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Transforming growth factor-β and toll-like receptor-4 polymorphisms are not associated with fibrosis in haemochromatosis 被引量:1
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作者 Marnie J Wood Lawrie W Powell +2 位作者 Jeannette L Dixon V Nathan Subramaniam Grant A Ramm 《World Journal of Gastroenterology》 SCIE CAS 2013年第48期9366-9376,共11页
AIM:To investigate the role of genetic polymorphisms in the progression of hepatic fibrosis in hereditary haemochromatosis.METHODS:A cohort of 245 well-characterised C282Y homozygous patients with haemochromatosis was... AIM:To investigate the role of genetic polymorphisms in the progression of hepatic fibrosis in hereditary haemochromatosis.METHODS:A cohort of 245 well-characterised C282Y homozygous patients with haemochromatosis was studied,with all subjects having liver biopsy data and DNA available for testing.This study assessed the association of eight single nucleotide polymorphisms(SNPs)in a total of six genes including toll-like receptor 4(TLR4),transforming growth factor-beta(TGF-β),oxoguanine DNA glycosylase,monocyte chemoattractant protein 1,chemokine C-C motif receptor 2 and interleukin-10 with liver disease severity.Genotyping was performed using high resolution melt analysis and sequencing.The results were analysed in relation to the stage of hepatic fibrosis in multivariate analysis incorporating other cofactors including alcohol consumption and hepatic iron concentration.RESULTS:There were significant associations between the cofactors of male gender(P=0.0001),increasing age(P=0.006),alcohol consumption(P=0.0001),steatosis(P=0.03),hepatic iron concentration(P<0.0001)and the presence of hepatic fibrosis.Of the candidate gene polymorphisms studied,none showed a significant association with hepatic fibrosis in univariate or multivariate analysis incorporating cofactors.We also specifically studied patients with hepatic iron loading above threshold levels for cirrhosis and compared the genetic polymorphisms between those with no fibrosis vs cirrhosis however there was no significant effect from any of the candidate genes studied.Importantly,in this large,well characterised cohort of patients there was no association between SNPs for TGF-βor TLR4and the presence of fibrosis,cirrhosis or increasing fibrosis stage in multivariate analysis.CONCLUSION:In our large,well characterised group of haemochromatosis subjects we did not demonstrate any relationship between candidate gene polymorphisms and hepatic fibrosis or cirrhosis. 展开更多
关键词 HAEMOCHROMATOSIS Genetic polymorphism Liver FIBROSIS TOLL-LIKE receptor 4 Interleukin 10 Monocyte CHEMOATTRACTANT protein 1 Chemokine(C-C motif) ligand 2 transforming growth factor beta 8-oxoguanine DNA GLYCOSYLASE
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In-situ observations on interphase boundary migration and grain growth during α/γ phase transformation in iron-4.2%Cr alloy
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作者 渡边忠雄 OBARA Kouichi TSUREKAWA Sadahiro 《材料与冶金学报》 CAS 2005年第2期91-91,共1页
In-situ observations on α/γ phase transformation were made to study the effects of grain boundary microstructures on the formation of a new phase and the migration of α/γ interphase boundary in an iron4. 2%Cr allo... In-situ observations on α/γ phase transformation were made to study the effects of grain boundary microstructures on the formation of a new phase and the migration of α/γ interphase boundary in an iron4. 2%Cr alloy. It was found that triple junctions with more random boundaries could be the primary nucleation sites for a new phase, while triple junctions with low angle or low ∑ coincidence boundaries did not play any role as preferential sites. The migration of α/γ interphase boundary during heating over the transformation temperature range showed the two stage behaviour characterized by a stage with a migration velocity of 0. 33-0. 75 mm/s and secondly by a stage with 3. 7-7. 6 mm/s. It was also found that abnormal grain growth and a high density of ∑3 coincidence boundaries could occur in a phase with bcc structure after cycling of α/γ phase transformation. A new mechanism of nucleation and growth of a new phase in α/γ phase transformation is proposed on the basis of roles of plane-matching interphase boundaries, as previously discussed on the origin of anisotropy of grain growth due to the migration of {110} plane-matching boundaries in Fe-3z%Si alloy. The most recent theoretical work on the distribution of plane-matching boundaries in solids with different crystal structures was found to be useful for the understanding of nucleation and growth during α/γ phase transformation. 展开更多
关键词 In-situ phase velocity stage effects crystal with random origin the range after new was more play over high MOST for The to DID BCC It be
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Advancing Breast Cancer Molecular Subtyping:A Comparative Study of Convolutional Neural Networks and Vision Transformers on Mammograms
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作者 Chee Chin Lim Hui Wen Tiu +2 位作者 Qi Wei Oung Chiew Chea Lau Xiao Jian Tan 《Computers, Materials & Continua》 2026年第3期1287-1308,共22页
critical for guiding treatment and improving patient outcomes.Traditional molecular subtyping via immuno-histochemistry(IHC)test is invasive,time-consuming,and may not fully represent tumor heterogeneity.This study pr... critical for guiding treatment and improving patient outcomes.Traditional molecular subtyping via immuno-histochemistry(IHC)test is invasive,time-consuming,and may not fully represent tumor heterogeneity.This study proposes a non-invasive approach using digital mammography images and deep learning algorithm for classifying breast cancer molecular subtypes.Four pretrained models,including two Convolutional Neural Networks(MobileNet_V3_Large and VGG-16)and two Vision Transformers(ViT_B_16 and ViT_Base_Patch16_Clip_224)were fine-tuned to classify images into HER2-enriched,Luminal,Normal-like,and Triple Negative subtypes.Hyperparameter tuning,including learning rate adjustment and layer freezing strategies,was applied to optimize performance.Among the evaluated models,ViT_Base_Patch16_Clip_224 achieved the highest test accuracy(94.44%),with equally high precision,recall,and F1-score of 0.94,demonstrating excellent generalization.MobileNet_V3_Large achieved the same accuracy but showed less training stability.In contrast,VGG-16 recorded the lowest performance,indicating a limitation in its generalizability for this classification task.The study also highlighted the superior performance of the Vision Transformer models over CNNs,particularly due to their ability to capture global contextual features and the benefit of CLIP-based pretraining in ViT_Base_Patch16_Clip_224.To enhance clinical applicability,a graphical user interface(GUI)named“BCMS Dx”was developed for streamlined subtype prediction.Deep learning applied to mammography has proven effective for accurate and non-invasive molecular subtyping.The proposed Vision Transformer-based model and supporting GUI offer a promising direction for augmenting diagnostic workflows,minimizing the need for invasive procedures,and advancing personalized breast cancer management. 展开更多
关键词 Artificial intelligence breast cancer classification convolutional neural network deep learning hyperparameter tuning MAMMOGRAPHY medical imaging molecular subtypes vision transformer
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基于CNN-Transformer架构的电磁传播损耗预测算法
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作者 万勇 李骏杰 +1 位作者 孙伟峰 戴永寿 《现代电子技术》 北大核心 2026年第6期43-48,共6页
为了解决传统经验传播损耗模型预测精度不足的问题,提出一种基于CNN-Transformer架构的电磁传播损耗预测算法,通过构建回归模型进行精准的传播损耗预测。通过斯皮尔曼系数法提取有效特征,利用CNN提取与传播损耗预测高度相关的浅层特征,... 为了解决传统经验传播损耗模型预测精度不足的问题,提出一种基于CNN-Transformer架构的电磁传播损耗预测算法,通过构建回归模型进行精准的传播损耗预测。通过斯皮尔曼系数法提取有效特征,利用CNN提取与传播损耗预测高度相关的浅层特征,将从卫星图像中获取的传播路径上地物特征序列进行位置编码,增强对传播路径中不同地物特征顺序对传播损耗影响的理解。最后将CNN提取的浅层特征与位置编码后的地物特征输入到Transformer模型,通过多头自注意力机制捕捉特征间的全局关联性,从而有效校正传播损耗的预测结果。实验结果表明,所提出的CNN-Transformer方法显著降低了传播损耗预测的均方根误差(RMSE),达到了3.3745 dB,同时保持了0.8956的较高确定性系数(R^(2))。所提的电磁传播损耗预测算法为无线通信传播特性研究领域提供了参考,具有一定的应用价值。 展开更多
关键词 transformER CNN
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多尺度非对称注意力遥感去雾Transformer
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作者 王旭阳 梁宇航 《广西师范大学学报(自然科学版)》 北大核心 2026年第2期77-89,共13页
雾霾干扰会导致遥感图像结构模糊、细节丢失,严重影响下游视觉任务的准确性。为此,本文提出一种异构增强的遥感图像去雾网络,从空间结构建模与频率信息整合2个层面提升特征恢复能力。具体而言,设计多尺度非对称注意力Transformer模块,... 雾霾干扰会导致遥感图像结构模糊、细节丢失,严重影响下游视觉任务的准确性。为此,本文提出一种异构增强的遥感图像去雾网络,从空间结构建模与频率信息整合2个层面提升特征恢复能力。具体而言,设计多尺度非对称注意力Transformer模块,引入方向感知机制以增强模糊边缘与纹理细节的建模;同时构建基于小波变换高低频自适应增强模块,使用Haar小波分解分离频域信息,分别通过高频与低频子模块强化边缘轮廓与结构表达。2个模块分别嵌入特征提取与融合阶段,协同缓解传统方法方向性建模不足与高频特征易丢失等问题。在保持低计算开销的前提下,本文方法在HAZE1K与RICE数据集上的平均PSNR/SSIM性能分别达到24.9936/0.9099与33.1802/0.8942,在细节恢复方面表现出显著优势。 展开更多
关键词 transformER
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基于PyConv-Transformer的锂离子电池剩余寿命预测
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作者 吴忠强 吴江浩 《计量学报》 北大核心 2026年第1期102-110,共9页
锂离子电池的剩余使用寿命(RUL)是电池健康管理的重要参数。电池在实际使用过程中会出现容量再生现象,而且在电池数据采集过程中,通常难以避免噪声干扰,影响数据质量。针对以上问题提出一种基于Transformer结合金字塔卷积网络的电池RUL... 锂离子电池的剩余使用寿命(RUL)是电池健康管理的重要参数。电池在实际使用过程中会出现容量再生现象,而且在电池数据采集过程中,通常难以避免噪声干扰,影响数据质量。针对以上问题提出一种基于Transformer结合金字塔卷积网络的电池RUL预测模型,选取容量作为健康因子,利用金字塔卷积网络中不同大小的卷积核提取容量序列的特征信息,利用Transformer中的多头注意力机制进一步学习序列的时序特征。采用加权Huber损失函数,提高模型的鲁棒性;采用Dropout技术,提高模型的泛化能力,防止训练过程中出现过拟合。将所提预测模型在NASA和CALCE数据集上实验,并与其他模型比较。实验结果表明,所提模型的预测精度更高,在NASA和CALCE数据集上的相对误差分别为0.008 6、0.019 3;平均绝对误差分别为0.011 5、0.012 6;均方根误差分别为0.017 3、0.018 9。 展开更多
关键词 使寿 transformER Huber DROPOUT
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The involvement of p38 MAPK in transforming growth factor β1-induced apoptosis in murine hepatocytes 被引量:15
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作者 LiaoJH ChenJS 《Cell Research》 SCIE CAS CSCD 2001年第2期89-94,共6页
We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly ... We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis. 展开更多
关键词 Animals Apoptosis Cells Cultured DNA Fragmentation Enzyme Inhibitors Gene Expression Regulation Enzymologic Genes Reporter Genetic Vectors HEPATOCYTES IMIDAZOLES MAP Kinase Signaling System Mice Mitogen-Activated Protein Kinases Mutation Phosphorylation Plasminogen Activator Inhibitor 1 PYRIDINES Research Support Non-U.S. Gov't TRANSFECTION transforming Growth Factor beta p38 Mitogen-Activated Protein Kinases
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层级特征融合Transformer的图像分类算法
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作者 段士玺 王博 《电子科技》 2026年第2期72-78,共7页
针对传统ViT(Vision Transformer)模型难以完成图像多层级分类问题,文中提出了基于ViT的图像分类模型层级特征融合视觉Transformer(Hierarchical Feature Fusion Vision Transformer,HICViT)。输入数据经过ViT提取模块生成多个不同层级... 针对传统ViT(Vision Transformer)模型难以完成图像多层级分类问题,文中提出了基于ViT的图像分类模型层级特征融合视觉Transformer(Hierarchical Feature Fusion Vision Transformer,HICViT)。输入数据经过ViT提取模块生成多个不同层级的特征图,每个特征图包含不同层次的抽象特征表示。基于层级标签将ViT提取的特征映射为多级特征,运用层级特征融合策略整合不同层级信息,有效增强模型的分类性能。在CIFRA-10、CIFRA-100和CUB-200-2011这3个数据集将所提模型与多种先进深度学习模型进行对比和分析。在CIFRA-10数据集,所提方法在第1层级、第2层级和第3层级的分类精度分别为99.70%、98.80%和97.80%。在CIFRA-100数据集,所提方法在第1层级、第2层级和第3层级的分类精度分别为95.23%、93.54%和90.12%。在CUB-200-2011数据集,所提方法在第1层级和第2层级的分类精度分别为98.09%和93.66%。结果表明,所提模型的分类准确率优于其他对比模型。 展开更多
关键词 transformER Vision transformer
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Mechanism and Implementation Panths of Low-Altitude Economy in Promoting Transformation and Upgrading of Tourism Industry in Zhejiang Province
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作者 Zhenzi GUO 《Asian Agricultural Research》 2025年第8期13-15,26,共4页
Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds tha... Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds that the low-altitude economy can effectively promote the development of high-end and diversified tourism in Zhejiang by innovating tourism formats,optimizing resource allocation,and enhancing tourist experiences.Besides,it analyzes the current development status of the low-altitude economy in Zhejiang and its potential for integration with tourism,revealing specific enabling pathways for tourism transformation,including low-altitude sightseeing,aviation tourism,and low-altitude sports.Finally,it proposes policy recommendations such as strengthening policy support,enhancing infrastructure development,and cultivating market entities.The findings aim to provide theoretical references and practical guidance for the high-quality development of tourism in Zhejiang Province. 展开更多
关键词 LOW-ALTITUDE ECONOMY transformation and upgrading of the tourism industry Action MECHANISM IMPLEMENTATION path ZHEJIANG Province
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SwinHCAD: A Robust Multi-Modality Segmentation Model for Brain Tumors Using Transformer and Channel-Wise Attention
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作者 Seyong Jin Muhammad Fayaz +2 位作者 L.Minh Dang Hyoung-Kyu Song Hyeonjoon Moon 《Computers, Materials & Continua》 2026年第1期511-533,共23页
Brain tumors require precise segmentation for diagnosis and treatment plans due to their complex morphology and heterogeneous characteristics.While MRI-based automatic brain tumor segmentation technology reduces the b... Brain tumors require precise segmentation for diagnosis and treatment plans due to their complex morphology and heterogeneous characteristics.While MRI-based automatic brain tumor segmentation technology reduces the burden on medical staff and provides quantitative information,existing methodologies and recent models still struggle to accurately capture and classify the fine boundaries and diverse morphologies of tumors.In order to address these challenges and maximize the performance of brain tumor segmentation,this research introduces a novel SwinUNETR-based model by integrating a new decoder block,the Hierarchical Channel-wise Attention Decoder(HCAD),into a powerful SwinUNETR encoder.The HCAD decoder block utilizes hierarchical features and channelspecific attention mechanisms to further fuse information at different scales transmitted from the encoder and preserve spatial details throughout the reconstruction phase.Rigorous evaluations on the recent BraTS GLI datasets demonstrate that the proposed SwinHCAD model achieved superior and improved segmentation accuracy on both the Dice score and HD95 metrics across all tumor subregions(WT,TC,and ET)compared to baseline models.In particular,the rationale and contribution of the model design were clarified through ablation studies to verify the effectiveness of the proposed HCAD decoder block.The results of this study are expected to greatly contribute to enhancing the efficiency of clinical diagnosis and treatment planning by increasing the precision of automated brain tumor segmentation. 展开更多
关键词 Attention mechanism brain tumor segmentation channel-wise attention decoder deep learning medical imaging MRI transformER U-Net
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A Transformer-Based Deep Learning Framework with Semantic Encoding and Syntax-Aware LSTM for Fake Electronic News Detection
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作者 Hamza Murad Khan Shakila Basheer +3 位作者 Mohammad Tabrez Quasim Raja`a Al-Naimi Vijaykumar Varadarajan Anwar Khan 《Computers, Materials & Continua》 2026年第1期1024-1048,共25页
With the increasing growth of online news,fake electronic news detection has become one of the most important paradigms of modern research.Traditional electronic news detection techniques are generally based on contex... With the increasing growth of online news,fake electronic news detection has become one of the most important paradigms of modern research.Traditional electronic news detection techniques are generally based on contextual understanding,sequential dependencies,and/or data imbalance.This makes distinction between genuine and fabricated news a challenging task.To address this problem,we propose a novel hybrid architecture,T5-SA-LSTM,which synergistically integrates the T5 Transformer for semantically rich contextual embedding with the Self-Attentionenhanced(SA)Long Short-Term Memory(LSTM).The LSTM is trained using the Adam optimizer,which provides faster and more stable convergence compared to the Stochastic Gradient Descend(SGD)and Root Mean Square Propagation(RMSProp).The WELFake and FakeNewsPrediction datasets are used,which consist of labeled news articles having fake and real news samples.Tokenization and Synthetic Minority Over-sampling Technique(SMOTE)methods are used for data preprocessing to ensure linguistic normalization and class imbalance.The incorporation of the Self-Attention(SA)mechanism enables the model to highlight critical words and phrases,thereby enhancing predictive accuracy.The proposed model is evaluated using accuracy,precision,recall(sensitivity),and F1-score as performance metrics.The model achieved 99%accuracy on the WELFake dataset and 96.5%accuracy on the FakeNewsPrediction dataset.It outperformed the competitive schemes such as T5-SA-LSTM(RMSProp),T5-SA-LSTM(SGD)and some other models. 展开更多
关键词 Fake news detection tokenization SMOTE text-to-text transfer transformer(T5) long short-term memory(LSTM) self-attention mechanism(SA) T5-SA-LSTM WELFake dataset FakeNewsPrediction dataset
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基于LSTM-Transformer的钢铁工业用户调节潜力预测与优化
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作者 李彬 张雨蒙 周照钒 《电力系统自动化》 北大核心 2026年第5期54-62,共9页
工业用户作为城市用电主体之一,其负荷复杂多变且受用户调节潜力影响较大,传统的预测方法难以准确估计钢铁工业用户的调节能力。为了兼顾负荷波动的不确定性以及钢铁工业用户用电行为的规律性特征,提出了一种基于长短期记忆(LSTM)-Trans... 工业用户作为城市用电主体之一,其负荷复杂多变且受用户调节潜力影响较大,传统的预测方法难以准确估计钢铁工业用户的调节能力。为了兼顾负荷波动的不确定性以及钢铁工业用户用电行为的规律性特征,提出了一种基于长短期记忆(LSTM)-Transformer的钢铁用户调节潜力预测方法。该方法利用LSTM网络捕捉工业负荷可调设备、检修计划和用户调节潜力样本等序列的长期依赖关系提取特征,并通过Transformer模块进行位置编码,利用双层多头自注意力机制捕获数据不同属性间的关系并进行拼接,从而获取多因素影响下的工业用户调节潜力。选取中国天津某钢铁厂的实际运行数据,对4种模型计算潜力值进行对比。实验结果表明,相较于其他模型,所提模型的平均误差降低约40%,具有更高的精度,能够有效反映钢铁工业用户的调节潜力,为优化调度提供有力支持。 展开更多
关键词 LSTM-transformer模型
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基于Enhanced Transformer的铁路客运站节假日客流预测研究
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作者 朱友蓉 李得伟 +2 位作者 李涛 吴迪 李华 《铁道经济研究》 2026年第1期97-108,共12页
节假日作为居民集中出行的高峰期,其客流特征直接关系到铁路运营的安全、运力配置效率和服务质量。节假日期间的铁路客流呈现出与日常显著不同的特殊性,主要表现为长距离出行需求剧增、旅游流与探亲流高度叠加,以及客流分布的时空不均衡... 节假日作为居民集中出行的高峰期,其客流特征直接关系到铁路运营的安全、运力配置效率和服务质量。节假日期间的铁路客流呈现出与日常显著不同的特殊性,主要表现为长距离出行需求剧增、旅游流与探亲流高度叠加,以及客流分布的时空不均衡性,为铁路运营管理带来了挑战。一是客流需求的突增,热门线路和高峰时段的运输能力趋于饱和,传统时间序列模型难以捕捉这种剧烈的非平稳波动;二是预售数据不完整性,旅客购票行为贯穿整个预售期,不同时间点获取的预售数据反映的未来客流信息是动态变化的;三是客流受时间、节假日效应、列车运行安排等多种因素共同影响,这些特征之间存在复杂的非线性耦合关系。为解决上述问题,提出一种基于Enhanced Transformer的铁路客运站节假日客流预测模型。在特征工程方面,主要从时间特征、节假日特征和运营特征3个维度构建了多源特征体系:时间特征包括预售提前量和小时周期编码,用于捕捉旅客出行决策行为和一天内客流的规律性波动;节假日特征涵盖周末指示、节假日标记、节前高峰和节假日周末叠加效应,用于精确捕捉节假日期间客流模式的突变特征;运营特征则提取了每小时上下行列车班次数,反映车站的实时运力供给情况。通过多头自注意力机制,模型能够在不同的表示子空间中并行学习这些多源特征间的复杂交互模式,实现对客流驱动因素的深度理解。创新性地将动态变化的预售数据作为关键输入特征,结合模型的时序信息处理能力,实现对未来客流的滚动预测,突破传统方法在处理预售期动态性上的局限,通过选取苏州地区4个核心铁路客站(苏州北站、苏州站、苏州新区站、苏州园区站)在2025年春节期间的客流数据进行案例分析。实验结果表明,Enhanced Transformer模型对于苏州北站和苏州站等客流规模大的枢纽站,预测准确率可达84.06%,证明了模型在处理高流量、高波动性时间序列数据时的有效性。与Transformer,XGBoost,LSTM,Bi-LSTM的4种基准模型的对比实验显示,Enhanced Transformer在MSE,RMSE,MAE和准确率等所有评估指标上均全面优于其他模型。相较于标准Transformer模型,其预测准确率提升了约6.29%~6.89%;相较于LSTM,准确率提升约3.4%。这些性能提升归因于模型在长序列依赖捕捉、非平稳数据适应和多源特征交互方面的结构优势,为铁路管理部门提供了有力的技术支持,有助于实现节假日期间运力的精准配置、提升旅客服务质量和保障运营安全。 展开更多
关键词 Enhanced transformer
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Multi-source Remote Sensing Image Registration Based on Contourlet Transform and Multiple Feature Fusion 被引量:6
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作者 Huan Liu Gen-Fu Xiao +1 位作者 Yun-Lan Tan Chun-Juan Ouyang 《International Journal of Automation and computing》 EI CSCD 2019年第5期575-588,共14页
Image registration is an indispensable component in multi-source remote sensing image processing. In this paper, we put forward a remote sensing image registration method by including an improved multi-scale and multi... Image registration is an indispensable component in multi-source remote sensing image processing. In this paper, we put forward a remote sensing image registration method by including an improved multi-scale and multi-direction Harris algorithm and a novel compound feature. Multi-scale circle Gaussian combined invariant moments and multi-direction gray level co-occurrence matrix are extracted as features for image matching. The proposed algorithm is evaluated on numerous multi-source remote sensor images with noise and illumination changes. Extensive experimental studies prove that our proposed method is capable of receiving stable and even distribution of key points as well as obtaining robust and accurate correspondence matches. It is a promising scheme in multi-source remote sensing image registration. 展开更多
关键词 Feature fusion multi-scale circle Gaussian combined invariant MOMENT multi-direction GRAY level CO-OCCURRENCE matrix MULTI-SOURCE remote sensing image registration CONTOURLET transform
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基于RF-Transformer的测井曲线页岩岩相识别方法
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作者 苏俊磊 董旭 +4 位作者 唐嘉伟 曾渝 石雪莹 李佩璇 杨仁杰 《测井技术》 2026年第1期153-162,共10页
岩相识别是油气储层精细刻画的关键环节,其准确性直接影响储层评价结果的可靠性。现有识别方法在测井数据高频噪声抑制方面存在不足,且难以准确捕捉地层纵向长程依赖关系。因此,本文提出了一种融合随机森林(Random Forest,RF)与Transfor... 岩相识别是油气储层精细刻画的关键环节,其准确性直接影响储层评价结果的可靠性。现有识别方法在测井数据高频噪声抑制方面存在不足,且难以准确捕捉地层纵向长程依赖关系。因此,本文提出了一种融合随机森林(Random Forest,RF)与Transformer的深度学习模型(RF-Transformer),以提高非均质储层页岩岩相识别的准确性与效率,为储层精细刻画提供技术支撑。该模型首先利用随机森林模型评估测井曲线(如自然伽马、声波时差、电阻率等)特征权重,用以筛选关键参数进而压制高频噪声,构建高质量特征输入向量。随后用Transformer模块,借助其自注意力机制的全局上下文感知能力,并行计算测井曲线的关联权重,从而深度挖掘并重构地层纵向长程依赖关系。以川南页岩气田3800个实测样本(含6类典型岩相、8条常规测井曲线)为数据集,开展模型性能对比与实例应用分析。结果表明:①RF-Transformer模型准确率达91.51%,较Transformer、长短期记忆网络(Long Short-Term Memory,LSTM)和卷积神经网络(Convolutional Neural Network,CNN)模型分别提升了12.90%、23.60%和47.54%,优于K近邻(81.09%)、决策树(77.28%)等传统机器学习模型;②该模型仅需约25次迭代即可进入收敛态,收敛速度较现有模型提升8~10倍;③成功筛选出自然伽马、声波时差、浅侧向电阻率等6条关键测井曲线,有效剔除深侧向电阻率等冗余特征与非地质噪声;④实例应用中,预测页岩岩相剖面纵向连续性与平滑度高,与真实地质分层特征高度吻合,精准刻画页岩岩相过渡带边界。结论认为,该模型在兼顾高抗噪性与强时序捕捉能力的同时,实现页岩岩相的高效精准识别,为非均质储层精细描述提供了可靠技术支撑,后续需围绕测井解释软件适配性展开优化。 展开更多
关键词 线 (Random Forest RF) transformER
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基于LSTM-Transformer模型的突水条件下矿井涌水量预测 被引量:1
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作者 李振华 姜雨菲 +1 位作者 杜锋 王文强 《河南理工大学学报(自然科学版)》 北大核心 2026年第1期77-85,共9页
目的矿井涌水量精准预测对预防矿井水害和保障矿井安全生产具有重要意义,为精准预测矿井涌水量,构建适用于华北型煤田受底板L_(1-4)灰岩含水层和奥陶系灰岩含水层水害威胁的矿井涌水量预测模型。方法以河南某典型矿井的水文监测数据为基... 目的矿井涌水量精准预测对预防矿井水害和保障矿井安全生产具有重要意义,为精准预测矿井涌水量,构建适用于华北型煤田受底板L_(1-4)灰岩含水层和奥陶系灰岩含水层水害威胁的矿井涌水量预测模型。方法以河南某典型矿井的水文监测数据为基础,提出LSTMTransformer模型。利用LSTM捕捉矿井涌水量的动态时序特征,通过Transformer的多头注意力机制分析含水层水位变化和矿井涌水量之间的复杂时序关联,构建水位动态变化驱动下的矿井涌水量精准预测框架。结果结果表明,LSTM-Transformer模型预测精度显著优于LSTM,CNN,Transformer和CNN-LSTM模型的,其均方根误差为20.91 m^(3)/h,平均绝对误差为16.08 m^(3)/h,平均绝对百分比误差为1.12%,且和单因素涌水量预测模型相比,水位-涌水量双因素预测模型预测结果更加稳定。结论LSTM-Transformer模型成功克服传统方法在捕捉复杂水文地质系统中水位-涌水量动态关联上的局限,为矿井涌水量动态预测提供可解释性强、鲁棒性好的解决方案,也为类似地质条件下矿井涌水量预测提供了新方法。 展开更多
关键词 LSTM-transformer耦合模型
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基于BSimilar优化PTransformer的光伏功率短期预测
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作者 张文广 蔡浩 +1 位作者 刘科 孙盼荣 《动力工程学报》 北大核心 2026年第1期77-84,102,共9页
为提高光伏功率短期预测的精度,提出了考虑光伏设备性能退化因素的相似日算法优化的分时段多通道独立光伏功率短期预测方法。首先,在PTransformer模型中用分时段与通道独立的方法来处理光伏输入数据,以降低空间复杂度及提高长时间数据... 为提高光伏功率短期预测的精度,提出了考虑光伏设备性能退化因素的相似日算法优化的分时段多通道独立光伏功率短期预测方法。首先,在PTransformer模型中用分时段与通道独立的方法来处理光伏输入数据,以降低空间复杂度及提高长时间数据序列的关注度。其次,运用Transformer的编码器模型,通过自身注意力机制捕捉光伏序列特征之间的依赖关系,进行光伏功率的短期预测。最后,运用夹角余弦距离计算相似度并考虑光伏设备性能退化因素确定相似日,利用其功率数据优化PTransformer模型,以改善功率数据的滞后性。结果表明:相比典型的光伏功率短期预测方法,所提方法训练速度更快,预测精准度更高,并且对复杂天气状况下的光伏功率也有较好的预测结果。 展开更多
关键词 退 transformER
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Transformer架构驱动下的综采工作面矿压时序特征智能预测
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作者 杜锋 陈博 +7 位作者 王文强 浦海 杜雪明 李国栋 乔瑞 李鑫磊 徐杰 曹煜 《煤田地质与勘探》 北大核心 2026年第2期1-13,共13页
【背景】矿压预测是顶板灾害预警和管理的重要手段,是智能化矿井安全生产的前提和基础。开采过程中综采工作面环境复杂多变,导致基于电液控制系统采集的支架压力数据分布差异较大,预测困难。【方法】基于Transformer的矿压预测模型,使... 【背景】矿压预测是顶板灾害预警和管理的重要手段,是智能化矿井安全生产的前提和基础。开采过程中综采工作面环境复杂多变,导致基于电液控制系统采集的支架压力数据分布差异较大,预测困难。【方法】基于Transformer的矿压预测模型,使用线性插值填补缺失的矿压值,并使用滑动窗口算法调整训练时的矿压数据结构;针对矿压数据的时序特性,构建融合时序特征的输入序列,利用多头注意力(multi-head-attention)机制动态计算权重,根据数据本身自适应地聚焦关键时间步,从而有效捕捉复杂的非线性时序依赖,显著提升特征表征与预测能力,最后使用迁移学习方法,完成对上、中、下工作面支架工作阻力预测,并搭建基于矿压大数据的智能分析及预测平台。【结果和结论】使用多头注意力机制代替神经网络捕捉全局矿压数据特征,比循环神经网络(recurrent neural network,RNN)和长短期记忆网络(long short-term memory,LSTM)具有更强长序列依赖能力和特征学习能力,能有效降低模型损失,更加适用于预测矿压,Transformer模型在测试集上的均方误差和平均绝对误差损失精度分别达到0.34%和2.57%。Transformer模型也具有较强的泛化能力,使用迁移学习方法微调后,能够有效降低模型损失,在迁移同工作面其他支架时具有更好的泛化效果,Transformer预测模型进一步验证在矿压预测问题的适用性和可行性。平台可视化显示系统可精准分析预测前后的来压次数、推进距离、来压判据和工作面矿压云图等关键参数,为顶板灾害预警乃至其他灾害预警提供新思路,也为矿井安全高效开采与智能化建设奠定了坚实基础。 展开更多
关键词 transformer模型
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基于长短期记忆网络-Transformer模型参数优化的锂离子电池剩余使用寿命预测 被引量:1
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作者 高建树 郝世宇 党一诺 《汽车工程师》 2026年第1期32-39,共8页
为提高锂离子电池剩余使用寿命(RUL)预测的准确性,提出了一种基于长短期记忆(LSTM)网络-Transformer模型参数优化的RUL预测方法,采用网格搜索法选取模型的超参数,利用LSTM网络提取锂离子电池时间序列中的长短期依赖关系,使用Transforme... 为提高锂离子电池剩余使用寿命(RUL)预测的准确性,提出了一种基于长短期记忆(LSTM)网络-Transformer模型参数优化的RUL预测方法,采用网格搜索法选取模型的超参数,利用LSTM网络提取锂离子电池时间序列中的长短期依赖关系,使用Transformer的自注意力机制处理全局信息并对超参数进行优化,通过全连接层进行最终的寿命预测。基于美国国家航空航天局(NASA)数据集和先进生命周期工程中心(CALCE)数据集的试验验证结果表明,模型在更短的序列长度、更少的隐藏层数量和训练次数等条件下,在多种评价指标上均优于LSTM网络模型、Transformer模型及其他神经网络模型,具有更高的预测精度和鲁棒性。最后,通过不同电池的对比试验进一步验证了模型在不同电池数据上的泛化能力。 展开更多
关键词 使寿 transformER
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基于局部自注意力Transformer的长期车辆轨迹预测模型
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作者 严利鑫 利健华 +1 位作者 李黄承成 陶璐 《地球信息科学学报》 北大核心 2026年第1期194-208,共15页
【背景】当前城市交通环境复杂且交通流呈现高度非线性特征,现有的基于统计方法、深度学习及注意力机制的预测模型虽已能刻画短期非线性演化,但在城市尺度下面对长时序和强噪声时,仍存在长期依赖表征不足和误差累积明显等问题,不能准确... 【背景】当前城市交通环境复杂且交通流呈现高度非线性特征,现有的基于统计方法、深度学习及注意力机制的预测模型虽已能刻画短期非线性演化,但在城市尺度下面对长时序和强噪声时,仍存在长期依赖表征不足和误差累积明显等问题,不能准确实现车辆长期轨迹预测。【方法】针对上述问题,本文提出一种基于局部自注意力Transformer的长期车辆轨迹预测模型。该模型基于城市车辆轨迹数据局部相关性强与易受噪声干扰的特性,以局部自注意力机制替代了传统Transformer的全局自注意力结构,并在数据预处理、嵌入层及输出方式等方面进行了适配车辆轨迹的调整,采用离散高维嵌入增强输入轨迹的空间表达,构建双独立嵌入向量和解码结构以提升坐标预测精度,从而提升了对轨迹数据的捕获能力。【结果】基于罗马320辆出租车连续一个月GPS轨迹数据所开展的实验结果表明,所提模型在短、中、长期预测任务的平均误差和单步误差均优于主流基线模型,平均位移误差和均方根误差分别最大下降了41%和35%。此外,进一步分析表明,适当的局部自注意力时间窗能够提高模型对轨迹特征的捕获能力,而当时间窗从最优的30 min扩大至35 min和40 min时,平均位移误差相较30 min分别上升约3.78%与5.17%,说明过大的时间窗会引入额外噪声并削弱模型的预测性能。【结论】研究成果可为个性化导航推荐、实时交通管理和轨迹数据恢复等实际应用提供技术方法和数据支持。 展开更多
关键词 GPS transformer模型
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