Modelling and Analysing Circular Moving Regions

Many real-world phenomena are characterised not only by move- ment but also by a spatial footprint that evolves over time. While moving object database systems provide rich support for trajectory data, modelling deformable moving regions remains challenging. To address this limitation, we introduce the temporal circular buffer (tcbuffer), a novel data type for representing circular moving re- gions whose position and radius vary continuously through time. The data type, together with a collection of spatial, temporal, and spatiotemporal operations, has been fully integrated into Mobil- ityDB, an open-source platform for managing and analysing tra- jectory data. In this demonstration, we showcase the capabilities of the proposed data type through a real-world maritime applica- tion involving underwater noise generated by vessel traffic. Using Automatic Identification System (AIS) data, we reconstruct vessel trajectories and enrich them with acoustic information to model vessel noise footprints as temporal circular buffers. Through six interactive queries, we demonstrate the visualisation of noise foot- prints, the monitoring of acoustic exposure within marine protected areas, and the forecasting and mitigation of future noise impacts. These examples highlight how the tcbuffer data type enables the representation and analysis of circular moving regions by modelling the evolving area of influence associated with moving objects.