长江水质的评价预测模型

The Model of Evaluation and Forecast for Yangtse River's Water Quality

本问题是一个对长江的水质进行综合评价、预测和控制的问题。首先对各项数据做归一化处理;再建立变权函数,确定四项水质指标的污染权值,进行动态加权,根据水质污染的指标对长江17个观测站每个月的水质排序;再用决策分析方法中的Borda法对28个月进行水质综合排序。先假定排污口分别位于江段上游和下游的情况下,取均值作为江段单位时间排污量。在对长江未来水质污染的发展趋势作预测时,通过可饮用水(Ⅰ类、Ⅱ类、Ⅲ类)和污染水(Ⅳ类、Ⅴ类)的比例变化来进行分析,建立排污量与时间的灰色预测模型,得出未来10年的排污量。建立可饮用水和污染水与总流量和排污量的二元线性回归预测模型,从得到的结果看,可饮用水的比例逐年减少,水污染愈来愈严重。关于未来10年污水处理量,主要在问题3的基础上,得出长江的极限载污量,与预测排污量相减,求得每年需要的污水量。

This issue focuses on making synthetical evaluation, calculation and controlling to Yangtse River＇s water quality. Firstly, disposing of all data into one category, then establishing changeable value function, and defining the pollution value of four items water quality indexes. We carry on dynamic additional power and putting the water quality each month in oder which about Yangtse River＇s seventeen observatories according to the indexes of water quality pollution. While calculating the development trend to twenty-eight months water pollution through Borda method of decision-analysis methodology, making analyze to the proportion change between drinking water （ Ⅰ Ⅱ Ⅲcategory） and sewage （Ⅳ Ⅴ category） and establishing the weather calculation pattern of discharge sewage volume and time, to get the discharge sewage volume of the future ten years, also we build the secondary gender regression calculation pattern about drinking water and sewage with total volume and discharge sewage volume. The results showed that, the drinking water＇s proportion decreased year after year and water pollution became more and more serious. Concerning the sewage treatment volume in the ten years future, we can get the limited sewage volume of Yangtse River on the basis of the questoin Three and subtract calculation sewage volume to defin.