Design And Implementation Of Geographic Trajectory Similarity Analysis Service

Geographic data is data that directly or indirectly relates to a certain place on the earth.It is also the data of the natural phenomena and social phenomena that represent the geographical location and distribution characteristics.In the user business using geographic data,a novel and practical research direction is to analyze the similarity of geographic trajectories.In the analysis of criminal accomplices,the general criminal accomplices have the same or similar trajectories.Through the retrieval of similar tra-jectories and the ranking of similarities,the suspects who are most likely to cooperate with crimes can be quickly identified,thus greatly improving the efficiency of recon-naissance.However,the current industry-related systems are basically concerned with the storage,display and tracking of trajectories.There is no good and stable solution for trajectory similarity retrieval.In response to the above problems,this thesis designs and implements a geo-graphic trajectory similarity analysis service.The service includes two main data sub-services,trajectory data sub-service and map tile data sub-service.The specific im-plementation method is based on the vantage point tree structure extension to realize the full-text search library Lucene's VpTree index,which is used as trajectory data re-trieval.And the function of trajectory data insertion and initial indexing is developed around this core data structure.The map tile data sub-service is based on Mapbox universal map tile standard,and the geo-mathematics knowledge such as WGS-84 co-ordinate system and Web Mercator projection method realizes the functions of reading and partial updating of map tiles.The geographic trajectory similarity analysis ser-vice obtains the trajectory data and the map tile data from the above two sub-services respectively,and then realizes the visualization on the browser side through the inte-gration of the front-end library,thereby enabling the user to conveniently and quickly achieve the target of similar trajectory retrieval.The main work of this thesis is to introduce the design and implementation of the above two sub-services.First of all,this thesis introduces the main technical concepts and related standards currently involved in geographic trajectories similar services.Then the requirements analysis of the entire system was carried out,and the overall architecture design was carried out using the software architecture 4+1 view model.Then the detailed design and implementation of the two main functional modules of the trajectory data subservice and the map tile data subservice are introduced respectively.In the process,some performance and model problems appearing in the system are also discussed and analyzed,providing a better solution.After that,the test of the entire service is introduced,including the process details of unit test and functional test,and the results of the service performance test are shown by a line chart and a bar chart.Finally,this thesis analyzes in detail the improvement of the geographic service trajectory similarity analysis and the limitations of the current version,and analyzes and prospects the future development of the service.