User manual - gsi-upm/demo-smartopendata GitHub Wiki

This section explains the functionalities provided by the SmartOpenData tool for exploring and visualizing linked data resources. This section describes how users can use the main features of SEFARAD, including all those relative to add widgets, manage the data with different filtering methods, display the final results in some graphical widgets and use the SPARQL editor.

1 Add widgets

SEFARAD provides a semantic front-end to Linked Open Data which allows users to visualize, explore and analyse graphically the different features, attributes and relationships of the queried data. Different kind of widgets such as : numeric filter, tag cloud, gauge and maps can be used from SEFARAD. To add a widget please follow the steps described below.

  • Use the login form located on top-right corner of the browser to be logged into the dashboard system. Use “admin” and “1234” as user and password respectively.

  • Next, push the button “Add widget”. A window is shown for selecting the widgets. Now, you should be on the webpage shown the next figure.

  • Choose a map and a tag widget template. Chosen widgets should appears on the dashboard.

2 Faceted search

SEFARAD provides an interesting and useful feature for applying multiple filtering options on geo-spatial data. Faceted browsing capabilities can be applied by adding an accordion tag cloud widget and map widget. For enabling the filter option please follow the steps described below.

  • Add a tag cloud and map widget by following the steps described in section 1

  • Next, select a facet to be applied. Once a facet is selected, it is activated immediately and changes are shown on the map. Next figure shows an example about how users can explore geo-spatial data by using faceted browsing features.

  • Next, if it were necessary, users can apply filtering options on properties previously filtered.

3 SPARQL editor

SEFARAD provides a human-readable SPARQL editor for processing geo linked data queries. It is basically an editor in which users can customize SPARQL queries according to the geo-spatial parameters defined in the data resources. This feature provides a simple syntax highlighted text area bundled with features such as auto completion and the option to choose geo-spatial parameters for customizing queries. Current version involves a set of predefined human-readable queries. However, we are planning to include in the next release a feature in which human-readable queries can be defined and tailored by users. In order to process SPARQL queries by using the SPARQL editor please follow the steps described below.

  • Use the SPARQL editor located on top-center and click on it. Select a type of query from the combo box.

  • Next, select the parameters to be included on the selected query. A table result is generated for showing the properties returned. Next figure shows an example about an executed query by using the SPARQL editor.