Geoscience Reference
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Figure3.3(a))andanintervaloftimewiththeTF“inearlyJanuary2001”(see TF #9 ,
Figure 3.3(b)).
Figure 3.3. Example of an application of tiling: a) spatial features on a
communal administrative tiling and b) temporal features on a monthly
calendar tiling - illustration taken and then adapted from [PAL 10d, PAL 11]
Standardization by tiling will then be performed in two steps: the choice of the
segmentation for each dimension and then the representation of the information of
each first-level index in this tile-based grid. Thus, the spatial information needs a
regular or administrative tiling (commune, county, etc.) of the zone covered by the
document repository and a calculation of intersections of the SFs of the index and of
this tiling. Similarly, temporal standardization needs a regular or calendar tiling (day,
of intersections of the TFs of the index and of this tiling.
Figure 3.3(a) illustrates the communal administrative tiling of the zone. The SF
“near Bayonne” (SF #5 ) is in intersection with seven tiles (communes surrounding
The TF “in early January 2001” (TF #9 ) is included in the T 9 tile (month of January
The index excerpt presented in Table 3.1 illustrates the application of temporal
tiling described in Figure 3.3(b): we can find the corresponding frequencies for the
tiles T 1 , T 2 ,...,T n .For example, TF #6 is in intersection with four tiles (T 2 , T 3 , T 4 ,
T 5 ); the binary frequency relative to each of these tiles will be increased by 1. As for
the tile T 3 , it is in intersection with two TFs (TF #2 and TF #6 ); consequently, it will
takes into account the scale of the feature with respect to that of the tile. For example,
such a calculation will determine a proportional frequency of 1.08 for the application
of TF #2 and TF #6 on the tile T 3 .
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