Department of Civil Engineering, Isfahan University of Technology, Isfahan, 8415683111, Iran.
Environ Monit Assess. 2018 Mar 22;190(4):239. doi: 10.1007/s10661-018-6608-4.
Using the multivariate statistical methods, this study interprets a set of data containing 23 water quality parameters from 10 quality monitoring stations in Karkheh River located in southwest of Iran over 5 years. According to cluster analysis, the stations are classified into three classes of quality, and the most important factors on the whole set of parameters and each class are determined by the help of factor analysis. The results indicate the effects of natural factors, soil weathering and erosion, urban and human wastewater, agricultural and industrial wastewater on water quality at different levels and any location. Afterwards, five input selection methods such as correlation model, principal component analysis, combination of gamma test and backward regression, gamma test and genetic algorithm, and gamma test by elimination method are used for modeling BOD, and then their efficiency is investigated in simulation BOD with local linear regression, Artificial Neural Network, and genetic programming. From five methods of input variables in BOD simulation by local linear regression, genetic test and backward regression with RMSE error of 0.27 are the best input methods; gamma test based on genetic algorithm is the best model in simulation by Artificial Neural Network with RMSE error of 0.28, and finally, the gamma test model based on genetic algorithm with RMSE error of 0.1303 is the most appropriate model in simulation with genetic programming.
本研究采用多元统计方法，解释了伊朗西南部卡尔克河 10 个水质监测站 5 年来采集的包含 23 个水质参数的一组数据。根据聚类分析，将监测站分为三类，通过因子分析确定了对整个参数集和每个类别的最重要因素。结果表明，自然因素、土壤风化和侵蚀、城市和人类废水、农业和工业废水对不同水平和位置的水质有影响。然后，使用相关模型、主成分分析、伽马检验与反向回归相结合、伽马检验与遗传算法、以及伽马检验消除法等五种输入选择方法对 BOD 进行建模，并通过局部线性回归、人工神经网络和遗传编程模拟 BOD 来研究其效率。在通过局部线性回归、遗传检验和反向回归的 BOD 模拟的五种输入变量方法中，RMSE 误差为 0.27 的方法是最佳输入方法；基于遗传算法的伽马检验是 RMSE 误差为 0.28 的人工神经网络模拟的最佳模型，最后，基于遗传算法的伽马检验模型 RMSE 误差为 0.1303，是遗传编程模拟的最合适模型。
