Fuzzy Logic Algorithm of Ecological Forest Zoning in the Vicinity of Chemical Plants Based on a Hierarchical System of Fuzzy Composite Indices

A hierarchical system of fuzzy composite indices calculated for natural forest levels is put forward. For each of the levels, its own composite index (CI) is calculated, which is further used to calculate the higher level generalized composite index (GCI). Lower level fuzzy composite indices can be calculated using weighted means with expert-assessed weighting factors. The fuzzy GCI is proposed to be calculated by the fuzzy principal component analysis (PCA) generalized to fuzzy indices. In the proposed algorithm, symmetric triangular fuzzy numbers are used and PCA is applied only to the centers of triangular fuzzy numbers; the fuzzinesses in calculating the principal components are taken into account only in linear combinations of the fuzzinesses of the initial indices. An example of using the proposed fuzzy logic algorithm and the fuzzy principal component analysis for ecological forest zoning in the vicinity of chemical plants is given.