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- Follow steps 1 - 7 of Tutorial: Creating a <receptor>.txt file
- Create a buffer (e.g. 5m) around each receptor (MMQGIS -> Create -> Create Buffers)
- Subtract the original receptor polygons from the new buffer layer to obtain rings around the receptor (Vector -> Geoprocessing Tools -> Difference). The resulting layer contains (potentially overlapping) buffer rings, each associated with their unique receptorID and areaID of the receptor it originates from. (Step 2 and 3 can be repeated to obtain additional buffer rings, e.g. on one with 5m - 10m distance from the receptor)
- Use this layer to proceed with steps 7 - 9 of Tutorial: Creating a <receptor>.txt file
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