NU^2RA:一种路网中不确定移动对象范围查询分析方法  

NU^2RA:An Analysis Method for Range Queries over Uncertain Moving Objects in Road Networks

作　　者：陈逸菲[1,2] 秦小麟[1] 

机构地区：[1]南京航空航天大学信息科学与技术学院,南京210016 [2]南京信息工程大学信息与控制学院,南京210044

出　　处：《计算机研究与发展》2010年第6期1060-1069,共10页Journal of Computer Research and Development

基　　金：国家"八六三"高技术研究发展计划基金项目(2007AA01Z404);江苏省支撑计划基金项目(BE2008135)

摘　　要：目前移动对象的各类查询研究大多假设对象的位置确切可知,但实际上除了更新时刻外,其他时间对象的位置只是一个可能的范围.因而大多数基于确切位置的查询算法并不可行.而现有的涉及不确定性的查询方法大多仅针对自由移动的不确定查询或者不确定目标.针对道路网中查询和目标位置均不确定的情况,提出了一种NU2RA分析方法.根据查询范围对网络进行划分,用分布码表示目标的可能分布,得到不确定目标与不确定查询范围的22类拓扑关系,并且给出了目标在不确定查询范围内的概率计算方法.该方法不依赖于具体的不确定移动对象模型,对不确定历史轨迹和不确定的近期将来运动趋势同样适用.The positions of moving objects are assumed to be exactly known in most researches on different types of queries. In fact,except for updating instants,moving objects＇ exact locations are not known,but are bounded by uncertainty regions. So the algorithms based on precise positions are inapplicable. Existing algorithms that involve uncertainty concern either uncertain querying objects or uncertain interesting objects moving in Euclidean space. Aiming at the uncertain range queries over uncertain objects constrained in road network,an analysis method named NU2RA is proposed here. The length of shortest path instead of the Euclidean distance is used. Network distances between two uncertain objects are defined. The network is partitioned into 5 parts according to uncertain query ranges. Possible distributions of objects are represented with distribution codes,and 22 kinds of topological relations between uncertain objects and uncertain ranges are identified. Query answers are augmented with probabilistic guarantees of the validity of answers. Probability evaluation in each case is derived. NU2RA,being independent of concrete uncertain moving objects models,provides the general topology analysis and probability evaluation for uncertain range queries in road network. The method is applicable to both uncertain history trajectories and uncertain current and near future motions of moving objects.

关 键 词：不确定性 移动对象 范围查询 概率 路网 

分 类 号：TP311.13[自动化与计算机技术—计算机软件与理论]