Inference of hydrological events using the fuzzy subsets theory.

The mathematical foundations of the fuzzy subset theory in terms of the membership function are discussed and explored. In the paper is shown that the fuzzy inference can be a very important tool in engineering applications. A method for forecasting concentration time of a hydrograph in basins based on a fuzzy inference is presented In the same way a fuzzy runoff prediction system is developed using few data. There is an important relationship between the quantity of the information used in the adjustment and the quality of the answer of the model. This point is very relevant in a fuzzy model because as new data is added to the model the inference is increasingly better The application discussed here shows that reliable fuzzy inference models can be constructed using few data as it is very common in hydrology.