Uniform quotient mappings of the plane with non-discrete point inverses

2001 ◽  
Vol 124 (1) ◽  
pp. 203-213
Author(s):  
Aicke Hinrichs
Keyword(s):  
Discrete Point ◽  
Quotient Mappings

An Efficient Improved Algorithm of Convex Hull

2014 ◽  
Vol 602-605 ◽  
pp. 3104-3106
Author(s):  
Shao Hua Liu ◽  
Jia Hua Zhang
Keyword(s):  
Convex Hull ◽  
Line Segment ◽  
Main Idea ◽  
Discrete Point ◽  
Directed Line ◽  
Generation Algorithm ◽  
Simple Program ◽  
Point Set ◽  
High Computational Efficiency ◽  
Improved Algorithm

This paper introduced points and directed line segment relation judgment method, the characteristics of generation and Graham method using the original convex hull generation algorithm of convex hull discrete points of the convex hull, an improved algorithm for planar discrete point set is proposed. The main idea is to use quadrilateral to divide planar discrete point set into five blocks, and then by judgment in addition to the four district quadrilateral internally within the point is in a convex edge. The result shows that the method is relatively simple program, high computational efficiency.

A New Stretch-Forming Process Based on Loading at Discrete Points and its Numerical Investigation

2013 ◽  
Vol 423-426 ◽  
pp. 737-740
Author(s):  
Zhong Yi Cai ◽  
Mi Wang ◽  
Chao Jie Che
Keyword(s):  
Sheet Metal ◽  
Three Dimensional ◽  
Discrete Point ◽  
Stretch Forming ◽  
Sheet Metal Part ◽  
Metal Part ◽  
Forming Process ◽  
Loading Trajectory ◽  
New Process ◽  
Forming Defects

A new stretch-forming process based on discretely loading for three-dimensional sheet metal part is proposed and numerically investigated. The gripping jaw in traditional stretch-forming process is replaced by the discrete array of loading units, and the stretching load is applied at discrete points on the two ends of sheet metal. By controlling the loading trajectory at the each discrete point, an optimal stretch-forming process can be realized. The numerical results on the new stretch-forming process of a saddle-shaped sheet metal part show that the distribution of the deformation on the formed surface of new process is more uniform than that of traditional stretch-forming, and the forming defects can be avoided and better forming quality will be obtained.

Prediction of Red Light Running Based on Statistics of Discrete Point Sensors

2009 ◽  
Vol 2128 (1) ◽  
pp. 132-142 ◽  
Author(s):  
Liping Zhang ◽  
Kun Zhou ◽  
Wei-bin Zhang ◽  
James A. Misener
Keyword(s):  
Red Light ◽  
Discrete Point ◽  
Red Light Running

scholarly journals Grid Partition Variable Step Alpha Shapes Algorithm

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Zhenxiu Liao ◽  
Jun Liu ◽  
Guodong Shi ◽  
Junxia Meng
Keyword(s):  
Average Distance ◽  
Discrete Point ◽  
Boundary Extraction ◽  
Grid Partition ◽  
Alpha Shapes ◽  
Extraction Algorithm ◽  
Variable Step ◽  
Point Set ◽  
Index Table ◽  
Previous Step

On the basis of Alpha Shapes boundary extraction algorithm for discrete point set, a grid partition variable step Alpha Shapes algorithm is proposed to deal with the shortcomings of the original Alpha Shapes algorithm in the processing of nonuniform distributed point set and multiconcave point set. Firstly, the grid partition and row-column index table are established for the point set, and the point set of boundary grid partition is quickly extracted. Then, the average distance of the k -nearest neighbors of the point is calculated as the value of α . For the point set of boundary grid partition extracted in the previous step, Alpha Shapes algorithm is used to quickly construct the point set boundary. The proposed algorithm is verified by experiments of simulated point set and measured point set, and it has high execution efficiency. Compared with similar algorithms, the larger the number of point sets is, the more obvious the execution efficiency is.

Sign in / Sign up

Export Citation Format

Share Document