【摘 要】
：
针对目标对象与查询发出者皆为不确定移动对象的情况,提出了一种时间区间上的距离范围查询（DRqTI）.此类查询搜索出数据集中在给定时间区间内,到查询发出者距离不超过阈值的目标
【基金项目】
：
国家自然科学基金（41301407）
论文部分内容阅读
针对目标对象与查询发出者皆为不确定移动对象的情况,提出了一种时间区间上的距离范围查询（DRqTI）.此类查询搜索出数据集中在给定时间区间内,到查询发出者距离不超过阈值的目标对象,查询结果中包含对象满足查询条件的有效时间段和匹配度.提出了基于轨迹、基于时间区间和基于距离的三种剪枝策略,并给出了精炼和匹配度计算方法,在此基础上设计了查询处理算法.实验分析表明,三种剪枝策略中基于距离的方法性能最佳,提出的算法能有效处理DRqTI问题.
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