期刊文献+
共找到727篇文章
< 1 2 37 >
每页显示 20 50 100
Information Hiding Method Based on Block DWT Sub-Band Feature Encoding
1
作者 Qiudong SUN Wenxin MA +1 位作者 Wenying YAN Hong DAI 《Journal of Software Engineering and Applications》 2009年第5期383-387,共5页
For realizing of long text information hiding and covert communication, a binary watermark sequence was obtained firstly from a text file and encoded by a redundant encoding method. Then, two neighboring blocks were s... For realizing of long text information hiding and covert communication, a binary watermark sequence was obtained firstly from a text file and encoded by a redundant encoding method. Then, two neighboring blocks were selected at each time from the Hilbert scanning sequence of carrier image blocks, and transformed by 1-level discrete wavelet transformation (DWT). And then the double block based JNDs (just noticeable difference) were calculated with a visual model. According to the different codes of each two watermark bits, the average values of two corresponding detail sub-bands were modified by using one of JNDs to hide information into carrier image. The experimental results show that the hidden information is invisible to human eyes, and the algorithm is robust to some common image processing operations. The conclusion is that the algorithm is effective and practical. 展开更多
关键词 sub-band feature encoding REDUNDANT encoding Visual Model Discrete WAVELET TRANSFORMATION Information Hiding
在线阅读 下载PDF
A Fine-Grained RecognitionModel based on Discriminative Region Localization and Efficient Second-Order Feature Encoding
2
作者 Xiaorui Zhang Yingying Wang +3 位作者 Wei Sun Shiyu Zhou Haoming Zhang Pengpai Wang 《Computers, Materials & Continua》 2026年第4期946-965,共20页
Discriminative region localization and efficient feature encoding are crucial for fine-grained object recognition.However,existing data augmentation methods struggle to accurately locate discriminative regions in comp... Discriminative region localization and efficient feature encoding are crucial for fine-grained object recognition.However,existing data augmentation methods struggle to accurately locate discriminative regions in complex backgrounds,small target objects,and limited training data,leading to poor recognition.Fine-grained images exhibit“small inter-class differences,”and while second-order feature encoding enhances discrimination,it often requires dual Convolutional Neural Networks(CNN),increasing training time and complexity.This study proposes a model integrating discriminative region localization and efficient second-order feature encoding.By ranking feature map channels via a fully connected layer,it selects high-importance channels to generate an enhanced map,accurately locating discriminative regions.Cropping and erasing augmentations further refine recognition.To improve efficiency,a novel second-order feature encoding module generates an attention map from the fourth convolutional group of Residual Network 50 layers(ResNet-50)and multiplies it with features from the fifth group,producing second-order features while reducing dimensionality and training time.Experiments on Caltech-University of California,San Diego Birds-200-2011(CUB-200-2011),Stanford Car,and Fine-Grained Visual Classification of Aircraft(FGVC Aircraft)datasets show state-of-the-art accuracy of 88.9%,94.7%,and 93.3%,respectively. 展开更多
关键词 Fine-grained recognition feature encoding data augmentation second-order feature discriminative regions
在线阅读 下载PDF
Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
3
作者 Shi Li Didi Sun 《Computers, Materials & Continua》 SCIE EI 2025年第1期1069-1086,共18页
With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions... With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying reasons.This comprehension is crucial for making informed strategic decisions in various business and societal contexts.However,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause extraction.To address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment mechanisms.The model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause pairs.Second,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among tasks.The proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 score.Experimental results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its effectiveness.This research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-cause pair extraction.However,the study’s limitation lies in the data sources,potentially restricting the generalizability of the findings. 展开更多
关键词 Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms
在线阅读 下载PDF
Improve Fractal Compression Encoding Speed Using Feature Extraction and Self-organization Network 被引量:1
4
作者 Berthe Kya, Yang Yang Information Engineering School. University of Science and Technology Beijing. Beijing 100083. China 《Journal of University of Science and Technology Beijing》 CSCD 2001年第4期306-310,共5页
Image compression consists of two main parts: encoding and decoding. One of the important problems of the fractal theory is the long encoding implementation time, which hindered the acceptance of fractal image compres... Image compression consists of two main parts: encoding and decoding. One of the important problems of the fractal theory is the long encoding implementation time, which hindered the acceptance of fractal image compression as a practical method. The long encoding time results from the need to perform a large number of domain-range matches, the total encoding time is the product of the number of matches and the time to perform each match. In order to improve encoding speed, a hybrid method combining features extraction and self-organization network has been provided, which is based on the feature extraction approach the comparison pixels by pixels between the feature of range blocks and domains blocks. The efficiency of the new method was been proved by examples. 展开更多
关键词 image compression fractal theory features extraction self-organization network fractal encoding
在线阅读 下载PDF
Prediction of Pediatric Sepsis Using a Deep Encoding Network with Cross Features
5
作者 陈潇 张瑞 +1 位作者 汤心溢 钱娟 《Journal of Shanghai Jiaotong university(Science)》 EI 2024年第1期131-140,共10页
Sepsis poses a serious threat to health of children in pediatric intensive care unit.The mortality from pediatric sepsis can be effectively reduced through in-time diagnosis and therapeutic intervention.The bacillicul... Sepsis poses a serious threat to health of children in pediatric intensive care unit.The mortality from pediatric sepsis can be effectively reduced through in-time diagnosis and therapeutic intervention.The bacilliculture detection method is too time-consuming to receive timely treatment.In this research,we propose a new framework:a deep encoding network with cross features(CF-DEN)that enables accurate early detection of sepsis.Cross features are automatically constructed via the gradient boosting decision tree and distilled into the deep encoding network(DEN)we designed.The DEN is aimed at learning sufficiently effective representation from clinical test data.Each layer of the DEN fltrates the features involved in computation at current layer via attention mechanism and outputs the current prediction which is additive layer by layer to obtain the embedding feature at last layer.The framework takes the advantage of tree-based method and neural network method to extract effective representation from small clinical dataset and obtain accurate prediction in order to prompt patient to get timely treatment.We evaluate the performance of the framework on the dataset collected from Shanghai Children's Medical Center.Compared with common machine learning methods,our method achieves the increase on F1-score by 16.06%on the test set. 展开更多
关键词 pediatric sepsis gradient boosting decision tree cross feature neural network deep encoding network with cross features(CF-DEN)
原文传递
Feature Enhanced Stacked Auto Encoder for Diseases Detection in Brain MRI 被引量:1
6
作者 Umair Muneer Butt Rimsha Arif +2 位作者 Sukumar Letchmunan Babur Hayat Malik Muhammad Adil Butt 《Computers, Materials & Continua》 SCIE EI 2023年第8期2551-2570,共20页
The detection of brain disease is an essential issue in medical and research areas.Deep learning techniques have shown promising results in detecting and diagnosing brain diseases using magnetic resonance imaging(MRI)... The detection of brain disease is an essential issue in medical and research areas.Deep learning techniques have shown promising results in detecting and diagnosing brain diseases using magnetic resonance imaging(MRI)images.These techniques involve training neural networks on large datasets of MRI images,allowing the networks to learn patterns and features indicative of different brain diseases.However,several challenges and limitations still need to be addressed further to improve the accuracy and effectiveness of these techniques.This paper implements a Feature Enhanced Stacked Auto Encoder(FESAE)model to detect brain diseases.The standard stack auto encoder’s results are trivial and not robust enough to boost the system’s accuracy.Therefore,the standard Stack Auto Encoder(SAE)is replaced with a Stacked Feature Enhanced Auto Encoder with a feature enhancement function to efficiently and effectively get non-trivial features with less activation energy froman image.The proposed model consists of four stages.First,pre-processing is performed to remove noise,and the greyscale image is converted to Red,Green,and Blue(RGB)to enhance feature details for discriminative feature extraction.Second,feature Extraction is performed to extract significant features for classification using DiscreteWavelet Transform(DWT)and Channelization.Third,classification is performed to classify MRI images into four major classes:Normal,Tumor,Brain Stroke,and Alzheimer’s.Finally,the FESAE model outperforms the state-of-theart,machine learning,and deep learning methods such as Artificial Neural Network(ANN),SAE,Random Forest(RF),and Logistic Regression(LR)by achieving a high accuracy of 98.61% on a dataset of 2000 MRI images.The proposed model has significant potential for assisting radiologists in diagnosing brain diseases more accurately and improving patient outcomes. 展开更多
关键词 Brain diseases deep learning feature enhanced stacked auto encoder stack auto encoder
在线阅读 下载PDF
Enhanced Multimodal Sentiment Analysis via Integrated Spatial Position Encoding and Fusion Embedding
7
作者 Chenquan Gan Xu Liu +3 位作者 Yu Tang Xianrong Yu Qingyi Zhu Deepak Kumar Jain 《Computers, Materials & Continua》 2025年第12期5399-5421,共23页
Multimodal sentiment analysis aims to understand emotions from text,speech,and video data.However,current methods often overlook the dominant role of text and suffer from feature loss during integration.Given the vary... Multimodal sentiment analysis aims to understand emotions from text,speech,and video data.However,current methods often overlook the dominant role of text and suffer from feature loss during integration.Given the varying importance of each modality across different contexts,a central and pressing challenge in multimodal sentiment analysis lies in maximizing the use of rich intra-modal features while minimizing information loss during the fusion process.In response to these critical limitations,we propose a novel framework that integrates spatial position encoding and fusion embedding modules to address these issues.In our model,text is treated as the core modality,while speech and video features are selectively incorporated through a unique position-aware fusion process.The spatial position encoding strategy preserves the internal structural information of speech and visual modalities,enabling the model to capture localized intra-modal dependencies that are often overlooked.This design enhances the richness and discriminative power of the fused representation,enabling more accurate and context-aware sentiment prediction.Finally,we conduct comprehensive evaluations on two widely recognized standard datasets in the field—CMU-MOSI and CMU-MOSEI to validate the performance of the proposed model.The experimental results demonstrate that our model exhibits good performance and effectiveness for sentiment analysis tasks. 展开更多
关键词 Multimodal sentiment analysis spatial position encoding fusion embedding feature loss reduction
在线阅读 下载PDF
A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection
8
作者 Zhong Qu Guoqing Mu Bin Yuan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期255-273,共19页
Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this field.However,as the performance of cr... Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this field.However,as the performance of crack detection in cement pavement improves,the depth and width of the network structure are significantly increased,which necessitates more computing power and storage space.This limitation hampers the practical implementation of crack detection models on various platforms,particularly portable devices like small mobile devices.To solve these problems,we propose a dual-encoder-based network architecture that focuses on extracting more comprehensive fracture feature information and combines cross-fusion modules and coordinated attention mechanisms formore efficient feature fusion.Firstly,we use small channel convolution to construct shallow feature extractionmodule(SFEM)to extract low-level feature information of cracks in cement pavement images,in order to obtainmore information about cracks in the shallowfeatures of images.In addition,we construct large kernel atrous convolution(LKAC)to enhance crack information,which incorporates coordination attention mechanism for non-crack information filtering,and large kernel atrous convolution with different cores,using different receptive fields to extract more detailed edge and context information.Finally,the three-stage feature map outputs from the shallow feature extraction module is cross-fused with the two-stage feature map outputs from the large kernel atrous convolution module,and the shallow feature and detailed edge feature are fully fused to obtain the final crack prediction map.We evaluate our method on three public crack datasets:DeepCrack,CFD,and Crack500.Experimental results on theDeepCrack dataset demonstrate the effectiveness of our proposed method compared to state-of-the-art crack detection methods,which achieves Precision(P)87.2%,Recall(R)87.7%,and F-score(F1)87.4%.Thanks to our lightweight crack detectionmodel,the parameter count of the model in real-world detection scenarios has been significantly reduced to less than 2M.This advancement also facilitates technical support for portable scene detection. 展开更多
关键词 Shallow feature extraction module large kernel atrous convolution dual encoder lightweight network crack detection
在线阅读 下载PDF
EFFECTIVE FEATURE ANALYSIS FOR COLOR IMAGE SEGMENTATION 被引量:2
9
作者 黎宁 毛四新 李有福 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期206-212,共7页
An approach for color image segmentation is proposed based on the contributions of color features to segmentation rather than the choice of a particular color space. The determination of effective color features depen... An approach for color image segmentation is proposed based on the contributions of color features to segmentation rather than the choice of a particular color space. The determination of effective color features depends on the analysis of various color features from each tested color image via the designed feature encoding. It is different from the pervious methods where self organized feature map (SOFM) is used for constructing the feature encoding so that the feature encoding can self organize the effective features for different color images. Fuzzy clustering is applied for the final segmentation when the well suited color features and the initial parameter are available. The proposed method has been applied in segmenting different types of color images and the experimental results show that it outperforms the classical clustering method. The study shows that the feature encoding approach offers great promise in automating and optimizing the segmentation of color images. 展开更多
关键词 image segmentation color image neural networks fuzzy clustering feature encoding
在线阅读 下载PDF
Anti-noise sound recognition based on energy-frequency feature
10
作者 ZHOU Xiaomin LI Ying 《智能系统学报》 CSCD 北大核心 2015年第5期810-819,共10页
In the natural environment,non-stationary background noise affects the animal sound recognition directly.Given this problem,a new technology of animal sound recognition based on energy-frequency(E-F)feature is propose... In the natural environment,non-stationary background noise affects the animal sound recognition directly.Given this problem,a new technology of animal sound recognition based on energy-frequency(E-F)feature is proposed in this paper.The animal sound is turned into spectrogram to show the energy,time and frequency characteristics.The sub-band frequency division and sub-band energy division are carried out on the spectrogram for extracting the statistical characteristic of energy and frequency,so as to achieve sub-band power distribution(SPD)and sub-band division.Radon transform(RT)and discrete wavelet transform(DWT)are employed to obtain the important projection coefficients,and the energy values of sub-band frequencies are calculated to extract the sub-band frequency feature.The E-F feature is formed by combining the SPD feature and sub-band energy value feature.The classification is achieved by support vector machine(SVM)classifier.The experimental results show that the method can achieve better recognition effect even when the SNR is below10 dB. 展开更多
关键词 animal sound recognition sub-band power distribution(SPD) sub-band FREQUENCY feature RADON transform(RT) energy-frequency(E-F)feature
在线阅读 下载PDF
基于线性注意和类别关联特征学习的在线动作检测 被引量:1
11
作者 詹永照 孙慧敏 +1 位作者 夏惠芬 任晓鹏 《江苏大学学报(自然科学版)》 北大核心 2026年第1期39-47,63,共10页
为了在在线动作检测中充分合理利用动作的上下文特征、与类别关联的特征和预测的未来特征快速检测相应动作,提出基于线性注意和类别关联特征学习的在线动作检测方法.该方法改进了Transformer构架,采用哈达玛积的轻型线性自注意实现Trans... 为了在在线动作检测中充分合理利用动作的上下文特征、与类别关联的特征和预测的未来特征快速检测相应动作,提出基于线性注意和类别关联特征学习的在线动作检测方法.该方法改进了Transformer构架,采用哈达玛积的轻型线性自注意实现Transformer视频上下文特征学习,以减少计算开销;其次对训练样本动作特征进行聚类,将视频序列上下文特征与动作类别特征进行关联学习,有效获得与类别关联的特征表达;最后融合动作的上下文特征、与类别关联的特征和预测的未来特征检测相应时刻动作,以提升动作鉴别性.在典型数据集上进行性能试验,完成了超参取值分析,对比了不同方法的工作精度和运行效率.给出了消融试验和可视化分析.结果表明:在Thumos14(TSN-Anet)、Thumos14(TSN-Kinetics)和HDD数据集上,所提出方法的mAP比Colar方法分别提高了0.2、0.5、0.2百分点,可见新方法优于目前较先进的Colar方法. 展开更多
关键词 在线动作检测 深度学习 注意力机制 编码 上下文特征 TRANSFORMER 类别关联特征学习
在线阅读 下载PDF
基于多尺度编码器融合的三维人体姿态估计算法
12
作者 包晓安 陈恩琳 +3 位作者 张娜 涂小妹 吴彪 张庆琪 《浙江大学学报(工学版)》 北大核心 2026年第3期565-573,584,共10页
针对冗余信息干扰与信息完整性需求之间的矛盾,提出基于多尺度编码器融合的三维人体姿态估计方法.该方法由关键帧时空编码器(KFSTE)和全局保留自注意力编码器(GRSAE)构成.KFSTE通过关键帧选择器对骨架特征序列进行筛选后,由时间编码器... 针对冗余信息干扰与信息完整性需求之间的矛盾,提出基于多尺度编码器融合的三维人体姿态估计方法.该方法由关键帧时空编码器(KFSTE)和全局保留自注意力编码器(GRSAE)构成.KFSTE通过关键帧选择器对骨架特征序列进行筛选后,由时间编码器获取局部时空建模.GRSAE通过保留编码器进行全局单阶段编码来获取全局骨架序列特征,避免因关键帧筛选偏差导致的信息损失.通过对双编码器的特征拼接及回归处理,预测得到三维人体姿态坐标.实验结果表明,在较大规模的Human3.6M数据集上,所提方法的平均关节位置误差(MPJPE)比MixSTE低3%,有11个动作获得最佳. 展开更多
关键词 三维人体姿态估计 时空编码器 关键帧提取 保留自注意力编码 多编码特征融合
在线阅读 下载PDF
利用编码器-解码器的温室温湿度长序列预测
13
作者 盖荣丽 王鹏飞 +1 位作者 郭志斌 段立明 《小型微型计算机系统》 北大核心 2026年第1期89-96,共8页
针对现有温湿度预测模型难以充分考虑温室温湿度数据本身的复杂非线性特征和长期依赖关系,导致模型在实际应用中预测精度不足问题,本文提出了一种基于编码器-解码器架构的多层结构温湿度预测模型.模型通过卷积运算对数据进行多尺度转换... 针对现有温湿度预测模型难以充分考虑温室温湿度数据本身的复杂非线性特征和长期依赖关系,导致模型在实际应用中预测精度不足问题,本文提出了一种基于编码器-解码器架构的多层结构温湿度预测模型.模型通过卷积运算对数据进行多尺度转换和特征提取,并使用改进的双向限制性耦合长短期记忆网络(Bidirectional Restrictive Coupled Long-Short Term Memory,BiRCLSTM)优化了信息传递机制,同时运用多头注意力机制从不同的表示子空间中捕捉信息,最终实现了长序列多变量温室温湿度数据的精确预测.在自建温湿度数据集中,该模型的预测误差明显优于基线模型,并且该模型还在3个公共数据集上进行了不同时间分辨率的预测实验,综合实验结果表明,本文模型在温室温湿度预测中具有更高的精度和良好的泛化性能. 展开更多
关键词 温湿度预测 长时间序列 多变量特征 编码器-解码器 长短期记忆网络
在线阅读 下载PDF
CMFuseNet:一种结合局部和全局特征的裂缝分割模型
14
作者 刘恒洋 周聪 邵桂芳 《重庆理工大学学报(自然科学)》 北大核心 2026年第3期247-256,共10页
裂缝是建筑结构损伤的早期征兆,及时识别与处理裂缝对结构维护至关重要。然而,现有基于卷积神经网络(convolutional neural network,CNN)的裂缝分割方法在背景干扰严重、裂缝拓扑结构复杂的情况下,仍存在分割精度不足和抗干扰能力弱的... 裂缝是建筑结构损伤的早期征兆,及时识别与处理裂缝对结构维护至关重要。然而,现有基于卷积神经网络(convolutional neural network,CNN)的裂缝分割方法在背景干扰严重、裂缝拓扑结构复杂的情况下,仍存在分割精度不足和抗干扰能力弱的问题。为此,提出了一种结合CNN与Mamba的双编码分支裂缝分割模型(CMFuseNet)。该模型融合CNN强大的局部特征提取能力与Mamba优异的全局上下文建模能力,以增强对裂缝局部纹理细节与全局拓扑结构的感知。此外,设计了频域引导特征校准模块(frequency-guided feature calibration module,FFCM),用于校准双编码分支融合后的特征,抑制跨域结合引入的噪声并增强特征间相关性。在Volker和TUT公开数据集上的实验表明,CMFuseNet在背景干扰强、裂缝细小等挑战性场景下,性能均优于5种先进对比方法,并以82.35%和83.16%的F 1分数在各自数据集上达到最优。 展开更多
关键词 裂缝分割 局部和全局特征 双编码器架构 特征校准
在线阅读 下载PDF
基于双重注意力机制的传统服饰图像检索
15
作者 王明远 张优贤 《毛纺科技》 北大核心 2026年第2期110-116,共7页
针对传统服饰图像检索过程中特征描述符构建粗糙、特征编码冗余度高、图像特征提取不充分的问题,提出一种基于双重注意力机制的传统服饰图像检索方法。该方法利用差分成像方法重构传统服饰图像,将重构后图像输入多尺度通道注意力机制中... 针对传统服饰图像检索过程中特征描述符构建粗糙、特征编码冗余度高、图像特征提取不充分的问题,提出一种基于双重注意力机制的传统服饰图像检索方法。该方法利用差分成像方法重构传统服饰图像,将重构后图像输入多尺度通道注意力机制中,获取传统服饰图像多尺度特征;将该特征输入自注意力机制自主学习,获取包含空间和位置信息的特征图;经由2个全连接层组成的哈希网络对特征图编码,计算特征图编码之间的汉明距离;设定三元组量化约束,降低该距离的计算误差,获取前N个结果作为传统服饰图像检索结果。测试结果显示:该方法重构后图像的色彩饱满且不失真,并且信息系数均在0.929以上,弗雷谢特感知距离均低于0.016,能够依据设定的损失函数进行训练并输出检索结果。 展开更多
关键词 注意力机制 传统服饰 图像检索 特征图编码 汉明距离 三元组量化约束
在线阅读 下载PDF
基于注意力和变分类自编码的PCB小样本缺陷检测
16
作者 宋涛 冉璐 +4 位作者 杨金河 邢镔 龙邹荣 王泓俊 李梓谦 《计算机工程与应用》 北大核心 2026年第4期363-372,共10页
针对小样本印刷电路板(printed circuit board,PCB)缺陷样本少、样本失衡、难泛化导致检测精度较低的问题,引入元学习方案,在元学习目标检测框架上提出基于注意力和变分类自编码的小样本缺陷检测方法。针对支持分支建模易受噪声影响问题... 针对小样本印刷电路板(printed circuit board,PCB)缺陷样本少、样本失衡、难泛化导致检测精度较低的问题,引入元学习方案,在元学习目标检测框架上提出基于注意力和变分类自编码的小样本缺陷检测方法。针对支持分支建模易受噪声影响问题,提出基于注意力的背景弱化模块,通过对注意力机制进行改进,使模型能够自适应改变重要性,聚焦前景信息与周围差异,减少背景干扰。鉴于支持分支缺乏类特征提取,导致查询特征与支持特征聚合后容易发生漏检、错检的问题,提出变分类自编码模块,利用概率分布以及重参数化获得类特征,提高新类检测准确率。为了充分探索查询特征与支持特征高级特征关系,提出多特征聚合模块,利用元素乘法、减法运算对两种特征之间的相似点和差异性进行建模,同时通过查询原型减少随机采样带来的噪声。实验结果表明,在PKU-Market-PCB数据集上,该方法在10样本下新类、基类准确率最高可达到65.3%、89.7%。 展开更多
关键词 小样本目标检测 元学习 注意力机制 变分类自编码 多特征聚合
在线阅读 下载PDF
基于参数自适应FMD和SDAE的变负载下轴承故障诊断
17
作者 何勇 刘晓玲 《振动与冲击》 北大核心 2026年第2期189-200,共12页
针对堆叠降噪自编码器(stacked denoisingauto-encoder,SDAE)网络在强噪声干扰及变负载工况下难以准确识别滚动轴承故障特征这一难题,提出一种基于特征模态分解(feature mode decomposition,FMD)与SDAE相结合的滚动轴承故障诊断方法。首... 针对堆叠降噪自编码器(stacked denoisingauto-encoder,SDAE)网络在强噪声干扰及变负载工况下难以准确识别滚动轴承故障特征这一难题,提出一种基于特征模态分解(feature mode decomposition,FMD)与SDAE相结合的滚动轴承故障诊断方法。首先,采用信号自相关函数对传统基尼系数进行改进;其次,以改进基尼系数作为模态分量评价指标,建立了参数自适应FMD方法,并采用该方法对SDAE网络输入信号进行降噪;最后,将降噪后信号的包络谱输入到SDAE网络中并得到滚动轴承变负载工况下的故障类型诊断结果。基于3个开源数据集的算例分析表明,该方法能够有效提升SDAE网络的滚动轴承故障诊断准确率。通过与其他方法的对比,验证了该方法具有更好的稳定性和更高的故障诊断准确率。 展开更多
关键词 故障诊断 滚动轴承 堆叠降噪自编码器(SDAE) 参数自适应特征模态分解(FMD) 变负载工况
在线阅读 下载PDF
基于改进型BERT预训练模型的大规模文本语义匹配方法
18
作者 周晓飞 《西昌学院学报(自然科学版)》 2026年第1期84-92,102,共10页
大规模文本数据具有数据量庞大的特点,且同一词汇在不同语境下可能具有完全不同的含义。仅依赖固定规则或模型,难以适应动态的语义变化,这会导致信息丢失和语义不完整。在这种情况下,无法捕捉到深层次的语义信息和语境关系,进而影响语... 大规模文本数据具有数据量庞大的特点,且同一词汇在不同语境下可能具有完全不同的含义。仅依赖固定规则或模型,难以适应动态的语义变化,这会导致信息丢失和语义不完整。在这种情况下,无法捕捉到深层次的语义信息和语境关系,进而影响语义匹配的准确性。为解决这一问题,本文提出基于改进型双向编码器表征(bidirectional encoder representations from transformers,BERT)模型的大规模文本语义匹配方法。该改进的BERT预训练模型通过文本词向量的位置编码来增强文本的语境信息特征,从而有效捕捉文本的语境信息。此外,采用注意力机制动态计算特征融合权重,并通过加权融合方法生成文本的融合语义特征。通过文本特征信息提取、多维知识编码、融合语义标签生成以及语义匹配关系预测4个步骤,评估待匹配文本之间的语义一致性。本文设定一致性阈值为0.8,即当预测值超过0.8时,认为待匹配文本具有较高的语义一致性,从而实现准确的文本语义匹配。实验结果表明,基于大规模文本样本数据得到的平均倒数排名(mean reciprocal rank,MRR)高于0.7,且与对比方法相比,匹配结果更加准确。 展开更多
关键词 改进型BERT预训练模型 融合特征 位置编码 文本向量化 注意力机制 语义匹配
在线阅读 下载PDF
基于多特征融合的修船结算编码智能匹配复合模型
19
作者 朱安庆 朱碧玉 +1 位作者 姚飚 李同兰 《造船技术》 2026年第1期23-30,共8页
在一些修船企业建立的修船结算系统和电子价格库中,人工匹配结算编码步骤易出错且耗时长,直接影响结算效率。为解决该问题,提出一种基于多特征融合的修船结算编码智能匹配复合模型。采用来自变换器的双向编码器表示(Bidirectional Encod... 在一些修船企业建立的修船结算系统和电子价格库中,人工匹配结算编码步骤易出错且耗时长,直接影响结算效率。为解决该问题,提出一种基于多特征融合的修船结算编码智能匹配复合模型。采用来自变换器的双向编码器表示(Bidirectional Encoder Representations from Transformers,BERT)模型将工程内容文本表示为词向量,采用卷积神经网络(Convolutional Neural Network,CNN)模型提取文本的局部特征,采用双向长短期记忆网络结合注意力机制(Bidirectional Long Short-Term Memory with Attention Mechanism,BiLSTM-Attention)模型提取上下文特征,得到对应的结算编码。试验结果表明,所提出的复合模型在整体准确率方面实现显著提升,充分证明该复合模型在处理复杂文本分类任务中的优势。 展开更多
关键词 修船结算编码智能匹配复合模型 多特征融合 来自变换器的双向编码器表示模型 卷积神经网络模型 双向长短期记忆网络结合注意力机制模型
在线阅读 下载PDF
基于机器学习的线谱特征提取方法
20
作者 师俊杰 熊凌霜 孙大军 《船舶力学》 北大核心 2026年第1期159-167,共9页
针对人工提取线谱特征方法的不足,本文对线谱特征提取原理进行研究,提出一种基于机器学习的线谱特征提取方法。搭建基于卷积神经网络的编码器-解码器,并在卷积和池化层间引入注意力机制,使输入数据的重要特征占据更高的权重,从而提高特... 针对人工提取线谱特征方法的不足,本文对线谱特征提取原理进行研究,提出一种基于机器学习的线谱特征提取方法。搭建基于卷积神经网络的编码器-解码器,并在卷积和池化层间引入注意力机制,使输入数据的重要特征占据更高的权重,从而提高特征提取的准确度。将模型与U-Net模型和TPSW算法在低信噪比情况下进行比较,并在实际数据上进行测试。实验结果表明,在谱级信噪比为5 dB时,改进模型线定位精度可达到0.823,在0~5 dB时均优于U-Net模型和TPSW算法,达到了提取线谱有效信息,提高水下目标检测准确率的目的。 展开更多
关键词 线谱特征提取 机器学习 编码-解码器 水下目标检测
在线阅读 下载PDF
上一页 1 2 37 下一页 到第
使用帮助 返回顶部