Cityzones: A Geospatial Multi-Tier Software Tool to Compute Urban Risk Zones

Abstract

CityZones is an online platform to support in the definition of a polygonal Area of Interest (AoI) over any urban area to be categorized according to three different levels of risks (low, medium, and high), taking as reference the existence of mitigation facilities within that area. As urban emergencies in general will typically demand the assistance of hospitals (to attend victims), firefighters (for rescue operations and damages reduction), policemen (to control and manage critical situations), and even metro stations (for evacuation), the risk zones within an AoI will be computed according to the distances to such facilities, which are extracted from the OpenStreetMap collaborative database. The coordinates of an AoI are defined at the client-side and submitted to a server as a regular or irregular polygon, which is then stored in a GeoJSON file along with the classification configuration for further processing according to a multi-tier pipeline. Adopting a configurable square-based mathematical model to compute distances and relative risk levels, the risk zones are computed on-demand and exported to CSV files to be used by any application, with an additional visual representation for visualization on the defined web client. Moreover, as a practical exploitation of the computed maps, the CityZones tool also suggests ideal positions for sensors-based Emergencies Detection Units (EDUs) within an AoI according to the chosen positioning algorithm, assuming that the computed risk zones indicate how severe an undetected emergency would be. The developed tool is highly adjustable, being easily reconfigurable to incorporate other elements when computing risk zones, potentially supporting emergency-aware smart cities projects.

Keywords: Geospatial data, Emergencies, Smart Cities, OpenStreetMap.