对称房屋

In topographic map, especially for city area, most of features are central symmetry and axial symmetry. By means of extracting features with symmetric figure first and then vectoring them according to their geometric characteristic, accuracy and efficiency can be increased and data sizes can be reduced.

在地形图中，轴对称和中心对称的要素占据着相当大的比例，特别是城市地形图中，房屋建筑等具有对称形状的要素占据了地形图中要素的绝大部分，在扫描图中首先对这些要素进行提取，进而根据特定要素的几何特征矢量化，可显著地提高矢量化精度和效率，减少数据的储存量。

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。