Research And Application Of Entropy In The Water System

The concept, theory and significant effect of entropy were introduced briefly in three phases, which were balance state, non-balance state and generalized state. The basic concept and character of information entropy were summarized in two cases that were discrete information source and continuous information source. Principle of Maximum Entropy (POME), the most important theorem of entropy, was interpreted.The state-of-the-art of the application of information entropy and POME in water system was reviewed in detail. The prospect study is also inquired as the remarks.The MEM1 (Maximum Entropy Method 1) spectral analysis was employed to detect the cryptic period of hydrologic time series. The annual runoff series, monthly runoff series, and maximum flood peak series of HuanYuan Kou in Yellow River were used to illustrate and validate this method.Based on the research on the component of hydrologic time series, The MEM1 spectral analysis was employed in the component disassembled forecasting method. The forecasting result of the annual runoff series, monthly runoff series, and maximum flood peak series of HuanYuan Kou in Yellow River were used to prove the validity and veracity of this method.For the first time, the progress in research technique of risk analysis in water system, and the state-of-the-art of its application were made an exhaustive study, which includes flood controlling and safety, water resources utilization, water conservancy project construction, groundwater and its pollution. The prospect study is also inquired as the remarks.For the first time, from mathematics approach, the prior probability distribution of risk analysis was derived by the use of POME in two cases that were discrete and continuous information source. The deriving of uniform distribution, normal-IV-distribution, and Pearson type III distribution by POME were taken as examples.For the first time, based on POME, two weighted generalized distances were defined to build up two fuzzy, which used relative membership degree, and optimal models for evaluation of water environment, considering both the randomness and the fuzziness. The validity and reliability of theory and models were proved out by the evaluation result of the eutrophication situations of 12 representative lakes (reservoirs) in China. Monte Carlo stochastic simulation method was used to evaluate and compare the models established and current model.For the first time, the basic concept and theory of Set Pair Analysis (SPA) as well as Fuzzy Set Theory (FST) were attempted to apply and developed in the evaluation of water environment. The generalized connexion entropy and the generalized relative membership degree were defined, in order to establish the one-level model based on SPA, and the two-level model based on SPA and FST for evaluation of water environment. The validity, simplicity and reliability of theory and model were proved out by the evaluation case.The theory and model proposed in this paper can be generalized and applied to other fields.