2013美赛b题2013美赛b题.doc

Water, Water, Everywhere Summary Water is extremely important subsistence, while closely related to the political, economic and cultural development, Beijing is one of the worlds metropolis severe water shortage. Taking Beijing as an example, for water scarcity factor, the mathematical model by finding authoritative data reveals the relationship between water scarcity and related factors, and the use of water shortage risk assessment model for effective regulation of water shortages. Firstly, the composition of water resources derived factors. The main discussion from the total water resources (water supply) and total water consumption (water demand) in two ways. Factors affecting the total water resources of surface water from the start, groundwater and wastewater treatment capacity. Factors that affect the total amount of water from agricultural water, industrial water, industrial and domestic water to start the third specific analysis. Secondly, Richard was in Beijing 2001-2008 water data, using multiple linear regression, to establish the total amount of water and surface water, groundwater and sewage treatment capacity of the linear regression equation y?=-4.732+2.138x1+0.498x2+0.274x3 Again, the use of gray correlation to determine agricultural water, industrial water, industrial and domestic water consumption associated with the third degree and total water consumption ra=0.369852，rb= 0.369167，rc=0.260981 ,To determine their risk of significant rarbrc. Then again, the use of the data curve fitting functions between agriculture, industry and tertiary industry and domestic water consumption and between years a=0.0019（t-1994）3-0.0383（t-1994）2-0.4332（t-1994）+20.2598; b=0.014（t-1994）2-0.8261t+14.1337; c=0.0383（t-1994）2-0.097（t-1994）+11.2116; D=a+b+c Predict the amount of water 2009-2012 A final prediction, defined by the degree of water S = (Dy) / D = 1-y / D, 1994-2008 calculated degree of water drawn out of the histogram, dividing the risk level. We take many ye