Visualizing Linked Data Event Streams with QGIS

How to monitor and analyse Linked Data Event Streams and make informed decisions with QGIS

Photo by ian dooley on Unsplash

Linked Data Event Stream (LDES) is a powerful way to represent and share real-time data, but visualizing and monitoring this data can be challenging. QGIS, a free and open-source geographic information system (GIS) software, can create effective maps of LDES data, making it easy to monitor the content in real-time and use it as a decision support system.

One way to use QGIS is to visualize sensor data in the context of smart city applications. For example, you can use QGIS to display sensor data such as air quality, noise levels, or traffic flow on a map. By layering this data on top of a base map, you can gain insights into how different factors are related and make more informed decisions about disasters and other rapidly changing events.

Linked Data Event Stream

A Linked Data Event Stream is a constant flow of immutable objects (such as version objects, sensor observations or archived representation) containing information about an event or state change originating from a system that continuously creates data.

For more information about Linked Data Event Stream (LDES), you can read this article:

Linked Data Event Streams explained in 8 minutes

Visualizing geospatial data

QGIS can be used with PostgreSQL/PostGIS to visualize geo data in real-time. In this way, the powerful, open-source relational database management system PostgreSQL stores and manages large amounts of spatial data, and QGIS visualizes all the data. PostGIS is an extension of PostgreSQL that provides spatial data types and functions for working with spatial data.

For more information about how to ingest Linked Data Event Streams into PostgreSQL/PostGIS, read this article (data flow is the same for TimescaleDB and PostgreSQL):

Linked Data Event Streams and TimescaleDB for Real-time Timeseries Data Management

Connecting QGIS to a PostgreSQL/PostGIS database lets you access and visualize your geo data in real-time.

Image by author

For example, you can set up a live feed of sensor data to a PostgreSQL /PostGIS database and then use QGIS to display that data on a map in real time. Using the Time Manager plugin makes adding a time bar to the map possible. This allows you to see spatiotemporal data in a user-friendly manner. Because an LDES makes it possible to stay in sync with the source database, it is possible to make quick decisions based on the current state of the data.

Image by author

Conclusion

In conclusion, QGIS is a tool that can be used to visualize and monitor Linked Data Event Streams (LDES) data with a spatiotemporal component. It offers a wide range of spatial analysis and visualization tools that can be used to create maps and visualizations of real-time data from LDES streams. Additionally, QGIS can be connected to a PostgreSQL/PostGIS database to visualize the data in real time.

Now you should be in good shape to use QGIS in combination with Linked Data Event Streams and their advantages. You can find more information on the websites underneath.

Publishing data with Linked Data Event Streams: why and how

Linked Data Event Streams

If you like what you read, be sure to ❤️ it — as a writer, it means the world. Stay in touch by following me as an author.

Contributors to this article are ddvlanck (Dwight Van Lancker) (github.com), sandervd (Sander Van Dooren) (github.com) at Smart Data Space (Digital Flanders, Belgium). In a rapidly changing society, governments need to be more agile and resilient than ever. Digital Flanders realizes and supervises digital transformation projects for Flemish and local governments.