به كارگيري منطق فازي در ارزيابي شبكه هاي آبياري

Conducting Fuzzy system in Irrigation Performance Assessment

Improving an integrated model on performance assessment of Irrigation systems is subjected to uncertainty of natural parameters, and vagueness or fuzziness characteristics of operation and maintenance parameters. Application of these linguistic-expression parameters usually is impossible, and a fuzzy approach is recommended. The main issue of this method is to provide indicators, based on subjective judgments, and applied linguistic-expression beside the Technical, Economical, and Environmental indicators. In this method assessment is based on the judgments of Water users and Managers separately. The assessment of Irrigation system also is possible by defined seven expression indicators of Water usersʹ judgment. Initial indicators define initial condition of the system, and fuzzy niles are defined for interaction-influence of indicators. The Mamdani and Sugeno fuzzy inference is conducted. The selection of the defuzzification methods; center of area (COA) or Mean of Maximum (MOM) is not important in this model (r2 >- 0.98); the difference between two methods is less than 7%. Results comparison to Standard Method indicates that, COA gives the better result. The model tested in Moghan Irrigation system, and is compared with Ghazvin irrigation system. 27% lower management performance assessment result on Ghazvin Irrigation system is not because of shortage of Irrigation water only, but it is subjected to similarity (<16%) or diversity (>44%) of water users and service agencyʹs judgments in Moghan and Ghazvin respectively. It is happened because of differences of social-management conditions of two systems.