A new method of extracting the altitude curves along chromosomes based on contour line

Author(s):  
Fengtian Li ◽  
Li Ma ◽  
Bo Liu ◽  
Ruihua Chen ◽  
Changhai Ru
Keyword(s):  
2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Defu Che ◽  
Zonghui Li ◽  
Yining Liu ◽  
Renqing Zhong ◽  
Baodong Ma

Operating and managing single three-dimensional building model individually are critical in the application of oblique photography models. However, these models are usually complete and continuous, and the single three-dimensional building model in these models cannot be managed individually. Generally, achieving a single three-dimensional building model requires a human-computer interaction to determine the cutting range, but this process is time-consuming and inefficient. To overcome this problem, this study proposed a new method for automatically achieving single three-dimensional building model without the need for human-computer interaction. First, the point clouds of an oblique photography model are divided into virtual grids, and the point clouds in each virtual grid are seen as a whole. In this way, the number of point clouds involved in the calculation is reduced, thereby improving computing efficiency. Second, the point clouds of a building facade are extracted by setting the height difference. By comparing the height difference between the highest point and the lowest point of the grid with height difference threshold, all point clouds in the grid that do not meet the requirements are eliminated. Third, the point clouds of the building facade are classified, and the contour line is extracted by the classified point clouds. Finally, the single three-dimensional building model is achieved by reconstructing the triangles that intersect with the extracted contour line. Experimental results show that the proposed method can effectively achieve single bodies automatically from an oblique photography building model. This method is then useful for achieving single three-dimensional building model from massive oblique photography data.


Author(s):  
C. C. Clawson ◽  
L. W. Anderson ◽  
R. A. Good

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.


1960 ◽  
Vol 23 ◽  
pp. 227-232 ◽  
Author(s):  
P WEST ◽  
G LYLES
Keyword(s):  

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