三角

The result, once natural selection had done its work over the course of millions of years, was the now familiar cast of Allosaurus, Diplodocus, Triceratops and Tyrannosaurus rex.

自然界历时数百万年，完成了其优胜劣汰的工作，才得到如今这耳熟能详的演员阵容：异特龙、梁龙、三角龙和霸王龙。

This group, which includes such famous names as Stegosaurus and Triceratops, is one of the two clades into which the dinosaurs are divided. The other is the Saurischia, whose famous members include Diplodocus and Tyrannosaurus. The Saurischia also include all the immediate ancestors of birds.

按照当今考古界的分类法，恐龙被分为两大类，一类即鸟龙类，包括很有名的剑龙和三角恐龙；另一个则是蜥龙类，其中有很出名的梁龙和暴龙，同时蜥龙类中也有鸟类的直系祖先。

The intersection of sweep volume with complicated surface normal is transformed into computation of intersection between triangular mesh and directed line segment.

将扫描体与复杂曲面法矢的求交问题，转化为三角网格与有向线段之间的求交计算。

In this paper, a simple calculating method to establishthe interconversion between Eulerian angles and direction cosine by Spherical Trigonometry is presented.

为了从多个角度使用不同的手段研究旋转变换问题，本文提供了一种非常直观、简捷的计算方法，即利用"球面三角"的方法建立了用欧拉角与用方向余弦描述三维图形旋转变换的转换关系。

The reason why the model is based on Voronoi diagram and Delaunay triangulation is that one of the main factors of directional relationships is visible field of two objects, and the visible field is adjacent part of two object, so direction calculation of two objects may be limited in the adjacent field.

模型的建立之所以借助于Delaunay三角网和Voronoi图建立空间方向关系计算和描述模型，是因为决定两目标之间的空间方向关系的主要因素之一是这两个目标之间的可视区域，而可视区域恰好是它们的邻近区域，因而两目标的空间方向计算问题可以归结为目标间邻近区域内的问题。

This new genus is rather similar to Hemeroscopus Pritykina,1977, but differs from the latter in the following characters:(1) hindwing anal loop is smaller, only with 6-7 cells;(2) Rspl is absent;(3) the hindwing vein CuAa is curved and has five distinct posterior branches;(4) the forewing MP is not shortened, reaching the posterior wing margin slightly beyond the level of the nodus;(5) pterostigmata more distinctly braced;(6) the hindwing area between MP and CuAa is narrow, with only one row of cells near the discoidal triangle.

新属与巴依萨昼蜓HemeroscopusPritykina，1977在形态上比较相似，但在演化程度上更为原始，主要体现在下面几个方面：(1)后翅臀套较小，仅有 6～ 7个翅室；(2 )径增脉缺；(3)后翅CuAa脉弯曲，带有 5个明显的后分支；(4 )前翅MP脉不显短，终止于翅后缘近翅结处；(5 )翅痣下有一个明显的支脉；(6 )后翅CuAa和MP域基部较窄，在三角室下方仅有 1排翅室。

The main objective of this dissertation was to develop methodologies with capability of engineering application for simulating flow in fractured rock using discontinuum models. The study work includes three parts. In the first part, numerical methodology of three-dimensional discrete fracture network model casing on hybrid BEM-channel was presented, and the technique for improve the model's computing efficiency was also studied. Firstly in this part, computer simulation methodology based on the Baechermodel for generating network of discrete fractures was presented, which includes the follow details: probability distributions of fracture density,orientation, trace length, size, and aperture and estimation of their statistical parameters; stochastic models of fracture network; Monte-Carlo's simulation method; numerical simulation procedure and technicality.

给出了离散裂隙网络模型所依据的基本假定；发展了基于Baecher模型的离散裂隙网络计算机随机生成技术：详细地推导了单裂隙渗流和多裂隙相交网络渗流的边界单元法公式，发展了离散裂隙网络中稳态渗流的边界元数值技术，并且讨论了相关的具体数值技术细节，如角点的处理方法，单元的自动剖分等：描述了混合边界元—管流模拟方法及其数值实现；研究了裂隙网络的简化方法，并针对裂隙网络边界元法的特点提出了一种改进的分块三角分解法。

ABSTRACT In this dissertation, the architecture of the robot model machining system is introduced, and the surface reconstruction, triangulating the discrete surface, process planning and path planning in the machining system is deeply and systematically investigated.

本论文对机器人模型加工系统的组成结构、模型加工中的曲面重建、空间离散点曲面的三角划分以及模型加工的工艺规划和路径规划等方面，进行了系统、深入的研究。

The Retail market in the Yangtze Delta enjoys a comparatively high degree of development, which, however, is disproportional among different cities within the area.

长三角地区零售业的成熟度较高，但城市之间的发展不均衡，整体而言还有较大的发展潜力。

Spatial relationship; Polygon; Delaunay triangular net; Closest distance; Restricted circle

空间关系；多边形；Delaunay三角网；最近距离；约束圆

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。