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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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EFI-SATL:An Efficient Net and Self-Attention Based Biometric Recognition for Finger-Vein Using Deep Transfer Learning
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作者 Manjit Singh Sunil Kumar Singla 《Computer Modeling in Engineering & Sciences》 2025年第3期3003-3029,共27页
Deep Learning-based systems for Finger vein recognition have gained rising attention in recent years due to improved efficiency and enhanced security.The performance of existing CNN-based methods is limited by the pun... Deep Learning-based systems for Finger vein recognition have gained rising attention in recent years due to improved efficiency and enhanced security.The performance of existing CNN-based methods is limited by the puny generalization of learned features and deficiency of the finger vein image training data.Considering the concerns of existing methods,in this work,a simplified deep transfer learning-based framework for finger-vein recognition is developed using an EfficientNet model of deep learning with a self-attention mechanism.Data augmentation using various geometrical methods is employed to address the problem of training data shortage required for a deep learning model.The proposed model is tested using K-fold cross-validation on three publicly available datasets:HKPU,FVUSM,and SDUMLA.Also,the developed network is compared with other modern deep nets to check its effectiveness.In addition,a comparison of the proposed method with other existing Finger vein recognition(FVR)methods is also done.The experimental results exhibited superior recognition accuracy of the proposed method compared to other existing methods.In addition,the developed method proves to be more effective and less sophisticated at extracting robust features.The proposed EffAttenNet achieves an accuracy of 98.14%on HKPU,99.03%on FVUSM,and 99.50%on SDUMLA databases. 展开更多
关键词 Biometrics finger-vein recognition(FVR) deep net self-attention Efficient Nets transfer learning
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Spatiotemporal pattern analysis of wetland area change in Ruoergai County based on Google Earth Engine and deep learning
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作者 Xu Jian Chang Ruichun +1 位作者 Zhang Chi Tuo Wanquan 《地质学刊》 2025年第3期255-268,共14页
The article employs the wetlands of Ruoergai(i.e.,Zoige),Sichuan Province,as a case study to analyze changes over various time scales,utilizing Landsat data from 2004,2008,2012,2016,2020,and 2023.The study uses the GE... The article employs the wetlands of Ruoergai(i.e.,Zoige),Sichuan Province,as a case study to analyze changes over various time scales,utilizing Landsat data from 2004,2008,2012,2016,2020,and 2023.The study uses the GEE platform and a deep learning model,focusing on the long-term perspective.This analysis serves as a focal point for discussing sustainable development,offering ecological balance information and a realistic foundation.The paper systematically gathers remote sensing classification images resembling sample points on the GEE(Google Earth Engine)platform.Simultaneously,it develops a deep learning model for classifying land types in Ruoergai into six categories:river-wetland,lake-wetland,swamp-wetland,grassland,forest and shrubland.This classification is achieved by utilizing various bands of Landsat data as input features and assigning land cover as corresponding labels.A comparison of classification results in 2016 indicates that the approach integrating the GEE platform and the deep learning model enhances overall accuracy by 9%compared to the random forest method.Furthermore,the overall accuracy surpasses that of the support vector machine method by 16%,and the CART method by 23%.These results affirm that the combined GEE platform and deep learning model outperforms the random forest method in overall accuracy.The findings reveal a declining trend in the wetland area of Ruoergai from 2004 to 2012,with the area remaining relatively stable from 2012 to 2016.Subsequently,there is a significant increase from 2016 to 2023.These trends corroborate the positive outcomes of long-term environmental protection policies implemented by the Chinese government.Furthermore,they underscore the success and efforts exerted by both the government and society in the sustainable management of wetland ecosystems.This serves as an exemplary case for advancing the SDG 15.1 development goal. 展开更多
关键词 Google Earth Engine deep learning sustainable development wetland in Ruoergai
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The rise of deep learning:AI and engineering applications under the spotlight of the 2024 Nobel prize
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作者 Guangqi Chen Zheng Han 《Intelligent Geoengineering》 2025年第1期14-21,共8页
The rise of deep learning has brought about transformative advancements in both scientific research and engineering applications.The 2024 Nobel Prizes,particularly in Physics and Chemistry,highlighted the revolutionar... The rise of deep learning has brought about transformative advancements in both scientific research and engineering applications.The 2024 Nobel Prizes,particularly in Physics and Chemistry,highlighted the revolutionary impact of deep learning,with AlphaFold’s breakthrough in protein structure prediction exemplifying its potential.This review explores the historical evolution of deep learning,from its foundational theories in neural networks and connectionism to its modern applications in various fields.Focus is given to its use in geotechnical engineering,particularly in geological disaster prediction,tunnel safety monitoring,and structural design optimization.The integration of deep learning models such as Convolutional Neural Networks(CNNs),Recurrent Neural Networks(RNNs),and Transformers has enabled significant progress in analyzing complex,unstructured data,offering innovative solutions to longstanding engineering challenges.The review also examines the opportunities and challenges faced by the field,advocating for interdisciplinary collaboration and open data sharing to further unlock deep learning’s potential in advancing both scientific and engineering disciplines.As deep learning continues to evolve,it promises to drive further innovation,shaping the future of engineering practices and scientific discovery. 展开更多
关键词 Deep learning Artificial intelligence Historical evolution Geotechnical engineering Opportunities and challenges
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Real-time model updating and prediction of three-dimensional timevarying consolidation settlement using machine learning
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作者 Huaming Tian Yu Wang Danni Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第9期5954-5969,共16页
The development of digital twins for geotechnical structures necessitates the real-time updates of threedimensional(3D)virtual models(e.g.numerical finite element method(FEM)model)to accurately predict time-varying ge... The development of digital twins for geotechnical structures necessitates the real-time updates of threedimensional(3D)virtual models(e.g.numerical finite element method(FEM)model)to accurately predict time-varying geotechnical responses(e.g.consolidation settlement)in a 3D spatial domain.However,traditional 3D numerical model updating approaches are computationally prohibitive and therefore difficult to update the 3D responses in real time.To address these challenges,this study proposes a novel machine learning framework called sparse dictionary learning(T-3D-SDL)for real-time updating of time-varying 3D geotechnical responses.In T-3D-SDL,a concerned dataset(e.g.time-varying 3D settlement)is approximated as a linear superposition of dictionary atoms generated from 3D random FEM analyses.Field monitoring data are then used to identify non-trivial atoms and estimate their weights within a Bayesian framework for model updating and prediction.The proposed approach enables the real-time update of temporally varying settlements with a high 3D spatial resolution and quantified uncertainty as field monitoring data evolve.The proposed approach is illustrated using an embankment construction project.The results show that the proposed approach effectively improves settlement predictions along temporal and 3D spatial dimensions,with minimal latency(e.g.within minutes),as monitoring data appear.In addition,the proposed approach requires only a reasonably small number of 3D FEM model evaluations,avoids the use of widely adopted yet often criticized surrogate models,and effectively addresses the limitations(e.g.computational inefficiency)of existing 3D model updating approaches. 展开更多
关键词 Digital twin Three-dimensional(3D)finite element method(FEM) Time-varying 3D settlement Real-time model update Sparse dictionary learning(SDL)
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玻尔兹曼优化Q-learning的高速铁路越区切换控制算法 被引量:3
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作者 陈永 康婕 《控制理论与应用》 北大核心 2025年第4期688-694,共7页
针对5G-R高速铁路越区切换使用固定切换阈值,且忽略了同频干扰、乒乓切换等的影响,导致越区切换成功率低的问题,提出了一种玻尔兹曼优化Q-learning的越区切换控制算法.首先,设计了以列车位置–动作为索引的Q表,并综合考虑乒乓切换、误... 针对5G-R高速铁路越区切换使用固定切换阈值,且忽略了同频干扰、乒乓切换等的影响,导致越区切换成功率低的问题,提出了一种玻尔兹曼优化Q-learning的越区切换控制算法.首先,设计了以列车位置–动作为索引的Q表,并综合考虑乒乓切换、误码率等构建Q-learning算法回报函数;然后,提出玻尔兹曼搜索策略优化动作选择,以提高切换算法收敛性能;最后,综合考虑基站同频干扰的影响进行Q表更新,得到切换判决参数,从而控制切换执行.仿真结果表明:改进算法在不同运行速度和不同运行场景下,较传统算法能有效提高切换成功率,且满足无线通信服务质量QoS的要求. 展开更多
关键词 越区切换 5G-R Q-learning算法 玻尔兹曼优化策略
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改进自适应VMD和TLS-ESPRIT的风电系统次/超同步振荡参数辨识 被引量:2
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作者 李文博 钱伟荣 +3 位作者 李淑蓉 沙鹏程 邓军波 张冠军 《高电压技术》 北大核心 2025年第1期146-157,I0013-I0017,共17页
为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决... 为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决定分解模态数和带宽,结合最小二乘-旋转不变技术(total least square-estimating signal parameter via rotational invariance techniques,TLS-ESPRIT)对分解出的振荡分量进行参数辨识,无需另外使用降噪算法。通过复合信号测试法、PSCAD/EMTDC电磁暂态仿真法验证了所提方法的有效性。最后,将所提方法与改进Prony算法、MCEEMD法在不同噪声水平和振荡频率下进行对比,结果表明,所提方法能够有效地抑制原始信号的噪声干扰,对耦合的次/超同步振荡信号分解更加准确,参数辨识结果可靠性较高,对风电系统振荡溯源、改善系统阻尼具有一定的参考意义。 展开更多
关键词 SSSO 改进VMD 损失总熵 tlS-ESPRIT 模态混叠
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基于RFTL-1DNet的矿用挖掘机发动机故障诊断方法
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作者 顾清华 银璐阳子 +1 位作者 王丹 骆家乐 《有色金属(矿山部分)》 2025年第2期51-58,79,共9页
针对矿用挖掘机发动机故障数据集较少、诊断准确率低等问题,提出了一种基于一维卷积核、池化核的残差网络与迁移学习策略的故障诊断方法。通过随机森林(Random Forest,RF)分类器对初始数据集进行维度筛选,去除掉重要性低的特征以提高模... 针对矿用挖掘机发动机故障数据集较少、诊断准确率低等问题,提出了一种基于一维卷积核、池化核的残差网络与迁移学习策略的故障诊断方法。通过随机森林(Random Forest,RF)分类器对初始数据集进行维度筛选,去除掉重要性低的特征以提高模型的学习效率和分类精度,使用筛选后的10维数据集对一维残差网络(ResNet18_1D)模型进行预训练,并保留训练结果;添加随机噪声扩充数据集,将一维残差网络训练结束参数作为迁移学习(Transfer Learning,TL)初始参数,使用扩充后数据集进行五倍交叉验证训练,保存并输出训练模型;调用训练效果最佳的模型进行测试,并输出分类结果。利用河南某矿山挖掘机发动机故障数据集对上述RFTL-1DNet模型进行诊断实验,实验结果表明,所提出方法的故障诊断性能明显优于其他方法,对矿山挖掘机发动机状态诊断精度超过99%。该模型对发动机常见故障的高分类准确度可快速诊断出维修计划外的故障。研究结果为智慧矿山设备管理提出了新方法。 展开更多
关键词 矿用挖掘机发动机 故障诊断 深度学习 残差网络 迁移学习
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基于PCA-FCN混合模型的NaI(Tl)伽马能谱核素识别技术研究
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作者 刘鑫 赵日 +9 位作者 谭俊 王茂林 黄健 张静 梁润成 刘兆行 石忠焱 王佳 令狐仁静 刘立业 《辐射防护》 北大核心 2025年第4期327-336,共10页
NaI(Tl)探测器能量分辨率较差使得基于其获取的伽马能谱进行准确的核素识别较为困难,为提高识别准确率,综合已有研究方法和模型的优缺点,提出了PCA-FCN混合识别模型,并基于随机化策略通过实验测量和蒙特卡罗模拟构建了有较强通用性的γ... NaI(Tl)探测器能量分辨率较差使得基于其获取的伽马能谱进行准确的核素识别较为困难,为提高识别准确率,综合已有研究方法和模型的优缺点,提出了PCA-FCN混合识别模型,并基于随机化策略通过实验测量和蒙特卡罗模拟构建了有较强通用性的γ能谱数据集,利用数据集对模型进行训练并开展实验测量能谱验证。结果表明,PCA-FCN模型的核素识别A_(P)、F_(1)性能因子达到0.982 3和0.980 1,显著优于PCA模型、FCN模型和传统全能峰分析法,而且在不同能谱复杂度、不同能谱统计涨落下仍能保持识别准确性。该结论显示了PCA-FCN模型和随机化样本生成策略在未来放射性定量测量应用的潜力。 展开更多
关键词 NAI(tl)探测器 核素识别 伽马能谱 主成分分析 全连接网络
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基于TLS数据的落叶松–水曲柳混交林单木因子提取及树高模型构建研究 被引量:1
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作者 崔译今 贾炜玮 +2 位作者 王帆 郭昊天 李丹丹 《西南林业大学学报(自然科学)》 北大核心 2025年第2期142-150,共9页
以孟家岗林场1 hm^(2)落叶松水与曲柳混交林样地为研究对象,利用等株径级标准木法把林木分为优势木、平均木、被压木3个等级,然后以人工实测值作为参考值,分别分析利用TLS提取2种树种的3种等级木单木因子的精度,最后采用TLS数据提取的... 以孟家岗林场1 hm^(2)落叶松水与曲柳混交林样地为研究对象,利用等株径级标准木法把林木分为优势木、平均木、被压木3个等级,然后以人工实测值作为参考值,分别分析利用TLS提取2种树种的3种等级木单木因子的精度,最后采用TLS数据提取的单木因子构建树高模型。筛选出2种树种最优基础树高模型,并进一步评价和比较以林木分级为哑变量构建的树高模型。结果表明:针对本研究选取的水落混交林样地,点云数据与实测数据单木匹配结果中,落叶松匹配精度为92.79%,水曲柳为92.25%;2个树种的胸径提取精度达到97%以上,且胸径提取精度优势木>平均木>被压木,2个树种的树高提取精度达到95%以上,落叶松树高提取精度平均木>优势木>被压木;水曲柳树高提取精度优势木>平均木>被压木。使用TLS数据构建的基础树高模型中,拟合落叶松效果最好的是Logistic模型(R^(2)=0.783 0、RMSE=1.951 6),拟合水曲柳效果最好的是Gompertz模型(R^(2)=0.724 8、RMSE=1.953 6),因此以Logistic模型、Gompertz模型分别为2个树种基于TLS数据构建的最优基础模型,最后2个树种采用以林木分级为哑变量构建的模型R^(2)分别为0.790 7、0.731 2。TLS技术对水落混交林样地单木匹配率很高,单木因子提取精度较好,基于TLS数据所构建的以林木分级为哑变量的模型,在预测树木高度和胸径的生长差异方面表现优于基础模型,具有更好的预测精度和适应性,可以为该地区水落混交林的林业经营提供参考。 展开更多
关键词 落叶松 水曲柳 混交林 地基激光雷达 树高 哑变量模型
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大型地下洞室的TLS点云变形监测研究
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作者 王浩帆 李彪 +3 位作者 李涛 肖培伟 钱洪建 徐奴文 《测绘通报》 北大核心 2025年第8期76-82,共7页
大型地下洞室中变形控制不及时可能会对人员安全和工程进度构成严重威胁,对地下洞室进行变形监测对于预防工程灾害具有重要意义。为解决大型地下洞室工程中变形监测效率低且信息不全面的问题,本文提出了一种基于TLS点云的变形观测技术... 大型地下洞室中变形控制不及时可能会对人员安全和工程进度构成严重威胁,对地下洞室进行变形监测对于预防工程灾害具有重要意义。为解决大型地下洞室工程中变形监测效率低且信息不全面的问题,本文提出了一种基于TLS点云的变形观测技术。该技术包括结合RANSAC Shape Detection算法与曲面变化量的半自动点云降噪处理,以及基于M3C2算法的洞室表面变形计算,实现了大型地下洞室变形全面、高效的监测。应用该技术对旭龙电站主厂房典型区域支护变形进行监测,发现在施工频繁阶段Yc0+140—Yc0+170区间,下游侧拱座存在明显变形条带,且该结果与现场传统变形监测结果一致。观测结果为大型地下洞室变形控制提供了更为全面的三维变形信息,并提高了变形监测的效率。 展开更多
关键词 大型地下洞室 旭龙水电站 tlS点云 表面变形 点云降噪
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基于SWT和ResNet50-TL-S模型的小样本齿轮箱故障诊断模型
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作者 许家瑞 陈焰 《机电工程》 北大核心 2025年第8期1458-1468,共11页
在传统齿轮箱故障诊断过程中,因故障样本稀缺会导致模型的故障诊断精度降低。针对这一问题,提出了一种基于同步压缩小波变换(SWT)和ResNet50-TL-S模型的小样本齿轮箱故障诊断方法(模型)。首先,使用小波阈值去噪算法对采集到的齿轮箱振... 在传统齿轮箱故障诊断过程中,因故障样本稀缺会导致模型的故障诊断精度降低。针对这一问题,提出了一种基于同步压缩小波变换(SWT)和ResNet50-TL-S模型的小样本齿轮箱故障诊断方法(模型)。首先,使用小波阈值去噪算法对采集到的齿轮箱振动信号进行了阈值化去噪处理,消除了背景噪声;然后,使用同步压缩小波变换算法,对去噪后的振动信号进行了时频分析和时频变换,将一维去噪信号转变为二维时频图,用于构建故障诊断模型的训练样本;接着,对预训练ResNet50模型进行了微调,实现了迁移学习(TL)目的,并对迁移学习模型进行了轻量化改进,同时在模型内部嵌入了多头注意力机制,用于改善模型对不同特征权重的分配;最后,使用2组齿轮副数据和2组轴承数据,对基于SWT和ResNet50-TL-S模型的小样本齿轮箱故障诊断方法的有效性进行了验证。研究结果表明:基于SWT和ResNet50-TL-S模型的小样本齿轮箱故障诊断方法在无负荷工况下的单齿轮副故障诊断中,模型分类精度高达99.45%,模型训练时间为644 s;在齿轮副和轴承多重故障诊断中,模型分类精度为99.59%,模型训练时间为643 s;在有负荷工况的轴承和齿轮副多重故障诊断中,模型分类精度为98.12%,模型训练时间为646 s。这表明基于SWT和ResNet50-TL-S模型的齿轮箱故障诊断方法具备较高的齿轮箱故障诊断精度和较短的模型训练时间。 展开更多
关键词 机械传动 小波阈值去噪 同步压缩小波变换 ResNet50模型 轻量化改进 多头注意力机制 迁移学习模型
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基于特征选择与JITL-Optuna-KPLS的烧结矿成品率预测
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作者 陈许玲 张羽军 +3 位作者 黄晓贤 冯振湘 彭梓塘 范晓慧 《钢铁研究学报》 北大核心 2025年第10期1273-1280,共8页
烧结矿成品率是烧结生产的重要技术经济指标,对其进行预测可以为生产操作提供重要参考。针对烧结过程高维度、时变性和非线性等特点,提出了一种基于特征选择与JITL-Optuna-KPLS的烧结矿成品率预测模型。首先利用工艺知识和递归特征消除... 烧结矿成品率是烧结生产的重要技术经济指标,对其进行预测可以为生产操作提供重要参考。针对烧结过程高维度、时变性和非线性等特点,提出了一种基于特征选择与JITL-Optuna-KPLS的烧结矿成品率预测模型。首先利用工艺知识和递归特征消除法进行特征选择,得到最佳烧结矿成品率预测特征子集;然后提出一种采用复合相似性度量的即时学习方法,从历史数据样本中抽取小规模预测样本,使用Optuna算法优化超参数后的核偏最小二乘方法建立局部模型,实现对烧结矿成品率的预测。试验结果表明:所提出模型烧结矿成品率预测的均方误差为0.18,决定系数为0.98,平均相对误差为0.13%,能够满足实际生产的预测精度要求。 展开更多
关键词 烧结矿成品率 核偏最小二乘法 即时学习 Optuna 特征选择
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Early identification of stroke through deep learning with multi-modal human speech and movement data 被引量:4
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作者 Zijun Ou Haitao Wang +9 位作者 Bin Zhang Haobang Liang Bei Hu Longlong Ren Yanjuan Liu Yuhu Zhang Chengbo Dai Hejun Wu Weifeng Li Xin Li 《Neural Regeneration Research》 SCIE CAS 2025年第1期234-241,共8页
Early identification and treatment of stroke can greatly improve patient outcomes and quality of life.Although clinical tests such as the Cincinnati Pre-hospital Stroke Scale(CPSS)and the Face Arm Speech Test(FAST)are... Early identification and treatment of stroke can greatly improve patient outcomes and quality of life.Although clinical tests such as the Cincinnati Pre-hospital Stroke Scale(CPSS)and the Face Arm Speech Test(FAST)are commonly used for stroke screening,accurate administration is dependent on specialized training.In this study,we proposed a novel multimodal deep learning approach,based on the FAST,for assessing suspected stroke patients exhibiting symptoms such as limb weakness,facial paresis,and speech disorders in acute settings.We collected a dataset comprising videos and audio recordings of emergency room patients performing designated limb movements,facial expressions,and speech tests based on the FAST.We compared the constructed deep learning model,which was designed to process multi-modal datasets,with six prior models that achieved good action classification performance,including the I3D,SlowFast,X3D,TPN,TimeSformer,and MViT.We found that the findings of our deep learning model had a higher clinical value compared with the other approaches.Moreover,the multi-modal model outperformed its single-module variants,highlighting the benefit of utilizing multiple types of patient data,such as action videos and speech audio.These results indicate that a multi-modal deep learning model combined with the FAST could greatly improve the accuracy and sensitivity of early stroke identification of stroke,thus providing a practical and powerful tool for assessing stroke patients in an emergency clinical setting. 展开更多
关键词 artificial intelligence deep learning DIAGNOSIS early detection FAST SCREENING STROKE
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基于天然本底^(40)K、^(208)Tl和^(214)Bi的温漂修正方法研究
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作者 范浩 周伟 +2 位作者 张林 慕志洋 柯嘉旭 《核电子学与探测技术》 北大核心 2025年第2期180-188,共9页
目前NaI(Tl)γ谱仪在国际和国内被普遍用来实时监测环境中的放射性含量,但是在长期连续测量后,NaI(Tl)γ谱仪测得的伽马能谱在温度变化时会发生温漂,直接干扰了合成伽马能谱解析结果的准确性。通过使用NaI(Tl)γ谱仪进行以5℃为温度变... 目前NaI(Tl)γ谱仪在国际和国内被普遍用来实时监测环境中的放射性含量,但是在长期连续测量后,NaI(Tl)γ谱仪测得的伽马能谱在温度变化时会发生温漂,直接干扰了合成伽马能谱解析结果的准确性。通过使用NaI(Tl)γ谱仪进行以5℃为温度变化步长的测量实验,研究-5~50℃温度范围内测得的伽马能谱数据随温度变化而产生的漂移规律,并将-5~50℃温度范围内的漂移峰位道址表示成温度的二次函数关系,设计了一种基于天然本底^(40)K(1461 keV)、^(208)Tl(2614 keV)和^(214)Bi(1120 keV)的温漂修正方法。经验证,在总测量道址数为2048道的情况下,修正后的不同温度下的峰位道址与参考峰位道址的最大间隔不超过±1道,能够满足NaI(Tl)γ谱仪长期连续测量伽马能谱时的温漂修正要求。 展开更多
关键词 NaI(tl)γ谱仪 伽马能谱 温漂修正 峰位道址
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The Internet of Things under Federated Learning:A Review of the Latest Advances and Applications 被引量:1
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作者 Jinlong Wang Zhenyu Liu +2 位作者 Xingtao Yang Min Li Zhihan Lyu 《Computers, Materials & Continua》 SCIE EI 2025年第1期1-39,共39页
With the rapid development of artificial intelligence,the Internet of Things(IoT)can deploy various machine learning algorithms for network and application management.In the IoT environment,many sensors and devices ge... With the rapid development of artificial intelligence,the Internet of Things(IoT)can deploy various machine learning algorithms for network and application management.In the IoT environment,many sensors and devices generatemassive data,but data security and privacy protection have become a serious challenge.Federated learning(FL)can achieve many intelligent IoT applications by training models on local devices and allowing AI training on distributed IoT devices without data sharing.This review aims to deeply explore the combination of FL and the IoT,and analyze the application of federated learning in the IoT from the aspects of security and privacy protection.In this paper,we first describe the potential advantages of FL and the challenges faced by current IoT systems in the fields of network burden and privacy security.Next,we focus on exploring and analyzing the advantages of the combination of FL on the Internet,including privacy security,attack detection,efficient communication of the IoT,and enhanced learning quality.We also list various application scenarios of FL on the IoT.Finally,we propose several open research challenges and possible solutions. 展开更多
关键词 Federated learning Internet of Things SENSORS machine learning privacy security
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TLERAD: Transfer Learning for Enhanced Ransomware Attack Detection
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作者 Isha Sood Varsha Sharm 《Computers, Materials & Continua》 SCIE EI 2024年第11期2791-2818,共28页
Ransomware has emerged as a critical cybersecurity threat,characterized by its ability to encrypt user data or lock devices,demanding ransom for their release.Traditional ransomware detection methods face limitations ... Ransomware has emerged as a critical cybersecurity threat,characterized by its ability to encrypt user data or lock devices,demanding ransom for their release.Traditional ransomware detection methods face limitations due to their assumption of similar data distributions between training and testing phases,rendering them less effective against evolving ransomware families.This paper introduces TLERAD(Transfer Learning for Enhanced Ransomware Attack Detection),a novel approach that leverages unsupervised transfer learning and co-clustering techniques to bridge the gap between source and target domains,enabling robust detection of both known and unknown ransomware variants.The proposed method achieves high detection accuracy,with an AUC of 0.98 for known ransomware and 0.93 for unknown ransomware,significantly outperforming baseline methods.Comprehensive experiments demonstrate TLERAD’s effectiveness in real-world scenarios,highlighting its adapt-ability to the rapidly evolving ransomware landscape.The paper also discusses future directions for enhancing TLERAD,including real-time adaptation,integration with lightweight and post-quantum cryptography,and the incorporation of explainable AI techniques. 展开更多
关键词 Ransomware detection transfer learning unsupervised learning CO-CLUSTERING CYBERSECURITY machine learning lightweight cryptography post-quantum cryptography explainable AI tlERAD
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基于MDP和Q-learning的绿色移动边缘计算任务卸载策略
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作者 赵宏伟 吕盛凱 +2 位作者 庞芷茜 马子涵 李雨 《河南理工大学学报(自然科学版)》 北大核心 2025年第5期9-16,共8页
目的为了在汽车、空调等制造类工业互联网企业中实现碳中和,利用边缘计算任务卸载技术处理生产设备的任务卸载问题,以减少服务器的中心负载,减少数据中心的能源消耗和碳排放。方法提出一种基于马尔可夫决策过程(Markov decision process... 目的为了在汽车、空调等制造类工业互联网企业中实现碳中和,利用边缘计算任务卸载技术处理生产设备的任务卸载问题,以减少服务器的中心负载,减少数据中心的能源消耗和碳排放。方法提出一种基于马尔可夫决策过程(Markov decision process,MDP)和Q-learning的绿色边缘计算任务卸载策略,该策略考虑了计算频率、传输功率、碳排放等约束,基于云边端协同计算模型,将碳排放优化问题转化为混合整数线性规划模型,通过MDP和Q-learning求解模型,并对比随机分配算法、Q-learning算法、SARSA(state action reward state action)算法的收敛性能、碳排放与总时延。结果与已有的计算卸载策略相比,新策略对应的任务调度算法收敛比SARSA算法、Q-learning算法分别提高了5%,2%,收敛性更好;系统碳排放成本比Q-learning算法、SARSA算法分别减少了8%,22%;考虑终端数量多少,新策略比Q-learning算法、SARSA算法终端数量分别减少了6%,7%;系统总计算时延上,新策略明显低于其他算法,比随机分配算法、Q-learning算法、SARSA算法分别减少了27%,14%,22%。结论该策略能够合理优化卸载计算任务和资源分配,权衡时延、能耗,减少系统碳排放量。 展开更多
关键词 碳排放 边缘计算 强化学习 马尔可夫决策过程 任务卸载
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SensFL:Privacy-Preserving Vertical Federated Learning with Sensitive Regularization 被引量:1
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作者 Chongzhen Zhang Zhichen Liu +4 位作者 Xiangrui Xu Fuqiang Hu Jiao Dai Baigen Cai Wei Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期385-404,共20页
In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data silos.Vertical Federated Learning(VFL)has emerged as a promising approach... In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data silos.Vertical Federated Learning(VFL)has emerged as a promising approach to facilitate such collaboration,allowing diverse entities to collectively enhance machine learning models without the need to share sensitive training data.However,existing works have highlighted VFL’s susceptibility to privacy inference attacks,where an honest but curious server could potentially reconstruct a client’s raw data from embeddings uploaded by the client.This vulnerability poses a significant threat to VFL-based intelligent railway transportation systems.In this paper,we introduce SensFL,a novel privacy-enhancing method to against privacy inference attacks in VFL.Specifically,SensFL integrates regularization of the sensitivity of embeddings to the original data into the model training process,effectively limiting the information contained in shared embeddings.By reducing the sensitivity of embeddings to the original data,SensFL can effectively resist reverse privacy attacks and prevent the reconstruction of the original data from the embeddings.Extensive experiments were conducted on four distinct datasets and three different models to demonstrate the efficacy of SensFL.Experiment results show that SensFL can effectively mitigate privacy inference attacks while maintaining the accuracy of the primary learning task.These results underscore SensFL’s potential to advance privacy protection technologies within VFL-based intelligent railway systems,addressing critical security concerns in collaborative learning environments. 展开更多
关键词 Vertical federated learning PRIVACY DEFENSES
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小龙虾壳生物炭联合黄曲霉TL-F3对Cd(Ⅱ)和Zn(Ⅱ)吸附特性及机理研究
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作者 齐茜然 盛花泽宇 +6 位作者 陆昕彤 高雨慈 张旋旋 陈海燕 叶文玲 樊霆 马冬杰 《环境化学》 北大核心 2025年第11期4509-4522,共14页
本研究制备小龙虾壳生物炭(CBC)与黄曲霉TL-F3(Aspergillus flavus TL-F3)采用自固定的方式联合,通过批量实验探究pH、时间和重金属初始浓度对小龙虾壳生物炭联合黄曲霉TL-F3真菌颗粒(biochar combined Aspergillus flavus TL-F3 fungal... 本研究制备小龙虾壳生物炭(CBC)与黄曲霉TL-F3(Aspergillus flavus TL-F3)采用自固定的方式联合,通过批量实验探究pH、时间和重金属初始浓度对小龙虾壳生物炭联合黄曲霉TL-F3真菌颗粒(biochar combined Aspergillus flavus TL-F3 fungal pellet,BAP)对单一及复合重金属体系中吸附Cd(Ⅱ)和Zn(Ⅱ)的影响;并采用吸附等温线、吸附动力学及表征分析进行吸附机理探讨.单一体系pH 8.0时BAP对Cd(Ⅱ)和Zn(Ⅱ)最佳吸附率分别为79.9%、67.8%,复合体系中pH 7.0时吸附率分别为48.0%、70.8%.BAP吸附过程符合拟二级动力学模型和Langmuir等温模型,生物吸附过程为单层吸附,主要被化学吸附控制,对Cd(Ⅱ)和Zn(Ⅱ)最大吸附率可达95.1%和73.0%.BAP吸附后将部分重金属留在细胞内部;O—H、—C—H、C=O和N—H官能团参与反应,BAP表面CaCO3含量减少50%以上,研究表明BAP吸附机制为静电吸附、表面络合、π键、氢键作用.因此,BAP可作为高效处理镉、锌复合污染水体的修复材料. 展开更多
关键词 小龙虾壳生物炭 黄曲霉 tl-F3 吸附特性 吸附机理
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