Research On Optimization Of Water Quality Assessment Method Based On Cloud Model

Water quality assessment is the foundation of water environment management.Through water quality assessment,the water environment quality can be accurately mastered,which provides theoretical basis for water environment planning and water pollution prevention and control.However,water environment is a system full of uncertain factors and complicated changes.The traditional evaluation method does not take into account the complexity and non-linearity of water environment problems,and its application has certain limitations and irrationality.In order to accurately evaluate the water environment,it is particularly important to find an objective and universal water quality evaluation method.In this paper,based on the study of the existing water quality evaluation method,choose the fuzzy comprehensive evaluation method as the research object,using the cloud model to improve,make the new evaluation method of fusion processing fuzzy information and fuzzy comprehensive evaluation method of cloud model to deal with the uncertainty problem of advantage,strengthen the objective and scientific evaluation results,improve the efficiency of evaluation.After the applicability of cloud model in water environment is tested by normal distribution,the fuzzy comprehensive evaluation method based on cloud model is applied to water quality evaluation.The evaluation set composed of evaluation indexes was established,and the cloud model characteristic parameters corresponding to each water quality grade were calculated according to the water quality grading standards.Then,the forward cloud model was used to generate the standard cloud model of the evaluation set.X conditional cloud generator is used to generate the conditional cloud map of specific concentration value,and the evaluation index of specific concentration value is output to determine the distribution of the evaluation set.The membership matrix can be quickly calculated by modifying the input concentration value.According to the characteristics of dry season,wet season and normal season,weight is given by entropy method,and fuzzy vector is obtained by compound operation of membership matrix and weight.The fuzzy comprehensive evaluation method based on cloud model was used to evaluatethe water quality of 17 surface water monitoring sections in chengdu.The analysis results are as follows:1?The fuzzy comprehensive evaluation method based on cloud model and the fuzzy comprehensive evaluation method is better than single factor evaluation method is stable,and the evaluation result more accord with the actual situation of section,the fuzzy comprehensive evaluation method based on cloud model considering the effect of high concentration of pollution factors,the evaluation results with fuzzy comprehensive evaluation method is more accurate,and can reflect the different surface section water quality at the same level,realize the quantitative analysis of the five types of inferior quality water.2?Fuzzy comprehensive evaluation method based on cloud model,the water quality classification,reducing the loss of useful information and boundary values influence on evaluation results,with stable random number as a membership,fully considering the fuzziness and randomness in the subordinate relations,and the automatic generation of membership based on cloud model,simplified the calculating process,the operation is easier and faster and the evaluation results are more accurate.3?Analyze the evaluation results of surface water quality in chengdu by fuzzy comprehensive evaluation method based on cloud modelIn 2017,62.7% of the 17 surface monitoring sections in Chengdu were up to standard.,the overall water quality is light pollution,major pollution indicators for the total phosphorus,the water quality of cross section is the worst in dry season,and is better in normal season and high season.