No hay notas en la diapositiva.
United Kingdom244,820 km² (79th)94,526 sq mi Guinea 245,857 km² (78th)94,926 sq mi
Top three show the level 1, Level 2 and then Level 3 and 4 intersections.If we stored all of these intersections we would have 85 matches. What we do find is that some of the cells are complete matches these don’t need to be broken down to the lower level cells. Like in Figure 4.However we still have a large number of matches, depending on the cells per object setting on the index the tessellation process will stop once it hits the limit as we have in Figure 5.This shows how imprecise the index is. It is only meant as a filter to avoid doing a very expensive calculation on all the data.
GIS data is used to produce both digital and paper maps - the underlying data is identical. GIS data is supplied in vector format - as opposed to raster format. Vector data uses geometric objects (points, lines or polygons) to depict spatial information. For example, linear features like roads and railways are depicted as lines. The raster data model represents geographical space by dividing it in a series of cells. The further you zoom in the more obvious the "cells" (also known as pixels) become. Raster data is available as printed paper maps, or on digital media (CD Rom or DVD Rom).
Latitude: Imaginary horizontal mapping lines on the Earth. They are known as "parallels" of latitude because they run parallel to the Equator. The number of degrees of latitude shows how far north or south of the Equator a specific location is.
Longitude: Imaginary vertical mapping lines on Earth known as "meridians" of longitude. The number of degrees of longitude shows how far east or west of the Prime Meridian a specific location is.
Geocentric model of the universe is the theory that the Earth is the center of the universe and other objects go around it.