Time Series Prediction Method of Clean Coal Ash Content in Dense Medium Separation Based on the Improved EMD-LSTM Model
Abstract
1. Introduction
2. Literature Review
3. Research Methodology and Procedure
3.1. Research Methodology
3.1.1. EMD
3.1.2. LSTM
3.2. Framework of Prediction Methodology
3.3. Construction Process of Prediction Methodology
3.3.1. EMD of Time Series Signal
- (i)
- The number of extrema (sum of the number of maxima and minima) must be equal to or differ by at most one from the number of zero crossings.
- (ii)
- The mean of envelopes defined by the local maxima and minima should be zero at any point of the IMF.
3.3.2. LSTM Prediction for Each Component
3.3.3. Selective Reconstruction of Each Prediction Component
3.4. Structural Diagram of Prediction Methodology
4. Results and Analysis
4.1. Evaluation Metrics
4.2. EMD Results
4.3. LSTM Prediction of Time Series Component
4.3.1. Experimental Setup
4.3.2. Prediction Results
- (1)
- Results of the error metric
- (2)
- Results of the VVRD metric
- (3)
- Comprehensive results
4.4. Analysis of Model Selection
4.5. Parameter Optimization for the EMD-imf1-LSTM Model
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Frequency Band | Threshold | Range |
---|---|---|
Low Frequency | 10 30 | F ≤ 10 |
Middle Frequency | 10 < F ≤ 30 | |
High Frequency | 30 < F |
Model | EMD-imf1-LSTM | EMD-imf1-LSTM-SSA | |
---|---|---|---|
Valuation Metrics | |||
RMSE | 0.01014 | 0.0099389 | |
MAE | 0.00884 | 0.0051748 | |
MAPE | 0.0806% | 0.04720% | |
NSD | 11 | 12 |
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Cheng, K.; Zhang, X.; Zhou, K.; Zhou, C.; Li, J.; Yang, C.; Guo, Y.; Wang, R. Time Series Prediction Method of Clean Coal Ash Content in Dense Medium Separation Based on the Improved EMD-LSTM Model. Big Data Cogn. Comput. 2025, 9, 159. https://doi.org/10.3390/bdcc9060159
Cheng K, Zhang X, Zhou K, Zhou C, Li J, Yang C, Guo Y, Wang R. Time Series Prediction Method of Clean Coal Ash Content in Dense Medium Separation Based on the Improved EMD-LSTM Model. Big Data and Cognitive Computing. 2025; 9(6):159. https://doi.org/10.3390/bdcc9060159
Chicago/Turabian StyleCheng, Kai, Xiaokang Zhang, Keping Zhou, Chenao Zhou, Jielin Li, Chun Yang, Yurong Guo, and Ranfeng Wang. 2025. "Time Series Prediction Method of Clean Coal Ash Content in Dense Medium Separation Based on the Improved EMD-LSTM Model" Big Data and Cognitive Computing 9, no. 6: 159. https://doi.org/10.3390/bdcc9060159
APA StyleCheng, K., Zhang, X., Zhou, K., Zhou, C., Li, J., Yang, C., Guo, Y., & Wang, R. (2025). Time Series Prediction Method of Clean Coal Ash Content in Dense Medium Separation Based on the Improved EMD-LSTM Model. Big Data and Cognitive Computing, 9(6), 159. https://doi.org/10.3390/bdcc9060159