摘要
针对TPR*-tree隐含移动对象部分最近历史信息但不能提供历史信息查询的问题,将移动对象创建或更新时间引入到索引树中,提出一种既支持预测查询又支持部分历史信息查询的索引树Basic HTPR*-tree,为全时态查询奠定了坚实的基础.同时,为了支持移动对象的频繁更新,在Basic HTPR*-tree索引树基础上引入内存概要结构和Hash辅助索引结构,提出支持自底向上更新策略的HTPR*-tree索引结构.实验结果表明,HTPR*-tree更新性能优于TPR*-tree和Basic HTPR*-tree(TD_HTPR*-tree),预测查询性能仅仅稍逊于TPR*-tree.
In the TPR ＊ -tree, the partial history trajectory of moving objects is implicit and it can＇t be queried. In this paper, we pro- pose a novel indexing method, called Basic HTPR＊ -tree （ History Time-Parameterized R-tree）, which not only supports predictive queries but also partial history ones. Based on the TPR ~ -tree, our Basic HTPR ＊ -tree adds creation or update time of moving objects to leaf node entries. In order to improve the update performance, we present a bottom-up update strategy for the HTPR ＊ -tree by sup- plementing compact main memory summary structure and hash index. Experimental results show that the update performance of the HTPR ＊ -tree （ Bottom-Up update ） is better than that of the Basic HTPR ＊ -tree （ Top-Down update ） and TPR ＊ -tree, and the predic- tive query performance is a bit less than that of TPR ＊ -tree.
出处
《小型微型计算机系统》
CSCD
北大核心
2012年第9期1873-1878,共6页
Journal of Chinese Computer Systems
基金
国家自然科学基金项目(90718027)资助
湖北自然科学基金计划重点项目(2008CDA007)资助
