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Leveraging Opposition-Based Learning in Particle Swarm Optimization for Effective Feature Selection
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作者 Fei Yu Zhenya Diao +3 位作者 Hongrun Wu Yingpin Chen Xuewen Xia Yuanxiang Li 《Computers, Materials & Continua》 2026年第4期1148-1179,共32页
Feature selection serves as a critical preprocessing step inmachine learning,focusing on identifying and preserving the most relevant features to improve the efficiency and performance of classification algorithms.Par... Feature selection serves as a critical preprocessing step inmachine learning,focusing on identifying and preserving the most relevant features to improve the efficiency and performance of classification algorithms.Particle Swarm Optimization has demonstrated significant potential in addressing feature selection challenges.However,there are inherent limitations in Particle Swarm Optimization,such as the delicate balance between exploration and exploitation,susceptibility to local optima,and suboptimal convergence rates,hinder its performance.To tackle these issues,this study introduces a novel Leveraged Opposition-Based Learning method within Fitness Landscape Particle Swarm Optimization,tailored for wrapper-based feature selection.The proposed approach integrates:(1)a fitness-landscape adaptive strategy to dynamically balance exploration and exploitation,(2)the lever principle within Opposition-Based Learning to improve search efficiency,and(3)a Local Selection and Re-optimization mechanism combined with random perturbation to expedite convergence and enhance the quality of the optimal feature subset.The effectiveness of is rigorously evaluated on 24 benchmark datasets and compared against 13 advancedmetaheuristic algorithms.Experimental results demonstrate that the proposed method outperforms the compared algorithms in classification accuracy on over half of the datasets,whilst also significantly reducing the number of selected features.These findings demonstrate its effectiveness and robustness in feature selection tasks. 展开更多
关键词 Feature selection fitness landscape opposition-based learning principle of the lever particle swarm optimization
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Effective Deep Learning Models for the Semantic Segmentation of 3D Human MRI Kidney Images
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作者 Roshni Khedgaonkar Pravinkumar Sonsare +5 位作者 Kavita Singh Ayman Altameem Hameed R.Farhan Salil Bharany Ateeq Ur Rehman Ahmad Almogren 《Computers, Materials & Continua》 2026年第4期667-684,共18页
Recent studies indicate that millions of individuals suffer from renal diseases,with renal carcinoma,a type of kidney cancer,emerging as both a chronic illness and a significant cause of mortality.Magnetic Resonance I... Recent studies indicate that millions of individuals suffer from renal diseases,with renal carcinoma,a type of kidney cancer,emerging as both a chronic illness and a significant cause of mortality.Magnetic Resonance Imaging(MRI)and Computed Tomography(CT)have become essential tools for diagnosing and assessing kidney disorders.However,accurate analysis of thesemedical images is critical for detecting and evaluating tumor severity.This study introduces an integrated hybrid framework that combines three complementary deep learning models for kidney tumor segmentation from MRI images.The proposed framework fuses a customized U-Net and Mask R-CNN using a weighted scheme to achieve semantic and instance-level segmentation.The fused outputs are further refined through edge detection using Stochastic FeatureMapping Neural Networks(SFMNN),while volumetric consistency is ensured through Improved Mini-Batch K-Means(IMBKM)clustering integrated with an Encoder-Decoder Convolutional Neural Network(EDCNN).The outputs of these three stages are combined through a weighted fusion mechanism,with optimal weights determined empirically.Experiments on MRI scans from the TCGA-KIRC dataset demonstrate that the proposed hybrid framework significantly outperforms standalone models,achieving a Dice Score of 92.5%,an IoU of 87.8%,a Precision of 93.1%,a Recall of 90.8%,and a Hausdorff Distance of 2.8 mm.These findings validate that the weighted integration of complementary architectures effectively overcomes key limitations in kidney tumor segmentation,leading to improved diagnostic accuracy and robustness in medical image analysis. 展开更多
关键词 Kidney tumor(Blob)segmentation customU-Net andmask R-CNN stochastic featuremapping neural networks medical image analysis deep learning
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Accurate prediction of magnetocaloric effect in NiMn-based Heusler alloys by prioritizing phase transitions through explainable machine learning 被引量:2
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作者 Yi-Chuan Tang Kai-Yan Cao +7 位作者 Ruo-Nan Ma Jia-Bin Wang Yin Zhang Dong-Yan Zhang Chao Zhou Fang-Hua Tian Min-Xia Fang Sen Yang 《Rare Metals》 2025年第1期639-651,共13页
With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase t... With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase transitions into account,and as a result,the predictions are usually not accurate enough.In this context,we have established an explicable relationship between alloy compositions and phase transition by feature imputation.A facile machine learning is proposed to screen candidate NiMn-based Heusler alloys with desired magnetic entropy change and magnetic transition temperature with a high accuracy R^(2)≈0.98.As expected,the measured properties of prepared NiMn-based alloys,including phase transition type,magnetic entropy changes and transition temperature,are all in good agreement with the ML predictions.As well as being the first to demonstrate an explicable relationship between alloy compositions,phase transitions and magnetocaloric properties,our proposed ML model is highly predictive and interpretable,which can provide a strong theoretical foundation for identifying high-performance magnetocaloric materials in the future. 展开更多
关键词 NiMn-based Heusler materials Phase transition-type Machine learning Magnetocaloric effect Composition design
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Statistics and Analysis on the Learning Effect of Virtual Reality Technology Course
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作者 Liangquan He Nan Chen 《Journal of Contemporary Educational Research》 2025年第8期328-336,共9页
With the rapid development of artificial intelligence technology,the development of virtual reality technology has received increasing attention in various fields.Based on the difficulties in the course construction o... With the rapid development of artificial intelligence technology,the development of virtual reality technology has received increasing attention in various fields.Based on the difficulties in the course construction of“Virtual Reality Technology”,this paper adopts a questionnaire survey method to study the learning effects of students majoring in digital media technology at Guangxi University of Finance and Economics regarding the“Virtual Reality Technology”course.The research mainly involves four aspects:learning content,teaching effectiveness,learning experience,and future development needs.The research analysis in this paper not only provides strong support for the construction of a first-class course in“Virtual Reality Technology”but also offers references for the course construction of digital media technology majors in other universities. 展开更多
关键词 Virtual Reality Technology Course construction learning effect
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Inspires effective alternatives to backpropagation:predictive coding helps understand and build learning
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作者 Zhenghua Xu Miao Yu Yuhang Song 《Neural Regeneration Research》 SCIE CAS 2025年第11期3215-3216,共2页
Artificial neural networks are capable of machine learning by simulating the hiera rchical structure of the human brain.To enable learning by brain and machine,it is essential to accurately identify and correct the pr... Artificial neural networks are capable of machine learning by simulating the hiera rchical structure of the human brain.To enable learning by brain and machine,it is essential to accurately identify and correct the prediction errors,referred to as credit assignment(Lillicrap et al.,2020).It is critical to develop artificial intelligence by understanding how the brain deals with credit assignment in neuroscience. 展开更多
关键词 ASSIGNMENT learning enable
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Primordial hydrogen partitioning at Earth’s core-mantle boundary:Multicomponent effects revealed by machine learning-augmented first-principles simulations 被引量:1
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作者 ZePing Jiang YuYang He ZhiGang Zhang 《Earth and Planetary Physics》 2025年第5期1001-1009,共9页
Hydrogen partitioning between liquid iron alloys and silicate melts governs its distribution and cycling in Earth’s deep interior.Existing models based on simplified Fe-H systems predict strong hydrogen sequestration... Hydrogen partitioning between liquid iron alloys and silicate melts governs its distribution and cycling in Earth’s deep interior.Existing models based on simplified Fe-H systems predict strong hydrogen sequestration into the core.However,these models do not account for the modulating effects of major light elements such as oxygen and silicon in the core during Earth’s primordial differentiation.In this study,we use first-principles molecular dynamics simulations,augmented by machine learning techniques,to quantify hydrogen chemical potentials in quaternary Fe-O-Si-H systems under early core-mantle boundary conditions(135 GPa,5000 K).Our results demonstrate that the presence of 5.2 wt%oxygen and 4.8 wt%silicon reduces the siderophile affinity of hydrogen by 35%,decreasing its alloy-silicate partition coefficient from 18.2(in the case of Fe-H)to 11.8(in the case of Fe-O-Si-H).These findings suggest that previous estimates of the core hydrogen content derived from binary system models require downward revision.Our study underscores the critical role of multicomponent interactions in core formation models and provides first-principles-derived constraints to reconcile Earth’s present-day hydrogen reservoirs with its accretionary history. 展开更多
关键词 partition coefficient HYDROGEN core-mantle differentiation light elements machine learning density functional theory
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Topology-based machine learning for predicting curvature effects in metal-nitrogen-carbon single-atom catalysts
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作者 Ge-Hao Liang Heng-Su Liu +2 位作者 Xi-Ming Zhang Jian-Feng Li Shisheng Zheng 《Journal of Energy Chemistry》 2025年第6期608-616,I0014,共10页
Metal-nitrogen-carbon(M-N-C)single-atom catalysts are widely utilized in various energy-related catalytic processes,offering a highly efficient and cost-effective catalytic system with significant potential.Recently,c... Metal-nitrogen-carbon(M-N-C)single-atom catalysts are widely utilized in various energy-related catalytic processes,offering a highly efficient and cost-effective catalytic system with significant potential.Recently,curvature-induced strain has been extensively demonstrated as a powerful tool for modulating the catalytic performance of M-N-C catalysts.However,identifying optimal strain patterns using density functional theory(DFT)is computationally intractable due to the high-dimensional search space.Here,we developed a graph neural network(GNN)integrated with an advanced topological data analysis tool-persistent homology-to predict the adsorption energy response of adsorbate under proposed curvature patterns,using nitric oxide electroreduction(NORR)as an example.Our machine learning model achieves high accuracy in predicting the adsorption energy response to curvature,with a mean absolute error(MAE)of 0.126 eV.Furthermore,we elucidate general trends in curvature-modulated adsorption energies of intermediates across various metals and coordination environments.We recommend several promising catalysts for NORR that exhibit significant potential for performance optimization via curvature modulation.This methodology can be readily extended to describe other non-bonded interactions,such as lattice strain and surface stress,providing a versatile approach for advanced catalyst design. 展开更多
关键词 Curvature effect Persistent homology Machine learning Single-atom catalyst Nitricoxide electroreduction
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Machine learning-based comparison of transperineal vs.transrectal biopsy for prostate cancer diagnosis:evaluating procedural effectiveness
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作者 Mostafa Ahmed Arafa Karim Hamda Farhat +7 位作者 Nesma Lotfy Farrukh Kamel Khan Alaa Mokhtar Abdulaziz Mohammed Althunayan Waleed Al-Taweel Sultan Saud Al-Khateeb Sami Azhari Danny Munther Rabah 《The Canadian Journal of Urology》 2025年第3期173-180,共8页
Background:Transrectal(TR)and transperineal(TP)biopsies are commonly used methods for diagnosing prostate cancer.However,their comparative effectiveness in conjunction with machine learning(ML)techniques remains under... Background:Transrectal(TR)and transperineal(TP)biopsies are commonly used methods for diagnosing prostate cancer.However,their comparative effectiveness in conjunction with machine learning(ML)techniques remains underexplored.This study aimed to evaluate the predictive accuracy of ML algorithms in detecting prostate cancer using data derived from TR and TP biopsies.Methods:The clinical records of patients who underwent prostate biopsy at King Saud University Medical City and King Faisal Specialist Hospital and Research Centerin Riyadh,Saudi Arabia,between 2018 and 2025 were analyzed.Data were used to train and testMLmodels,including eXtreme Gradient Boosting(XGBoost),Decision Tree,Random Forest,and Extra Trees.Results:The two datasets are comparable.The models demonstrated exceptional performance,achieving accuracies of up to 96.49%and 95.56%on TP and TR biopsy datasets,respectively.The area under the curve(AUC)values were also high,reaching 0.9988 for TP and 0.9903 for TR biopsy predictions.Conclusion:These findings highlight the potential of MLto enhance the diagnostic accuracy of prostate cancer detection irrespective of the biopsy method.However,TP biopsy data showed marginally higher accuracy,possibly because of the lower risk of contamination.While ML holds great promise for transforming prostate cancer care,further research is needed to address limitations.Collaboration between clinicians,data scientists,and researchers is crucial to ensure the clinical relevance and interpretability of ML models. 展开更多
关键词 machine learning prediction effectiveness prostate cancer transperineal biopsy transrectal biopsy
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Machine learning-based investigation of uplift resistance in special-shaped shield tunnels using numerical finite element modeling 被引量:1
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作者 ZHANG Wengang YE Wenyu +2 位作者 SUN Weixin LIU Zhicheng LI Zhengchuan 《土木与环境工程学报(中英文)》 北大核心 2026年第1期1-13,共13页
The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combi... The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combines numerical simulation with machine learning techniques to explore this issue.It presents a summary of special-shaped tunnel geometries and introduces a shape coefficient.Through the finite element software,Plaxis3D,the study simulates six key parameters—shape coefficient,burial depth ratio,tunnel’s longest horizontal length,internal friction angle,cohesion,and soil submerged bulk density—that impact uplift resistance across different conditions.Employing XGBoost and ANN methods,the feature importance of each parameter was analyzed based on the numerical simulation results.The findings demonstrate that a tunnel shape more closely resembling a circle leads to reduced uplift resistance in the overlying soil,whereas other parameters exhibit the contrary effects.Furthermore,the study reveals a diminishing trend in the feature importance of buried depth ratio,internal friction angle,tunnel longest horizontal length,cohesion,soil submerged bulk density,and shape coefficient in influencing uplift resistance. 展开更多
关键词 special-shaped tunnel shield tunnel uplift resistance numerical simulation machine learning
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Quantification of backwater effect in Jingjiang Reach due to confluence with Dongting Lake using a machine learning model
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作者 Hai-xin Shang Jun-qiang Xia +2 位作者 Chun-hong Hu Mei-rong Zhou Shan-shan Deng 《Water Science and Engineering》 2025年第2期187-199,共13页
The backwater effect caused by tributary inflow can significantly elevate the water level profile upstream of a confluence point.However,the influence of mainstream and confluence discharges on the backwater effect in... The backwater effect caused by tributary inflow can significantly elevate the water level profile upstream of a confluence point.However,the influence of mainstream and confluence discharges on the backwater effect in a river reach remains unclear.In this study,various hydrological data collected from the Jingjiang Reach of the Yangtze River in China were statistically analyzed to determine the backwater degree and range with three representative mainstream discharges.The results indicated that the backwater degree increased with mainstream discharge,and a positive relationship was observed between the runoff ratio and backwater degree at specific representative mainstream discharges.Following the operation of the Three Gorges Project,the backwater effect in the Jingjiang Reach diminished.For instance,mean backwater degrees for low,moderate,and high mainstream discharges were recorded as 0.83 m,1.61 m,and 2.41 m during the period from 1990 to 2002,whereas these values decreased to 0.30 m,0.95 m,and 2.08 m from 2009 to 2020.The backwater range extended upstream as mainstream discharge increased from 7000 m3/s to 30000 m3/s.Moreover,a random forest-based machine learning model was used to quantify the backwater effect with varying mainstream and confluence discharges,accounting for the impacts of mainstream discharge,confluence discharge,and channel degradation in the Jingjiang Reach.At the Jianli Hydrological Station,a decrease in mainstream discharge during flood seasons resulted in a 7%–15%increase in monthly mean backwater degree,while an increase in mainstream discharge during dry seasons led to a 1%–15%decrease in monthly mean backwater degree.Furthermore,increasing confluence discharge from Dongting Lake during June to July and September to November resulted in an 11%–42%increase in monthly mean backwater degree.Continuous channel degradation in the Jingjiang Reach contributed to a 6%–19%decrease in monthly mean backwater degree.Under the influence of these factors,the monthly mean backwater degree in 2017 varied from a decrease of 53%to an increase of 37%compared to corresponding values in 1991. 展开更多
关键词 Backwater effect Stage-discharge relationship Machine learning model Dongting Lake confluence Jingjiang reach
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Effect of preprocessing on performances of machine learning-based mineral composition analysis on gas hydrate sediments,Ulleung Basin,East Sea 被引量:1
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作者 Hongkeun Jin Ju Young Park +3 位作者 Sun Young Park Byeong-Kook Son Baehyun Min Kyungbook Lee 《Petroleum Science》 2025年第1期151-162,共12页
Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-... Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-scale drilling expeditions to study the GH-bearing zone in the Ulleung Basin,the mineral composition of 488 sediment samples was analyzed using X-ray diffraction(XRD).Because the analysis is costly and dependent on experts,a machine learning model was developed to predict the mineral composition using XRD intensity profiles as input data.However,the model’s performance was limited because of improper preprocessing of the intensity profile.Because preprocessing was applied to each feature,the intensity trend was not preserved even though this factor is the most important when analyzing mineral composition.In this study,the profile was preprocessed for each sample using min-max scaling because relative intensity is critical for mineral analysis.For 49 test data among the 488 data,the convolutional neural network(CNN)model improved the average absolute error and coefficient of determination by 41%and 46%,respectively,than those of CNN model with feature-based pre-processing.This study confirms that combining preprocessing for each sample with CNN is the most efficient approach for analyzing XRD data.The developed model can be used for the compositional analysis of sediment samples from the Ulleung Basin and the Korea Plateau.In addition,the overall procedure can be applied to any XRD data of sediments worldwide. 展开更多
关键词 Sample-based preprocessing X-ray diffraction(XRD) Machine learning Mineral composition Gas hydrate(GH) Ulleung basin
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Using deep learning to reduce nonlinearity effects in nearinfrared spectroscopy for accurate quantification of tobacco leaf pectin concentrations
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作者 Wenhui Yang Limin Shao 《中国科学技术大学学报》 北大核心 2025年第6期57-66,56,I0002,共12页
In the near-infrared(NIR)spectroscopic data of complex sample systems,such as tobacco leaves,nonlinearity is fairly significant between the absorbance and concentration.This nonlinearity severely degrades the quantita... In the near-infrared(NIR)spectroscopic data of complex sample systems,such as tobacco leaves,nonlinearity is fairly significant between the absorbance and concentration.This nonlinearity severely degrades the quantitative results of traditional methods,such as partial least squares regression(PLS),which can be used to construct linear models.The problem was addressed in this study by using deep learning(DL).We employed three different DL models:a one-dimensional convolutional neural network(1D CNN),a deep neural network(DNN),and a stacked autoencoder with feedforward neural networks(SAE-FNNs).By carefully selecting and tuning the architectures and parameters of these models,we were able to find the most suitable model for dealing with such nonlinear relationships.Our experimental findings reveal that both the DNN and the SAE-FNN models excel in addressing the nonlinear issues of pectin concentration in tobacco,surpassing the performance of the classic linear model(PLS).Specifically,the DNN model stands out for its low average root mean squared error of prediction(RMSEP)value and small standard deviation(SD)of RMSEPs,leading to a tighter and more centered distribution of residuals in the prediction set.These DL models not only proficiently identify complex patterns within NIR data but also boast high prediction accuracy and fast implementation,demonstrating their effectiveness in analytical applications. 展开更多
关键词 quantitative regression NONLINEARITY deep learning methods near-infrared spectroscopy
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Can reinforcement learning effectively prevent depression relapse?
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作者 Haewon Byeon 《World Journal of Psychiatry》 2025年第8期71-79,共9页
Depression is a prevalent mental health disorder characterized by high relapse rates,highlighting the need for effective preventive interventions.This paper reviews the potential of reinforcement learning(RL)in preven... Depression is a prevalent mental health disorder characterized by high relapse rates,highlighting the need for effective preventive interventions.This paper reviews the potential of reinforcement learning(RL)in preventing depression relapse.RL,a subset of artificial intelligence,utilizes machine learning algorithms to analyze behavioral data,enabling early detection of relapse risk and optimization of personalized interventions.RL's ability to tailor treatment in real-time by adapting to individual needs and responses offers a dynamic alternative to traditional therapeutic approaches.Studies have demonstrated the efficacy of RL in customizing e-Health interventions and integrating mobile sensing with machine learning for adaptive mental health systems.Despite these advantages,challenges remain in algorithmic complexity,ethical considerations,and clinical implementation.Addressing these issues is crucial for the successful integration of RL into mental health care.This paper concludes with recommendations for future research directions,emphasizing the need for larger-scale studies and interdisciplinary collaboration to fully realize RL’s potential in improving mental health outcomes and preventing depression relapse. 展开更多
关键词 Reinforcement learning Depression relapse prevention Personalized treatment Machine learning Mental health interventions
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Analysing Effectiveness of Sentiments in Social Media Data Using Machine Learning Techniques
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作者 Thambusamy Velmurugan Mohandas Archana Ajith Singh Nongmaithem 《Journal of Computer and Communications》 2025年第1期136-151,共16页
Every second, a large volume of useful data is created in social media about the various kind of online purchases and in another forms of reviews. Particularly, purchased products review data is enormously growing in ... Every second, a large volume of useful data is created in social media about the various kind of online purchases and in another forms of reviews. Particularly, purchased products review data is enormously growing in different database repositories every day. Most of the review data are useful to new customers for theier further purchases as well as existing companies to view customers feedback about various products. Data Mining and Machine Leaning techniques are familiar to analyse such kind of data to visualise and know the potential use of the purchased items through online. The customers are making quality of products through their sentiments about the purchased items from different online companies. In this research work, it is analysed sentiments of Headphone review data, which is collected from online repositories. For the analysis of Headphone review data, some of the Machine Learning techniques like Support Vector Machines, Naive Bayes, Decision Trees and Random Forest Algorithms and a Hybrid method are applied to find the quality via the customers’ sentiments. The accuracy and performance of the taken algorithms are also analysed based on the three types of sentiments such as positive, negative and neutral. 展开更多
关键词 Support Vector Machine Random Forest Algorithm Naive Bayes Algorithm Machine learning Techniques Decision Tree Algorithm
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Exploring the Effectiveness of Machine Learning and Deep Learning Algorithms for Sentiment Analysis:A Systematic Literature Review
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作者 Jungpil Shin Wahidur Rahman +5 位作者 Tanvir Ahmed Bakhtiar Mazrur Md.Mohsin Mia Romana Idress Ekfa Md.Sajib Rana Pankoo Kim 《Computers, Materials & Continua》 2025年第9期4105-4153,共49页
Sentiment Analysis,a significant domain within Natural Language Processing(NLP),focuses on extracting and interpreting subjective information-such as emotions,opinions,and attitudes-from textual data.With the increasi... Sentiment Analysis,a significant domain within Natural Language Processing(NLP),focuses on extracting and interpreting subjective information-such as emotions,opinions,and attitudes-from textual data.With the increasing volume of user-generated content on social media and digital platforms,sentiment analysis has become essential for deriving actionable insights across various sectors.This study presents a systematic literature review of sentiment analysis methodologies,encompassing traditional machine learning algorithms,lexicon-based approaches,and recent advancements in deep learning techniques.The review follows a structured protocol comprising three phases:planning,execution,and analysis/reporting.During the execution phase,67 peer-reviewed articles were initially retrieved,with 25 meeting predefined inclusion and exclusion criteria.The analysis phase involved a detailed examination of each study’s methodology,experimental setup,and key contributions.Among the deep learning models evaluated,Long Short-Term Memory(LSTM)networks were identified as the most frequently adopted architecture for sentiment classification tasks.This review highlights current trends,technical challenges,and emerging opportunities in the field,providing valuable guidance for future research and development in applications such as market analysis,public health monitoring,financial forecasting,and crisis management. 展开更多
关键词 Natural Language Processing(NLP) Machine learning(ML) sentiment analysis deep learning textual data
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Effective and efficient handling of missing data in supervised machine learning
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作者 Peter Ayokunle Popoola Jules-Raymond Tapamo Alain Guy HonoréAssounga 《Data Science and Management》 2025年第3期361-373,共13页
The prevailing consensus in statistical literature is that multiple imputation is generally the most suitable method for addressing missing data in statistical analyses,whereas a complete case analysis is deemed appro... The prevailing consensus in statistical literature is that multiple imputation is generally the most suitable method for addressing missing data in statistical analyses,whereas a complete case analysis is deemed appropriate only when the rate of missingness is negligible or when the missingness mechanism is missing completely at random(MCAR).This study investigates the applicability of this consensus within the context of supervised machine learning,with particular emphasis on the interactions between the imputation method,missingness mechanism,and missingness rate.Furthermore,we examine the time efficiency of these“state-of-the-art”imputation methods considering the time-sensitive nature of certain machine learning applications.Utilizing ten real-world datasets,we introduced missingness at rates ranging from approximately 5%–75%under the MCAR,missing at random(MAR),and missing not at random(MNAR)mechanisms.We subsequently address missing data using five methods:complete case analysis(CCA),mean imputation,hot deck imputation,regression imputation,and multiple imputation(MI).Statistical tests are conducted on the machine learning outcomes,and the findings are presented and analyzed.Our investigation reveals that in nearly all scenarios,CCA performs comparably to MI,even with substantial levels of missingness under the MAR and MNAR conditions and with missingness in the output variable for regression problems.Under some conditions,CCA surpasses MI in terms of its performance.Thus,given the considerable computational demands associated with MI,the application of CCA is recommended within the broader context of supervised machine learning,particularly in big-data environments. 展开更多
关键词 CLASSIFICATION IMPUTATION learning Missing data Prediction
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Quantifying Global Black Carbon Aging Responses to Emission Reductions Using a Machine Learning-based Climate Model 被引量:1
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作者 Wenxiang SHEN Minghuai WANG +5 位作者 Junchang WANG Yawen LIU Xinyi DONG Xinyue SHAO Man YUE Yaman LIU 《Advances in Atmospheric Sciences》 2026年第2期361-372,I0004-I0009,共18页
Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model versi... Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model version 6 with a machine-learning-integrated four-mode version of the Modal Aerosol Module, we quantify global BC aging responses to emission reductions for 2011–2018 and for 2050 and 2100 under carbon neutrality. During 2011–18, global trends in BC aging degree(mass ratio of coatings to BC, R_(BC)) exhibited marked regional disparities, with a significant increase in China(5.4% yr^(-1)), which contrasts with minimal changes in the USA, Europe, and India. The divergence is attributed to opposing trends in secondary organic aerosol(SOA) and sulfate coatings, driven by regional changes in the emission ratios of corresponding coating precursors to BC(volatile organic compounds-VOCs/BC and SO_(2)/BC). Projections under carbon neutrality reveal that R_(BC) will increase globally by 47%(118%) in 2050(2100), with strong convergent increases expected across major source regions. The R_(BC) increase, primarily driven by enhanced SOA coatings due to sharper BC reductions relative to VOCs, will enhance the global BC mass absorption cross-section(MAC) by 11%(17%) in 2050(2100).Consequently, although the global BC burden will decline sharply by 60%(76%), the enhanced MAC partially offsets the magnitude of the decline in the BC direct radiative effect, resulting in the moderation of global BC DRE decreases to 88%(92%) of the BC burden reductions in 2050(2100). This study highlights the globally enhanced BC aging and light absorption capacity under carbon neutrality, thereby partly offsetting the impact of BC direct emission reductions on future changes in BC radiative effects globally. 展开更多
关键词 black carbon aging trend emission reduction carbon neutrality machine learning
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PowerVLM:基于Federated Learning与模型剪枝的电力视觉语言大模型
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作者 欧阳旭东 雒鹏鑫 +3 位作者 何绍洋 崔艺林 张中超 闫云凤 《全球能源互联网》 北大核心 2026年第1期101-111,共11页
智能电网的快速发展衍生出多模态、多源异构的海量电力数据,给人工智能模型在复杂电力场景感知带来了挑战,同时行业数据的敏感性和隐私保护需求进一步限制了通用模型在电力领域的跨场景迁移能力。对此,提出了一种基于Federated Learnin... 智能电网的快速发展衍生出多模态、多源异构的海量电力数据,给人工智能模型在复杂电力场景感知带来了挑战,同时行业数据的敏感性和隐私保护需求进一步限制了通用模型在电力领域的跨场景迁移能力。对此,提出了一种基于Federated Learning与模型剪枝的电力视觉语言大模型。提出了一种基于类别引导的电力视觉语言大模型PowerVLM,设计了类别引导增强模块,增强模型对电力图文数据的理解和问答能力;采用FL的强化学习训练策略,在满足数据隐私保护下,降低域间差异对模型性能的影响;最后,提出了一种基于信息决议的模型剪枝算法,可实现低训练参数的模型高效微调。分别在变电巡检、输电任务、作业安监3种典型电力场景开展实验,结果表明,该方法在电力场景多模态问答任务中的METEOR、BLEU和CIDEr等各项指标均表现优异,为电力场景智能感知提供了新的技术思路和方法支撑。 展开更多
关键词 智能电网 人工智能 视觉语言大模型 Federated learning 模型剪枝
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Rapid prediction of effective absorption bandwidth in PEEK/CF additive manufacturing metastructure via interpretable machine learning
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作者 Shuailong Gao Huaiyu Dong +6 位作者 Yuhui Zhang Yingjian Sun Chen Yu Zhichen Wang Haofeng Zhang Yixing Huang Ying Li 《Journal of Materials Science & Technology》 2025年第36期307-319,共13页
The development of machine learning has provided a new perspective for the design of electromagnetic metastructures,particularly in the rapid design of key performance metrics such as effective absorption bandwidth.Tr... The development of machine learning has provided a new perspective for the design of electromagnetic metastructures,particularly in the rapid design of key performance metrics such as effective absorption bandwidth.Traditional methods,grounded in electromagnetic theory and empirical approaches,often lacked sufficient flexibility and adaptability.In this work,three types of machine learning models were developed to establish the relationship between effective absorption bandwidth and structural parameters.The results indicated that the random forest model achieved the most accurate and efficient design for this task.Then,the additive manufacturing optimal metastructure obtained using this approach outperformed existing designs in terms of both effective absorption bandwidth and reflectivity,while also exhibiting superior radar stealth performance and mechanical load-bearing capacity.Furthermore,through interpretable machine learning and data analysis,the intrinsic mechanisms underlying the relationship between effective absorption bandwidth and structural parameters were revealed.Overall,this work introduced a novel approach to metastructure design and enhanced the understanding of the relationship between structural parameters and electromagnetic properties,providing a key foundation for future design. 展开更多
关键词 Rapid design Electromagnetic metastructure Machine learning Additive Manufacturing
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Enhancing triboelectrification with synergistic effect of x BNT-(1−x)BKT fillers and machine learning enabled advanced air mouse technology
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作者 Monunith Anithkumar Nirmal Prashanth Maria Joseph Raj +2 位作者 Asokan Poorani Sathya Prasanna Thanjan Shaji Bincy Sang-Jae Kim 《Journal of Materials Science & Technology》 2025年第28期105-114,共10页
Air mouse has a wide range of uses in robotics,automation,and VR/AR technologies.In this work,the air mouse is prepared using triboelectric sensors,controller units,and machine learning.The triboelectric nanogenerator... Air mouse has a wide range of uses in robotics,automation,and VR/AR technologies.In this work,the air mouse is prepared using triboelectric sensors,controller units,and machine learning.The triboelectric nanogenerator(TENG)performance was optimized by altering the filler’s properties.A dual-ferroelectric crystal system BNKT(xBi_(0.5) Na_(0.5) TiO_(3)-(1−x)Bi_(0.5) K_(0.5) TiO_(3))was prepared with different concentrations(x=_(0.5),0.6,0.7,0.8,and 0.9)to alter the dielectric property.The BNKT-8-based TENG showed a higher performance of 134.04 V and 1.49μA.The prepared device enables to power the small electronic devices such as hygrometers and calculators.Using this TENG device air mouse system with machine learning allows the user to control the mouse pointer in the computer using the smart glove with a high accuracy of 100%. 展开更多
关键词 Triboelectric nanogenerator Dielectric materials Air mouse Machine learning
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