Improved comprehensive water quality identification index algorithm and its application

Comprehensive water quality identification index algorithm can not only qualitatively but also quantitatively evaluate a river´s comprehensive water quality,the weight of every identification index has great effect to the identification result. So, comprehensive determining weights methods is imported to get every index´s weight. Firstly, subjective weight and objective weight algorithm are used to determine subjective and objective weight vectors,after that arithmetic average value method is used to colligate them, then the comprehensive weight of each index is obtained, which can more objectively reflect every index´s function in the water quality comprehensive evaluation. This algorithm is applied to evaluate the water quality in the engineering of water resources uses of Wen-Yu river located at Shun Yi in BeiJing. The evaluation result is reasonable and reliable.