摘要
近年来,基于位置的服务获得了越来越广泛的关注,其中最近邻查询是最常用的一种查询方式.测量手段的不准确性以及数据本身的性质导致不确定性在位置数据中普遍存在,这种不确定性会对最近邻查询结果产生影响.空间中障碍物的存在也给空间数据查询带来了挑战.文中研究存在障碍物的空间中不确定对象连续最近邻查询的处理方法,设计了一种剪枝策略大幅降低需要计算的不确定对象数目,并进一步提出了障碍空间中不确定对象最近邻查询安全区域的概念及安全区域生成算法.设计了安全区域的索引存储方法.实验结果表明,文章所提出的方法具有良好的效率和可扩展性.
In recent years,location-based services（LBS） are getting more and more attention.The nearest neighbor query is the most common query type in the LBS area.The uncertainty of data exists commonly due to the inaccuracy of measurement instructions and the data attributes itself.This uncertainty will affect the results of nearest neighbor queries.The existence of obstacles in planes also put challenges to spatial data queries.This paper studies the continuous nearest neighbor query by the existence of obstacles and the uncertainty of data.It also gives a pruning strategy that greatly reducs the number of objects which need to be calculated.Furthermore,this paper proposes the safe region concept with regard to uncertain data in obstructed spaces,an algorithm to generate the safe regions,and an indexing method for saving safe regions.Experimental results show that the proposed method has good efficiency and scalability.
出处
《计算机学报》
EI
CSCD
北大核心
2010年第8期1359-1368,共10页
Chinese Journal of Computers
基金
国家自然科学基金(60773220
60933001)
国家"八六三"高技术研究发展计划"高效的纯XML数据管理关键技术研究及原型系统实现"(2009AA01Z131)资助~~
关键词
最近邻
不确定
障碍空间
基于位置的服务
nearest neighbor
uncertain
obstructed space
location-based services
