Uncertain space-time trajectory data range query method under road network environment

Abstract

The invention discloses an uncertain space-time trajectory data range query method under road network environment. The process includes that firstly, a road network is divided into divided areas with the number of K; a hash table is established according to sides and divided corresponding relations; boundary points of the divided areas are calculated, and a two-dimensional space R tree index is established; the shortest path distance among the boundary points of each dividing is calculated; a one-dimensional R tree time quantum index is established for each dividing, and a B+ tree for storing trajectory data for each one-dimensional R tree is established; then, the earliest arrival time and the latest leaving time of a certain trajectory and an uncertain trajectory are calculated, and a unit segment assemble and divided beginning and ending time are inserted into time interval components; and finally, according to the dividing of a query point, distance information of a divided boundary point and the query point is calculated, and therefore a query result is obtained. According to the uncertain space-time trajectory data range query method under the road network environment, a small amount of input / output (I / O) operations and online calculation are only needed to be performed for a part of dividing, the query results can be obtained, and the query results are high in accuracy degree and fast in response speed.

Description

technical field [0001] The invention relates to the field of information retrieval, in particular to a range query method for uncertain time-space trajectory data in a road network environment. Background technique [0002] With the development of the economy, more and more people own cars, and traffic accidents have become the largest cause of accidental casualties in the world. In the investigation of traffic accidents, if the vehicles passing through the designated area of ​​the accident can be analyzed during the time of the accident, the perpetrator or potential witnesses can be quickly found, the processing time of traffic accidents can be accelerated, and the efficiency of hit-and-run cases can be improved. Under such demands, it is very necessary to invent a method for efficiently processing range query of uncertain trajectory data in road network environment. With the rapid development of communication technology and global positioning technology, the demand for lo...

AI Technical Summary

Problems solved by technology

[0006] The invention provides a range query method for uncertain spatio-temporal trajectory data in a road network environment, which solves the problems of large amount of calculation, low query efficiency, many index files, many times of disk I / O reading and large system consumption in the existing method Insufficient problems, and can be applied in traffic accident query, urban traffic condition analysis, fuzzy trajectory data mining, etc., and the query results are efficient and accurate

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