| With the rapid growth of trajectory big data,efficient mining,analysis,and visualization of trajectory big data have become urgent issues.Efficient mining,analysis,and visualization techniques can transform trajectory big data into a form that is easy to understand and operate,allowing people to observe the spatial and temporal distribution,clustering patterns,and other features of trajectory big data in an intuitive way.To dig deeper into the hidden value of trajectory big data,a series of big data mining techniques and methods need to be adopted,and the Hadoop distributed computing technology system is currently the key technology for solving the storage and management of big data.In practical applications,the 5V features of trajectory big data will increase system overhead,slow down system performance,and increase deployment and maintenance costs.Therefore,it is necessary to study a visualization model and storage management technology that is suitable for trajectory big data,in order to better explore the hidden value in trajectory big data and provide data reference and decision support for urban traffic management and planning.Based on the above background,this paper first systematically analyzes the existing trajectory big data visualization methods and proposes a vector field-based visualization model based on the visualization ideas of vector fields,which is applied to the trajectory big data of Beijing taxis.Secondly,in order to better calculate and analyze trajectory big data,the advantages of Hadoop and MySQL technology in processing data of different scales are utilized to design a platform database storage management architecture.Finally,a trajectory big data analysis platform is implemented and developed,which can visually display data features and rules and provide users with better data mining and analysis services.The main research content of this paper is as follows:(1)In response to the problem of trajectory big data visualization model,a vector field visualization model oriented to trajectory big data is proposed.This method processes and projects the direction and speed of vehicle movement in the form of vectors,draws streamlines to complete the vector field visualization model,and intuitively reflects the congestion trend,aggregation state,and other information of vehicles.At the same time,the Web GL technology is used to design the vector field visualization rendering effect,generate a large number of particles in the view window,and simulate the actual effect of vectors through the movement of particles,completing the visualization rendering of the vector field.Compared with traditional methods such as heat maps and scatter plots,this method pays more attention to the "prediction" of future data and can effectively identify congestion trend points and calculate congestion indices quickly.(2)In response to the problem of trajectory big data storage management,this paper combines Hadoop and MySQL databases to achieve the requirements of massive data processing and querying,using HDFS to store large-scale data,MySQL to store small-scale data,and using Spark to implement data processing and analysis.The data engine mainly uses SQL parsing,the relational database is the Inno DB query engine provided by MySQL internally,the distributed database is the Spark SQL query engine,the cache is Redis,and the file retrieval is the Elasticsearch engine.Combined with the overall architecture of the trajectory big data visualization platform,detailed entity objects,relationship types,and table designs are designed.(3)According to the research content,a trajectory big data visualization platform is designed and developed.The platform can process massive trajectory data and generate corresponding visual analysis results based on user needs,including trajectory point heat distribution maps,operating status scatter plots,operating density grid maps,three-dimensional operating status trajectory maps,and congestion trend vector field maps.The analysis results provide users with intuitive,fast,and accurate displays of vehicle movement status.At the same time,the platform also provides user management services,such as permission configuration,menu allocation,and has good scalability. |
