酒后血液和呼气中乙醇含量的关系及数学模型建立

Relationship between Blood and Expiration Alcohol Concentration and Establishment of Mathematical Model

目的研究酒精呼气测定仪测得的呼气中乙醇含量(BrAC)与顶空气相色谱法(HS-GC)检测的血液乙醇含量(BAC)的关系,建立线性模型,以实现由BrAC对BAC的预测。方法选取2016年2—12月贵阳市涉嫌酒驾的53例健康驾驶员进行研究,检测BrAC与BAC,以BrAC为自变量(X),BAC为因变量(Y),绘制散点图,并建立线性模型。结果以BrAC与BAC数据拟合曲线得到曲线方程为Y=1.2982X-5.0175,R^2=0.95。采用简单随机抽样法抽取11个样本,用所得线性模型进行预测,并与样本实测值进行对比,预测值与实测值有较大偏差;去掉常数项,修改模型,得到曲线方程Y=1.2294X,R^2=0.99,2、3、8样本预测值与实测值相差较大,残差平方和(SSE)=621.70;对BAC取对数,得到线性方程:lnY=0.0166X+3.2185,R^2=0.93,预测值与实测值均相差不大,SSE=239.06。结论可以用lnY=0.0166X+3.2185模型来实现BrAC对BAC的预测。

Objective To study the relationship between concentration of alcohol in the exhaled breath at end-exhalation（ Br AC） determined by breathalyzer and blood alcohol concentration（ BAC） determined by HS-GC and to establish a linear model in order to achieve the prediction of BAC by Br AC. Methods From February to December in 2016,53 healthy drivers who were suspected of drunk driving in Guiyang were selected. The Br AC and BAC were determined. A scatter plot was drawn and a linear model was established with Br AC as the independent variable X and BAC as the dependent variable Y. Results The curve equation was obtained by fitting the data of Br AC and BAC： Y = 1. 298 2X-5. 017 5,R^2= 0. 95. A simple random sampling method was used to extract 11 samples. The linear model was used to predict the samples, and the results were compared with the samples＇ real values. The predicted values were in great deviation from the true ones. Removed the constant,modified the model,and got the curve equation： Y = 1. 229 4X, R^2= 0. 99. The predicted values of 2,3 and 8 samples differed greatly from the true values,and the sum of squared errors of prediction（ SSE） = 621. 70. Took the logarithm of BAC and got the linear equation： ln Y = 0. 016 6X ＋ 3. 218 5,R^2= 0. 93. There was little difference between the predicted and the true values,SSE = 239. 06. Conclusion The model ln Y = 0. 016 6X ＋ 3. 218 5 can be used to achieve the prediction of BAC by BrAC.