Data Dictionary Design for Travel Time Acquiring System Based on 3GS

The reasonable data dictionary can optimize data-accessing mode and improve data-accessing efficiency, so it is favorable to improve the performance of the system developing and operating. Aimed at the low efficiency of the travel time acquiring system based on 3GS (GPS/G1S/GPRS), this paper not only designed a traditional explaining type data dictionary, but also proposed two kinds of new data dictionaries, the querying type and the controlling type, by analyzing the data requirements of each technical links of the system. These three types of data dictionaries managed the data by classification and stratification from the viewpoint of application programs. These data dictionaries formed a simple, reasonable, and intuitionist logic mode of the system data and a new hierarchy data-accessing mode with dynamic attributes. It makes the data accessing and the program developing flexible, rapid, and convenient. Thus, the designed data dictionary is helpful to provide technical support for improving the system performance.