Prediction of dissolved oxygen and ammonia nitrogen concentrations in aquaculture environment based on PCA and GA-LM
YAO Qi, MIAO Xinying
1.College of Information Engineering, Dalian Ocean University, Dalian 116023, China; 2.Key Laboratory of Ocean Information Technology of Liaoning Province, Dalian 116023, China
Abstract: To accurately predict two of the most important parameters, dissolved oxygen (DO) and ammonia nitrogen concentrations in aquaculture, aiming to solve the problems such as the determination of effective influence factors, prediction algorithm and network structure optimization, a prediction model of DO and ammonia nitrogen concentrations called GA-LM-PCA was proposed by combining the neural network (NN) algorithm of levenberg-marquardt (LM), genetic algorithm (GA) and principal component analysis (PCA). PCA was used to determine the influence factors which were decoupled and reduced in the dimension. The network architecture was optimized by GA for determination of the appropriate number of hidden layer nodes and weight values. LM was applied to train NN to improve the generalization ability and convergence speed. The performance of GA-LM-PCA was compared with that of GA-LM without PCA to verify the forecasting accuracy of the GA-LM-PCA, and the prediction effect of different quantity of influence factors was discussed. The comparison indicated that the predicted DO and ammonia nitrogen values using GA-LM-PCA were in good agreement with the measured data, with the mean absolute errors and the root mean square errors of 0.004 7, 1.872 7×10-4 (DO), and 0.006 5, 9.428 7×10-4 (ammonia nitrogen), indicating that GA-LM-PCA was more suitable for the occasion with a large number of influence factors. It is proved that the proposed model can be considered as an effective prediction tool for DO and ammonia nitrogen concentrations in aquaculture environment, especially for nonlinear systems with various complex factors.
姚启, 缪新颖. 基于主成分分析及GA-LM的水产养殖环境溶解氧和氨氮含量预测[J]. 大连海洋大学学报, 2021, 36(5): 851-858.
YAO Qi, MIAO Xinying. Prediction of dissolved oxygen and ammonia nitrogen concentrations in aquaculture environment based on PCA and GA-LM. Journal of Dalian Ocean University, 2021, 36(5): 851-858.