查询词典 planar developable surface

To compute the convex hull of a planar point set, first to find the extreme points of the planar point set and get the sub collections of points candidate for vertices of the convex hull between them.

新算法达到目前平面点集凸包问题的渐进最好算法的时间复杂度O，其中，n为平面点集的点数，h为平面点集凸包的顶点数。

Basing on the concepts and algorithms, some traditional algorithms, e.g. Delaunay triangulation for planar polygonal domain, constrained Delaunay triangulation for planar points and Delaunay tetrahedralization for spatial points, are improved.

通过上述概念和算法，改进了多边形Delaunay三角剖分、平面散乱点集约束Delaunay三角剖分和空间散乱点集Delaunay四面体剖分等基于生长算法的传统数据生成方法。

Planar waveguide is the primary component in Planar Optical System.

平面光波导是平面集成光学系统的基本元件。

In the last chapter, by introducing the isochronous center of real systems into complex planar and defining complex center and complex isochronous center, a concise linear recursion formula for period constants is given, necessary and sufficient conditions of complex isochronous center (the Time-Angle Difference Theorem) proved, conditions of real systems with linearizable center and saddle treated unitedly and the isochronous center conditions discussed fully for a class of real planar cubic systems.

在第七章，通过把实系统等时中心引入复平面研究，定义了复中心和复等时中心，给出了等时中心周期常数计算的简明的线性递推公式，证明了等时中心判定的充分必要条件，统一地处理了实系统具有可线性化的中心和鞍点条件，并对一类实平面三次系统的等时中心条件进行了完整研究。

Using staircase concatenation method SCM,the optimum coupling conditions were achieved for wedge-shaped fiber wedge angle,cylindrical endface lens curvature radius,semimajor axis of planar lightwave circuit elliptical field,aspect ratio of planar lightwave circuit elliptical field,misalignment tole.

在多量子阱-平面光波光路前置模斑转换器和不加模斑转换器的情况下，用阶梯串联法数值模拟并优化设计了楔形光纤-平面光波光路间最佳耦合参量：楔形光纤楔角45°、端面圆柱透镜曲率半径2。

In this paper, through an imaging system , the planar image of the inner sur- face of a pipe is obtained, and the judging creteria of analogy between object and image is given. Then, the geometric shapes of images of planar mirror ,conemirror ,off- axis spherical mirror are analysed in detail .

对管道内表面，通过成像系统在乎面上成像，给出其物像之间几何形状相似的判定标准，并对平面反射镜、圆锥反射镜和离轴球面反射镜在平面上成像的几何形状进行了详细的分析。

The design tool not only could provide various core specifications and its loss characteristic curves base on the core database, but also suit for PCB windings design of non-storage-energy type planar transformer with arbitrary number of winding and layer, and arbitrary connections. It is a good design tool for planar transformer with enough engineering precision, high performance and low cost.

软件不仅可以提供基于数据库的各种磁芯规格参数和各种损耗特性曲线，而且适用于分析、设计非储能式平面变压器的任意个线圈的任意连接结构和任意层数的PCB线圈，有足够高的工程精度，为设计高性能平面变压器提供了高性价比的设计工具。

These antennas can cover GSM900/DCS/PCS/UMTS operation. In the chapter 2, the antenna is designed based on the concept of monopole antenna. Furthermore, the antenna structure have two radiant paths and coupled each other at tail end to do impedance matching. In addition, to raise distance between radiation plane and ground will avoid capacitative effect effectually. In the chapter 3, the antenna is designed based on the concept of planar inverted-F antenna. Furthermore, that the antenna structure have two radiant paths and coupled each other at tail end to do impedance matching is similar to chapter 2. But there is a difference in them. We can choose the short position to change input impedance at this structure. In the chapter 4, the antenna is designed based on the concept of planar inverted-F antenna which takes coupled-fed. It will produce the first mode and high-order mode near the frequency, 900MHz. The feature of this type is to reduce the volume effectually. This antenna can not only cover GSM900/DCS/PCS/UMTS operation but maintain good radiation efficiency. Finally, we will compare three antennas, and develop procedure with industrial view, and propose the prospect of the GSM/GPRS antenna in PND, as a conclusion.

在第二章中，我们使用单极天线设计概念，使用双路径架构并於末端耦合来对天线阻抗做匹配，产生涵盖GSM900/DCS/PCS/UMTS四频操作频带，并提高与接地面的辐射高度，以避免电容效应，使天线具有良好的辐射特性；在第三章中，使用倒F形天线设计概念，使用双路径架构於末端耦合，并於辐射臂上采取适当接地点电感效应作输入阻抗匹配，达成涵盖GSM900/DCS/PCS/UMTS系统的四个操作频带；在第四章中，采用倒F形架构并使用耦合馈入方式，使得长辐射金属臂在低频900 MHz附近产生共振，产生低频基频模态及高阶模态，以达成宽频及频宽涵盖GSM900/DCS/PCS/UMTS频带操作，并有效缩减使用体积；最后，分别比较此三种架构的优缺点，再加以业界角度来思考，研发产品天线的流程及思考方向，以及天线应用於可携式导航装置中未来的展望作为本论文的总结。

The paper expounds the method of computer aided design for a conicograph acoording to the principle of the centrode for planar mechanism and the method of drawing the fixed centrode for planar mechanism with a "sliders dyad".

根据平面机构瞬心线的原理和利用加&双滑块二级组&绘制平面机构定瞬心线的方法，论述了一种圆锥曲线仪的计算机辅助设计方法，文中编制了程序设计框图，并通过实例绘制了圆锥曲线。

Our calculated results show that the relative stability of the isomers depends on the level of theory used: in the framework of DFT, Au10 trends to form planar structures, while the MP2 calculations show that the three-dimensional isomers are energetically more favorable. Based on the present results, Au10 may be conjecturably a critical species of gold clusters which bridges the planar structures and three-dimensional ones.

计算结果表明Au10团簇异构体的相对稳定性明显依赖所使用的理论方法和泛函，密度泛函结果显示Au10倾向于采用平面结构，且不同的泛函给出异构体的相对稳定性次序也不相同，而MP2计算则显示三维空间结构的Au10团簇更稳定， Au10可能是金团簇从二维结构到三维结构演化的一个临界点。

Fostering the concept of multi-culture firmly and mastering the development of advanced culture correctly are conductive to resisting terrorism, separatism of nationalities and ultraism of religion, which is of great academic theoretical, immediate and profound historical si...

牢固树立多元文化的理念和正确把握先进文化的发展方向，有助于在世界范围内自觉地抵制恐怖主义，民族分裂主义和宗教极端主义。不仅具有重大的学术理论意义，而且也具有重大的现实意义和深远的历史意义。

But if anyone walks in the night, he stumbles, because the light is not in him.

11：10 若在黑夜行走，就必碰跌，因为那光不在他里面。