| The fussy assessment (FA) method has been chosen as the main assessing way from a lot of methods in environmental quality assessment (EQA). Not only the FA method has the mature development and has been widely used in many fields and the ideal "membership" is in accordance with people thinking, but also through the combination calculation of power vector and membership matrix obtain result of synthesis appraisal frame conforms to people's thought custom. Therefore draws up under this frame carries on the discussion.This article has conducted the research in the following 4 aspects:1)Membership function questionThe problem of determinating the membership is the key of FAEQA. The membership idea has not been defined until the membership function is chosen certainly. In this paper, a work of deducing for the membership function has been done. For some pollution indexes, a hypothesis has been proposed in this paper, in which some pollution particles are imagined moving randomly within one's body all the time until they are killed or passed away. While the particles aggregate one another into groups, they will grow up and lead to disease. With this hypothesis , the NN-DLA model, which is involved in "Fractal grows" has been used. With the help of computer, a mathematical model of membership function has been established, and the model parameter is determined by W-F's Law. So that, a membership function which can be wildly used has been obtained.2)Time series questionIn the traditional EQA methods, the calculation is carried out with the average value of the time series of all pollution indexes, the chaotic can not be referred to. In this paper, the R/S analysis method proposed by Hurst has been used. The fractal dimension number means the seriousness of pollution indexes density undulation degree. It is more reasonable to refer to the fractal dimension numbers in the power value distribution.3)Indexes choice, power value assignment and choice of synthesis operation operatorThese 3 questions all may have the different choice, however the fuzzy theory serves without any restraint, therefore they all haven't the determinism. In the synthesis operation operator choice, through the value and the related function type comparison, points out the operator the deficiencyof M (∧,∨), and recommendation use the operator of M (·, +) .About the indexes choice, takethe water quality appraisal of surface water as example, proposed besides the "superior" indexes not to participate in the link to appraisal, other indexes all must participate in the link to appraisal. To the assignment problem of power value, in usually uses power value has the direct ratio with the relative concentration in the linear regular foundation, proposed the S function of "power value (?) relative concentration".4)Choice question of check and measure location To certain region, even if the identical time, the examination data of different position is not to certainty same. In order to insure the affirmatory and reasonable environment appraisal conclusion, there must have a science designation examination position. Through the transformation of heredity optimization, causes the heredity algorithm which originally can not use in the search to be possible to use in the distribution search of pollutant density field.Based on the above idea and method, the fussy assessment method which both maintain the traditional synthesis appraisal frame and have the new thought has been proposed, and the contrast proof has carried on through an example.
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