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Experiments on image data augmentation techniques for geological rock type classification with convolutional neural networks 被引量:1
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作者 Afshin Tatar Manouchehr Haghighi Abbas Zeinijahromi 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期106-125,共20页
The integration of image analysis through deep learning(DL)into rock classification represents a significant leap forward in geological research.While traditional methods remain invaluable for their expertise and hist... The integration of image analysis through deep learning(DL)into rock classification represents a significant leap forward in geological research.While traditional methods remain invaluable for their expertise and historical context,DL offers a powerful complement by enhancing the speed,objectivity,and precision of the classification process.This research explores the significance of image data augmentation techniques in optimizing the performance of convolutional neural networks(CNNs)for geological image analysis,particularly in the classification of igneous,metamorphic,and sedimentary rock types from rock thin section(RTS)images.This study primarily focuses on classic image augmentation techniques and evaluates their impact on model accuracy and precision.Results demonstrate that augmentation techniques like Equalize significantly enhance the model's classification capabilities,achieving an F1-Score of 0.9869 for igneous rocks,0.9884 for metamorphic rocks,and 0.9929 for sedimentary rocks,representing improvements compared to the baseline original results.Moreover,the weighted average F1-Score across all classes and techniques is 0.9886,indicating an enhancement.Conversely,methods like Distort lead to decreased accuracy and F1-Score,with an F1-Score of 0.949 for igneous rocks,0.954 for metamorphic rocks,and 0.9416 for sedimentary rocks,exacerbating the performance compared to the baseline.The study underscores the practicality of image data augmentation in geological image classification and advocates for the adoption of DL methods in this domain for automation and improved results.The findings of this study can benefit various fields,including remote sensing,mineral exploration,and environmental monitoring,by enhancing the accuracy of geological image analysis both for scientific research and industrial applications. 展开更多
关键词 Deep learning(DL) Image analysis Image data augmentation convolutional neural networks(cnns) Geological image analysis Rock classification Rock thin section(RTS)images
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A hybrid data-driven approach for rainfall-induced landslide susceptibility mapping:Physically-based probabilistic model with convolutional neural network
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作者 Hong-Zhi Cui Bin Tong +2 位作者 Tao Wang Jie Dou Jian Ji 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期4933-4951,共19页
Landslide susceptibility mapping(LSM)plays a crucial role in assessing geological risks.The current LSM techniques face a significant challenge in achieving accurate results due to uncertainties associated with region... Landslide susceptibility mapping(LSM)plays a crucial role in assessing geological risks.The current LSM techniques face a significant challenge in achieving accurate results due to uncertainties associated with regional-scale geotechnical parameters.To explore rainfall-induced LSM,this study proposes a hybrid model that combines the physically-based probabilistic model(PPM)with convolutional neural network(CNN).The PPM is capable of effectively capturing the spatial distribution of landslides by incorporating the probability of failure(POF)considering the slope stability mechanism under rainfall conditions.This significantly characterizes the variation of POF caused by parameter uncertainties.CNN was used as a binary classifier to capture the spatial and channel correlation between landslide conditioning factors and the probability of landslide occurrence.OpenCV image enhancement technique was utilized to extract non-landslide points based on the POF of landslides.The proposed model comprehensively considers physical mechanics when selecting non-landslide samples,effectively filtering out samples that do not adhere to physical principles and reduce the risk of overfitting.The results indicate that the proposed PPM-CNN hybrid model presents a higher prediction accuracy,with an area under the curve(AUC)value of 0.85 based on the landslide case of the Niangniangba area of Gansu Province,China compared with the individual CNN model(AUC=0.61)and the PPM(AUC=0.74).This model can also consider the statistical correlation and non-normal probability distributions of model parameters.These results offer practical guidance for future research on rainfall-induced LSM at the regional scale. 展开更多
关键词 Rainfall landslides Landslide susceptibility mapping Hybrid model Physically-based model Convolution neural network(cnn) Probability of failure(POF)
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Optimization of convolutional neural networks for predicting water pollutants using spectral data in the middle and lower reaches of the Yangtze River Basin,China
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作者 ZHANG Guohao LI Song +3 位作者 WANG Cailing WANG Hongwei YU Tao DAI Xiaoxu 《Journal of Mountain Science》 2025年第8期2851-2869,共19页
Developing an accurate and efficient comprehensive water quality prediction model and its assessment method is crucial for the prevention and control of water pollution.Deep learning(DL),as one of the most promising t... Developing an accurate and efficient comprehensive water quality prediction model and its assessment method is crucial for the prevention and control of water pollution.Deep learning(DL),as one of the most promising technologies today,plays a crucial role in the effective assessment of water body health,which is essential for water resource management.This study models using both the original dataset and a dataset augmented with Generative Adversarial Networks(GAN).It integrates optimization algorithms(OA)with Convolutional Neural Networks(CNN)to propose a comprehensive water quality model evaluation method aiming at identifying the optimal models for different pollutants.Specifically,after preprocessing the spectral dataset,data augmentation was conducted to obtain two datasets.Then,six new models were developed on these datasets using particle swarm optimization(PSO),genetic algorithm(GA),and simulated annealing(SA)combined with CNN to simulate and forecast the concentrations of three water pollutants:Chemical Oxygen Demand(COD),Total Nitrogen(TN),and Total Phosphorus(TP).Finally,seven model evaluation methods,including uncertainty analysis,were used to evaluate the constructed models and select the optimal models for the three pollutants.The evaluation results indicate that the GPSCNN model performed best in predicting COD and TP concentrations,while the GGACNN model excelled in TN concentration prediction.Compared to existing technologies,the proposed models and evaluation methods provide a more comprehensive and rapid approach to water body prediction and assessment,offering new insights and methods for water pollution prevention and control. 展开更多
关键词 Water pollutants convolutional neural networks Data augmentation Optimization algorithms model evaluation methods Deep Learning
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Big Model Strategy for Bridge Structural Health Monitoring Based on Data-Driven, Adaptive Method and Convolutional Neural Network (CNN) Group 被引量:1
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作者 Yadong Xu Weixing Hong +3 位作者 Mohammad Noori Wael A.Altabey Ahmed Silik Nabeel S.D.Farhan 《Structural Durability & Health Monitoring》 EI 2024年第6期763-783,共21页
This study introduces an innovative“Big Model”strategy to enhance Bridge Structural Health Monitoring(SHM)using a Convolutional Neural Network(CNN),time-frequency analysis,and fine element analysis.Leveraging ensemb... This study introduces an innovative“Big Model”strategy to enhance Bridge Structural Health Monitoring(SHM)using a Convolutional Neural Network(CNN),time-frequency analysis,and fine element analysis.Leveraging ensemble methods,collaborative learning,and distributed computing,the approach effectively manages the complexity and scale of large-scale bridge data.The CNN employs transfer learning,fine-tuning,and continuous monitoring to optimize models for adaptive and accurate structural health assessments,focusing on extracting meaningful features through time-frequency analysis.By integrating Finite Element Analysis,time-frequency analysis,and CNNs,the strategy provides a comprehensive understanding of bridge health.Utilizing diverse sensor data,sophisticated feature extraction,and advanced CNN architecture,the model is optimized through rigorous preprocessing and hyperparameter tuning.This approach significantly enhances the ability to make accurate predictions,monitor structural health,and support proactive maintenance practices,thereby ensuring the safety and longevity of critical infrastructure. 展开更多
关键词 Structural Health Monitoring(SHM) BRIDGES big model convolutional neural Network(cnn) Finite Element Method(FEM)
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Prediction of constrained modulus for granular soil using 3D discrete element method and convolutional neural networks 被引量:1
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作者 Tongwei Zhang Shuang Li +1 位作者 Huanzhi Yang Fanyu Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4769-4781,共13页
To efficiently predict the mechanical parameters of granular soil based on its random micro-structure,this study proposed a novel approach combining numerical simulation and machine learning algorithms.Initially,3500 ... To efficiently predict the mechanical parameters of granular soil based on its random micro-structure,this study proposed a novel approach combining numerical simulation and machine learning algorithms.Initially,3500 simulations of one-dimensional compression tests on coarse-grained sand using the three-dimensional(3D)discrete element method(DEM)were conducted to construct a database.In this process,the positions of the particles were randomly altered,and the particle assemblages changed.Interestingly,besides confirming the influence of particle size distribution parameters,the stress-strain curves differed despite an identical gradation size statistic when the particle position varied.Subsequently,the obtained data were partitioned into training,validation,and testing datasets at a 7:2:1 ratio.To convert the DEM model into a multi-dimensional matrix that computers can recognize,the 3D DEM models were first sliced to extract multi-layer two-dimensional(2D)cross-sectional data.Redundant information was then eliminated via gray processing,and the data were stacked to form a new 3D matrix representing the granular soil’s fabric.Subsequently,utilizing the Python language and Pytorch framework,a 3D convolutional neural networks(CNNs)model was developed to establish the relationship between the constrained modulus obtained from DEM simulations and the soil’s fabric.The mean squared error(MSE)function was utilized to assess the loss value during the training process.When the learning rate(LR)fell within the range of 10-5e10-1,and the batch sizes(BSs)were 4,8,16,32,and 64,the loss value stabilized after 100 training epochs in the training and validation dataset.For BS?32 and LR?10-3,the loss reached a minimum.In the testing set,a comparative evaluation of the predicted constrained modulus from the 3D CNNs versus the simulated modulus obtained via DEM reveals a minimum mean absolute percentage error(MAPE)of 4.43%under the optimized condition,demonstrating the accuracy of this approach.Thus,by combining DEM and CNNs,the variation of soil’s mechanical characteristics related to its random fabric would be efficiently evaluated by directly tracking the particle assemblages. 展开更多
关键词 Soil structure Constrained modulus Discrete element model(DEM) convolutional neural networks(cnns) Evaluation of error
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CNN-based multi-output regression model to estimate infrastructural surface crack dimensions adopting a generalised patch size and FWHM-based width quantification
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作者 Sudipta Debroy Arjun Sil 《Digital Twins and Applications》 2025年第1期75-102,共28页
To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks o... To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks obtained from a public dataset are cropped into patches of 256 square pixels that are classified with a pre-trained deep convolution neural network,the true positives are segmented,and crack properties are extracted using two different methods.The first method is primarily based on active contour models and level-set segmentation and the second method consists of the domain adaptation of a mathematical morphology-based method known as FIL-FINDER.A statistical test has been performed for the comparison of the stated methods and a database prepared with the more suitable method.An advanced convolution neural network-based multi-output regression model has been proposed which was trained with the prepared database and validated with the held-out dataset for the prediction of crack-length,crack-width,and width-uncertainty directly from input image patches.The pro-posed model has been tested on crack patches collected from different locations.Huber loss has been used to ensure the robustness of the proposed model selected from a set of 288 different variations of it.Additionally,an ablation study has been conducted on the top 3 models that demonstrated the influence of each network component on the pre-diction results.Finally,the best performing model HHc-X among the top 3 has been proposed that predicted crack properties which are in close agreement to the ground truths in the test data. 展开更多
关键词 ablation cnn convolution neural network CRACK crack patch estimation FWHM length multi-output regression segmentation uncertainty WIDTH
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Predicting outcomes using neural networks in the intensive care unit
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作者 Gumpeny R Sridhar Venkat Yarabati Lakshmi Gumpeny 《World Journal of Clinical Cases》 2025年第11期1-11,共11页
Patients in intensive care units(ICUs)require rapid critical decision making.Modern ICUs are data rich,where information streams from diverse sources.Machine learning(ML)and neural networks(NN)can leverage the rich da... Patients in intensive care units(ICUs)require rapid critical decision making.Modern ICUs are data rich,where information streams from diverse sources.Machine learning(ML)and neural networks(NN)can leverage the rich data for prognostication and clinical care.They can handle complex nonlinear relation-ships in medical data and have advantages over traditional predictive methods.A number of models are used:(1)Feedforward networks;and(2)Recurrent NN and convolutional NN to predict key outcomes such as mortality,length of stay in the ICU and the likelihood of complications.Current NN models exist in silos;their integration into clinical workflow requires greater transparency on data that are analyzed.Most models that are accurate enough for use in clinical care operate as‘black-boxes’in which the logic behind their decision making is opaque.Advan-ces have occurred to see through the opacity and peer into the processing of the black-box.In the near future ML is positioned to help in clinical decision making far beyond what is currently possible.Transparency is the first step toward vali-dation which is followed by clinical trust and adoption.In summary,NNs have the transformative ability to enhance predictive accuracy and improve patient management in ICUs.The concept should soon be turning into reality. 展开更多
关键词 Large language models HALLUCINATIONS Supervised learning Unsupervised learning Convoluted neural networks BLACK-BOX WORKFLOW
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Spatial-temporal simulation and prediction of root zone soil moisture based on Hydrus-1D and CNN-LSTM-attention models in Yutian Oasis,southern Xinjiang,China
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作者 Xiaobo LÜ Ilyas NURMEMET +4 位作者 Sentian XIAO Jing ZHAO Xinru YU Yilizhati AILI Shiqin LI 《Pedosphere》 2025年第5期846-857,共12页
Root zone soil moisture(RZSM)plays a critical role in land-atmosphere hydrological cycles and serves as the primary water source for vegetation growth.However,the correlations between RZSM and its associated variables... Root zone soil moisture(RZSM)plays a critical role in land-atmosphere hydrological cycles and serves as the primary water source for vegetation growth.However,the correlations between RZSM and its associated variables,including surface soil moisture(SSM),often exhibit nonlinearities that are challenging to identify and quantify using conventional statistical techniques.Therefore,this study presents a hybrid convolutional neural network(CNN)-long short-term memory neural network(LSTM)-attention(CLA)model for predicting RZSM.Owing to the scarcity of soil moisture(SM)observation data,the physical model Hydrus-1D was employed to simulate a comprehensive dataset of spatial-temporal SM.Meteorological data and moderate resolution imaging spectroradiometer vegetation characterization parameters were used as predictor variables for the training and validation of the CLA model.The results of the CLA model for SM prediction in the root zone were significantly enhanced compared with those of the traditional LSTM and CNN-LSTM models.This was particularly notable at the depth of 80–100 cm,where the fitness(R^(2))reached nearly 0.9298.Moreover,the root mean square error of the CLA model was reduced by 49%and 57%compared with those of the LSTM and CNN-LSTM models,respectively.This study demonstrates that the integration of physical modeling and deep learning methods provides a more comprehensive and accurate understanding of spatial-temporal SM variations in the root zone. 展开更多
关键词 arid region convolutional neural network deep learning method hybrid prediction model leaf area index long short-term memory neural network normalized difference vegetation index physical model surface soil moisture
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Enhancing the genomic prediction accuracy of swine agricultural economic traits using an expanded one-hot encoding in CNN models
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作者 Zishuai Wang Wangchang Li Zhonglin Tang 《Journal of Integrative Agriculture》 2025年第9期3574-3582,共9页
Deep learning(DL)methods like multilayer perceptrons(MLPs)and convolutional neural networks(CNNs)have been applied to predict the complex traits in animal and plant breeding.However,improving the genomic prediction ac... Deep learning(DL)methods like multilayer perceptrons(MLPs)and convolutional neural networks(CNNs)have been applied to predict the complex traits in animal and plant breeding.However,improving the genomic prediction accuracy still presents signifcant challenges.In this study,we applied CNNs to predict swine traits using previously published data.Specifcally,we extensively evaluated the CNN model's performance by employing various sets of single nucleotide polymorphisms(SNPs)and concluded that the CNN model achieved optimal performance when utilizing SNP sets comprising 1,000 SNPs.Furthermore,we adopted a novel approach using the one-hot encoding method that transforms the 16 different genotypes into sets of eight binary variables.This innovative encoding method signifcantly enhanced the CNN's prediction accuracy for swine traits,outperforming the traditional one-hot encoding techniques.Our fndings suggest that the expanded one-hot encoding method can improve the accuracy of DL methods in the genomic prediction of swine agricultural economic traits.This discovery has significant implications for swine breeding programs,where genomic prediction is pivotal in improving breeding strategies.Furthermore,future research endeavors can explore additional enhancements to DL methods by incorporating advanced data pre-processing techniques. 展开更多
关键词 SWINE agricultural economic traits genomic prediction deep learning one-hot encoding convolutional neural networks(cnns)
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Noninvasive Hemoglobin Estimation with Adaptive Lightweight Convolutional Neural Network Using Wearable PPG
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作者 Florentin Smarandache Saleh I.Alzahrani +2 位作者 Sulaiman Al Amro Ijaz Ahmad Mubashir Ali 《Computer Modeling in Engineering & Sciences》 2025年第9期3715-3735,共21页
Hemoglobin is a vital protein in red blood cells responsible for transporting oxygen throughout the body.Its accurate measurement is crucial for diagnosing and managing conditions such as anemia and diabetes,where abn... Hemoglobin is a vital protein in red blood cells responsible for transporting oxygen throughout the body.Its accurate measurement is crucial for diagnosing and managing conditions such as anemia and diabetes,where abnormal hemoglobin levels can indicate significant health issues.Traditional methods for hemoglobin measurement are invasive,causing pain,risk of infection,and are less convenient for frequent monitoring.PPG is a transformative technology in wearable healthcare for noninvasive monitoring and widely explored for blood pressure,sleep,blood glucose,and stress analysis.In this work,we propose a hemoglobin estimation method using an adaptive lightweight convolutional neural network(HMALCNN)from PPG.The HMALCNN is designed to capture both fine-grained local waveform characteristics and global contextual patterns,ensuring robust performance across acquisition settings.We validated our approach on two multi-regional datasets containing 152 and 68 subjects,respectively,employing a subjectindependent 5-fold cross-validation strategy.The proposed method achieved root mean square errors(RMSE)of 0.90 and 1.20 g/dL for the two datasets,with strong Pearson correlations of 0.82 and 0.72.We conducted extensive posthoc analyses to assess clinical utility and interpretability.A±1 g/dL clinical error tolerance evaluation revealed that 91.3%and 86.7%of predictions for the two datasets fell within the acceptable clinical range.Hemoglobin range-wise analysis demonstrated consistently high accuracy in the normal and low hemoglobin categories.Statistical significance testing using the Wilcoxon signed-rank test confirmed the stability of performance across validation folds(p>0.05 for both RMSE and correlation).Furthermore,model interpretability was enhanced using Gradient-weighted Class Activation Mapping(Grad-CAM),supporting the model’s clinical trustworthiness.The proposed HMALCNN offers a computationally efficient,clinically interpretable,and generalizable framework for noninvasive hemoglobin monitoring,with strong potential for integration into wearable healthcare systems as a practical alternative to invasive measurement techniques. 展开更多
关键词 Hemoglobin estimation photoplethysmography(PPG) convolutional neural network(cnn) noninvasive method wearable healthcare
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Attention⁃Based Multi⁃scale CNN and LSTM Model for Remaining Useful Life Estimation
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作者 DUAN Jiajun LU Zhong DU Zhiqiang 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第S1期64-77,共14页
Current aero-engine life prediction areas typically focus on single-scale degradation features,and the existing methods are not comprehensive enough to capture the relationship within time series data.To address this ... Current aero-engine life prediction areas typically focus on single-scale degradation features,and the existing methods are not comprehensive enough to capture the relationship within time series data.To address this problem,we propose a novel remaining useful life(RUL)estimation method based on the attention mechanism.Our approach designs a two-layer multi-scale feature extraction module that integrates degradation features at different scales.These features are then processed in parallel by a self-attention module and a three-layer long short-term memory(LSTM)network,which together capture long-term dependencies and adaptively weigh important feature.The integration of degradation patterns from both components into the attention module enhances the model’s ability to capture long-term dependencies.Visualizing the attention module’s weight matrices further improves model interpretability.Experimental results on the C-MAPSS dataset demonstrate that our approach outperforms the existing state-of-the-art methods. 展开更多
关键词 attention mechanism convolutional neural network(cnn) long short-term memory(LSTM) multi-scale feature extraction
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Enhanced Fault Detection and Diagnosis in Photovoltaic Arrays Using a Hybrid NCA-CNN Model
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作者 Umit Cigdem Turhal Yasemin Onal Kutalmis Turhal 《Computer Modeling in Engineering & Sciences》 2025年第5期2307-2332,共26页
The reliability and efficiency of photovoltaic(PV)systems are essential for sustainable energy produc-tion,requiring accurate fault detection to minimize energy losses.This study proposes a hybrid model integrating Ne... The reliability and efficiency of photovoltaic(PV)systems are essential for sustainable energy produc-tion,requiring accurate fault detection to minimize energy losses.This study proposes a hybrid model integrating Neighborhood Components Analysis(NCA)with a Convolutional Neural Network(CNN)to improve fault detection and diagnosis.Unlike Principal Component Analysis(PCA),which may compromise class relationships during feature extraction,NCA preserves these relationships,enhancing classification performance.The hybrid model combines NCA with CNN,a fundamental deep learning architecture,to enhance fault detection and diagnosis capabilities.The performance of the proposed NCA-CNN model was evaluated against other models.The experimental evaluation demonstrates that the NCA-CNN model outperforms existing methods,achieving 100%fault detection accuracy and 99%fault diagnosis accuracy.These findings underscore the model’s potential in improving PV system reliability and efficiency. 展开更多
关键词 Artificial intelligence photovoltaic energy systems machine learning photovoltaic fault detection and diagnosis convolutional neural networks(cnn) neighbourhood component analysis(NCA)
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Deep Convolution Neural Networks for Image-Based Android Malware Classification
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作者 Amel Ksibi Mohammed Zakariah +1 位作者 Latifah Almuqren Ala Saleh Alluhaidan 《Computers, Materials & Continua》 2025年第3期4093-4116,共24页
The analysis of Android malware shows that this threat is constantly increasing and is a real threat to mobile devices since traditional approaches,such as signature-based detection,are no longer effective due to the ... The analysis of Android malware shows that this threat is constantly increasing and is a real threat to mobile devices since traditional approaches,such as signature-based detection,are no longer effective due to the continuously advancing level of sophistication.To resolve this problem,efficient and flexible malware detection tools are needed.This work examines the possibility of employing deep CNNs to detect Android malware by transforming network traffic into image data representations.Moreover,the dataset used in this study is the CIC-AndMal2017,which contains 20,000 instances of network traffic across five distinct malware categories:a.Trojan,b.Adware,c.Ransomware,d.Spyware,e.Worm.These network traffic features are then converted to image formats for deep learning,which is applied in a CNN framework,including the VGG16 pre-trained model.In addition,our approach yielded high performance,yielding an accuracy of 0.92,accuracy of 99.1%,precision of 98.2%,recall of 99.5%,and F1 score of 98.7%.Subsequent improvements to the classification model through changes within the VGG19 framework improved the classification rate to 99.25%.Through the results obtained,it is clear that CNNs are a very effective way to classify Android malware,providing greater accuracy than conventional techniques.The success of this approach also shows the applicability of deep learning in mobile security along with the direction for the future advancement of the real-time detection system and other deeper learning techniques to counter the increasing number of threats emerging in the future. 展开更多
关键词 Android malware detection deep convolutional neural network(Dcnn) image processing CIC-AndMal2017 dataset exploratory data analysis VGG16 model
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Downscaling Seasonal Precipitation Forecasts over East Africa with Deep Convolutional Neural Networks
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作者 Temesgen Gebremariam ASFAW Jing-Jia LUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期449-464,共16页
This study assesses the suitability of convolutional neural networks(CNNs) for downscaling precipitation over East Africa in the context of seasonal forecasting. To achieve this, we design a set of experiments that co... This study assesses the suitability of convolutional neural networks(CNNs) for downscaling precipitation over East Africa in the context of seasonal forecasting. To achieve this, we design a set of experiments that compare different CNN configurations and deployed the best-performing architecture to downscale one-month lead seasonal forecasts of June–July–August–September(JJAS) precipitation from the Nanjing University of Information Science and Technology Climate Forecast System version 1.0(NUIST-CFS1.0) for 1982–2020. We also perform hyper-parameter optimization and introduce predictors over a larger area to include information about the main large-scale circulations that drive precipitation over the East Africa region, which improves the downscaling results. Finally, we validate the raw model and downscaled forecasts in terms of both deterministic and probabilistic verification metrics, as well as their ability to reproduce the observed precipitation extreme and spell indicator indices. The results show that the CNN-based downscaling consistently improves the raw model forecasts, with lower bias and more accurate representations of the observed mean and extreme precipitation spatial patterns. Besides, CNN-based downscaling yields a much more accurate forecast of extreme and spell indicators and reduces the significant relative biases exhibited by the raw model predictions. Moreover, our results show that CNN-based downscaling yields better skill scores than the raw model forecasts over most portions of East Africa. The results demonstrate the potential usefulness of CNN in downscaling seasonal precipitation predictions over East Africa,particularly in providing improved forecast products which are essential for end users. 展开更多
关键词 East Africa seasonal precipitation forecasting DOWNSCALING deep learning convolutional neural networks(cnns)
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Review of Artificial Intelligence for Oil and Gas Exploration: Convolutional Neural Network Approaches and the U-Net 3D Model
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作者 Weiyan Liu 《Open Journal of Geology》 CAS 2024年第4期578-593,共16页
Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Ou... Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Our review traces the evolution of CNN, emphasizing the adaptation and capabilities of the U-Net 3D model in automating seismic fault delineation with unprecedented accuracy. We find: 1) The transition from basic neural networks to sophisticated CNN has enabled remarkable advancements in image recognition, which are directly applicable to analyzing seismic data. The U-Net 3D model, with its innovative architecture, exemplifies this progress by providing a method for detailed and accurate fault detection with reduced manual interpretation bias. 2) The U-Net 3D model has demonstrated its superiority over traditional fault identification methods in several key areas: it has enhanced interpretation accuracy, increased operational efficiency, and reduced the subjectivity of manual methods. 3) Despite these achievements, challenges such as the need for effective data preprocessing, acquisition of high-quality annotated datasets, and achieving model generalization across different geological conditions remain. Future research should therefore focus on developing more complex network architectures and innovative training strategies to refine fault identification performance further. Our findings confirm the transformative potential of deep learning, particularly CNN like the U-Net 3D model, in geosciences, advocating for its broader integration to revolutionize geological exploration and seismic analysis. 展开更多
关键词 Deep Learning convolutional neural networks (cnn) Seismic Fault Identification U-Net 3D model Geological Exploration
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Application of convolutional neural networks to large-scale naphtha pyrolysis kinetic modeling 被引量:8
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作者 Feng Hua Zhou Fang Tong Qiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第12期2562-2572,共11页
System design and optimization problems require large-scale chemical kinetic models. Pure kinetic models of naphtha pyrolysis need to solve a complete set of stiff ODEs and is therefore too computational expensive. On... System design and optimization problems require large-scale chemical kinetic models. Pure kinetic models of naphtha pyrolysis need to solve a complete set of stiff ODEs and is therefore too computational expensive. On the other hand, artificial neural networks that completely neglect the topology of the reaction networks often have poor generalization. In this paper, a framework is proposed for learning local representations from largescale chemical reaction networks. At first, the features of naphtha pyrolysis reactions are extracted by applying complex network characterization methods. The selected features are then used as inputs in convolutional architectures. Different CNN models are established and compared to optimize the neural network structure.After the pre-training and fine-tuning step, the ultimate CNN model reduces the computational cost of the previous kinetic model by over 300 times and predicts the yields of main products with the average error of less than 3%. The obtained results demonstrate the high efficiency of the proposed framework. 展开更多
关键词 convolutional neural NETWORK NETWORK MOTIF NAPHTHA PYROLYSIS KINETIC modeling
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Classification of Arrhythmia Based on Convolutional Neural Networks and Encoder-Decoder Model
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作者 Jian Liu Xiaodong Xia +2 位作者 Chunyang Han Jiao Hui Jim Feng 《Computers, Materials & Continua》 SCIE EI 2022年第10期265-278,共14页
As a common and high-risk type of disease,heart disease seriously threatens people’s health.At the same time,in the era of the Internet of Thing(IoT),smart medical device has strong practical significance for medical... As a common and high-risk type of disease,heart disease seriously threatens people’s health.At the same time,in the era of the Internet of Thing(IoT),smart medical device has strong practical significance for medical workers and patients because of its ability to assist in the diagnosis of diseases.Therefore,the research of real-time diagnosis and classification algorithms for arrhythmia can help to improve the diagnostic efficiency of diseases.In this paper,we design an automatic arrhythmia classification algorithm model based on Convolutional Neural Network(CNN)and Encoder-Decoder model.The model uses Long Short-Term Memory(LSTM)to consider the influence of time series features on classification results.Simultaneously,it is trained and tested by the MIT-BIH arrhythmia database.Besides,Generative Adversarial Networks(GAN)is adopted as a method of data equalization for solving data imbalance problem.The simulation results show that for the inter-patient arrhythmia classification,the hybrid model combining CNN and Encoder-Decoder model has the best classification accuracy,of which the accuracy can reach 94.05%.Especially,it has a better advantage for the classification effect of supraventricular ectopic beats(class S)and fusion beats(class F). 展开更多
关键词 ELECTROENCEPHALOGRAPHY convolutional neural network long short-term memory encoder-decoder model generative adversarial network
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基于CNN模型的地震数据噪声压制性能对比研究 被引量:1
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作者 张光德 张怀榜 +3 位作者 赵金泉 尤加春 魏俊廷 杨德宽 《石油物探》 北大核心 2025年第2期232-246,共15页
地震噪声的压制是地震勘探中地震数据处理的重要研究内容之一。准确地压制地震噪声和提取地震信号中的有效信息是地震勘探和地震监测的一项关键步骤。传统的地震噪声压制方法存在一些不足之处,如灵活性不足、难以处理复杂噪声、有效信... 地震噪声的压制是地震勘探中地震数据处理的重要研究内容之一。准确地压制地震噪声和提取地震信号中的有效信息是地震勘探和地震监测的一项关键步骤。传统的地震噪声压制方法存在一些不足之处,如灵活性不足、难以处理复杂噪声、有效信息损失以及依赖人工提取特征等局限性。为克服传统方法的不足,采用时频域变换并结合深度学习方法进行地震噪声压制,并验证其应用效果。通过构建5个神经网络模型(FCN、Unet、CBDNet、SwinUnet以及TransUnet)对经过时频变换的地震信号进行噪声压制。为了定量评估实验方法的去噪性能,引入了峰值信噪比(PSNR)、结构相似性指数(SSIM)和均方根误差(RMSE)3个指标,比较不同方法的噪声压制性能。数值实验结果表明,基于时频变换的卷积神经网络(CNN)方法对常见的地震噪声类型(包括随机噪声、海洋涌浪噪声、陆地面波噪声)具有较好的噪声压制效果,能够提高地震数据的信噪比。而Transformer模块的引入可进一步提高对上述3种常见地震数据噪声类型的压制效果,进一步提升CNN模型的去噪性能。尽管该方法在数值实验中取得了较好的应用效果,但仍有进一步优化的空间可供探索,比如改进网络结构以适应更复杂的地震信号,并探索与其他先进技术结合,以提升地震噪声压制性能。 展开更多
关键词 地震噪声压制 深度学习 卷积神经网络(cnn) 时频变换 TRANSFORMER
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基于CNN-LSTM-Attention 组合模型的黄金周旅游客流预测——以大理州为例 被引量:1
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作者 戢晓峰 郭雅诗 +2 位作者 陈方 黄志文 李武 《干旱区资源与环境》 北大核心 2025年第3期200-208,共9页
黄金周旅游客流预测一直是区域旅游管理的重大现实需求,能够为黄金周旅游组织提供更为精准的数据支持。文中基于百度迁徙数据和百度搜索指数数据,以卷积神经网络(CNN)、长短期记忆网络(LSTM)以及注意力机制(Attention)为基准,构建了CNN-... 黄金周旅游客流预测一直是区域旅游管理的重大现实需求,能够为黄金周旅游组织提供更为精准的数据支持。文中基于百度迁徙数据和百度搜索指数数据,以卷积神经网络(CNN)、长短期记忆网络(LSTM)以及注意力机制(Attention)为基准,构建了CNN-LSTM-Attention组合模型,对大理州黄金周日度旅游客流人数进行了预测,并基于SHAP算法进行了影响因素分析。结果显示:1)CNN-LSTM-Attention组合模型的预测精度优于RF模型、SVM模型、CNN模型、LSTM模型和CNN-LSTM模型。2)引入百度搜索指数特征后,模型的均方根误差(RMSE)、平均绝对百分比误差(MAPE)、决定系数(R^(2))表现最优,表明百度搜索指数的加入在一定程度上提升了模型的预测精度。文中所构模型为黄金周旅游客流预测提供了新思路。 展开更多
关键词 客流预测 黄金周 卷积神经网络(cnn) 长短期记忆网络(LSTM) 注意力机制
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具有注意力机制的CNN-GRU模型在风电机组异常状态预警中的应用 被引量:1
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作者 马良玉 胡景琛 +1 位作者 段晓冲 黄日灏 《南京信息工程大学学报》 北大核心 2025年第3期374-383,共10页
针对风电机组长期在恶劣环境中工作导致故障频发的问题,提出一种具有注意力机制的卷积神经网络(CNN)及门控循环单元(GRU)的异常工况预警方法.利用快速密度峰值聚类和局部离群因子算法对风电机组数据采集与监控系统中的异常数据进行清洗... 针对风电机组长期在恶劣环境中工作导致故障频发的问题,提出一种具有注意力机制的卷积神经网络(CNN)及门控循环单元(GRU)的异常工况预警方法.利用快速密度峰值聚类和局部离群因子算法对风电机组数据采集与监控系统中的异常数据进行清洗,结合机理分析及极端梯度提升(XGBoost)算法对特征重要性的评估确定模型的输入输出参数,进而采用具有注意力机制的CNN-GRU模型建立风电机组正常运行工况的性能预测模型.以该预测模型为基础,利用时移滑动窗口构建风电机组状态评价指标,并结合统计学中的区间估计法确定预警阈值,最终实现机组异常工况预警.应用某风电机组真实历史故障数据进行实验,结果表明,本文所提方法能够准确地对异常状态进行提前识别和预警,有利于运维人员及时处理故障,保证机组安全稳定运行. 展开更多
关键词 风电机组 卷积神经网络 门控循环单元 注意力机制 故障预警
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