DMQ4: Visualization Tools

The instrument data visualization tools are being developed as part of the DART DMQ4 workpackage. The objective of DMQ4 is to provide online, remote access to pilot working instruments and sensors. This objective involves:

To implement the visualization tools, serveral advanced techniques and softwares are involved:

Technologies

The new DMQ4 tools are supported on Internet Explorer version 6 and above and Firefox 1.5.x with ActiveX.

  • Languages: Java, Javascript, SPARQL
  • Java libraries: Sesame, Elmo, Java Server Faces (JSF)
  • Javscript libraries: Dojo, MochiKit, Plotkit
  • Servers: SRB, Fedora, Tomcat
  • Web technologies: Dynamic HTML, SVG/HTML Canvas (in supporting browsers), XHTML, ActiveX
  • Media Player: Windows Media Player

Architecture

  1. The user initiates a search query for a given experiment, project and date range.
  2. The DMQ4 web application generates SPARQL queries and performs the query against the RDF taken from the Fedora server.
  3. The DMQ4 web application processes the results RDF and uses the Elmo library to create Java objects.
  4. The resultant Java objects are processed using JSF to generate the required Javascript and HTML to be rendered by the client's web browser.
  5. The client processes the results of their query. The results contain URLs to the Fedora resources. These requests are processed by Fedora which accesses the underlying SRB server to deliver the sensor data and image files.

Previous Prototype

The previous prototype was based the following technologies:

Demo

Screen captures


DMQ4 welcome screen


Laboratory selection


Input validation


Instrument selection


Time selection


Query result


No data

Software

The DMQ4 Online instruments/sensors visualization tool is made up of the following components:
  • An interactive rendering of query results
  • Servlet based user interface to submit queries and display the results
  • A query layer to allow users to submit location and time ranges to return sensor results
To install the software:
  • Download and install Tomcat 6.0.4.
  • Download the DMQ4 Online Instruments/Sensors Visualization Tools.
  • Unpack the zip file and copy the following files into the lib directory of Tomcat:
    • el-ri.jar
    • jsf-1.2-api.jar
    • jsf-1.2-impl.jar
    • jstl-1.2.jar
  • Edit the tomcat-user.xml and add:
    <role rolename="manager"/>
    <user username="admin" password="" roles="manager"/>
  • Run the webapp-deploy target from ant to deploy the WAR file. It is expecting the default configuration options (localhost:8080/manager) for deployment. See the build-tomcat.xml to change any of these values.