查询词典 Delaunay

Compared with traditional DEM or TIN based methods, this pure vector approach obtains not only the topological structure of drainage system in planar graph, but also the valley distribution polygon range. Depending on geometrical computation and judgment of vector line, polygon, the structured properties in drainage representation is enhanced, avoiding the case of noise disturbance in DEM based method. The core algorithm makes use of the ability of Delaunay triangulation in detecting hierarchical structure of each contour line.

中文摘要：基于Delaunay三角网模型在矢量等高线基础上通过弯曲特征分析，给出了一种地形结构特征提取及谷地树组织的方法，与传统的基于DEM或TIN数据结构提取地形特征的方法相比，该方法不仅得到了谷地系统在平面图上的拓扑结构，还获得了河谷在空间分布上的汇水范围，依托矢量线、多边形的几何关系判断，增强了谷地树组织中的结构化，避免了DEM方法中的噪音干扰，方法的核心是Delaunay三角网在单根等高线弯曲深度表达上的层次结构识别。

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。

A new triangulation algorithm based on Delaunay triangulation and the advantage of simplicity and rapidness of advancing front method is constructed.

将推进波前法的实现简单和快速的特性引入到Delaunay三角剖分法之中，构建一种基于Delaunay三角剖分的算法。

Delaunay triangulation has been used to partition the selected extrema, then replaces the pixels that not contained in the Delaunay polygon through symmetry principle, which can restrain the variance phenomenon that appeared in the cubic spline interpolation.

利用Delaunay三角剖分方法对选取的极值点进行分划，对不包含在Delaunay多边形内的边界像素采用对称处理，抑制了3次样条插值过程中边界点变异现象。

Edges are first detected in the original image and then cut equidistantly into some segmentations, and the end points of segmentations are gathered into a points set. A constrained Delaunay triangulation is yielded from the points set and then a graph is attained too.

首先提取图像边缘，然后将边缘分段切割，得到端点集合，然后从端点集合生成Delaunay三角形网络，以Delaunay三角形为顶点，相邻三角形的属性差异作为边的权重，构造图；以基于图的分割算法生成最小生成树，划分区域。

Because Delaunay triangle is nearly equilateral triangle, modeling reseau with the method of Delaunay will be relatively well-proportioned. The whole image will looks shapely, not snatchy and inaccurate.

使用Delaunay方法来建模，由于Delaunay三角是尽量接近于等边三角形的，所以用这种方法建的网格会比较均匀，显示图像的时候视觉效果就是整个图像很匀称，不会出现粗细不均或者漏洞百出的情况。

Because Delaunay triangle is nearly equilateral triangle, modeling reseau with the method of Delaunay will be relatively well-proportioned. The whole image will looks shapely, not snatchy and inaccurate.

使用Delaunay方法来建模，由于Delaunay3角是尽量接近于等边3角形的，所以用这种方法建的网格会比较均匀，显示图像的时候视觉效果就是整个图像很匀称，不会出现粗细不均或者漏洞百出的情况。

The paper applies Delaunay triangulation to branching problem according to characteristics of the Delaunay triangula- tion of constrained edge point sets,moreover,mends and implements a branching problem algorithm.

根据平面点集Delaunay三角剖分的特性，将Delaunay三角剖分应用到分支问题上，改进和实现了一种分支问题处理算法。

Two ways to measure stability of tetrahedrons will be introduced. An earlier method to improve tetrahedron stability, the Snap Method, will be briefly discussed. Then techniques used in Delaunay. triangulation to deal with degenerated elements will bethoroughly investigated.

本文引入了两种单元质量的描述方法，简单介绍了已有的提高四面体稳定性方法之一—投射法；然后介绍了Delaunay方法中使用较广泛的逐点插入法的核心思想，将Delaunay网格构造法中处理退化单元的方法；删除法和换面法，改造后应用于四面体稳定性的提高上。

This method can effectively reduce the numbers of artificial dams and local minima.The algorithm has been implemented in five different terrains,showing that the method can effectively reduce the numbers of the local minima.So,it is more realistic for generating terrains model with higher order Delaunay triangulations.

实验结果表明，高阶Delaunay三角网能够有效地减少地形中局部极小的数量，因此，采用高阶Delaunay三角网建立的地形模型更接近于实际地形。

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。