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Table 1 Description of various data and their sources used as input into the development travel time to the public health facilities in northern Namibia.

From: Spatial modelling of healthcare utilisation for treatment of fever in Namibia

Map Layer Description Classification Speed (km/h) Model
Land use/land cover Spatial representation of all different land use and land cover types. Two land cover grids were processed (1) basic land cover grid (2) combined grid that incorporates roads and rivers with same resolution as the DEM Tree cover, broad leaved deciduous or evergreen 5 WALKING
   Tree cover, needle leaved, deciduous or evergreen 5 WALKING
   Tree cover, other 2 WALKING
   Shrub cover 5 WALKING
   Herbaceous cover 3 WALKING
   Sparse herbaceous 4 WALKING
   Cultivated and managed areas 5 WALKING
   Bare areas/desert 2 WALKING
   Water Bodies 0 NONE
Roads Classified into three broad categories; Primary roads (class A), Secondary roads (class B); Tertiary roads (class C). Each road class was assigned a slightly different speed. Primary roads 80 NONE
   Secondary roads 60 NONE
   Tertiary roads 10 CYCLING
Rivers GIS layer representing barrier to movement. Only major rivers were used to reduce the complexity of running the algorithms NA1 0 NA1
Digital elevation model Altitude values that are used in anisotropic calculation; Original DEM 30 m ASTER grid; resampled to 100 m pixel size Degree of Slope (< 0.5°) 4.88 WALKING
   Degree of Slope (5.0°) 3.71 WALKING
   Degree of Slope (10.0°) 2.71 WALKING
   Degree of Slope (20.0°) 1.41 WALKING
   Degree of Slope (30.0°) 0.66 WALKING
  1. The assumed travel speeds for each input feature are also shown
  2. 1. NA is an abbreviation for ' Not Applicable'