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PHASE TRANSFORMATION UNIT OF BAINITIC FERRITE AND ITS SURFACE RELIEF IN LOW AND MEDIUM CARBON ALLOY STEELS
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作者 YU Degang CHEN Dajun ZHENG Jinghong HE Yirong SHEN Fufa Shanghai Jiaotong University,Shanghai,China Professor,Department of Materials Science and Engineering,Shanghai Jiaotong University,1954 Huashan Road,Shanghai 200030,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第3期161-167,共7页
The lath-or plate-shaped bainitic ferrite of low and medium carbon alloy steels consists of packets of ferrite sublaths which are composed of many finer and regular ferrite blocks.They are uniform shear growth units o... The lath-or plate-shaped bainitic ferrite of low and medium carbon alloy steels consists of packets of ferrite sublaths which are composed of many finer and regular ferrite blocks.They are uniform shear growth units of bainitic phase transformation.No carbide is precipitated from them.The bainitic O-carbides are precipitated from γ-α interface or carbon-rich austenite.The mode of arrangement of the units in ferrite sublath packet is in uni-or bi-di- rection.Single surface relief is produced by the accumulation of uniform shear strains with all the ferrite units arranged unidirectionally in a sublath packet,while tent-shaped surface relief is formed by the integration of the uniform shear strains of two groups with ferrite units piling up in two directions and growing face to face;whereas if they grow back to back,the integra- tion will be responsible for invert-tent-shaped surface relief.The interface trace between two groups of ferrite units in a sublath packet is shown as“midrib”. 展开更多
关键词 low and medium carbon alloy steels BAINITE FERRITE phase transformation unit surface relief
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A Gauge Transformation between Ragnisco-Tu Hierarchy and a Related Lattice Hierarchy
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作者 Yuqing Liu Chao Hu Juan Dai 《Journal of Applied Mathematics and Physics》 2015年第10期1282-1294,共13页
A new lattice hierarchy related to Ragnisco-Tu equation is proposed and its gauge equivalence to Ragnisco-Tu equation is proven. As an application of gauge transformation, we construct Darboux transformation (DT) of t... A new lattice hierarchy related to Ragnisco-Tu equation is proposed and its gauge equivalence to Ragnisco-Tu equation is proven. As an application of gauge transformation, we construct Darboux transformation (DT) of this new equation through DT of Ragnisco-Tu equation. An explicit exact solution is presented as an example. 展开更多
关键词 Ragnisco-tu HIERARCHY GAUGE transformation Transfer OPERATOR DARBOUX transformation
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基于门控循环单元和Transformer的车辆轨迹预测方法
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作者 王庆荣 谭小泽 +1 位作者 朱昌锋 李裕杰 《汽车技术》 CSCD 北大核心 2024年第7期1-8,共8页
为增强自动驾驶车辆对动态环境的理解能力及其道路行驶安全性,提出基于门控循环单元(GRU)和Transformer的车辆轨迹预测模型STGTF,使用GRU提取车辆的历史轨迹特征,通过双层多头注意力(MHA)机制提取车辆的时空交互特征,生成预测轨迹。试... 为增强自动驾驶车辆对动态环境的理解能力及其道路行驶安全性,提出基于门控循环单元(GRU)和Transformer的车辆轨迹预测模型STGTF,使用GRU提取车辆的历史轨迹特征,通过双层多头注意力(MHA)机制提取车辆的时空交互特征,生成预测轨迹。试验结果表明,预测结果的均方根误差(RMSE)平均降低7.3%,STGTF在短期预测和长期预测方面均有不同程度的提升,验证了模型的有效性。 展开更多
关键词 车辆轨迹预测 门控循环单元 transformER 车辆交互 多头注意力机制
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Following the Charter of the United Nations: The Basic Guarantee for the Realization of the Right to Development——From the Perspective of Transforming Our World: the 2030 Agenda for Sustainable Development 被引量:5
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作者 赵建文 《The Journal of Human Rights》 2016年第5期485-508,共24页
This study discusses the basic guarantee of the Charter of the United Nations to realize the right to development from the angle of Transforming Our World: the 2030 Agenda for Sustainable Development. The concepts reg... This study discusses the basic guarantee of the Charter of the United Nations to realize the right to development from the angle of Transforming Our World: the 2030 Agenda for Sustainable Development. The concepts regarding the people as the focal point, the dignity, the worth of the human being, as well as larger aspects of freedom, and other basic concepts within the Charter of the United Nations, guide the right direction of action for the realization of the right to development. The purpose and principles of the United Nations establishment in the Charter constitute the basic legal protection of the right to development. Values of peace, international dialogue, and international cooperation show the right path to the realization of the right to development. 展开更多
关键词 Charter of the united Nations right to development transforming Our World:the 2030 Agenda for Sustainable Development
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一种基于安全多方计算的快速Transformer安全推理方案 被引量:1
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作者 刘伟欣 管晔玮 +3 位作者 霍嘉荣 丁元朝 郭华 李博 《计算机研究与发展》 EI CSCD 北大核心 2024年第5期1218-1229,共12页
Transformer模型在自然语言处理、计算机视觉等众多领域得到了广泛应用,并且有着突出的表现.在Transformer的推理应用中用户的数据会被泄露给模型提供方.随着数据隐私问题愈发得到公众的关注,上述数据泄露问题引发了学者们对Transforme... Transformer模型在自然语言处理、计算机视觉等众多领域得到了广泛应用,并且有着突出的表现.在Transformer的推理应用中用户的数据会被泄露给模型提供方.随着数据隐私问题愈发得到公众的关注,上述数据泄露问题引发了学者们对Transformer安全推理的研究,使用安全多方计算(secure multi-party computation,MPC)实现Transformer模型的安全推理是当前的一个研究热点.由于Transformer模型中存在大量非线性函数,因此使用MPC技术实现Transformer安全推理会造成巨大的计算和通信开销.针对Transformer安全推理过程中开销较大的Softmax注意力机制,提出了2种MPC友好的注意力机制Softmax freeDiv Attention和2Quad freeDiv Attention.通过将Transformer模型中的Softmax注意力机制替换为新的MPC友好的注意力机制,同时结合激活函数GeLU的替换以及知识蒸馏技术,提出了一个MPC友好的Transformer转换框架,通过将Transformer模型转化为MPC友好的Transformer模型,提高Transformer安全推理的效率.在局域网环境下使用安全处理器(secure processing unit,SPU)提供的隐私计算协议,基于所提出的MPC友好的Transformer转换框架,在SST-2上使用Bert-Base进行安全推理.测试结果表明,在保持推理准确率与无近似模型一致的情况下,安全推理计算效率提高2.26倍. 展开更多
关键词 安全推理 transformER 安全多方计算 安全处理器 知识蒸馏
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BSTFNet:An Encrypted Malicious Traffic Classification Method Integrating Global Semantic and Spatiotemporal Features 被引量:1
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作者 Hong Huang Xingxing Zhang +2 位作者 Ye Lu Ze Li Shaohua Zhou 《Computers, Materials & Continua》 SCIE EI 2024年第3期3929-3951,共23页
While encryption technology safeguards the security of network communications,malicious traffic also uses encryption protocols to obscure its malicious behavior.To address the issues of traditional machine learning me... While encryption technology safeguards the security of network communications,malicious traffic also uses encryption protocols to obscure its malicious behavior.To address the issues of traditional machine learning methods relying on expert experience and the insufficient representation capabilities of existing deep learning methods for encrypted malicious traffic,we propose an encrypted malicious traffic classification method that integrates global semantic features with local spatiotemporal features,called BERT-based Spatio-Temporal Features Network(BSTFNet).At the packet-level granularity,the model captures the global semantic features of packets through the attention mechanism of the Bidirectional Encoder Representations from Transformers(BERT)model.At the byte-level granularity,we initially employ the Bidirectional Gated Recurrent Unit(BiGRU)model to extract temporal features from bytes,followed by the utilization of the Text Convolutional Neural Network(TextCNN)model with multi-sized convolution kernels to extract local multi-receptive field spatial features.The fusion of features from both granularities serves as the ultimate multidimensional representation of malicious traffic.Our approach achieves accuracy and F1-score of 99.39%and 99.40%,respectively,on the publicly available USTC-TFC2016 dataset,and effectively reduces sample confusion within the Neris and Virut categories.The experimental results demonstrate that our method has outstanding representation and classification capabilities for encrypted malicious traffic. 展开更多
关键词 Encrypted malicious traffic classification bidirectional encoder representations from transformers text convolutional neural network bidirectional gated recurrent unit
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User space transformation in deep learning based recommendation
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作者 WU Caihua MA Jianchao +1 位作者 ZHANG Xiuwei XIE Dang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期674-684,共11页
Deep learning based recommendation methods, such as the recurrent neural network based recommendation method(RNNRec) and the gated recurrent unit(GRU) based recommendation method(GRURec), are proposed to solve the pro... Deep learning based recommendation methods, such as the recurrent neural network based recommendation method(RNNRec) and the gated recurrent unit(GRU) based recommendation method(GRURec), are proposed to solve the problem of time heterogeneous feedback recommendation. These methods out-perform several state-of-the-art methods. However, in RNNRec and GRURec, action vectors and item vectors are shared among users. The different meanings of the same action for different users are not considered. Similarly, different user preference for the same item is also ignored. To address this problem, the models of RNNRec and GRURec are modified in this paper. In the proposed methods, action vectors and item vectors are transformed into the user space for each user firstly, and then the transformed vectors are fed into the original neural networks of RNNRec and GRURec. The transformed action vectors and item vectors represent the user specified meaning of actions and the preference for items, which makes the proposed method obtain more accurate recommendation results. The experimental results on two real-life datasets indicate that the proposed method outperforms RNNRec and GRURec as well as other state-of-the-art approaches in most cases. 展开更多
关键词 recommender system collaborative filtering time heterogeneous feedback recurrent neural network gated recurrent unit(GRU) user space transformation
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Predicting Wavelet-Transformed Stock Prices Using a Vanishing Gradient Resilient Optimized Gated Recurrent Unit with a Time Lag
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作者 Luyandza Sindi Mamba Antony Ngunyi Lawrence Nderu 《Journal of Data Analysis and Information Processing》 2023年第1期49-68,共20页
The development of accurate prediction models continues to be highly beneficial in myriad disciplines. Deep learning models have performed well in stock price prediction and give high accuracy. However, these models a... The development of accurate prediction models continues to be highly beneficial in myriad disciplines. Deep learning models have performed well in stock price prediction and give high accuracy. However, these models are largely affected by the vanishing gradient problem escalated by some activation functions. This study proposes the use of the Vanishing Gradient Resilient Optimized Gated Recurrent Unit (OGRU) model with a scaled mean Approximation Coefficient (AC) time lag which should counter slow convergence, vanishing gradient and large error metrics. This study employed the Rectified Linear Unit (ReLU), Hyperbolic Tangent (Tanh), Sigmoid and Exponential Linear Unit (ELU) activation functions. Real-life datasets including the daily Apple and 5-minute Netflix closing stock prices were used, and they were decomposed using the Stationary Wavelet Transform (SWT). The decomposed series formed a decomposed data model which was compared to an undecomposed data model with similar hyperparameters and different default lags. The Apple daily dataset performed well with a Default_1 lag, using an undecomposed data model and the ReLU, attaining 0.01312, 0.00854 and 3.67 minutes for RMSE, MAE and runtime. The Netflix data performed best with the MeanAC_42 lag, using decomposed data model and the ELU achieving 0.00620, 0.00487 and 3.01 minutes for the same metrics. 展开更多
关键词 Optimized Gated Recurrent unit Approximation Coefficient Stationary Wavelet transform Activation Function Time Lag
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A Brief Review on the Evolution and Transformation of Universities in UK
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作者 Jiedan Wang 《教育研究前沿(中英文版)》 2020年第3期203-206,共4页
This paper is expected to make a brief review on the evolution and development of universities in United Kingdom from the‘Medieval Universities’taking Oxbridge as representatives to the‘New Universities’in twentie... This paper is expected to make a brief review on the evolution and development of universities in United Kingdom from the‘Medieval Universities’taking Oxbridge as representatives to the‘New Universities’in twentieth century,with entrepreneurial universities emerging in the twenty first century being included.The conclusion can be drawn from the brief review that when the“old”universities didn’t meet the social demand yet with the unshakable position,the newly learning institution comes into being in the history of HE in United Kingdom.Moreover,each category of universities possesses different characteristics and style. 展开更多
关键词 UNIVERSITIES EVOLUTION transformation united Kingdom
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Division of high resolution sequence stratigraphy units with wavelet transform of logs in Dagang Oilfield
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作者 Ying ZHANG Baozhi PAN +1 位作者 Buzhou HUANG Linfu XUE 《Global Geology》 2007年第1期69-73,共5页
Division of high resolution sequence stratigraphy units based on wavelet transform of logging data is found to be good at identifying subtle cycles of geological process in Kongnan area of Dagang Oilfield. The anal- y... Division of high resolution sequence stratigraphy units based on wavelet transform of logging data is found to be good at identifying subtle cycles of geological process in Kongnan area of Dagang Oilfield. The anal- ysis of multi-scales gyre of formation with 1-D continuous Dmey wavelet transform of log curve (GR) and I-D discrete Daubechies wavelet transform of log curve (Rt) all make the division of sequence interfaces more objec- tive and precise, which avoids the artificial influence with core analysis and the uncertainty with seismic data and core analysis. 展开更多
关键词 high resolution sequence stratigraphy units logging data wavelet transform
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基于对抗训练与Transformer的风力发电机故障分类方法
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作者 王言国 吕鹏远 +4 位作者 兰金江 刘明哲 秦冠军 张硕桦 周宇 《计算机工程》 CAS CSCD 北大核心 2024年第9期377-384,共8页
风力发电机故障分类的复杂性和多样性严重影响风能发电效率,传统的人工方法效率低下,准确率较低,已有的深度学习模型在真实环境中易受数据噪声干扰而表现不佳。为提升风力发电机故障分类模型在真实环境下的分类性能与鲁棒性,提出一种基... 风力发电机故障分类的复杂性和多样性严重影响风能发电效率,传统的人工方法效率低下,准确率较低,已有的深度学习模型在真实环境中易受数据噪声干扰而表现不佳。为提升风力发电机故障分类模型在真实环境下的分类性能与鲁棒性,提出一种基于对抗训练与Transformer的故障分类方法。首先通过引入一维卷积与门控线性单元(GLU)增强注意力机制对局部特征的学习,保留易被忽略的局部信息,提升模型对于局部特征的敏感度。其次结合限制因子约束对抗样本,提高对抗样本产生的准确性。最后在消除错误样本的同时反馈生成过程,使其具备更好的抗干扰能力。实验结果表明,与5种常用的分类模型相比,所提模型分类性能平均提升7.76%,与真实结果之间的误差最小。局部增强的注意力机制和所提的对抗训练方法分别使模型的分类性能平均提升4.51%、4.95%。所提模型在10%~20%噪声环境中仍保持较好性能,增强了其在真实环境中的稳定性。该方法在提高分类准确率的同时使模型具备更强的泛化能力,对于提升风力发电机故障分类性能与鲁棒性具有重要意义。 展开更多
关键词 风力发电机 门控线性单元 transformer模型 对抗训练 故障分类
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Price prediction of power transformer materials based on CEEMD and GRU
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作者 Yan Huang Yufeng Hu +2 位作者 Liangzheng Wu Shangyong Wen Zhengdong Wan 《Global Energy Interconnection》 EI CSCD 2024年第2期217-227,共11页
The rapid growth of the Chinese economy has fueled the expansion of power grids.Power transformers are key equipment in power grid projects,and their price changes have a significant impact on cost control.However,the... The rapid growth of the Chinese economy has fueled the expansion of power grids.Power transformers are key equipment in power grid projects,and their price changes have a significant impact on cost control.However,the prices of power transformer materials manifest as nonsmooth and nonlinear sequences.Hence,estimating the acquisition costs of power grid projects is difficult,hindering the normal operation of power engineering construction.To more accurately predict the price of power transformer materials,this study proposes a method based on complementary ensemble empirical mode decomposition(CEEMD)and gated recurrent unit(GRU)network.First,the CEEMD decomposed the price series into multiple intrinsic mode functions(IMFs).Multiple IMFs were clustered to obtain several aggregated sequences based on the sample entropy of each IMF.Then,an empirical wavelet transform(EWT)was applied to the aggregation sequence with a large sample entropy,and the multiple subsequences obtained from the decomposition were predicted by the GRU model.The GRU model was used to directly predict the aggregation sequences with a small sample entropy.In this study,we used authentic historical pricing data for power transformer materials to validate the proposed approach.The empirical findings demonstrated the efficacy of our method across both datasets,with mean absolute percentage errors(MAPEs)of less than 1%and 3%.This approach holds a significant reference value for future research in the field of power transformer material price prediction. 展开更多
关键词 Power transformer material Price prediction Complementary ensemble empirical mode decomposition Gated recurrent unit Empirical wavelet transform
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基于Transformer的短时交通流时空预测 被引量:1
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作者 杨国亮 习浩 +1 位作者 龚家仁 温钧林 《计算机应用与软件》 北大核心 2024年第3期169-173,225,共6页
现有的交通流预测模型未能全面获取路网的空间依赖,忽略了周期性对交通流量的影响,且缺乏对全局时间依赖的建模能力。针对以上问题,提出一种结合Transformer的动态扩散卷积门控循环单元预测模型。该模型利用动态扩散卷积网络和门控循环... 现有的交通流预测模型未能全面获取路网的空间依赖,忽略了周期性对交通流量的影响,且缺乏对全局时间依赖的建模能力。针对以上问题,提出一种结合Transformer的动态扩散卷积门控循环单元预测模型。该模型利用动态扩散卷积网络和门控循环单元对交通流的近期、日周期和周周期三个时间进行时空建模;使用Transformer层获取全局时间依赖关系;将各组件输出进行加权融合,生成预测结果。实验结果表明,该方法相较基准模型能有效降低预测误差,准确预测交通演化态势。 展开更多
关键词 短时交通流预测 扩散卷积 门控循环单元 transformER
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Analysis on unit maximum capacity of orthogonal multiple watermarking for multimedia signals in B5G wireless communications
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作者 Mianjie Li Senfeng Lai +4 位作者 Jiao Wang Zhihong Tian Nadra Guizani Xiaojiang Du Chun Shan 《Digital Communications and Networks》 SCIE CSCD 2024年第1期38-44,共7页
Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user ... Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of B5G.The multiwatermarking process employs spread transform dither modulation.During the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading vectors.Consequently,multiple watermarks can be simultaneously embedded into the same position of a multimedia signal.Moreover,the multiple watermarks can be extracted without affecting one another during the extraction process.We analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility. 展开更多
关键词 B5G Multimedia information security Spread transform dither modulation Spreading vector measurement unit maximum capacity
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Aerial target threat assessment based on gated recurrent unit and self-attention mechanism
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作者 CHEN Chen QUAN Wei SHAO Zhuang 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期361-373,共13页
Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties ... Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced features.Subsequently, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning. 展开更多
关键词 target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)
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情感分析的跨模态Transformer组合模型
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作者 王亮 王屹 王军 《计算机工程与应用》 CSCD 北大核心 2024年第13期124-135,共12页
基于Transformer的端到端组合深度学习模型是多模态情感分析的主流模型。针对相关工作中此类模型存在的低资源(low-resource)模态数据的情感特征提取能力不足、不同模态非对齐数据的特征尺度差异导致对齐融合过程中易丢失关键特征信息... 基于Transformer的端到端组合深度学习模型是多模态情感分析的主流模型。针对相关工作中此类模型存在的低资源(low-resource)模态数据的情感特征提取能力不足、不同模态非对齐数据的特征尺度差异导致对齐融合过程中易丢失关键特征信息、基础注意力模型并行处理多模态数据导致多模态长期依赖机制不可靠的问题,提出了一种基于轻量级注意力聚合模块与跨模态Transformer的能使用多模态非对齐数据执行二分类和多分类任务的多模态情感分析模型LAACMT。LAACMT模型提出采用门控循环单元与改进的特征提取算法提取低资源模态信息,提出位置编码配合卷积放缩方法用于对齐多模态语境,提出跨模态多头注意力机制融合已对齐的多模态数据并建立可靠的跨模态长期依赖机制。LAACMT模型在包含文本、语音和视频的三种模态非对齐数据集CMU-MOSI上的实验结果表明该模型的性能评价指标较SOTA有稳定提升。其中Acc7提升了3.96%、Acc2提升了4.08%、F1分数提升了3.35%。消融实验结果数据证明所提模型解决了多模态情感分析相关工作中存在的问题,降低了基于Transformer的多模态情感分析模型的复杂度,提升了模型性能的同时避免了过拟合问题。 展开更多
关键词 多模态情感分析 轻量级注意力聚合模块 跨模态transformer 门控循环单元 跨模态多头注意力机制
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SDH/SONET低阶支路VT/TU映射芯片实现 被引量:6
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作者 叶波 李天望 +1 位作者 张立军 罗敏 《光通信技术》 CSCD 北大核心 2009年第3期14-17,共4页
设计了SDH/SONET的低阶支路VT/TU映射芯片,单片实现28通道DS1/VC-11或21通道E1/VC-12到7个VTG/TUG-2的映射及逆映射,或DS1/E1/VC的组合到VTG/TUG-2的混合映射。该芯片带有支路环回和指针处理功能,支持UPSR环形网络拓扑结构。采用TSMC 0... 设计了SDH/SONET的低阶支路VT/TU映射芯片,单片实现28通道DS1/VC-11或21通道E1/VC-12到7个VTG/TUG-2的映射及逆映射,或DS1/E1/VC的组合到VTG/TUG-2的混合映射。该芯片带有支路环回和指针处理功能,支持UPSR环形网络拓扑结构。采用TSMC 0.13μm CMOS工艺流片成功,电路规模约23.7万门。 展开更多
关键词 SDH/SONET VT/tu 映射 芯片
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基于DSP的配电变压器远方终端单元(TTU)的设计 被引量:7
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作者 李光辉 陈志英 《电工电能新技术》 CSCD 2004年第3期72-75,共4页
本文介绍基于DSP的配电变压器远方终端单元(TTU)的研制方案,着重介绍了其系统硬件和软件设计及谐波分析的实现。该终端单元具有实时监测电网各种参数值,可选择不同的通信接口与主机实现双向通信的功能。
关键词 变压器远方终端单元 谐波分析 TMS320LF2407A SA9904A
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黄瓜(Cucumis sativus L.)果瘤基因Tu表达载体构建及遗传转化 被引量:1
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作者 任国良 杨绪勤 +2 位作者 何欢乐 蔡润 潘俊松 《上海交通大学学报(农业科学版)》 2014年第3期89-94,共6页
为了进一步优化黄瓜遗传转化体系,提高遗传转化效率,构建含有自身启动子的黄瓜果瘤基因(Tu)表达载体pCAMBIA2301-Tu,将表达载体通过电击法导入农杆菌菌株GV3101中,进行农杆菌介导的黄瓜遗传转化的研究。使用限制性内切酶KpnI和BamHI对质... 为了进一步优化黄瓜遗传转化体系,提高遗传转化效率,构建含有自身启动子的黄瓜果瘤基因(Tu)表达载体pCAMBIA2301-Tu,将表达载体通过电击法导入农杆菌菌株GV3101中,进行农杆菌介导的黄瓜遗传转化的研究。使用限制性内切酶KpnI和BamHI对质粒pCAMBIA2301和Tu基因PCR产物进行双酶切,回收目的片段,连接后成功构建Tu基因表达载体。通过优化遗传转化的生根条件以及抑制农杆菌生长条件,一定程度上提高了遗传转化的效率。580个外植体通过抗生素筛选获得的18株再生苗进行PCR检测和测序鉴定,最终获得8株阳性转化苗,转化效率为1.37%。 展开更多
关键词 黄瓜 果瘤基因 载体构建 遗传转化
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一种基于Transformer的三维人体姿态估计方法 被引量:4
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作者 王玉萍 曾毅 +1 位作者 李胜辉 张磊 《图学学报》 CSCD 北大核心 2023年第1期139-145,共7页
三维人体姿态估计是人类行为理解的基础,但是预测出合理的三维人体姿态序列仍然是具有挑战性的问题。为了解决这个问题,提出一种基于Transformer的三维人体姿态估计方法,利用多层长短期记忆(LSTM)单元和多尺度Transformer结构增强人体... 三维人体姿态估计是人类行为理解的基础,但是预测出合理的三维人体姿态序列仍然是具有挑战性的问题。为了解决这个问题,提出一种基于Transformer的三维人体姿态估计方法,利用多层长短期记忆(LSTM)单元和多尺度Transformer结构增强人体姿态序列预测的准确性。首先,设计基于时间序列的生成器,通过ResNet预训练神经网络提取图像特征;其次,采用多层LSTM单元学习时间连续性的图像序列中人体姿态之间的关系,输出合理的SMPL人体参数模型序列;最后,构建基于多尺度Transformer的判别器,利用多尺度Transformer结构对多个分割粒度进行细节特征学习,尤其是Transformerblock对相对位置进行编码增强局部特征学习能力。实验结果表明,该方法相对于VIBE方法具有更好地预测精度,在3DPW数据集上比VIBE的平均(每)关节位置误差(MPJPE)低了7.5%;在MP-INF-3DHP数据集上比VIBE的MPJPE降低了1.8%。 展开更多
关键词 多尺度transformer结构 LSTM单元 时间序列 注意力机制 三维姿态估计
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