Application and Sensitivity Analysis of Artificial Neural Network for Prediction of Chemical Oxygen Demand

Integrating water quality forecasting model with river restoration techniques makes river restoration more effective and efficient. This research investigates how to use the Artificial Neural Network (ANN) to predict the Chemical Oxygen Demand (COD) during river restoration in Wuxi city, China. Specifically, we applied a Multi-Layer Perceptron (MLP) using ten neurons in a single hidden layer and seven input variables (Temperature, Dissolved Oxygen, Total Nitrogen, Total Phosphorus, Suspended Sediment, Transparency, and NH3-N) to simulate COD. The modeled results have a correlation coefficient of 0.966, 0.949, and 0.890 with the observations for the raining, validation, and testing phases, respectively. When presenting the trained network to an independent data set, the ANN model still shows a good predictive capability, indicating by a correlation coefficient of 0.978, a root mean square error (RMSE) of 0.628 mg/L, and a mean square error (MSE) of 0.394 mg2/L2. A sensitivity analysis was further implemented to analyze the effect of each of the input variables on prediction of COD. DO, TO, and Transparency have relatively low influences on the estimate of COD, and can be removed from the input variables. The results from this study indicate that ANN models can provide satisfactory estimates of COD during the process of bacterial treatment and is a useful supportive tool for river restoration.

[1]  J. Nazuno Haykin, Simon. Neural networks: A comprehensive foundation, Prentice Hall, Inc. Segunda Edición, 1999 , 2000 .

[2]  The Using Artificial Neural Network to Estimate of Chemical Oxygen Demand , 2013 .

[4]  Laurene V. Fausett,et al.  Fundamentals Of Neural Networks , 1993 .

[6]  Ahmed El-Shafie,et al.  Optimized Neural Network Prediction Model for Potential Evapotranspiration Utilizing Ensemble Procedure , 2014, Water Resources Management.

[7]  Paresh Chandra Deka,et al.  Effects of Data Pre-processing on the Prediction Accuracy of Artificial Neural Network Model in Hydrological Time Series , 2016 .

[8]  Chuanqi Zhang,et al.  Artificial neural network modeling of dissolved oxygen in the Heihe River, Northwestern China , 2013, Environmental Monitoring and Assessment.

[9]  T. Ishikawa,et al.  New Approach for Estimation of Pollutant Load by Using Artificial Neural Network , 2009 .

[10]  P. J. García Nieto,et al.  Turbidity Prediction in a River Basin by Using Artificial Neural Networks: A Case Study in Northern Spain , 2013, Water Resources Management.

[11]  K. P. Sudheer,et al.  Methods used for the development of neural networks for the prediction of water resource variables in river systems: Current status and future directions , 2010, Environ. Model. Softw..

[12]  Jasna Radulović,et al.  Neural network modeling of dissolved oxygen in the Gruža reservoir, Serbia , 2010 .

[13]  Xianjin Huang,et al.  Spatial Autocorrelation Analysis of Chinese Inter-Provincial Industrial Chemical Oxygen Demand Discharge , 2012, International journal of environmental research and public health.

[14]  B A Cox,et al.  A review of dissolved oxygen modelling techniques for lowland rivers. , 2003, The Science of the total environment.

[15]  Ali Rahimikhoob,et al.  Comparison between M5 Model Tree and Neural Networks for Estimating Reference Evapotranspiration in an Arid Environment , 2014, Water Resources Management.

[16]  Ashantha Goonetilleke,et al.  Water Resources Management: Innovation and Challenges in a Changing World , 2017 .

[17]  Feasibility of Bacterial Technology for Treating a Polluted Urban Streams from the Perspective of Numerical Modelling , 2010 .

[18]  Min Shao,et al.  City clusters in China: air and surface water pollution , 2006 .

[19]  G. Ayzel,et al.  Runoff evaluation for ungauged watersheds by SWAP model. 1. Application of artificial neural networks , 2017, Water Resources.

[20]  Kulwinder Singh Parmar,et al.  River Water Prediction Modeling Using Neural Networks, Fuzzy and Wavelet Coupled Model , 2014, Water Resources Management.

[21]  Junsong Jia,et al.  Multi-Perspectives’ Comparisons and Mitigating Implications for the COD and NH3-N Discharges into the Wastewater from the Industrial Sector of China , 2017 .