measuring several centimeters or the property boundaries measured up to a millimeter)
to global ones (as analysis of temperature on the surface of the sea and global
warming).
- Time. The analysis extends to the past (as historical study of population
migration, study of the structure of archeological sites or detailed mapping of
continents’ movements) and to the future (e.g., attempts to foresee the hurricane
movements, ice melting, urban growth).
Geo-informational systems differ from other informational systems namely by
having effective opportunities for analyzing spatial data and performing spatial
modelling of objects and phenomena [6,7]. GIS – is not just a computer system for
making maps, though it can make maps at different levels, in different projections. GIS
is an analytical tool. The main advantage of GIS is the ability to determine the spatial
relations between the map’s objects. GIS does not store a map in any generally accepted
meaning of this word and does not store a specific image or representation of
geographical areas. Instead GIS stores data which allow to draw the required kind in
accordance with the specific purpose.
GIS-analysis is geospatial analysis, performed with the means of geo-
informational systems and technologies [8]. GIS-analysis is one of main functions of
GIS, which performs powerful geoprocessing, so that to work out additional and
analytical information, using different analytical means of GIS. Analytical
opportunities of GIS allow obtaining answers to multiple spatial inquiries, to solve
numerous spatial tasks in various subject areas. Using GIS-analysis one can combine
information from independent sources and obtain new sets of information (results).
Spatial analysis based on GIS, opens new ways to understanding spatial heterogeneity
and spatial dependencies, that can make spatial analysis a powerful source of
information. All GIS are built on the basis of formal models that depict the placement
of objects and processes in space. Geographic models of our world constitute
informational basis of GIS-analysis. Models are useful and are used in a wide spectrum
of using GIS from simple assessments to foreknowledge of a future landscape. In the
past modelling was often required for both GIS and special program software, designed
for functioning in the sphere of dynamic modelling. But with the growth of hardware
and software power of GIS now one can go back to researching this correlation.
Modelling in GIS sets a number of important questions, including those on scaling,
accuracy, projecting infrastructure objects, aiming to facilitate models’ exchange. In
geo-informational systems geographic objects are represented by two main types of
models: vector and raster. In vector model geographical objects are represented by
graphic primitives – point, linear and polygonal spatial objects. In raster model
geographical objects are represented by matrix of cells. Each layer is one attribute. The
size of the cell determines the accuracy of mapping geographical objects and analysis’
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