Numerical methods and fuzzy parameters: an environmental impact assessment in aquatic systems


This paper proposes to analyze the dispersion of pollutants in aquatic systems, solving the advection–diffusion equation using numerical methods and fuzzy sets. For solution, numerical approximations were adopted, based on the finite element method for the spatial discretization and Crank–Nicolson for the time variable. The parameters of the equation were modeled taking into account aspects of multiple varieties of natural phenomena, based on fuzzy sets. The two-dimensional model resulted in the value of pollutant dispersion taking into account the flow velocity, in situations of prevailing winds in the region of a reservoir of Sao Paulo. According to the results, it was observed that the integration of the numerical methods and the fuzzy parameters is a potential instrument for environmental process analysis. The rule-based systems allowed a better design of the local natural phenomena. The spread of the plumes of pollutants was well defined by the model and the simulated scenarios are in agreement, from a qualitative point of view, with the local reality.

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Correspondence to Elaine Cristina Catapani Poletti.

Additional information

Communicated by Geraldo Diniz.

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Poletti, E.C.C., Meyer, J.F.d.C.A. Numerical methods and fuzzy parameters: an environmental impact assessment in aquatic systems. Comp. Appl. Math. 36, 1517–1528 (2017).

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  • Environmental impact
  • Aquatic systems
  • Advection–diffusion equation
  • Numerical methods
  • Fuzzy parameters

Mathematics Subject Classification

  • 35N05