of Fuzzy logic in the Design of Drainage Systems and Vegetated Waterways under
(1995-1996/ Research Team: J. Perret, S. Prasher)
In this project, we evaluated two methods for analyzing uncertainty in agricultural systems design. Specifically, the First and Second Order Analysis and the Fuzzy Logic approach are compared in terms of their advantages and reliability in dealing with uncertainty in the design of drainage systems and vegetated waterways. The two methods were used to evaluate the uncertain parameters in the Hooghoudt and Van Schilfgaarde equations which represent steady state and transient drainage conditions, respectively.
Results indicate that both approaches can provide the designer with an indication of reliability of the estimates, a way of selecting a design option which meets a specified probability of success, as well as a means of comparing the relative importance of uncertainty in various input parameters. Also, the two techniques have the common advantage of being simple and requiring fewer data sets compared to other more comprehensive stochastic methods. Although both methods appear to be reliable, the Fuzzy Logic approach provides a more conservative design since it tends to generate slightly higher variances compared to that obtained by the First and Second Order Analysis.(Click here for more info)
© 2000 Johan Perret