5. Spatial Data Analysis

In this topic, we introduce a series of spatial data processing and analysis methods according to the geospatial characteristics of IoT data. Through the use of the Civil IoT Taiwan Data Service Platform, we will develop the following units for a more in-depth introduction.

• 5.1. Geospatial Filtering

  We use Civil IoT Taiwan's earthquake and disaster prevention and relief data and filter the data of specific administrative areas by overlaying the administrative area boundary map obtained from the government open data platform. Then, we generate the image file of the data distribution location after the superimposed map. In addition, we also demonstrate how to Nest specific geometric topological regions and output nested results to files for drawing operations.

• 5.2. Geospatial Analysis

  We use Civil IoT Taiwan's sensor data to introduce more advanced geospatial analysis. Using the GPS location coordinates in the site information, we first use the package to find the largest convex polygon (Convex Hull) to frame the geographical area covered by the sensor. Then we apply the Voronoi Diagram package to draw the distribution status of each sensor on the map according to the sensor and crops out the area of influence of each sensor. We adopt the spatial interpolation method for the space between sensors, applying different spatial interpolation algorithms. We then populate the spatial map with values based on the sensor values and generate a corresponding image output.