Matter Element Extension Evaluating Model Based on Synthesis Weights and Approach Degree and its Application

Based on analysis of former matter element extension evaluating model, author points out the former model´s limitation that the model can not be used when observed data are bigger than the section field value in evaluation of water quality. Combining synthesis weights with approach degree, a new matter element extension evaluating model based on synthesis weights and approach degree is established. The model effectively overcomes former model´s limitation in evaluation of water quality. In the model, synthesis weights formed by the whole diversity weights and the local diversity weights commendably show indexes´ influence to evaluating results. The model is applied in the practical example and the results show that it is scientific and reasonable.