منابع مشابه
Spatio-temporal join selectivity
Given two sets S1, S2 of moving objects, a future timestamp tq, and a distance threshold d, a spatio-temporal join retrieves all pairs of objects that are within distance d at tq. The selectivity of a join equals the number of retrieved pairs divided by the cardinality of the Cartesian product S1 S2. This paper develops a model for spatio-temporal join selectivity estimation based on rigorous p...
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This paper proposes a cost model for selectivity estimation of predictive spatio-temporal window queries. Initially, we focus on uniform data proposing formulae that capture both points and rectangles, and any type of object/query mobility combination (i.e., dynamic objects, dynamic queries or both). Then, we apply the model to non-uniform datasets by introducing spatio-temporal histograms, whi...
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We address the problem of performing efficient similarity join for large sets of moving objects trajectories. Unlike previous approaches which use a dedicated index in a transformed space, our premise is that in many applications of location-based services, the trajectories are already indexed in their native space, in order to facilitate the processing of common spatio-temporal queries, e.g., ...
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Many applications capture, or make use of, spatial data that changes over time. This requirement for effective and efficient spatio-temporal data management has given rise to a range of research activities relating to spatio-temporal data management. Such work has sought to understand, for example, the requirements of different categories of application, and the modelling facilities that are mo...
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Many novel spatio-temporal applications deal with moving objects. In such environments, a database typically maintains the initial position and the moving function for each object. Instead of updating the database whenever an object position changes (which is not manageable), updates are issued whenever a function parameter (velocity, direction, etc.) changes. For simplicity, we assume that obj...
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ژورنال
عنوان ژورنال: Information Systems
سال: 2006
ISSN: 0306-4379
DOI: 10.1016/j.is.2005.02.002