Miha Kralj (2011) Efficient visualisation of dynamic data using Web applications. EngD thesis.
The following chapters explain the reader the key parts of building an information infrastructure for effective representation of highly dynamic data on the internet. Such environment is characteristic for SCADA applications where there can be a few hundred updates per second. This updates are typically visualized as value changes on wiring diagrams. If we naively updated such a diagram as a bitmap image, let say once per second and we had a few diagrams updating at approximately the same time, there would be a lot of network traffic and a lot of processing on the server side. Besides, a bitmap that refreshes once per second in a browser doesn't contribute to the user experience. As an upgrade to such naive technique this paper shall give an overview of other means to achive the same goal, but with a fragment of time and server load. The techniques presented here are XHR (AJAX) for background data transfer, HTTP data streaming for multiple data package transfer from the server to the client whithin a single HTTP transaction, cache managers for caching data until they are updated and finally, SVG as an effective presentational layer. This thesis shall show that the above-mentioned techniques allow for real-time presentation of data from SCADA servers and other sources wih a minimal time lag. Furthermore, all the engaged techniques are natively supported by all major browsers without using plugins
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