顾及空间邻接关系的多级河流线状矢量数据并行压缩算法  

A Parallel Compression Algorithm for Multilevel River Linear Vector Data Considering Spatial Adjacency Relations

作　　者：朱晓波[1,2] 周廷刚[1,2] 曾波[1,3] 沈敬伟[1,2] 潘勇卓 丁彤彤[2] ZHU Xiao-bo ZHOU Ting-gang ZENG Bo SHEN Jing-wei PAN Yong-zhuo DING Tong-tong(Key Laboratory of Eco-Environments in Three Gorges Reservoir Region （Ministry of Education）, Chongqing 400715, China School of Geographical Sciences, Southwest University, Chongqing 400715 , China School of Life Sciences, Southwest University, Chongqing 400715, China)

机构地区：[1]三峡库区生态环境教育部重点实验室,重庆400715 [2]西南大学地理科学学院,重庆400715 [3]西南大学生命科学学院,重庆400715

出　　处：《西南大学学报（自然科学版）》2017年第2期100-106,共7页Journal of Southwest University(Natural Science Edition)

基　　金：三峡后续工作库区生态与生物多样性保护专项项目(5000002013BB5200002);国家自然科学基金项目(41301417);重庆市基础与前沿计划(cstc2014jcyjA20017)

摘　　要：提出了一种顾及空间邻接关系的多级河流线状矢量数据并行压缩算法.首先利用拓扑分析和网络分析提取多级河流矢量数据的空间邻接结点,并对Douglas-Peucker算法进行改进;然后基于数据并行的任务分配方式,设计多级河流矢量数据并行压缩算法,并利用消息传递接口和C语言对该算法进行编程实现;最后设计验证性实验,利用该算法对三峡库区重庆段的多级河流矢量数据进行压缩.研究表明:利用该算法压缩多级河流矢量数据的空间邻接结点保持率达到100%,同时相对于串行算法,计算节点为4时平均加速比可达2.507,提高了压缩效率.This paper proposes a parallel compression algorithm for multilevel river vector data considering spatial adjacency relations.The algorithm is composed of several steps.Firstly,in order to keep the spatial adjacency relations of multilevel rivers,the spatial adjacency nodes of multilevel river vector data are extracted by topology analysis and network analysis.Then the Douglas-Peucker algorithm is improved to keep these spatial adjacency nodes in the process of compression.In this way,a serial compression algorithm for multilevel river vector data is proposed.Next,on the basis of establishing the task allocation method and communication method,this paper proposes a parallel compression algorithm for multilevel river vector data,and the algorithm is implemented using message passing interface（MPI）and C programming language.Finally,the parallel compression algorithm is applied to compress the vector data of multilevel rivers in the Three Gorges Reservoir Area of Chongqing.The results show that the spatial adjacency nodes retention rate of multilevel river vector data can reach an average of 100% using the proposed parallel compression algorithm.Meanwhile,the speed-up ratio can reach an average of 2.507 with 4compute nodes using the parallel compression algorithm comparing with serial compression algorithm,the compression efficiency of multilevel river vector data is improved.

关 键 词：多级河流 空间邻接关系 矢量数据压缩 DOUGLAS-PEUCKER算法 并行计算 

分 类 号：P208[天文地球—地图制图学与地理信息工程]