Web Data Acquisition And Display System Based On Data-segment Technology Of MDSplus

Based on the needs of data storage and interactivity of long pulse or steady-stateoperation for ITER and the future fusion reactor, this article has designed a Web dataacquisition and display system which is made up of data-acquisition subsystem anddata-display subsystem. Data-acquisition subsystem is responsible for obtaining the longpulse experimental data which is processed by MDSplus Segmented-Record technologyand stored into the MDSplus database as high sampling rate data. At the same time,data-acquisition subsystem resamples the long pulse experimental data to get low samplingdata which is also stored into the MDSplus database. Data-display subsystem achieves thedata stored in the MDSplus database and displays the data in the window of browser.The data-acquisition subsystem is developed in the real-time system of LabVIEW RTand takes multi-threading technology to realize the mechanism of multi-channel,multi-tasking and continuous data-acquiring. The hardware part of the data-acquisitionsubsystem is realized by PXIe-1062Q chassis, PXIe-8133controller and PXIe-6368data-acquisition card which is provided with high speed and has good property ofmechanical package and high sampling rate etc. The data-display subsystem is based on theASP.NET architecture, and it adopts Segmented-Record technology to readSegmented-Record data from MDSplus database, displaying the data on web page by usingNI Measurement Studio control library. Users can read certain data segments from the longpulse data according to their special needs. Also, the system develops an efficient strategyfor reading Segmented-Record data, showing the waveforms required by users accuratelyand quickly.The data acquisition and display web system presented in this article has already beendeployed and tested on J-TEXT Tokamak, and is proved to be reliable and efficient toachieve the initial design goal.