基于GRU和XGBoost的矿压显现规律预测

采用光纤传感器监测的光纤频移值对矿压显现规律进行表征的过程中,传感器采集的数据存在缺失现象,无法准确预测矿压显现规律。针对该问题,以千秋煤矿为工程背景,在假设光纤下半部分数据丢失的前提下,引入GRU(门控循环单元)和LSTM(长短期记忆网络)2种预测模型,对缺失的光纤频移值进行对比预测,得出GRU模型的收敛速度优于LSTM模型的收敛速度,说明基于GRU模型的缺失值处理方法较优。将原始完整的光纤频移值转换为可表征矿压显现位置的光纤平均频移变化度,引入XGBoost(极端梯度提升)模型和BP神经网络模型进行对比预测,XGBoost模型能准确预测出测试集中所有出现“尖峰”的位置,而BP神经网络模型只预测出2处“尖峰”位置,说明XGBoost模型的预测效果优于BP神经网络模型的预测效果。将预测出的光纤频移缺失值替换至缺失位置,形成“完整”光纤频移值数据,将该数据转换为光纤平均频移变化度后,采用XGBoost模型进行预测。验证结果表明:LSTM模型及GRU模型均可准确预测出光纤下半部分的数据,且GRU模型准确性较LSTM模型准确性高;使用XGBoost可准确预测出测试集中出现的周期来压;通过GRU模型预测出的缺失数据经整合至缺失位置后,使用XGBoost模型仍可进行有效的矿压预测。

Prediction of strata behaviors law based on GRU and XGBoost

In the process of using optical fiber frequency shift value monitored by optical fiber sensor to characterize the strata behaviors law,the data collected by the sensor is missing,and the strata behaviors law can not be accurately predicted.In order to solve this problem,taking Qianqiu Coal Mine as the engineering background,under the premise of partial data loss of the lower half of the optical fiber,two prediction models,GRU(Gated Recurrent Unit)and LSTM(Long Short-Term Memory),are introduced to compare and predict the missing optical fiber frequency shift value.The convergence speed of the GRU model is better than that of the LSTM model,which shows that the missing value processing method based on the GRU model is better.The original and complete optical fiber frequency shift value is converted into the average optical fiber frequency shift change which can characterize the strata behaviors position,and the XGBoost(eXtreme Gradient Boosting)model and the BP neural network model are introduced for comparative prediction.The XGBoost model can predict all the'peak'positions in the test set accurately.However,the BP neural network model can only predict two'peak'positions,which shows that the prediction effect of the XGBoost model is better than that of the BP neural network model.The predicted optical fiber frequency shift missing value is replaced to the missing position to form'complete'optical fiber frequency shift value data.The data is converted into the average optical fiber frequency shift change and then the XGBoost model is used for prediction.The results show that both the LSTM model and the GRU model can predict the data of the lower half of the optical fiber accurately,and the GRU model has higher accuracy than the LSTM model.The XGBoost model can predict the periodic pressure in the test set accurately.After the missing data predicted by the GRU model is integrated into the missing position,the XGBoost model can still predict the strata behaviors effectively.