路网中空间关键字连续k近邻查询算法研究  

Processing continuous top-k spatial keyword queries over road networks

作　　者：李艳红[1] 李国徽[2] 张聪[3] 

机构地区：[1]中南民族大学计算机科学学院,湖北武汉430074 [2]华中科技大学计算机科学与技术学院,湖北武汉430074 [3]武汉工业学院数学与计算机学院,湖北武汉430023

出　　处：《华中科技大学学报（自然科学版）》2013年第12期54-58,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(61309002);湖北省自然科学基金资助项目(2012FFB07401)

摘　　要：研究了路网中空间关键字连续k近邻查询问题(CkSKQ),提出了包含一棵PMR-quad树和三个内存表的数据结构以存储和索引路网结构信息、对象的位置和关键字信息.空间关键字查询综合了查询点和待查询对象间的路网距离和关键字相似程度两个因素,提出了可调节的综合距离值计算公式,以满足各种具体应用对关键字相似度和路网距离不同的侧重程度.为了实现查询的连续处理,通过监控有关候选对象的综合距离值的变化来对查询结果进行修正,以保证查询结果的持续有效性.实验验证表明所提出算法的性能明显优于对照算法.The aim of this paper is to address processing continuous top-k spatial keyword queries （CkSKQ） over road networks. Firstly, an efficient data structure consisting of a PMR-Quad tree and three in-memory tables was proposed to keep and index the information of road network structure, the positions and keywords of data objects. Since the spatial keyword query has both considered the road network distance and the keyword similarity of the query point and objects being searched, an adjusta- ble synthetic distance calculation formula was presented to meet the requirement of various specific ap- plicationsr preference for these two parameters. To continuously process the CkSKQ queries, the pro- posed method monitors the synthetic distances of candidate objects and amends the query result so as to ensure the continuous effectiveness of query result. Finally, the performance of the method was tested by the simulation experiment. The experimental results show that this method is obviously more efficient than the compared method.

关 键 词：空间关键字查询 K近邻查询 路网 连续监控 算法 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]