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A Convolutional Neural Network-Based Deep Support Vector Machine for Parkinson’s Disease Detection with Small-Scale and Imbalanced Datasets
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作者 Kwok Tai Chui Varsha Arya +2 位作者 Brij B.Gupta Miguel Torres-Ruiz Razaz Waheeb Attar 《Computers, Materials & Continua》 2026年第1期1410-1432,共23页
Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using d... Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using deep learning algorithms further enhances performance;nevertheless,it is challenging due to the nature of small-scale and imbalanced PD datasets.This paper proposed a convolutional neural network-based deep support vector machine(CNN-DSVM)to automate the feature extraction process using CNN and extend the conventional SVM to a DSVM for better classification performance in small-scale PD datasets.A customized kernel function reduces the impact of biased classification towards the majority class(healthy candidates in our consideration).An improved generative adversarial network(IGAN)was designed to generate additional training data to enhance the model’s performance.For performance evaluation,the proposed algorithm achieves a sensitivity of 97.6%and a specificity of 97.3%.The performance comparison is evaluated from five perspectives,including comparisons with different data generation algorithms,feature extraction techniques,kernel functions,and existing works.Results reveal the effectiveness of the IGAN algorithm,which improves the sensitivity and specificity by 4.05%–4.72%and 4.96%–5.86%,respectively;and the effectiveness of the CNN-DSVM algorithm,which improves the sensitivity by 1.24%–57.4%and specificity by 1.04%–163%and reduces biased detection towards the majority class.The ablation experiments confirm the effectiveness of individual components.Two future research directions have also been suggested. 展开更多
关键词 Convolutional neural network data generation deep support vector machine feature extraction generative artificial intelligence imbalanced dataset medical diagnosis Parkinson’s disease small-scale dataset
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Layered Feature Engineering for E-Commerce Purchase Prediction:A Hierarchical Evaluation on Taobao User Behavior Datasets
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作者 Liqiu Suo Lin Xia +1 位作者 Yoona Chung Eunchan Kim 《Computers, Materials & Continua》 2026年第4期1865-1889,共25页
Accurate purchase prediction in e-commerce critically depends on the quality of behavioral features.This paper proposes a layered and interpretable feature engineering framework that organizes user signals into three ... Accurate purchase prediction in e-commerce critically depends on the quality of behavioral features.This paper proposes a layered and interpretable feature engineering framework that organizes user signals into three layers:Basic,Conversion&Stability(efficiency and volatility across actions),and Advanced Interactions&Activity(crossbehavior synergies and intensity).Using real Taobao(Alibaba’s primary e-commerce platform)logs(57,976 records for 10,203 users;25 November–03 December 2017),we conducted a hierarchical,layer-wise evaluation that holds data splits and hyperparameters fixed while varying only the feature set to quantify each layer’s marginal contribution.Across logistic regression(LR),decision tree,random forest,XGBoost,and CatBoost models with stratified 5-fold cross-validation,the performance improvedmonotonically fromBasic to Conversion&Stability to Advanced features.With LR,F1 increased from 0.613(Basic)to 0.962(Advanced);boosted models achieved high discrimination(0.995 AUC Score)and an F1 score up to 0.983.Calibration and precision–recall analyses indicated strong ranking quality and acknowledged potential dataset and period biases given the short(9-day)window.By making feature contributions measurable and reproducible,the framework complements model-centric advances and offers a transparent blueprint for production-grade behavioralmodeling.The code and processed artifacts are publicly available,and future work will extend the validation to longer,seasonal datasets and hybrid approaches that combine automated feature learning with domain-driven design. 展开更多
关键词 Hierarchical feature engineering purchase prediction user behavior dataset feature importance e-commerce platform TAOBAO
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Fine-Med-Mental-T&P:a dual-track approach for high-quality instructional datasets of mental disorders in traditional Chinese medicine
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作者 Yanbai Wei Xiaoshuo Jing Junfeng Yan 《Digital Chinese Medicine》 2026年第1期31-42,共12页
Objective To investigate methods for constructing a high-quality instructional dataset for traditional Chinese medicine(TCM)mental disorders and to validate its efficacy.Methods We proposed the Fine-Med-Mental-T&P... Objective To investigate methods for constructing a high-quality instructional dataset for traditional Chinese medicine(TCM)mental disorders and to validate its efficacy.Methods We proposed the Fine-Med-Mental-T&P methodology for constructing high-quality instruction datasets in TCM mental disorders.This approach integrates theoretical knowledge and practical case studies through a dual-track strategy.(i)Theoretical track:textbooks and guidelines on TCM mental disorders were manually segmented.Initial responses were generated using DeepSeek-V3,followed by refinement by the Qwen3-32B model to align the expression with human preferences.A screening algorithm was then applied to select 16000 high-quality instruction pairs.(ii)Practical track:starting from over 600 real clinical case seeds,diagnostic and therapeutic instruction pairs were generated using DeepSeek-V3 and subsequently screened through manual evaluation,resulting in 4000 high-quality practiceoriented instruction pairs.The integration of both tracks yielded the Med-Mental-Instruct-T&P dataset,comprising a total of 20000 instruction pairs.To validate the dataset’s effectiveness,three experimental evaluations(both manual and automated)were conducted:(i)comparative studies to compare the performance of models fine-tuned on different datasets;(ii)benchmarking to compare against mainstream TCM-specific large language models(LLMs);(iii)data ablation study to investigate the relationship between data volume and model performance.Results Experimental results demonstrate the superior performance of T&P-model finetuned on the Med-Mental-Instruct-T&P dataset.In the comparative study,the T&P-model significantly outperformed the baseline models trained solely on self-generated or purely human-curated baseline data.This superiority was evident in both automated metrics(ROUGEL>0.55)and expert manual evaluations(scoring above 7/10 across accuracy).In benchmark comparisons,the T&P-model also excelled against existing mainstream TCM LLMs(e.g.,HuatuoGPT and ZuoyiGPT).It showed particularly strong capabilities in handling diverse clinical presentations,including challenging disorders such as insomnia and coma,showcasing its robustness and versatility.Data ablation studies showed that T&P-model performance had an overall upward trend with minor fluctuations when training data increased from 10%to 50%;beyond 50%,performance improvement slowed significantly,with metrics plateauing and approaching a saturation point. 展开更多
关键词 Mental disorder Traditional Chinese medicine(TCM) Instruction dataset construction Instruction tuning Large language model
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基于TDIM的高精度功率SMD结壳热阻测量技术
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作者 吴玉强 郑花 +3 位作者 马凤丽 侯杰 许为新 郭美洋 《半导体技术》 北大核心 2025年第12期1237-1243,共7页
为解决传统热阻测量中功率表面贴装器件(SMD)散热基板与电学引出端共面导致短路及热电偶法测量误差问题,提出一种基于瞬态双界面法(TDIM)的高精度结壳热阻(R_(θJC))测量技术。通过设计含铜板凸台结构与绝缘定位板的专用夹具,有效避免... 为解决传统热阻测量中功率表面贴装器件(SMD)散热基板与电学引出端共面导致短路及热电偶法测量误差问题,提出一种基于瞬态双界面法(TDIM)的高精度结壳热阻(R_(θJC))测量技术。通过设计含铜板凸台结构与绝缘定位板的专用夹具,有效避免了电气短路;结合TDIM替代热电偶法,消除了热量“芯吸”效应与测温位置误差。以TO-277封装肖特基二极管为实验对象,测得其R_(θJC)为0.302 K/W,与器件手册典型值(0.30 K/W)误差仅0.67%。通过在相同结温(423.15 K)下实施两次热表征,显著抑制了温度依赖性误差。本技术为功率SMD的热管理设计提供了可靠的测量方案,具备工程推广价值。 展开更多
关键词 瞬态双界面法(TDIM) 表面贴装器件(smd) 结壳热阻 专用夹具 热表征 热管理 一维热流路径
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Standardizing Healthcare Datasets in China:Challenges and Strategies
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作者 Zheng-Yong Hu Xiao-Lei Xiu +2 位作者 Jing-Yu Zhang Wan-Fei Hu Si-Zhu Wu 《Chinese Medical Sciences Journal》 2025年第4期253-267,I0001,共16页
Standardized datasets are foundational to healthcare informatization by enhancing data quality and unleashing the value of data elements.Using bibliometrics and content analysis,this study examines China's healthc... Standardized datasets are foundational to healthcare informatization by enhancing data quality and unleashing the value of data elements.Using bibliometrics and content analysis,this study examines China's healthcare dataset standards from 2011 to 2025.It analyzes their evolution across types,applications,institutions,and themes,highlighting key achievements including substantial growth in quantity,optimized typology,expansion into innovative application scenarios such as health decision support,and broadened institutional involvement.The study also identifies critical challenges,including imbalanced development,insufficient quality control,and a lack of essential metadata—such as authoritative data element mappings and privacy annotations—which hampers the delivery of intelligent services.To address these challenges,the study proposes a multi-faceted strategy focused on optimizing the standard system's architecture,enhancing quality and implementation,and advancing both data governance—through authoritative tracing and privacy protection—and intelligent service provision.These strategies aim to promote the application of dataset standards,thereby fostering and securing the development of new productive forces in healthcare. 展开更多
关键词 healthcare dataset standards data standardization data management
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DCS-SOCP-SVM:A Novel Integrated Sampling and Classification Algorithm for Imbalanced Datasets
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作者 Xuewen Mu Bingcong Zhao 《Computers, Materials & Continua》 2025年第5期2143-2159,共17页
When dealing with imbalanced datasets,the traditional support vectormachine(SVM)tends to produce a classification hyperplane that is biased towards the majority class,which exhibits poor robustness.This paper proposes... When dealing with imbalanced datasets,the traditional support vectormachine(SVM)tends to produce a classification hyperplane that is biased towards the majority class,which exhibits poor robustness.This paper proposes a high-performance classification algorithm specifically designed for imbalanced datasets.The proposed method first uses a biased second-order cone programming support vectormachine(B-SOCP-SVM)to identify the support vectors(SVs)and non-support vectors(NSVs)in the imbalanced data.Then,it applies the synthetic minority over-sampling technique(SV-SMOTE)to oversample the support vectors of the minority class and uses the random under-sampling technique(NSV-RUS)multiple times to undersample the non-support vectors of the majority class.Combining the above-obtained minority class data set withmultiple majority class datasets can obtainmultiple new balanced data sets.Finally,SOCP-SVM is used to classify each data set,and the final result is obtained through the integrated algorithm.Experimental results demonstrate that the proposed method performs excellently on imbalanced datasets. 展开更多
关键词 DCS-SOCP-SVM imbalanced datasets sampling method ensemble method integrated algorithm
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A Comprehensive Review of Face Detection Techniques for Occluded Faces:Methods,Datasets,and Open Challenges
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作者 Thaer Thaher Majdi Mafarja +2 位作者 Muhammed Saffarini Abdul Hakim H.M.Mohamed Ayman A.El-Saleh 《Computer Modeling in Engineering & Sciences》 2025年第6期2615-2673,共59页
Detecting faces under occlusion remains a significant challenge in computer vision due to variations caused by masks,sunglasses,and other obstructions.Addressing this issue is crucial for applications such as surveill... Detecting faces under occlusion remains a significant challenge in computer vision due to variations caused by masks,sunglasses,and other obstructions.Addressing this issue is crucial for applications such as surveillance,biometric authentication,and human-computer interaction.This paper provides a comprehensive review of face detection techniques developed to handle occluded faces.Studies are categorized into four main approaches:feature-based,machine learning-based,deep learning-based,and hybrid methods.We analyzed state-of-the-art studies within each category,examining their methodologies,strengths,and limitations based on widely used benchmark datasets,highlighting their adaptability to partial and severe occlusions.The review also identifies key challenges,including dataset diversity,model generalization,and computational efficiency.Our findings reveal that deep learning methods dominate recent studies,benefiting from their ability to extract hierarchical features and handle complex occlusion patterns.More recently,researchers have increasingly explored Transformer-based architectures,such as Vision Transformer(ViT)and Swin Transformer,to further improve detection robustness under challenging occlusion scenarios.In addition,hybrid approaches,which aim to combine traditional andmodern techniques,are emerging as a promising direction for improving robustness.This review provides valuable insights for researchers aiming to develop more robust face detection systems and for practitioners seeking to deploy reliable solutions in real-world,occlusionprone environments.Further improvements and the proposal of broader datasets are required to developmore scalable,robust,and efficient models that can handle complex occlusions in real-world scenarios. 展开更多
关键词 Occluded face detection feature-based deep learning machine learning hybrid approaches datasets
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Impact of climate changes on Arizona State precipitation patterns using high-resolution climatic gridded datasets
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作者 Hayder H.Kareem Shahla Abdulqader Nassrullah 《Journal of Groundwater Science and Engineering》 2025年第1期34-46,共13页
Climate change significantly affects environment,ecosystems,communities,and economies.These impacts often result in quick and gradual changes in water resources,environmental conditions,and weather patterns.A geograph... Climate change significantly affects environment,ecosystems,communities,and economies.These impacts often result in quick and gradual changes in water resources,environmental conditions,and weather patterns.A geographical study was conducted in Arizona State,USA,to examine monthly precipi-tation concentration rates over time.This analysis used a high-resolution 0.50×0.50 grid for monthly precip-itation data from 1961 to 2022,Provided by the Climatic Research Unit.The study aimed to analyze climatic changes affected the first and last five years of each decade,as well as the entire decade,during the specified period.GIS was used to meet the objectives of this study.Arizona experienced 51–568 mm,67–560 mm,63–622 mm,and 52–590 mm of rainfall in the sixth,seventh,eighth,and ninth decades of the second millennium,respectively.Both the first and second five year periods of each decade showed accept-able rainfall amounts despite fluctuations.However,rainfall decreased in the first and second decades of the third millennium.and in the first two years of the third decade.Rainfall amounts dropped to 42–472 mm,55–469 mm,and 74–498 mm,respectively,indicating a downward trend in precipitation.The central part of the state received the highest rainfall,while the eastern and western regions(spanning north to south)had significantly less.Over the decades of the third millennium,the average annual rainfall every five years was relatively low,showing a declining trend due to severe climate changes,generally ranging between 35 mm and 498 mm.The central regions consistently received more rainfall than the eastern and western outskirts.Arizona is currently experiencing a decrease in rainfall due to climate change,a situation that could deterio-rate further.This highlights the need to optimize the use of existing rainfall and explore alternative water sources. 展开更多
关键词 Spatial Analysis Climate Impact Precipitation Rates CRU Dataset GIS Arizona State USA
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A Comprehensive Review of Face Detection/Recognition Algorithms and Competitive Datasets to Optimize Machine Vision
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作者 Mahmood Ul Haq Muhammad Athar Javed Sethi +3 位作者 Sadique Ahmad Naveed Ahmad Muhammad Shahid Anwar Alpamis Kutlimuratov 《Computers, Materials & Continua》 2025年第7期1-24,共24页
Face recognition has emerged as one of the most prominent applications of image analysis and under-standing,gaining considerable attention in recent years.This growing interest is driven by two key factors:its extensi... Face recognition has emerged as one of the most prominent applications of image analysis and under-standing,gaining considerable attention in recent years.This growing interest is driven by two key factors:its extensive applications in law enforcement and the commercial domain,and the rapid advancement of practical technologies.Despite the significant advancements,modern recognition algorithms still struggle in real-world conditions such as varying lighting conditions,occlusion,and diverse facial postures.In such scenarios,human perception is still well above the capabilities of present technology.Using the systematic mapping study,this paper presents an in-depth review of face detection algorithms and face recognition algorithms,presenting a detailed survey of advancements made between 2015 and 2024.We analyze key methodologies,highlighting their strengths and restrictions in the application context.Additionally,we examine various datasets used for face detection/recognition datasets focusing on the task-specific applications,size,diversity,and complexity.By analyzing these algorithms and datasets,this survey works as a valuable resource for researchers,identifying the research gap in the field of face detection and recognition and outlining potential directions for future research. 展开更多
关键词 Face recognition algorithms face detection techniques face recognition/detection datasets
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The Development of Artificial Intelligence:Toward Consistency in the Logical Structures of Datasets,AI Models,Model Building,and Hardware?
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作者 Li Guo Jinghai Li 《Engineering》 2025年第7期13-17,共5页
The aim of this article is to explore potential directions for the development of artificial intelligence(AI).It points out that,while current AI can handle the statistical properties of complex systems,it has difficu... The aim of this article is to explore potential directions for the development of artificial intelligence(AI).It points out that,while current AI can handle the statistical properties of complex systems,it has difficulty effectively processing and fully representing their spatiotemporal complexity patterns.The article also discusses a potential path of AI development in the engineering domain.Based on the existing understanding of the principles of multilevel com-plexity,this article suggests that consistency among the logical structures of datasets,AI models,model-building software,and hardware will be an important AI development direction and is worthy of careful consideration. 展开更多
关键词 CONSISTENCY datasets model building ai models artificial intelligence ai explore potential directions HARDWARE artificial intelligence
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A critical evaluation of deep-learning based phylogenetic inference programs using simulated datasets
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作者 Yixiao Zhu Yonglin Li +2 位作者 Chuhao Li Xing-Xing Shen Xiaofan Zhou 《Journal of Genetics and Genomics》 2025年第5期714-717,共4页
Inferring phylogenetic trees from molecular sequences is a cornerstone of evolutionary biology.Many standard phylogenetic methods(such as maximum-likelihood[ML])rely on explicit models of sequence evolution and thus o... Inferring phylogenetic trees from molecular sequences is a cornerstone of evolutionary biology.Many standard phylogenetic methods(such as maximum-likelihood[ML])rely on explicit models of sequence evolution and thus often suffer from model misspecification or inadequacy.The on-rising deep learning(DL)techniques offer a powerful alternative.Deep learning employs multi-layered artificial neural networks to progressively transform input data into more abstract and complex representations.DL methods can autonomously uncover meaningful patterns from data,thereby bypassing potential biases introduced by predefined features(Franklin,2005;Murphy,2012).Recent efforts have aimed to apply deep neural networks(DNNs)to phylogenetics,with a growing number of applications in tree reconstruction(Suvorov et al.,2020;Zou et al.,2020;Nesterenko et al.,2022;Smith and Hahn,2023;Wang et al.,2023),substitution model selection(Abadi et al.,2020;Burgstaller-Muehlbacher et al.,2023),and diversification rate inference(Voznica et al.,2022;Lajaaiti et al.,2023;Lambert et al.,2023).In phylogenetic tree reconstruction,PhyDL(Zou et al.,2020)and Tree_learning(Suvorov et al.,2020)are two notable DNN-based programs designed to infer unrooted quartet trees directly from alignments of four amino acid(AA)and DNA sequences,respectively. 展开更多
关键词 phylogenetic inference explicit models sequence evolution deep learning deep learning dl techniques molecular sequences simulated datasets phylogenetic methods such evolutionary biologymany
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面向人脸视频防伪检测的大规模中文数据测评基准
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作者 贝毅君 娄恒瑞 +7 位作者 高克威 宋杰 王蕊 金苍宏 雷杰 宋明黎 胡秉德 冯尊磊 《中国图象图形学报》 北大核心 2026年第1期82-98,共17页
目的针对生成式人工智能(artificial intelligence generated content,AIGC)技术生成的高逼真伪造人脸视频对人类视觉感知的欺骗性问题,以及当前人脸防伪检测算法评估体系在中文数据层面有效性和应用性验证方面的空白,旨在构建面向中文... 目的针对生成式人工智能(artificial intelligence generated content,AIGC)技术生成的高逼真伪造人脸视频对人类视觉感知的欺骗性问题,以及当前人脸防伪检测算法评估体系在中文数据层面有效性和应用性验证方面的空白,旨在构建面向中文场景的量化评估基准以推动防伪检测技术迭代发展。方法提出面向大规模中文人脸伪造视频的CHN-DF(Chinese-deepfake)数据集,详细阐述数据采集、伪造样本生成及质量评估的全流程构建方法。通过多维度实验验证数据集复杂性,兼顾跨模态伪造技术覆盖、环境干扰因子完备性等复杂因素,并建立基于深度检测模型的系统性评测基准。结果发布全球首个包含434727样本的中文人脸视频防伪数据集,实验显示该数据集鉴别难度高,在16种包含SOTA(state-of-the-art)与主流防伪模型的测评中视觉与视听结合的准确率分别控制在85%与70%以下。构建的评测基准覆盖了视觉与听觉模态场景,在跨域泛化性测试中显示模型准确率性能波动平均幅度达19.6%,显著揭示现有算法的应用局限性。结论构建的中文防伪评测基准有效填补领域空白,通过系统性实验阐明数据集特性与算法性能的关联机制,提出针对模型鲁棒性增强、跨模态泛化能力提升等关键发展方向,为面向中文场景的量化评估以及人脸视频防伪技术的实际部署提供数据支撑与实践指导。CHN-DF数据集在线发布地址为:https://doi.org/10.57760/sciencedb.j00240.00067和https://github.com/HengruiLou/CHN-DF. 展开更多
关键词 深度伪造 人脸伪造视频 人脸防伪评测基准 中文数据集 多模态
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Impacts of random negative training datasets on machine learning-based geologic hazard susceptibility assessment
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作者 Hao Cheng Wei Hong +3 位作者 Zhen-kai Zhang Zeng-lin Hong Zi-yao Wang Yu-xuan Dong 《China Geology》 2025年第4期676-690,共15页
This study investigated the impacts of random negative training datasets(NTDs)on the uncertainty of machine learning models for geologic hazard susceptibility assessment of the Loess Plateau,northern Shaanxi Province,... This study investigated the impacts of random negative training datasets(NTDs)on the uncertainty of machine learning models for geologic hazard susceptibility assessment of the Loess Plateau,northern Shaanxi Province,China.Based on randomly generated 40 NTDs,the study developed models for the geologic hazard susceptibility assessment using the random forest algorithm and evaluated their performances using the area under the receiver operating characteristic curve(AUC).Specifically,the means and standard deviations of the AUC values from all models were then utilized to assess the overall spatial correlation between the conditioning factors and the susceptibility assessment,as well as the uncertainty introduced by the NTDs.A risk and return methodology was thus employed to quantify and mitigate the uncertainty,with log odds ratios used to characterize the susceptibility assessment levels.The risk and return values were calculated based on the standard deviations and means of the log odds ratios of various locations.After the mean log odds ratios were converted into probability values,the final susceptibility map was plotted,which accounts for the uncertainty induced by random NTDs.The results indicate that the AUC values of the models ranged from 0.810 to 0.963,with an average of 0.852 and a standard deviation of 0.035,indicating encouraging prediction effects and certain uncertainty.The risk and return analysis reveals that low-risk and high-return areas suggest lower standard deviations and higher means across multiple model-derived assessments.Overall,this study introduces a new framework for quantifying the uncertainty of multiple training and evaluation models,aimed at improving their robustness and reliability.Additionally,by identifying low-risk and high-return areas,resource allocation for geologic hazard prevention and control can be optimized,thus ensuring that limited resources are directed toward the most effective prevention and control measures. 展开更多
关键词 LANDSLIDES Debris flows Collapses Ground fissures Geologic hazard prevention and control ENGINEERING Geologic hazard susceptibility assessment Negative training dataset Average spatial correlation Random forest algorithm Risk and return analysis Geological survey engineering Loess Plateau area
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基于改进RT-DETR的有遮挡交通标志检测算法
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作者 于天河 杨壮壮 +2 位作者 胡金帅 常梦瑶 王文龙 《工程科学学报》 北大核心 2026年第2期393-408,共16页
针对交通标志检测中目标尺寸小、检测精度低等问题,尤其是在远距离拍摄、遮挡严重的情况下,传统检测算法往往难以准确识别交通标志.本文提出了一种基于改进RT-DETR的交通标志检测算法.首先,考虑到当前交通标志被遮挡情况下数据集的匮乏... 针对交通标志检测中目标尺寸小、检测精度低等问题,尤其是在远距离拍摄、遮挡严重的情况下,传统检测算法往往难以准确识别交通标志.本文提出了一种基于改进RT-DETR的交通标志检测算法.首先,考虑到当前交通标志被遮挡情况下数据集的匮乏,自建一个遮挡条件下的交通标志数据集.然后,在反向残差移动块中引入膨胀重参数块,构建了一个轻量级的复合膨胀残差块来替换原始主干提取网络中的BasicBlock,增强了模型的特征提取能力.最后,对RT-DETR模型的损失函数进行了优化,提出了DS-IoU联合损失函数加快收模型敛速度.实验结果表明,改进后的算法在自制数据集上的m AP为94.2%,相比于原始算法增加量为4.7%,在公开数据集TT100K和CCTSDB2021的m AP分别为92.8%和91.7%,相比于原始算法增加量分别为3.1%和2.4%,Params和GFLOPs相比于原始的算法分别降低了26.0%和12.5%.本文提出的改进方法极大地减少了计算量和参数数量,有效提升了遮挡情况下的交通标志的检测精度. 展开更多
关键词 交通标志检测 RT-DETR 遮挡数据集 轻量化 联合损失函数
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面向深度学习的川滇地区震例多源地球物理参数数据集及应用
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作者 余腾 向健斌 +2 位作者 朱益民 张丹丹 赵一霖 《地球科学》 北大核心 2026年第1期116-129,共14页
川滇地区新构造运动和地震活动强烈.近20年来积累了大量的地球物理观测资料,其中4.5级及以上地震由于其造成震损大而格外受到关注.深度学习技术基于数据驱动可以挖掘数据隐含特征,如震区地球物理参数特征及变化方式与中强震发生关联性,... 川滇地区新构造运动和地震活动强烈.近20年来积累了大量的地球物理观测资料,其中4.5级及以上地震由于其造成震损大而格外受到关注.深度学习技术基于数据驱动可以挖掘数据隐含特征,如震区地球物理参数特征及变化方式与中强震发生关联性,而以地震事件为单个样本的地震波检测数据集较丰富而地球物理背景数据集目前较为缺少.以川滇地区近20年的4.5级及以上的798个震例数据为基础,搜集了以震源为中心一定空间范围内与发震关联性较强的历史地震目录、重力、断层、地壳速度、地壳厚度、莫霍面深度、岩性和地下水等资料,通过计算、清洗和归一化等数据处理手段制作成了带标注的数据集.为了保证正、负例样本的平衡性,同样选取了与正例数量相等的不显著发震(3级及以下,与4.5级及以上地震能量相差悬殊)同区域的地球物理资料并制作了带标注的负例数据集;对数据集中正例、负例及数据组成进行了阐述,基于准确率、召回率等评估指标对数据集在4种经典的学习模型中使用效果进行分析,均可达到80%左右的准确率.最后通过在其他地区进行迁移学习方式验证了数据集的质量,并不低于数据集测试集的精度,这些表明构建的数据集具有良好的质量、适用性及泛化性,可为其他的深度学习地震学数据集的构建提供借鉴. 展开更多
关键词 川滇 地球物理参数 数据集 迁移学习 地震学
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基于均一化气温数据集的中国海拔依赖型增暖研究
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作者 胡宜昌 《气候变化研究进展》 北大核心 2026年第1期28-40,共13页
中国气温存在海拔依赖型增暖(EDW),但增暖趋势随海拔升高而增强(正EDW)或是减弱(负EDW),不同研究给出的结论并不完全一致。文中利用中国目前空间覆盖度较高的气象站逐日均一化气温数据集,研究1961—2021年及该期间多个子时期的气温变化... 中国气温存在海拔依赖型增暖(EDW),但增暖趋势随海拔升高而增强(正EDW)或是减弱(负EDW),不同研究给出的结论并不完全一致。文中利用中国目前空间覆盖度较高的气象站逐日均一化气温数据集,研究1961—2021年及该期间多个子时期的气温变化趋势与海拔高度的关系。结果表明,最低气温(Tmin)、最高气温(Tmax)、平均气温(Tmean)的年平均值均显示存在正EDW,青藏高原及其周边区域更显著;季节平均值的EDW差异明显,Tmax、Tmean以及1981年以来的Tmin春季存在显著的负EDW,其他季节平均Tmin、Tmax、Tmean绝大多数情况为显著的正EDW;月平均值的EDW表现出明显的月份差异,与Tmin、Tmean相比,Tmax对应的月份差异在各个时期都最显著,11月或12月正EDW达到最强,随后减弱,3月或4月负EDW达到最强,至6月转变为正EDW,6—10月正EDW强度相对稳定。考虑到纬度差异可能对EDW信号检测造成的影响,针对不同纬度带单独研究分析,所得结果与上述结论一致。中国气温的EDW特征与全球变暖背景下高海拔地区下垫面变化密切相关,EDW及其季节差异很可能是由积雪、植被覆盖变化等对应的辐射收支强迫造成的。 展开更多
关键词 气温 增温趋势 海拔依赖型增暖(EDW) 均一化数据集
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基于改进YOLOv8s的钢筋混凝土结构桥梁表观病害智能检测算法
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作者 廖维张 黄澍辰 +1 位作者 袁婉莹 秦铭辰 《科学技术与工程》 北大核心 2026年第4期1676-1687,共12页
为提升桥梁长期服役性能分析的智能化与自动化水平,并解决现有病害检测算法在复杂场景下的精度不足问题,提出一种改进YOLOv8s的桥梁表观病害智能检测算法YOLOv8s-RC。将大核可分离卷积注意力机制(large kernel separable convolutional ... 为提升桥梁长期服役性能分析的智能化与自动化水平,并解决现有病害检测算法在复杂场景下的精度不足问题,提出一种改进YOLOv8s的桥梁表观病害智能检测算法YOLOv8s-RC。将大核可分离卷积注意力机制(large kernel separable convolutional attention mechanism,LSKA)引入骨干网络的快速空间金字塔池化模块SPPF中,增强病害特征提取能力;采用双向特征金字塔(bidirectional feature pyramid network,BiFPN)的加权特征融合思想优化颈部网络的特征融,强化特征融合效能;将原有的CIoU损失函数替换为SIoU损失函数,提升预测框的定位精度。消融实验结果表明:在CODEBRIM数据集上,YOLOv8s-RC模型相较于原模型的精确率、召回率、F1分数和mAP@0.5指标分别提升了2.3%、1.7%、2.0%和1.6%。该算法针对小目标病害和弱特征病害表现出更强检测能力,且该模型参数量仅为12.2×10^(6),推理速度为107.5 FPS,也能满足算法部署于轻量级设备后的实时检测需求;在DACL10K数据集上的泛化性测试结果表明,相较于Faster-RCNN、SSD、YOLOv5s和YOLOv8s模型,YOLOv8s-RC模型在不同类型桥梁病害检测场景中表现出较好的泛化能力和预测准确性,为复杂环境下桥梁表观病害识别提供强有力的技术手段。 展开更多
关键词 桥梁工程 病害检测 小目标检测 YOLOv8s CODEBRIM数据集
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1981-2022年中国主要作物产量数据集的研制
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作者 高静 廖捷 刘媛媛 《中国农业气象》 2026年第3期456-472,共17页
基于1981-2012年全国653个国家级农业气象观测站纸质年报表及2013-2022年电子年报,选取连续开展小麦、水稻、玉米、油菜、棉花、大豆和花生7类主要作物产量观测的618个站点数据,通过作物名称及观测项目标准化、缺失数据补录、资料序列... 基于1981-2012年全国653个国家级农业气象观测站纸质年报表及2013-2022年电子年报,选取连续开展小麦、水稻、玉米、油菜、棉花、大豆和花生7类主要作物产量观测的618个站点数据,通过作物名称及观测项目标准化、缺失数据补录、资料序列统一、数据单位统一、元数据统一、质量控制和数据评估等处理流程,研制1981-2022年中国主要作物产量数据集,以期为农业气候变化相关研究提供基础数据支撑。结果表明:7类作物实际产量的5个观测项目数据的实际观测量占应有观测量(实有率)的91.0%以上,数据正确率>97.0%。产量因素20个观测项目的数据实有率除冬小麦越冬死亡率外,其他观测项目均>78.8%,所有观测项目正确率>97.0%。产量结构的60个观测项目数据实有率>88.6%,数据正确率>90.2%。对实有率较低的冬小麦越冬死亡率和玉米双穗率开展核查,部分零值数据被视为缺测值,通过数据订正使冬小麦越冬死亡率数据实有率从12.2%升至61.7%,玉米双穗率数据实有率从52.8%升至95.9%。该数据集为农业气候变化研究、生态与农业气象业务、防灾减灾策略制定、农业气候资源区划等提供统一标准与高质量的基础支撑数据,数据集研制过程中采用的综合质量控制方法,可为农业气象资料质量提升提供科学依据。 展开更多
关键词 作物数据集 实际产量 产量结构 产量因素 质量控制
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基于图神经网络实现多尺度特征联合学习的中文作文自动评分
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作者 文洪建 胡瑞娇 +4 位作者 吴保文 孙家兴 李环 张晴 刘杰 《计算机应用》 北大核心 2026年第2期378-385,共8页
现有基于预训练语言模型(PLM)的作文自动评分(AES)方法偏向于直接使用从PLM提取的全局语义特征表示作文的质量,却忽略了作文质量与更细粒度特征关联关系的问题。聚焦于中文AES研究,从多种文本角度分析和评估作文质量,提出利用图神经网络... 现有基于预训练语言模型(PLM)的作文自动评分(AES)方法偏向于直接使用从PLM提取的全局语义特征表示作文的质量,却忽略了作文质量与更细粒度特征关联关系的问题。聚焦于中文AES研究,从多种文本角度分析和评估作文质量,提出利用图神经网络(GNN)对作文的多尺度特征进行联合学习的中文AES方法。首先,利用GNN分别获取作文在句子级别和段落级别的篇章特征;然后,将这些篇章特征与作文的全局语义特征进行联合特征学习,实现对作文更精准的评分;最后,构建一个中文AES数据集,为中文AES研究提供数据基础。在所构建的数据集上的实验结果表明,所提方法在6个作文主题上的平均二次加权Kappa(QWK)系数相较于R2-BERT(Bidirectional Encoder Representations from Transformers model with Regression and Ranking)提升了1.1个百分点,验证了在AES任务中进行多尺度特征联合学习的有效性。同时,消融实验结果进一步表明了不同尺度的作文特征对评分效果的贡献。为了证明小模型在特定任务场景下的优越性,与当前流行的通用大语言模型GPT-3.5-turbo和DeepSeek-V3进行了对比。结果表明,使用所提方法的BERT(Bidirectional Encoder Representations from Transformers)模型在6个作文主题上的平均QWK比GPT-3.5-turbo和DeepSeek-V3分别高出了65.8和45.3个百分点,验证了大语言模型(LLMs)在面向领域的篇章级作文评分任务中,因缺乏大规模有监督微调数据而表现不佳的观点。 展开更多
关键词 中文作文自动评分 预训练语言模型 图神经网络 中文作文自动评分数据集 多特征学习
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基于声谱的低空无人机识别方法
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作者 张秀清 崔子硕 王晓君 《通信与信息技术》 2026年第2期130-133,共4页
针对低空无人机声检测易受背景噪声干扰的问题,提出了一种基于对数梅尔(Log-Mel)频谱图和残差网络(ResNet34)的无人机声谱识别方法。首先,汇总录制的音频和公开数据集,构建训练数据集和测试数据集。其次,对统一格式的数据集音频进行特... 针对低空无人机声检测易受背景噪声干扰的问题,提出了一种基于对数梅尔(Log-Mel)频谱图和残差网络(ResNet34)的无人机声谱识别方法。首先,汇总录制的音频和公开数据集,构建训练数据集和测试数据集。其次,对统一格式的数据集音频进行特征提取,构建Log-Mel特征图库,作为网络模型的输入。然后,在ResNet34模型上增加频带注意力机制模块(FBA),进一步提升噪声环境下的无人机音频检测能力。最后,对比模型在不同距离无人机音频测试集上的识别结果。实验结果表明,在背景噪声干扰情况下,所提方法对距离30米无人机音频识别的F1分数可达82.3%,较现有模型有显著提升,为无人机检测提供了一种新方法。 展开更多
关键词 无人机声谱识别 数据集构建 Log-Mel特征 注意力机制
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