Accurate prediction of rockburst intensity levels is crucial for ensuring the safety of deep hard rock engineering construction.This paper introduced an expert system for rockburst intensity level prediction that empl...Accurate prediction of rockburst intensity levels is crucial for ensuring the safety of deep hard rock engineering construction.This paper introduced an expert system for rockburst intensity level prediction that employs machine learning algorithms as the basis for its inference rules.The system comprises four modules:a database,a repository,an inference engine,and an interpreter.A database containing 1114 rockburst cases was used to construct 357 datasets that serve as the repository for the expert system.Additionally,19 types of machine learning algorithms were used to establish 6783 micro-models to construct cognitive rules within the inference engine.By integrating probability theory and marginal analysis,a fuzzy scoring method based on the SoftMax function was developed and applied to the interpreter for rockburst intensity level prediction,effectively restoring the continuity of rockburst characteristics.The research results indicate that ensemble algorithms based on decision trees are more effective in capturing the characteristics of rockburst.Key factors for accurate prediction of rockburst intensity include uniaxial compressive strength,elastic energy index,the maximum principal stress,tangential stress,and their composite indicators.The accuracy of the proposed rockburst intensity level prediction expert system was verified using 20 engineering rockburst cases,with predictions aligning closely with the actual rockburst intensity levels.展开更多
In this study,convolutional long short-term memory(ConvLSTM)model is used to predict sea level anomaly(SLA)in the Kuroshio Extension(KE)region,utilizing daily satellite altimetry data(1993-2016).The model captures reg...In this study,convolutional long short-term memory(ConvLSTM)model is used to predict sea level anomaly(SLA)in the Kuroshio Extension(KE)region,utilizing daily satellite altimetry data(1993-2016).The model captures regional averaged SLA variability,achieving a correlation coefficient of 0.98 for prediction horizon up to 23 d.Propagating features of Rossby waves are also reproduced in the prediction model.While in spatial,discrepancies between predicted SLA and observed SLA are quite large,especially in regions with strong eddy activities.Incorporating equation of motion for the 11/2-layer reduced-gravity model,the performance of the model has a significant improvement spatially and temporally.Challenges persist in high-variability regions,underscoring the need for advanced models.This study highlights ConvLSTM’s potential for SLA forecasting with wind driven physical constraints,offering insights into wind-driven and eddy-influenced processes in the KE region.展开更多
In the context of global change,understanding changes in water resources requires close monitoring of groundwater levels.A mismatch between water supply and demand could lead to severe consequences such as land subsid...In the context of global change,understanding changes in water resources requires close monitoring of groundwater levels.A mismatch between water supply and demand could lead to severe consequences such as land subsidence.To ensure a sustainable water supply and to minimize the environmental effects of land subsidence,groundwater must be effectively monitored and managed.Despite significant global progress in groundwater management,the swift advancements in technology and artificial intelligence(AI)have spurred extensive studies aimed at enhancing the accuracy of groundwater predictions.This study proposes an AI-based method that combines deep learning with a cloud-supported data processing workflow.The method utilizes river level data from the Zhuoshui River alluvial fan area in Taiwan,China to forecast groundwater level fluctuations.A hybrid imputation scheme is applied to reduce data errors and improve input continuity,including Z-score anomaly detection,sliding window segmentation,and STL-SARIMA-based imputation.The prediction model employs the BiLSTM model combined with the Bayesian optimization algorithm,achieving an R2 of 0.9932 and consistently lower MSE values than those of the LSTM and RNN models across all experiments.Specifically,BiLSTM reduces MSE by 62.9%compared to LSTM and 72.6%compared to RNN,while also achieving the lowest MAE and MAPE scores,demonstrating its superior accuracy and robustness in groundwater level forecasting.This predictive advantage stems from the integration of a hybrid statistical imputation process with a BiLSTM model optimized through Bayesian search.These components collectively enable a reliable and integrated forecasting system that effectively models groundwater level variations,thereby providing a practical solution for groundwater monitoring and sustainable water resource management.展开更多
Time-series water level prediction during natural disasters,for example,typhoons and storms,is crucial for both flood control and prevention.Utilizing data-driven models that harness deep learning(DL)techniques has em...Time-series water level prediction during natural disasters,for example,typhoons and storms,is crucial for both flood control and prevention.Utilizing data-driven models that harness deep learning(DL)techniques has emerged as an attractive and effective approach to water level prediction.This paper proposed an innovative data-driven methodology using DL network architectures of Gated Recurrent Unit(GRU),Long Short-Term Memory(LSTM),and Bidirectional Long-Short Term Memory(Bi-LSTM)to predict the water level at the Le Thuy station in the Kien Giang River.These models were implemented and validated based on hourly rainfall and water level observations at meteo-hydrological stations.Three combinations of input variables with different time leads and time lags were established to evaluate the forecast capability of three proposed models by using five metrics,that is,R2,MAE,RMSE,Max Error Value,and Max Error Time.The results revealed that the LSTM model outperformed the Bi-LSTM and GRU models,when water level and rainfall observations for one-time lag at three stations were used to predict the water level at the Le Thuy station with 1-h time lead,with the five metrics registering at 0.999;3.6 cm;2.6 cm;12.9 cm;and−1 h,respectively.展开更多
High-accuracy Sea level prediction is important for understanding marine environments and climate change.In this work,a deep convolutional neural network(CNN)combined with attention mechanism(ADNN)is established for s...High-accuracy Sea level prediction is important for understanding marine environments and climate change.In this work,a deep convolutional neural network(CNN)combined with attention mechanism(ADNN)is established for sea level anomaly(SLA)prediction from historical satellite observations.Multi-year(1998-2020)radar altimetry observed SLA pattern samples in the South China Sea are used for model training and testing.Compared with existing deep learning models such as CNN and convolutional long short-term memory(ConvLSTM)network,ADNN demonstrates the highest accuracies of 94.0%,91.1%,88.4%and 86.2%for 1-d,3-d,5-d and 7-d SLA field predictions,with regional average root mean square errors(RMSE)of 0.27 cm,0.51 cm,0.80 cm and 1.09 cm,respectively.The integration of CNN and attention mechanism significantly improves the model performance,especially in estimating short-term sea level changes,with a 74.7%reduction in the RMSE for 1-d predictions compared to the baseline CNN model.Comparative experiments also show that the ADNN model performs well when the input data contains a certain degree of noise.Moreover,a multivariate ADNN(M-ADNN)model is designed to investigate the impacts of environmental variables such as sea surface temperature(SST)and wind on SLA prediction.The model yields a slightly higher accuracy but the results are quite similar to those of the ADNN model.The findings suggest that,although SST or wind can affect sea level changes,the ADNN model demonstrates the ability to identify and learn sufficient information about sea level changes solely from satellite altimetry measurements of SLA,especially for relatively long-term(≥5 d)predictions.This eliminates the need for additional input parameter data,thereby improving the SLA prediction efficiency.展开更多
An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variat...An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variation of the tidal level is a time-varying process. The time-varying factors including interference from the external environment that cause the change of tides are fairly complicated. Furthermore, tidal variations are affected not only by periodic movement of celestial bodies but also by time-varying interference from the external environment. Consequently, for the efficient and precise tidal level prediction, a neuro-fuzzy hybrid technology based on the combination of harmonic analysis and adaptive network-based fuzzy inference system（ANFIS）model is utilized to construct a precise tidal level prediction system, which takes both advantages of the harmonic analysis method and the ANFIS network. The proposed prediction model is composed of two modules： the astronomical tide module caused by celestial bodies’ movement and the non-astronomical tide module caused by various meteorological and other environmental factors. To generate a fuzzy inference system（FIS） structure,three approaches which include grid partition（GP）, fuzzy c-means（FCM） and sub-clustering（SC） are used in the ANFIS network constructing process. Furthermore, to obtain the optimal ANFIS based prediction model, large numbers of simulation experiments are implemented for each FIS generating approach. In this tidal prediction study, the optimal ANFIS model is used to predict the non-astronomical tide module, while the conventional harmonic analysis model is used to predict the astronomical tide module. The final prediction result is performed by combining the estimation outputs of the harmonious analysis model and the optimal ANFIS model. To demonstrate the applicability and capability of the proposed novel prediction model, measured tidal level samples of Fort Pulaski tidal station are selected as the testing database. Simulation and experimental results confirm that the proposed prediction approach can achieve precise predictions for the tidal level with high accuracy, satisfactory convergence and stability.展开更多
An explicit model management framework is introduced for predictive Groundwater Levels(GWL),particularly suitable to Observation Wells(OWs)with sparse and possibly heterogeneous data.The framework implements Multiple ...An explicit model management framework is introduced for predictive Groundwater Levels(GWL),particularly suitable to Observation Wells(OWs)with sparse and possibly heterogeneous data.The framework implements Multiple Models(MM)under the architecture of organising them at levels,as follows:(i)Level 0:treat heterogeneity in the data,e.g.Self-Organised Mapping(SOM)to classify the OWs;and decide on model structure,e.g.formulate a grey box model to predict GWLs.(ii)Level 1:construct MMs,e.g.two Fuzzy Logic(FL)and one Neurofuzzy(NF)models.(iii)Level 2:formulate strategies to combine the MM at Level 1,for which the paper uses Artificial Neural Networks(Strategy 1)and simple averaging(Strategy 2).Whilst the above model management strategy is novel,a critical view is presented,according to which modelling practices are:Inclusive Multiple Modelling(IMM)practices contrasted with existing practices,branded by the paper as Exclusionary Multiple Modelling(EMM).Scientific thinking over IMMs is captured as a framework with four dimensions:Model Reuse(MR),Hierarchical Recursion(HR),Elastic Learning Environment(ELE)and Goal Orientation(GO)and these together make the acronym of RHEO.Therefore,IMM-RHEO is piloted in the aquifer of Tabriz Plain with sparse and possibly heterogeneous data.The results provide some evidence that(i)IMM at two levels improves on the accuracy of individual models;and(ii)model combinations in IMM practices bring‘model-learning’into fashion for learning with the goal to explain baseline conditions and impacts of subsequent management changes.展开更多
An improved method using kernel density estimation （KDE） and confidence level is presented for model validation with small samples. Decision making is a challenging problem because of input uncertainty and only smal...An improved method using kernel density estimation （KDE） and confidence level is presented for model validation with small samples. Decision making is a challenging problem because of input uncertainty and only small samples can be used due to the high costs of experimental measurements. However, model validation provides more confidence for decision makers when improving prediction accuracy at the same time. The confidence level method is introduced and the optimum sample variance is determined using a new method in kernel density estimation to increase the credibility of model validation. As a numerical example, the static frame model validation challenge problem presented by Sandia National Laboratories has been chosen. The optimum bandwidth is selected in kernel density estimation in order to build the probability model based on the calibration data. The model assessment is achieved using validation and accreditation experimental data respectively based on the probability model. Finally, the target structure prediction is performed using validated model, which are consistent with the results obtained by other researchers. The results demonstrate that the method using the improved confidence level and kernel density estimation is an effective approach to solve the model validation problem with small samples.展开更多
Nowadays, the deep learning methods are widely applied to analyze and predict the trend of various disaster events and offer the alternatives to make the appropriate decisions. These support the water resource managem...Nowadays, the deep learning methods are widely applied to analyze and predict the trend of various disaster events and offer the alternatives to make the appropriate decisions. These support the water resource management and the short-term planning. In this paper, the water levels of the Pattani River in the Southern of Thailand have been predicted every hour of 7 days forecast. Time Series Transformer and Linear Regression were applied in this work. The results of both were the water levels forecast that had the high accuracy. Moreover, the water levels forecasting dashboard was developed for using to monitor the water levels at the Pattani River as well.展开更多
Maintaining high groundwater level(GWL)is important for preventing fires in peatlands.This study proposes GWL prediction using machine learning methods for forest plantations in Indonesian tropical peatlands.Deep neur...Maintaining high groundwater level(GWL)is important for preventing fires in peatlands.This study proposes GWL prediction using machine learning methods for forest plantations in Indonesian tropical peatlands.Deep neural networks(DNN)have been used for prediction;however,they have not been applied to groundwater prediction in Indonesian peatlands.Tropical peatland is characterized by high permeability and forest plantations are surrounded by several canals.By predicting daily differences in GWL,the GWL can be predicted with high accuracy.DNNs,random forests,support vector regression,and XGBoost were compared,all of which indicated similar errors.The SHAP value revealed that the precipitation falling on the hill rapidly seeps into the soil and flows into the canals,which agrees with the fact that the soil has high permeability.These findings can potentially be used to alleviate and manage future fires in peatlands.展开更多
The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multi...The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multienergy complementary ways.Focusing on the regional integrated energy system composed of electrical microgrid and natural gas network,a fault risk warning method based on the improved RelieF-softmax method is proposed in this paper.The raw data-set was first clustered by the K-maxmin method to improve the preference of the random sampling process in the RelieF algorithm,and thereby achieved a hierarchical and non-repeated sampling.Then,the improved RelieF algorithm is used to identify the feature vectors,calculate the feature weights,and select the preferred feature subset according to the initially set threshold.In addition,a correlation coefficient method is applied to reduce the feature subset,and further eliminate the redundant feature vectors to obtain the optimal feature subset.Finally,the softmax classifier is used to obtain the early warnings of the integrated energy system.Case studies are conducted on an integrated energy system in the south of China to demonstrate the accuracy of fault risk warning method proposed in this paper.展开更多
The prediction of groundwater level is important for the use and management of groundwater resources. In this paper, the artificial neural networks (ANN) were used to predict groundwater level in the Dawu Aquifer of ...The prediction of groundwater level is important for the use and management of groundwater resources. In this paper, the artificial neural networks (ANN) were used to predict groundwater level in the Dawu Aquifer of Zibo in Eastern China. The first step was an auto-correlation analysis of the groundwater level which showed that the monthly groundwater level was time dependent. An auto-regression type ANN (ARANN) model and a regression-auto-regression type ANN (RARANN) model using back-propagation algorithm were then used to predict the groundwater level. Monthly data from June 1988 to May 1998 was used for the network training and testing. The results show that the RARANN model is more reliable than the ARANN model, especially in the testing period, which indicates that the RARANN model can describe the relationship between the groundwater fluctuation and main factors that currently influence the groundwater level. The results suggest that the model is suitable for predicting groundwater level fluctuations in this area for similar conditions in the future.展开更多
This study explores the potential of the advanced selective state spaces model(SSSM)in modeling complicated process industries system and proposes the process industry state identification model(PISIM)for controlled p...This study explores the potential of the advanced selective state spaces model(SSSM)in modeling complicated process industries system and proposes the process industry state identification model(PISIM)for controlled prediction of flotation cell pulp level.As a neural system identification model,the PISIM inherits two advantages of the SSSM to address the challenges in identifying flotation systems,including modeling the impact of frequent upstream fluctuations on system states,complex nonlinear physicochemical processes,and long-term dependencies.The first advantage is the ability to capture long-range dependencies,thereby boosting its long-term predictive accuracy.The second lies in the model structure adhering to scaling laws,enabling ongoing enhancements in performance as datasets expand.PISIM is evaluated using a real industrial dataset from a flotation plant at a copper mine in Zambia,with the results demonstrating its theoretical advantages.In a 4.5-hour pulp level prediction task,PISIM outperforms the baseline model by more than 31.34%.Furthermore,a flotation process control simulation experimental system based on PISIM is developed and deployed in a flotation plant in Zambia,assisting engineers in evaluating and optimizing setpoint strategies,ensuring stable production and improving production efficiency.展开更多
The prosperity of deep learning has revolutionized many machine learning tasks(such as image recognition,natural language processing,etc.).With the widespread use of autonomous sensor networks,the Internet of Things,a...The prosperity of deep learning has revolutionized many machine learning tasks(such as image recognition,natural language processing,etc.).With the widespread use of autonomous sensor networks,the Internet of Things,and crowd sourcing to monitor real-world processes,the volume,diversity,and veracity of spatial-temporal data are expanding rapidly.However,traditional methods have their limitation in coping with spatial-temporal dependencies,which either incorporate too much data from weakly connected locations or ignore the relationships between those interrelated but geographically separated regions.In this paper,a novel deep learning model(termed RF-GWN)is proposed by combining Random Forest(RF)and Graph WaveNet(GWN).In RF-GWN,a new adaptive weight matrix is formulated by combining Variable Importance Measure(VIM)of RF with the long time series feature extraction ability of GWN in order to capture potential spatial dependencies and extract long-term dependencies from the input data.Furthermore,two experiments are conducted on two real-world datasets with the purpose of predicting traffic flow and groundwater level.Baseline models are implemented by Diffusion Convolutional Recurrent Neural Network(DCRNN),Spatial-Temporal GCN(ST-GCN),and GWN to verify the effectiveness of the RF-GWN.The Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and Mean Absolute Percentage Error(MAPE)are selected as performance criteria.The results show that the proposed model can better capture the spatial-temporal relationships,the prediction performance on the METR-LA dataset is slightly improved,and the index of the prediction task on the PEMS-BAY dataset is significantly improved.These improvements are extended to the groundwater dataset,which can effectively improve the prediction accuracy.Thus,the applicability and effectiveness of the proposed model RF-GWN in both traffic flow and groundwater level prediction are demonstrated.展开更多
基金Project(42077244)supported by the National Natural Science Foundation of ChinaProject(2020-05)supported by the Open Research Fund of Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization,China。
文摘Accurate prediction of rockburst intensity levels is crucial for ensuring the safety of deep hard rock engineering construction.This paper introduced an expert system for rockburst intensity level prediction that employs machine learning algorithms as the basis for its inference rules.The system comprises four modules:a database,a repository,an inference engine,and an interpreter.A database containing 1114 rockburst cases was used to construct 357 datasets that serve as the repository for the expert system.Additionally,19 types of machine learning algorithms were used to establish 6783 micro-models to construct cognitive rules within the inference engine.By integrating probability theory and marginal analysis,a fuzzy scoring method based on the SoftMax function was developed and applied to the interpreter for rockburst intensity level prediction,effectively restoring the continuity of rockburst characteristics.The research results indicate that ensemble algorithms based on decision trees are more effective in capturing the characteristics of rockburst.Key factors for accurate prediction of rockburst intensity include uniaxial compressive strength,elastic energy index,the maximum principal stress,tangential stress,and their composite indicators.The accuracy of the proposed rockburst intensity level prediction expert system was verified using 20 engineering rockburst cases,with predictions aligning closely with the actual rockburst intensity levels.
基金The National Natural Science Foundation of China under contract No.42276014Jiangsu Natural Resources Development Special Fund(Marine Science and Technology Innovation)under contract No.JSZRKJ202403.
文摘In this study,convolutional long short-term memory(ConvLSTM)model is used to predict sea level anomaly(SLA)in the Kuroshio Extension(KE)region,utilizing daily satellite altimetry data(1993-2016).The model captures regional averaged SLA variability,achieving a correlation coefficient of 0.98 for prediction horizon up to 23 d.Propagating features of Rossby waves are also reproduced in the prediction model.While in spatial,discrepancies between predicted SLA and observed SLA are quite large,especially in regions with strong eddy activities.Incorporating equation of motion for the 11/2-layer reduced-gravity model,the performance of the model has a significant improvement spatially and temporally.Challenges persist in high-variability regions,underscoring the need for advanced models.This study highlights ConvLSTM’s potential for SLA forecasting with wind driven physical constraints,offering insights into wind-driven and eddy-influenced processes in the KE region.
文摘In the context of global change,understanding changes in water resources requires close monitoring of groundwater levels.A mismatch between water supply and demand could lead to severe consequences such as land subsidence.To ensure a sustainable water supply and to minimize the environmental effects of land subsidence,groundwater must be effectively monitored and managed.Despite significant global progress in groundwater management,the swift advancements in technology and artificial intelligence(AI)have spurred extensive studies aimed at enhancing the accuracy of groundwater predictions.This study proposes an AI-based method that combines deep learning with a cloud-supported data processing workflow.The method utilizes river level data from the Zhuoshui River alluvial fan area in Taiwan,China to forecast groundwater level fluctuations.A hybrid imputation scheme is applied to reduce data errors and improve input continuity,including Z-score anomaly detection,sliding window segmentation,and STL-SARIMA-based imputation.The prediction model employs the BiLSTM model combined with the Bayesian optimization algorithm,achieving an R2 of 0.9932 and consistently lower MSE values than those of the LSTM and RNN models across all experiments.Specifically,BiLSTM reduces MSE by 62.9%compared to LSTM and 72.6%compared to RNN,while also achieving the lowest MAE and MAPE scores,demonstrating its superior accuracy and robustness in groundwater level forecasting.This predictive advantage stems from the integration of a hybrid statistical imputation process with a BiLSTM model optimized through Bayesian search.These components collectively enable a reliable and integrated forecasting system that effectively models groundwater level variations,thereby providing a practical solution for groundwater monitoring and sustainable water resource management.
基金Scientific Research and Technology Development Project under Viet Nam Ministry of Agriculture and Rural Development,Grant/Award Number:09/HĐĐHTL-PCTT。
文摘Time-series water level prediction during natural disasters,for example,typhoons and storms,is crucial for both flood control and prevention.Utilizing data-driven models that harness deep learning(DL)techniques has emerged as an attractive and effective approach to water level prediction.This paper proposed an innovative data-driven methodology using DL network architectures of Gated Recurrent Unit(GRU),Long Short-Term Memory(LSTM),and Bidirectional Long-Short Term Memory(Bi-LSTM)to predict the water level at the Le Thuy station in the Kien Giang River.These models were implemented and validated based on hourly rainfall and water level observations at meteo-hydrological stations.Three combinations of input variables with different time leads and time lags were established to evaluate the forecast capability of three proposed models by using five metrics,that is,R2,MAE,RMSE,Max Error Value,and Max Error Time.The results revealed that the LSTM model outperformed the Bi-LSTM and GRU models,when water level and rainfall observations for one-time lag at three stations were used to predict the water level at the Le Thuy station with 1-h time lead,with the five metrics registering at 0.999;3.6 cm;2.6 cm;12.9 cm;and−1 h,respectively.
基金The National Natural Science Foundation of China under contract Nos T2261149752 and 42476172the Open Funding of the Technology Innovation Center for South China Sea Remote Sensing,Surveying and Mapping Collaborative Application,Ministry of Natural Resources,P.R.China under contract No.RSSMCA-2024-B001。
文摘High-accuracy Sea level prediction is important for understanding marine environments and climate change.In this work,a deep convolutional neural network(CNN)combined with attention mechanism(ADNN)is established for sea level anomaly(SLA)prediction from historical satellite observations.Multi-year(1998-2020)radar altimetry observed SLA pattern samples in the South China Sea are used for model training and testing.Compared with existing deep learning models such as CNN and convolutional long short-term memory(ConvLSTM)network,ADNN demonstrates the highest accuracies of 94.0%,91.1%,88.4%and 86.2%for 1-d,3-d,5-d and 7-d SLA field predictions,with regional average root mean square errors(RMSE)of 0.27 cm,0.51 cm,0.80 cm and 1.09 cm,respectively.The integration of CNN and attention mechanism significantly improves the model performance,especially in estimating short-term sea level changes,with a 74.7%reduction in the RMSE for 1-d predictions compared to the baseline CNN model.Comparative experiments also show that the ADNN model performs well when the input data contains a certain degree of noise.Moreover,a multivariate ADNN(M-ADNN)model is designed to investigate the impacts of environmental variables such as sea surface temperature(SST)and wind on SLA prediction.The model yields a slightly higher accuracy but the results are quite similar to those of the ADNN model.The findings suggest that,although SST or wind can affect sea level changes,the ADNN model demonstrates the ability to identify and learn sufficient information about sea level changes solely from satellite altimetry measurements of SLA,especially for relatively long-term(≥5 d)predictions.This eliminates the need for additional input parameter data,thereby improving the SLA prediction efficiency.
基金The National Natural Science Foundation of China under contract No.51379002the Fundamental Research Funds for the Central Universities of China under contract Nos 3132016322 and 3132016314the Applied Basic Research Project Fund of the Chinese Ministry of Transport of China under contract No.2014329225010
文摘An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variation of the tidal level is a time-varying process. The time-varying factors including interference from the external environment that cause the change of tides are fairly complicated. Furthermore, tidal variations are affected not only by periodic movement of celestial bodies but also by time-varying interference from the external environment. Consequently, for the efficient and precise tidal level prediction, a neuro-fuzzy hybrid technology based on the combination of harmonic analysis and adaptive network-based fuzzy inference system（ANFIS）model is utilized to construct a precise tidal level prediction system, which takes both advantages of the harmonic analysis method and the ANFIS network. The proposed prediction model is composed of two modules： the astronomical tide module caused by celestial bodies’ movement and the non-astronomical tide module caused by various meteorological and other environmental factors. To generate a fuzzy inference system（FIS） structure,three approaches which include grid partition（GP）, fuzzy c-means（FCM） and sub-clustering（SC） are used in the ANFIS network constructing process. Furthermore, to obtain the optimal ANFIS based prediction model, large numbers of simulation experiments are implemented for each FIS generating approach. In this tidal prediction study, the optimal ANFIS model is used to predict the non-astronomical tide module, while the conventional harmonic analysis model is used to predict the astronomical tide module. The final prediction result is performed by combining the estimation outputs of the harmonious analysis model and the optimal ANFIS model. To demonstrate the applicability and capability of the proposed novel prediction model, measured tidal level samples of Fort Pulaski tidal station are selected as the testing database. Simulation and experimental results confirm that the proposed prediction approach can achieve precise predictions for the tidal level with high accuracy, satisfactory convergence and stability.
基金the University of Tabriz through a Grant scheme No.808.
文摘An explicit model management framework is introduced for predictive Groundwater Levels(GWL),particularly suitable to Observation Wells(OWs)with sparse and possibly heterogeneous data.The framework implements Multiple Models(MM)under the architecture of organising them at levels,as follows:(i)Level 0:treat heterogeneity in the data,e.g.Self-Organised Mapping(SOM)to classify the OWs;and decide on model structure,e.g.formulate a grey box model to predict GWLs.(ii)Level 1:construct MMs,e.g.two Fuzzy Logic(FL)and one Neurofuzzy(NF)models.(iii)Level 2:formulate strategies to combine the MM at Level 1,for which the paper uses Artificial Neural Networks(Strategy 1)and simple averaging(Strategy 2).Whilst the above model management strategy is novel,a critical view is presented,according to which modelling practices are:Inclusive Multiple Modelling(IMM)practices contrasted with existing practices,branded by the paper as Exclusionary Multiple Modelling(EMM).Scientific thinking over IMMs is captured as a framework with four dimensions:Model Reuse(MR),Hierarchical Recursion(HR),Elastic Learning Environment(ELE)and Goal Orientation(GO)and these together make the acronym of RHEO.Therefore,IMM-RHEO is piloted in the aquifer of Tabriz Plain with sparse and possibly heterogeneous data.The results provide some evidence that(i)IMM at two levels improves on the accuracy of individual models;and(ii)model combinations in IMM practices bring‘model-learning’into fashion for learning with the goal to explain baseline conditions and impacts of subsequent management changes.
基金Funding of Jiangsu Innovation Program for Graduate Education (CXZZ11_0193)NUAA Research Funding (NJ2010009)
文摘An improved method using kernel density estimation （KDE） and confidence level is presented for model validation with small samples. Decision making is a challenging problem because of input uncertainty and only small samples can be used due to the high costs of experimental measurements. However, model validation provides more confidence for decision makers when improving prediction accuracy at the same time. The confidence level method is introduced and the optimum sample variance is determined using a new method in kernel density estimation to increase the credibility of model validation. As a numerical example, the static frame model validation challenge problem presented by Sandia National Laboratories has been chosen. The optimum bandwidth is selected in kernel density estimation in order to build the probability model based on the calibration data. The model assessment is achieved using validation and accreditation experimental data respectively based on the probability model. Finally, the target structure prediction is performed using validated model, which are consistent with the results obtained by other researchers. The results demonstrate that the method using the improved confidence level and kernel density estimation is an effective approach to solve the model validation problem with small samples.
文摘Nowadays, the deep learning methods are widely applied to analyze and predict the trend of various disaster events and offer the alternatives to make the appropriate decisions. These support the water resource management and the short-term planning. In this paper, the water levels of the Pattani River in the Southern of Thailand have been predicted every hour of 7 days forecast. Time Series Transformer and Linear Regression were applied in this work. The results of both were the water levels forecast that had the high accuracy. Moreover, the water levels forecasting dashboard was developed for using to monitor the water levels at the Pattani River as well.
基金supported by JSPS KAKENHI Grant Number JP21K14064 and JP23K13239.
文摘Maintaining high groundwater level(GWL)is important for preventing fires in peatlands.This study proposes GWL prediction using machine learning methods for forest plantations in Indonesian tropical peatlands.Deep neural networks(DNN)have been used for prediction;however,they have not been applied to groundwater prediction in Indonesian peatlands.Tropical peatland is characterized by high permeability and forest plantations are surrounded by several canals.By predicting daily differences in GWL,the GWL can be predicted with high accuracy.DNNs,random forests,support vector regression,and XGBoost were compared,all of which indicated similar errors.The SHAP value revealed that the precipitation falling on the hill rapidly seeps into the soil and flows into the canals,which agrees with the fact that the soil has high permeability.These findings can potentially be used to alleviate and manage future fires in peatlands.
基金Supported by National Natural Science Foundation of China(No.51777193).
文摘The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multienergy complementary ways.Focusing on the regional integrated energy system composed of electrical microgrid and natural gas network,a fault risk warning method based on the improved RelieF-softmax method is proposed in this paper.The raw data-set was first clustered by the K-maxmin method to improve the preference of the random sampling process in the RelieF algorithm,and thereby achieved a hierarchical and non-repeated sampling.Then,the improved RelieF algorithm is used to identify the feature vectors,calculate the feature weights,and select the preferred feature subset according to the initially set threshold.In addition,a correlation coefficient method is applied to reduce the feature subset,and further eliminate the redundant feature vectors to obtain the optimal feature subset.Finally,the softmax classifier is used to obtain the early warnings of the integrated energy system.Case studies are conducted on an integrated energy system in the south of China to demonstrate the accuracy of fault risk warning method proposed in this paper.
文摘The prediction of groundwater level is important for the use and management of groundwater resources. In this paper, the artificial neural networks (ANN) were used to predict groundwater level in the Dawu Aquifer of Zibo in Eastern China. The first step was an auto-correlation analysis of the groundwater level which showed that the monthly groundwater level was time dependent. An auto-regression type ANN (ARANN) model and a regression-auto-regression type ANN (RARANN) model using back-propagation algorithm were then used to predict the groundwater level. Monthly data from June 1988 to May 1998 was used for the network training and testing. The results show that the RARANN model is more reliable than the ARANN model, especially in the testing period, which indicates that the RARANN model can describe the relationship between the groundwater fluctuation and main factors that currently influence the groundwater level. The results suggest that the model is suitable for predicting groundwater level fluctuations in this area for similar conditions in the future.
基金supported by the National Natural Science Foundation of China(62506031,62332017,U22A2022)National Science and Technology Major Project of the Ministry of Science and Technology of China(2024ZD0608100).
文摘This study explores the potential of the advanced selective state spaces model(SSSM)in modeling complicated process industries system and proposes the process industry state identification model(PISIM)for controlled prediction of flotation cell pulp level.As a neural system identification model,the PISIM inherits two advantages of the SSSM to address the challenges in identifying flotation systems,including modeling the impact of frequent upstream fluctuations on system states,complex nonlinear physicochemical processes,and long-term dependencies.The first advantage is the ability to capture long-range dependencies,thereby boosting its long-term predictive accuracy.The second lies in the model structure adhering to scaling laws,enabling ongoing enhancements in performance as datasets expand.PISIM is evaluated using a real industrial dataset from a flotation plant at a copper mine in Zambia,with the results demonstrating its theoretical advantages.In a 4.5-hour pulp level prediction task,PISIM outperforms the baseline model by more than 31.34%.Furthermore,a flotation process control simulation experimental system based on PISIM is developed and deployed in a flotation plant in Zambia,assisting engineers in evaluating and optimizing setpoint strategies,ensuring stable production and improving production efficiency.
文摘The prosperity of deep learning has revolutionized many machine learning tasks(such as image recognition,natural language processing,etc.).With the widespread use of autonomous sensor networks,the Internet of Things,and crowd sourcing to monitor real-world processes,the volume,diversity,and veracity of spatial-temporal data are expanding rapidly.However,traditional methods have their limitation in coping with spatial-temporal dependencies,which either incorporate too much data from weakly connected locations or ignore the relationships between those interrelated but geographically separated regions.In this paper,a novel deep learning model(termed RF-GWN)is proposed by combining Random Forest(RF)and Graph WaveNet(GWN).In RF-GWN,a new adaptive weight matrix is formulated by combining Variable Importance Measure(VIM)of RF with the long time series feature extraction ability of GWN in order to capture potential spatial dependencies and extract long-term dependencies from the input data.Furthermore,two experiments are conducted on two real-world datasets with the purpose of predicting traffic flow and groundwater level.Baseline models are implemented by Diffusion Convolutional Recurrent Neural Network(DCRNN),Spatial-Temporal GCN(ST-GCN),and GWN to verify the effectiveness of the RF-GWN.The Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and Mean Absolute Percentage Error(MAPE)are selected as performance criteria.The results show that the proposed model can better capture the spatial-temporal relationships,the prediction performance on the METR-LA dataset is slightly improved,and the index of the prediction task on the PEMS-BAY dataset is significantly improved.These improvements are extended to the groundwater dataset,which can effectively improve the prediction accuracy.Thus,the applicability and effectiveness of the proposed model RF-GWN in both traffic flow and groundwater level prediction are demonstrated.
