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Design and implementation of data storage layer in Urban Rail Transit Data Platform

At present, Communication Based Train Control System (CBTC) is widely used in the urban rail transit. CBTC generates a large number of electricity, locomotive and other data, such as train number, locomotive state and fuel consumption parameters and so on. In this paper, we call these data Urban Rail Transit Data (URTD). This paper mainly designs and implements the data storage layer of Urban Rail Transit Data Platform (URTDP), which consists of data processing and storage module. Firstly, according to the characteristics of URTD, we design a set of portable data processing methods. And we use MapReduce, the distributed computing framework, to implement the processing. Secondly, through the analysis of the requirements for data queries, we design and implement the HBase table schema for URTD. Meanwhile, this paper puts forward some optimization schemes for the common problems existing in the implementation process. Finally, test results show that the data storage layer has good query performance in the experiment environment.