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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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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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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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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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Denoising of Medical Images Using Multiwavelet Transforms and Various Thresholding Techniques 被引量:1
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作者 Abdullah Al Jumah Mohammed Gulam Ahamad Syed Amjad Ali 《Journal of Signal and Information Processing》 2013年第1期24-32,共9页
The problem of estimating an image corrupted by additive white Gaussian noise has been of interest for practical reasons. Non-linear denoising methods based on wavelets, have become popular but Multiwavelets outperfor... The problem of estimating an image corrupted by additive white Gaussian noise has been of interest for practical reasons. Non-linear denoising methods based on wavelets, have become popular but Multiwavelets outperform wavelets in image denoising. Multiwavelets are wavelets with several scaling and wavelet functions, offer simultaneously Orthogonality, Symmetry, Short support and Vanishing moments, which is not possible with ordinary (scalar) wavelets. These properties make Multiwavelets promising for image processing applications, such as image denoising. The aim of this paper is to apply various non-linear thresholding techniques such as hard, soft, universal, modified universal, fixed and multivariate thresholding in Multiwavelet transform domain such as Discrete Multiwavelet Transform, Symmetric Asymmetric (SA4), Chui Lian (CL), and Bi-Hermite (Bih52S) for different Multiwavelets at different levels, to denoise an image and determine the best one out of it. The performance of denoising algorithms and various thresholding are measured using quantitative performance measures such as, Mean Square Error (MSE), and Root Mean Square Error (RMSE), Signal-to-Noise Ratio (SNR), Peak Signal-to-Noise Ratio (PSNR). It is found that CL Multiwavelet transform in combination with modified universal thresholding has given best results. 展开更多
关键词 MULTIWAVELETS Noise THRESHOLDING Additive White Gaussian Noise SIGNAL-TO-NOISE Ratio Discrete MULTIWAVELET transforms Chui Lian Symmetric Asymmetric MULTIWAVELET transform Bi-Hermite MULTIWAVELET transform Modified Universal THRESHOLDING
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结合双路径骨干与Transformer增强的道路场景检测方法
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作者 邱云飞 姚曦彤 辛浩 《计算机工程与应用》 北大核心 2026年第2期302-312,共11页
道路场景检测要求模型能够做出快速和精确的判断,然而在实际场景中由于目标尺度间的差异、误检及漏检情况,导致小模型不太准确,而大模型速度较慢。针对上述问题,提出一种结合双路径骨干与Transformer增强的道路场景检测方法(Dynamic-DAN... 道路场景检测要求模型能够做出快速和精确的判断,然而在实际场景中由于目标尺度间的差异、误检及漏检情况,导致小模型不太准确,而大模型速度较慢。针对上述问题,提出一种结合双路径骨干与Transformer增强的道路场景检测方法(Dynamic-DANet)。提出复合双路径骨干网络,通过级联高分辨率与低分辨率骨干,促进骨干网络语义特征与空间细节的交互。提出邻层特征交互网络,通过逐层地对相邻层特征进行拼接,并引入加权系数自适应地捕获不同层级特征,利用Transformer增强的自注意机制促进全局上下文信息的融合。应用MPDIoU边界回归损失函数,进一步简化模型计算量,加速模型收敛。以复合双路径骨干网络为基础,基于多尺度特征设计分类路由,实现模型动态决策。在KITTI和BDD100K数据集上验证所提方法的有效性,平均检测精度值(mAP)分别达到了88.7%和40.2%,检测速度(FPS)分别实现了每秒178帧和每秒166帧。相较于主流的YOLOv7-tiny、YOLOv8和YOLOv10等算法在评价指标数值和可视化效果上均有明显改善。实验结果表明,所提方法提升了复杂道路场景下的检测性能,并且实现了将两个静态检测器融合为一个动态检测器,以更优的计算消耗实现更佳的检测效果。 展开更多
关键词 视觉transformer MPDIoU
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基于多尺度特征提取与ResNet-Transformer的抽油机故障诊断
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作者 韩东颖 朱志洲 +1 位作者 葛子轩 时培明 《计量学报》 北大核心 2026年第1期35-41,共7页
提出了一种多尺度特征提取与ResNet-Transformer算法用于抽油机故障诊断。首先,利用深度残差网络ResNet-34的局部特征提取能力捕获示功图空间细节,并借助Transformer编码器上下文建模能力获取全局特征,构建了端到端的抽油机故障诊断框架... 提出了一种多尺度特征提取与ResNet-Transformer算法用于抽油机故障诊断。首先,利用深度残差网络ResNet-34的局部特征提取能力捕获示功图空间细节,并借助Transformer编码器上下文建模能力获取全局特征,构建了端到端的抽油机故障诊断框架;其次,引入多尺度特征提取模块,通过1×1、3×3和5×5卷积核并行提取不同尺度的特征信息,增强对示功图细节的感知能力;最后,设计了特征融合注意力机制,自适应地整合多尺度特征和全局语义信息。在包含7种典型工况的示功图数据集上进行实验,结果表明,该算法在故障诊断任务中取得了94%准确率,验证了所提算法的有效性。 展开更多
关键词 ResNet-transformer模型
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Paving Pathways to Progress:Global South youth explore China’s agricultural innovation and rural transformation
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作者 LI XIAOYU 《ChinAfrica》 2026年第2期36-37,共2页
From lecture halls in Beijing to villages in the mountains of southwest China,a group of young rural innovators from Global South countries recently embarked on a journey that connected policy thinking,technological p... From lecture halls in Beijing to villages in the mountains of southwest China,a group of young rural innovators from Global South countries recently embarked on a journey that connected policy thinking,technological practice and lived rural experience. 展开更多
关键词 paving pathways progress rural transformation global south youth lecture halls mountains southwest china chinas agricultural innovation beijing
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Sumudu Transformation or What Else Can Laplace Transformation Do
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2019年第2期111-142,共32页
The transition from a known Taylor series ?of a known function f(x) to a new function ?primarily defined by the infinite power series ?with coefficients f(n)(0)?from the Taylor series of the function f(x)?can be made ... The transition from a known Taylor series ?of a known function f(x) to a new function ?primarily defined by the infinite power series ?with coefficients f(n)(0)?from the Taylor series of the function f(x)?can be made by an integral transformation which is a modified Laplace transformation and is called Sumudu transformation. It makes the transition from the Exponential series to the Geometric series and may help to evaluate new infinite power series from known Taylor series. The Sumudu transformation is demonstrated to be a limiting case of Fractional integration. Apart from the basic Sumudu integral transformation we discuss a modification where the coefficients ?from the Taylor series are not changed to f(n)(0)?but only to . Beside simple examples our applications are mainly concerned to calculate new Generating functions for Hermite polynomials from the basic ones. 展开更多
关键词 Mellin transformATION Fractional Integration Geometric SERIES and Exponential SERIES Error Function Laguerre POLYNOMIALS Generating FUNCTIONS of Hermite POLYNOMIALS BESSEL FUNCTIONS Asymptotic SERIES Operator IDENTITIES
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Influences of blood lipids on the occurrence and prognosis of hemorrhagic transformation after acute cerebral infarction: a case-control study of 732 patients 被引量:67
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作者 Gang Lv Guo-Qiang Wang +5 位作者 Zhen-Xi Xia Hai-Xia Wang Nan Liu Wei Wei Yong-Hua Huang Wei-Wei Zhang 《Military Medical Research》 SCIE CAS CSCD 2019年第3期189-200,共12页
Background: To study the influence of blood lipid levels on hemorrhagic transformation(HT) and prognosis after acute cerebral infarction(ACI).Methods: Patients with ACI within 72 h of symptoms onset between January 1 ... Background: To study the influence of blood lipid levels on hemorrhagic transformation(HT) and prognosis after acute cerebral infarction(ACI).Methods: Patients with ACI within 72 h of symptoms onset between January 1 st, 2015, and December 31 st, 2016, were retrospectively analyzed. Patients were divided into group A(without HT) and group B(HT). The outcomes were assessed after 3 months of disease onset using the modified Rankin Scale(m RS). An m RS score of 0–2 points indicated excellent prognosis, and an m RS score of 3–6 points indicated poor prognosis.Results: A total of 732 patients conformed to the inclusion criteria, including 628 in group A and 104 in group B. The incidence of HT was 14.2%, and the median onset time was 2 d(interquartile range, 1–7 d). The percentages of patients with large infarct size and cortex involvement in group B were 80.8% and 79.8%, respectively, which were both significantly higher than those in group A(28.7 and 33.4%, respectively). The incidence rate of atrial fibrillation(AF) in group B was significantly higher than that in group A(39.4% vs. 13.9%, P<0.001). The adjusted multivariate analysis results showed that large infarct size, cortex involvement and AF were independent risk factors of HT, while total cholesterol(TC) was a protective factor of HT(OR=0.359, 95% CI 0.136–0.944, P=0.038). With every 1 mmol/L reduction in normal TC levels, the risk of HT increased by 64.1%. The mortality and morbidity at 3 months in group B(21.2% and 76.7%, respectively) were both significantly higher than those in group A(8.0% and 42.8%, respectively). The adjusted multivariate analysis results showed that large infarct size(OR=12.178, 95% CI 5.390–27.516, P<0.001) was an independent risk factor of long-term unfavorable outcomes, whereas low-density lipoprotein cholesterol(LDL-C) was a protective factor(OR=0.538, 95% CI 0.300–0.964, P=0.037). With every 1 mmol/L reduction in normal LDL-C levels, the risk of an unfavorable outcome increased by 46.2%. Major therapies, including intravenous recombinant human tissue plasminogen activator(r TPA), intensive lipid-lowering statins and anti-platelets, were not significantly related to either HT or long-term, post-ACI poor prognosis.Conclusions: For patients with large infarct sizes, especially those with cortex involvement, AF, or lower levels of TC, the risk of HT might increase after ACI. The risk of a long-term unfavorable outcome in these patients might increase with a reduction in LDL-C. 展开更多
关键词 Acute cerebral infarction HEMORRHAGIC transformation Total cholesterol Low-density LIPOPROTEIN Intensive LIPID-LOWERING STATINS ANTI-PLATELET Atrial FIBRILLATION modified Rankin scale
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