摘要
为提高珠江口水质预测精度和稳定性,提出了基于时间和特征双注意力机制优化的Bi LSTM水质预测模型,引入特征注意力机制强化模型捕获参数重要特征能力,加入时间注意力机制提高对时间序列相关性信息及水质波动细节信息的挖掘能力.将新模型应用于珠江8个入海口水质预测,开展预测性能试验、泛化能力试验和特征参数扩展性试验.结果表明:①新模型在珠海大桥水质预测取得了较高的预测精度,预测值与实测值的均方根误差RMSE为0.0041 mg·L^(-1),决定系数R^(2)为98.3%.与Multi-Bi LSTM、Multi-LSTM、Bi LSTM和LSTM对比,表明新模型预测精度最高,验证了模型的精准性.②训练样本数量和预测步数均对模型预测精度产生影响,模型预测精度随着训练样本的增加而提升,海珠大桥断面总磷预测时,240组以上训练样本可获得较高预测精度;增加预测步数,会使模型预测精度迅速下降,预测步数大于5步时无法保障模型预测的可靠性.③将新模型应用于珠江8个入海口不同水质指标预测,预测结果均取得较高精度,模型具有较强的泛化能力;输入对象断面预测指标相关联的上游来水、降雨量等特征参数,能够提高模型预测精度.通过多方面多次试验,结果表明新模型能够较好地满足珠江口水质预测精度、适用性和扩展性要求,为复杂水动力环境水体水质高精度预测进行了新的探索.
To improve the accuracy and stability of water quality prediction in the Pearl River Estuary,a water quality prediction model was proposed based on BiLSTM improved with an attention mechanism.The feature attention mechanism was introduced to enhance the ability of the model to capture important features,and the temporal attention mechanism was added to improve the mining ability of time series correlation information and water quality fluctuation details.The new model was applied to the water quality prediction of eight estuaries of the Pearl River,and the prediction performance test,generalization ability test,and characteristic parameter expansion test were carried out.The results showed that:①The new model achieved high prediction accuracy in the water quality prediction of the Zhuhaidaqiao section.The root-mean-square error(RMSE)between the predicted value and the measured value was 0.0041 mg·L^(-1),and the coefficient of determination(R^(2))was 98.3%.Compared with that of Multi-BiLSTM,Multi-LSTM,BiLSTM,and LSTM,the results showed that the new model had the highest prediction accuracy,which verified the accuracy of the model.②Both the number of training samples and the number of forecasting steps affected the prediction accuracy of the model,and the prediction accuracy of the model increased with the increase of the training samples.When predicting the total phosphorus of the Zhuhaidaqiao section,more than 240 training samples could obtain higher prediction accuracy.Increasing the number of prediction steps caused the prediction accuracy of the model to decline rapidly,and the reliability of the model prediction could not be guaranteed when the number of prediction steps was greater than 5.③When the new model was applied to the prediction of different water quality indexes in eight estuaries of the Pearl River,the prediction results had high precision and the model had strong generalization ability.The input data of upstream water quality,rainfall,and other characteristic parameters associated with the section prediction index of the object could improve the prediction accuracy of the model.Through many tests,the results showed that the new model could meet the requirements of precision,applicability,and expansibility of water quality prediction in the Pearl River Estuary and thus is a new exploration method for high-precision prediction of water quality in complex hydrodynamic environments.
作者
陈湛峰
李晓芳
CHEN Zhan-feng;LI Xiao-fang(Guangdong Ecological and Environmental Monitoring Center,Guangzhou 510308,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2024年第6期3205-3213,共9页
Environmental Science
基金
广东省重点领域研发计划项目(2020B1111350001)。
关键词
特征注意力机制
时间注意力机制
BiLSTM模型
LSTM模型
珠江口
水质预测
characteristic attention mechanism
temporal attention mechanism
BiLSTM model
LSTM model
Pearl River estuary
water quality prediction