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S. Santra and S. Biswas
Fig. 8 Geomorphology map of the area
toward the problem. The main problem with the fuzzy sets is the number of rules
(predefined relations between input set and output) increase exponentially with the
number of inputs used. To overcome this shortcoming, hierarchical fuzzy logic (HFL)
is introduced where inputs are sorted according to relative importance, and then
fuzzy logic-based calculations are carried out stepwise. Here, we have used the same
approach, and to find the initial relative weights among the parameters, AHP is used.