select code,name, org_lon,org_lat,sum(bytes) as bytes,sum(visitors) as visitors from public.sdb_ac where code in (select DISTINCT code from public.sdb_ac) group by code,name, org_lon,org_lat ;
Prototype theory -- is a mode of graded categorization in cognitive science, where some members of a cateogory are more central than others. For example, when asked to give an example of the concept furniture , chair is more frequently cited than, say, stool . P ...
M.F. Goodchild The growth of any science depends on several condtions being met There must be good-quality data available There must be well-formulated hypotheses that can be formalised mathmatically. so that they can be suject to empirical testing There must be rigor ...
The areas between migration, or other movement, occurs are connected by a band whose width represents the quantity moved. 1)Ideally a desirable parsing strategy is one which yields only a linear growth in the number of movements needing to shown. Wherei the geographical space is considered t ...
The RDF data model is similar to classic conceptual modeling approaches such as Entity-Relationship or Class diagrams, as it is based upon the idea of making statements about resources (in particular Web resources) in the form of Subject-predicate-object expressions. These expression are known as T ...
Sophistical procedure are often required for collaborative geospatial problem-solving and decision making while most researchers in GIS-relevant studies pay much attention to the generation of geographic datasets, information on how these data are derived is often ignored. spatial privenance def ...
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