electron microscopy shows that when stress increases the articular surface, the cartilage cells became flat, the cytoplasm in the endoplasmic reticulum, Golgi apparatus decreased with collagen disorders; and when stress decreases the articular surface, cartilage cells gradually returned normal, cytoplasm in the endoplasmic reticulum, Golgi body gradually restore quantity; collagen fibers with a gradual rules.

结果：①大体观察可见到原本蓝白色、有光泽、无裂纹的软骨在关节面压力增大后，逐渐呈灰黄色，表面粗糙，出现裂隙；当压力逐渐减小后，变黄、粗糙、有裂隙的软骨颜色逐渐恢复，变得有光泽②光镜下可见表面光滑、平整，细胞分布均匀、整齐，层次清楚的软骨在关节面压力增大后，表面变粗糙、缺损，细胞排列紊乱、染色不均；当关节面压力逐渐减小后，软骨表面逐渐修复，细胞仅在表层排列紊乱③免疫组织化学观察可见整个观察期内软骨细胞胞浆内均有Ⅱ型胶原表达，术后3周内表达逐渐变弱，从第7周时开始逐渐变强。④电镜下可见当关节面压力增大后，软骨细胞逐渐变扁，胞质中内质网膜、高尔基体减少，胶原排列紊乱；当关节面压力减小，软骨细胞形态逐渐恢复正常，胞质中内质网膜、高尔基体数量逐渐恢复；胶原纤维排列逐渐有规则。

This paper on basis of surface's local principle.Through discussing the Gauss mipping image of the surface's asymptotic curve and the camber between any two directions of surface and the developable surface to illustrate the impact on surface of Gauss mipping.

文章以局部曲面的基本理论为基础，通过对曲面的渐近曲线、曲面上任意两方向的夹角和可展曲面的高斯映射象的讨论来说明高斯映射对曲面的影响。

To solve the problems in adjusting and controlling shapes of developable surfaces, following the important idea of duality between points and planes in 3D projective space, two direct explicit and efficient methods of computer aided design for developable surfaces are proposed.

为了解决工程中可展曲面位置与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2种直接、简单有效的可展曲面设计新方法。

By means of moving frame, some properties of ruled surfaces are obtained, including the surfaces being minimal, totally geodesic, totally developableand totally umbilical. Some equivalent conditions in which the ruled surfaces are totally developable are obtained. It is abtained that (k+1)-dimensional ruled surfaces are totally geodesic if and only if they are minimal and totally developable.

利用活动标架法研究了直纹面的一些性质，包括极小性，全可展性，全测地性和全脐性，给出了直纹面是全可展性的一组充要条件，同时得到，R(上标 n+1 下标 v)中的k+1维直纹面M是全测地的充要条件是它是极小的且全可展的。

The major content of this course includes: calculation, measurement and control of solid surface composition, the structure of solid surface, electronic potential, energy band structure and surface energy state of solid, the action between gas and solid surface, chemistry behaviors of molecular on solid surface (chemisorption and catalysis of solid surface), activation and passivation of solid surface, fundamental principle and application of photo and electricity surface reaction, design of solid surface functional materials, and etc.

基本内容包括：固体表面组成计算、测定与调控，固体表面结构表示方法、测定与控制，固体表面电子势和表面态、固体表面能带结构以及固体能带的测定，固体表面的功能、气体-固体表面间的作用以及气体-固体表面作用的研究方法，分子在固体表面上的化学行为(化学吸附和固体表面催化作用)，固体表面的活化与钝化，光电表面化学反应基本原理及应用，固体表面功能材料的设计等领域。

Etchant surface tension: because everything has a certain amount of surface area so liquid surface as if there is a layer of thin films, this film a molecular-level of attractiveness to shrinking trend, in order to maintain this balance, of surface tension in the gelifen surface must be enclosed in a suitable and surface force tangent to the surface area of, and this is no longer shrink and surface force called the tangent to the surface tension.

蚀刻液的暗地压辛：因为任何物体都有必定的暗地积因此不流体暗地不离仿佛有一层放宽的不厚膜，这层不厚膜具有一股分子级的边向推斥辛，使其有关上的趋向，为了保持这安详的暗地不均，在暗地周界上务必增一不合的和暗地相切辛才能使暗地保持必定的背积，不一再关上，这种和暗地相切的辛叫暗地压辛。

Single factor experiments were done with the factors including the width of protrusion and the trolley's velocity, which showed that the surface frictional coefficient decreases with the width of protrusion increasing, and doesn't change with the trolley's velocity changing, which was consistent with the results of the orthogonal experiment. A theoretical model of the horizontal projection of a corrugated bionic surface's contact area was built, which showed that the contact area's horizontal projection decreases with width and interval increasing respectively and that the ratio of the contact area's horizontal projection and the vertical load decreases with the vertical load increasing. It indicated that the surface frictional coefficient decreases with the above three factors increasing respectively. Finite element modeling and analysis of interactions of a plate and soils was done using ANSYS, which showed that the plate frictional coefficient is little relative to soil elastic modulus and decreases with vertical surface pressure and that trolley's pull and vertical displacement of bionic surface's control pilot keep constant almost during the plate being pulled. Finite element modeling and analysis of interactions of a corrugated bionic surface and soils was done using ANSYS, which showed that surface frictional coefficient is little relative to soil elastic modulus and decreases with bionic surface's structural parameters and vertical pressure increasing. However, the three factors all didn't affect the surface frictional coefficient remarkably on the condition of 90% dependability. For the first time, bionic surfaces were applied to screw piles, which formed bionic screw piles, and the contrast experiments showed the bionic screw pile had certain resistance-decreasing effects.

建立了波纹型仿生曲面与土壤的接触面积的水平投影的理论模型，表明接触面积的水平投影A随着波纹型仿生曲面突起宽度、两相邻突起间距的增大而减小，接触面积的水平投影与波纹型仿生曲面表面垂直载荷之比随着波纹型仿生曲面表面垂直载荷的增大而减小，进而得出仿生曲面摩擦系数随着波纹型仿生曲面突起宽度、两相邻突起间距以及表面垂直载荷的增大而减小；利用ANSYS软件对平板与土壤的相互作用进行了有限元建模与分析，表明平板摩擦系数与土壤弹性模量关系不大，而随着表面垂直载荷的增大而减小；平板牵引过程中台车牵引力和仿生曲面控制节点垂直方向位移基本保持不变；利用ANSYS软件对波纹型仿生曲面与土壤的相互作用进行了有限元建模与分析，表明波纹型仿生曲面系数在一定范围内基本不受土壤弹性模量的影响，随着波纹型仿生曲面突起宽度、两相邻突起间距以及表面垂直载荷的增大而减小，但在可信度为90％的前提下，三个因素影响都不显著；首次将波纹型仿生曲面应用于与土壤作用方式以挤压为主的螺旋桩，形成仿生螺旋桩，并与普通螺旋桩进行了沉桩对比试验，表明波纹型仿生曲面应用于螺旋桩桩体表面具有明显的降阻作用。

Researches reveal that students who suffer from corporal punishment tend to resort to violence in their future life.

研究表明遭受过肉体惩罚的孩子倾向于在他们今后的人生中使用暴力。

Total sugar of sarcocarp and chlorophyll of pericarp increased firstly, and then decreased afterward along with altitude; Titratable acidity, ascorbicacid and anthocyanin of pericarp were increased along with altitude; The content of protein increased firstly and decreased afterward along with altitude; Carotenoid of pericarp were decreased along with altitude.

果肉总糖和果皮叶绿素含量随海拔高度升高先升高后降低；可滴定酸、维生素C和果皮花青苷含量均随海拔升高而升高；蛋白质在1720m处最大，1420m处最小；果皮类胡萝卜素随海拔升高而降低。