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Information Hiding Method Based on Block DWT Sub-Band Feature Encoding
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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
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Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
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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
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Prediction of Pediatric Sepsis Using a Deep Encoding Network with Cross Features
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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)
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A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection
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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
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Improve Fractal Compression Encoding Speed Using Feature Extraction and Self-organization Network 被引量:1
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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
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Feature Enhanced Stacked Auto Encoder for Diseases Detection in Brain MRI 被引量:1
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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
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EFFECTIVE FEATURE ANALYSIS FOR COLOR IMAGE SEGMENTATION 被引量:2
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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
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Anti-noise sound recognition based on energy-frequency feature
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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
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卷积自编码器和残差循环神经网络在刀具剩余寿命预测中的应用 被引量:1
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作者 周学良 潘晓明 吴瑶 《机械科学与技术》 北大核心 2025年第5期806-813,共8页
针对刀具剩余寿命预测问题,提出了一种将一维卷积自编码器(One-dimensional convolutional auto encoder,1DCAE)和残差双向门控循环单元(Residual bidirectional gated recurrent unit,RBGRU)相结合的预测方法。通过1DCAE连续卷积池化... 针对刀具剩余寿命预测问题,提出了一种将一维卷积自编码器(One-dimensional convolutional auto encoder,1DCAE)和残差双向门控循环单元(Residual bidirectional gated recurrent unit,RBGRU)相结合的预测方法。通过1DCAE连续卷积池化和反卷积上采样方法获取工况信号的深层特征,并将其与分段后的原始信号融合后作为刀具剩余寿命的表征;同时结合残差网络的思想对双向门控循环单元(Bidirectional gated recurrent unit,BiGRU)的结构进行改进以增强对时序特征的捕获能力。实验结果表明,该方法比其他算法具有更高的预测精度。 展开更多
关键词 刀具 剩余寿命预测 卷积自编码器 残差门控循环单元 特征融合
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基于多尺度卷积自编码器的船舶逆变器故障诊断 被引量:1
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作者 崔博文 张思远 《舰船科学技术》 北大核心 2025年第3期135-140,共6页
为实现对船舶逆变器的有效维护,确保船舶逆变器模块的正常运行,提出一种基于多尺度特征融合和降噪卷积自编码器的船舶逆变器开路故障诊断方法。可以直接对一维原始电流数据自适应地提取数据特征,降低信号内的噪声,实现端到端的故障诊断... 为实现对船舶逆变器的有效维护,确保船舶逆变器模块的正常运行,提出一种基于多尺度特征融合和降噪卷积自编码器的船舶逆变器开路故障诊断方法。可以直接对一维原始电流数据自适应地提取数据特征,降低信号内的噪声,实现端到端的故障诊断。首先,利用数据增强方法来增强数据集;其次,根据数据特点设计可以提取局部细节和整体结构信息的多尺度卷积特征融合模块,并在编码器中引入该模块,形成特征提取模型;最后,利用全连接神经网络对模型输出的数据特征进行分类,根据分类结果实现故障诊断。实验结果表明,所提出的方法具有优越的数据特征提取性能及噪声鲁棒性能,可以实现船舶逆变器开关器件开路故障诊断。 展开更多
关键词 船舶逆变器 故障诊断 多尺度特征融合 卷积自编码器
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基于多层特征嵌入的单目标跟踪算法
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作者 才华 周鸿策 +1 位作者 付强 赵义武 《兵工学报》 北大核心 2025年第3期333-348,共16页
针对现有视觉目标跟踪方法仅使用初始帧的目标单一外观特征,导致当背景复杂或外观发生剧烈变化时跟踪失效的问题,提出一种基于多层特征嵌入的单目标跟踪算法。增强目标的外观区分度,使用稀疏内嵌注意力机制编码器,嵌入具有高实例区分度... 针对现有视觉目标跟踪方法仅使用初始帧的目标单一外观特征,导致当背景复杂或外观发生剧烈变化时跟踪失效的问题,提出一种基于多层特征嵌入的单目标跟踪算法。增强目标的外观区分度,使用稀疏内嵌注意力机制编码器,嵌入具有高实例区分度的外观特征;采用类间特征聚合编码器嵌入目标的类别信息,在外观发生变化时保持类内的紧凑性;同时将预测的历史帧跟踪框坐标转化为目标运动轨迹特征嵌入,为算法提供高置信度的时间上下文特征。研究结果表明:所提算法在OTB100基准测试中成功率和准确率分别达到71.4%和92.6%,在GOT-10K、LaSOT、TrackingNet共3个大规模公开数据上取得了鲁棒的效果,成功率分别达到64.9%、72.0%和78.7%;基于多层特征嵌入的单目标跟踪算法有效地克服了现有算法的局限,具有较好的准确性和鲁棒性。 展开更多
关键词 目标跟踪 稀疏内嵌注意力机制编码器 类间特征聚合编码器 运动特征嵌入
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基于自注意力机制的高分遥感影像语义分割 被引量:2
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作者 杨军 张金影 康玥 《哈尔滨工程大学学报》 北大核心 2025年第2期344-354,共11页
针对遥感影像多尺度特征提取困难、上下文信息利用不足的问题,本文结合自注意力机制和深度可分离卷积提出一种线性多头自注意力网络模型,适用于高分辨率遥感影像语义分割。在自注意力模块之前引入深度可分离卷积,减少计算量的同时有助... 针对遥感影像多尺度特征提取困难、上下文信息利用不足的问题,本文结合自注意力机制和深度可分离卷积提出一种线性多头自注意力网络模型,适用于高分辨率遥感影像语义分割。在自注意力模块之前引入深度可分离卷积,减少计算量的同时有助于捕获局部特征;在编码器分支中提出线性的多头自注意力模块以降低模型的计算复杂度;设计一个解码器来恢复特征图分辨率,通过级联操作整合各层级的特征并生成高分辨率的语义分割结果。所提算法在ISPRS Vaihingen和Potsdam数据集上的分割结果的mF1分别达到了90.77%和92.36%,与目前主流算法相比,不透水表面、建筑、低矮植物、树木类的分割准确率及总体分割准确率均有提高。本文算法构建的线性多头自注意力网络是一种高效的高分辨率遥感影像语义分割模型。 展开更多
关键词 高分辨率遥感影像 多头自注意力 深度可分离卷积 语义分割 特征提取 卷积神经网络 编码器 解码器
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三维人体姿态估计中的多尺度时空特征融合
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作者 张宇 刘骊 +2 位作者 付晓东 刘利军 彭玮 《计算机辅助设计与图形学学报》 北大核心 2025年第1期75-88,共14页
针对视频输入的单人三维人体姿态估计中表征不精确、融合不充分、结果不平滑的问题,提出三维人体姿态估计的多尺度时空特征融合方法.首先在空域定义关节点、肢体和上/下身人体标记并通过位置嵌入表示人体的空间多尺度特征;然后结合自注... 针对视频输入的单人三维人体姿态估计中表征不精确、融合不充分、结果不平滑的问题,提出三维人体姿态估计的多尺度时空特征融合方法.首先在空域定义关节点、肢体和上/下身人体标记并通过位置嵌入表示人体的空间多尺度特征;然后结合自注意力机制和多层感知机构建空间多尺度特征融合模块,融合关节点、肢体和上/下身三个空间多尺度特征,得到初步姿态特征序列;最后建立时序多尺度编码进行时序特征融合获得最终姿态特征序列,并通过时序解码,优化生成细化的三维人体姿态.在Human3.6M数据集上的实验结果表明,所提方法的平均每关节位置P-MPJPE和速度误差MPJVE分别为33.6和2.4,较对比方法降低了2.3%和4.0%,能够降低计算复杂度,提高三维人体姿态估计精度,生成准确、平滑的三维人体姿态估计结果.此外,在HumanEva-I数据集的测试结果表明,所提方法也具有一定的泛化性. 展开更多
关键词 三维人体姿态估计 多尺度特征 自注意力机制 时空特征融合 时序编码
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基于无人机影像的改进YOLOv5道路目标检测 被引量:3
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作者 马荣贵 张翼 董世浩 《无线电工程》 2025年第1期1-10,共10页
针对无人机影像中道路小目标漏检和目标之间遮挡导致的目标检测精度低、鲁棒性差等问题,提出一种多尺度的道路目标检测算法——YOLOv5-FTCE。执行多尺度的目标定位改进,采用完全交并比(Complete Intersection over Union,CIoU)边界框损... 针对无人机影像中道路小目标漏检和目标之间遮挡导致的目标检测精度低、鲁棒性差等问题,提出一种多尺度的道路目标检测算法——YOLOv5-FTCE。执行多尺度的目标定位改进,采用完全交并比(Complete Intersection over Union,CIoU)边界框损失,通过K-means算法对先验框进行重聚类,调整先验框的锚框参数并增加一个针对小目标的YOLO检测头;引入Transformer encoder结构融入C3模块改进Backbone网络,增强网络对不同局部信息的捕获能力;选用基于特征重组的Content-Aware ReAssembly of FEatures(CARAFE)模块进行上采样,提高上采样性能的同时减少特征处理过程中的信息损失;引入高效注意力模块(Efficient Attention Module,EAM)融合空间和通道信息,对网络中重要的信息进行增强。结果表明,YOLOv5-FTCE算法在VisDrone数据集上,检测精确率相比原始算法提高了9.5%,mAP50提高了8.9%,优于YOLOv7等其他常见的算法,有效改善了道路小目标和遮挡目标的漏检现象。 展开更多
关键词 道路目标检测 YOLOv5 Transformer编码器 特征重组 高效卷积注意力模块
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不均衡少标签样本下基于语义自动编码网络的高光谱图像分类
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作者 孙宝刚 何国斌 《红外技术》 北大核心 2025年第4期429-436,共8页
为了提升不均衡少标签样本下高光谱图像分类性能,本文提出了一种改进的语义自动编码网络,该网络首先将高光谱的类别标签信息引入到语义自编码网络模型中,通过将不同数据集的原始数据及标签信息分别映射至同一特征空间以建立已知类别和... 为了提升不均衡少标签样本下高光谱图像分类性能,本文提出了一种改进的语义自动编码网络,该网络首先将高光谱的类别标签信息引入到语义自编码网络模型中,通过将不同数据集的原始数据及标签信息分别映射至同一特征空间以建立已知类别和未知类别的关联,然后将该对应关系应用于未知数据集进行标签推理,并构建基于图正则化项的目标函数以保存数据集中特征流形结构,最后采用交替方向乘子法将全局问题分解为多个较小、较容易求解的局部子问题,最终获得全局最优解。实验选取3个具有不同的光谱维度、光谱带数量和土地覆盖类型的高光谱数据集进行处理,可以满足实验数据的多样性。结果表明,本文所提方法的分类结果具有较高的分类精度,其分类结果与基准结果比较相近,适合工程上对非均衡高光谱图像数据分类。 展开更多
关键词 高光谱图像 地物分类 深度学习 语义自动编码网络 语义关联 特征映射
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融合属性编码与集成学习的混合推荐算法
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作者 邱宁佳 董伟杰 《计算机工程与设计》 北大核心 2025年第2期508-514,共7页
为解决传统推荐算法对用户与物品的基础属性信息利用不充分,以及使用单一推荐算法导致推荐模型表达能力不足的问题。提出一种融合属性编码与集成学习的混合推荐算法。利用轻量的梯度提升机算法对用户与物品的基本属性信息进行融合编码处... 为解决传统推荐算法对用户与物品的基础属性信息利用不充分,以及使用单一推荐算法导致推荐模型表达能力不足的问题。提出一种融合属性编码与集成学习的混合推荐算法。利用轻量的梯度提升机算法对用户与物品的基本属性信息进行融合编码处理,丰富数据特征多样性;将线性算法与非线性算法混合作为基本模型,采用袋装的方式进行集成,提高算法模型推荐效果。实验结果表明,该混合推荐算法在多个评估标准上相比传统算法均有改善和提升。 展开更多
关键词 混合推荐算法 集成学习 特征编码 特征融合 特征剪枝 自助采样 并行训练
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基于单目RGB图像的三维手部姿态估计方法
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作者 杨冰 徐楚阳 +1 位作者 姚金良 向学勤 《浙江大学学报(工学版)》 北大核心 2025年第1期18-26,共9页
现有的三维手部姿态估计方法大多基于Transformer技术,未充分利用高分辨率下的局部空间信息,为此提出基于改进FastMETRO的三维手部姿态估计方法.引入可变形注意力机制,使得编码器的设计不再受限于图像特征序列长度;引入交错更新多尺度... 现有的三维手部姿态估计方法大多基于Transformer技术,未充分利用高分辨率下的局部空间信息,为此提出基于改进FastMETRO的三维手部姿态估计方法.引入可变形注意力机制,使得编码器的设计不再受限于图像特征序列长度;引入交错更新多尺度特征编码器来融合多尺度特征,强化生成手部姿态;引入图卷积残差模块来挖掘网格顶点间的显式语义联系.为了验证所提方法的有效性,在数据集FreiHAND、HO3D V2和HO3D V3上开展训练及评估实验.结果表明,所提方法的回归精度优于现有先进方法,在FreiHAND、HO3D V2、HO3D V3上的普鲁克对齐-平均关节点误差分别为5.8、10.0、10.5 mm. 展开更多
关键词 三维手部姿态估计 TRANSFORMER 可变形注意力机制 交错更新多尺度特征编码器 神经网络
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多尺度融合增强与注意力机制结合的图像语义分割
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作者 刘书刚 杜昊东 王洪涛 《计算机应用与软件》 北大核心 2025年第6期225-233,278,共10页
针对当前图像语义分割中分割效率不高与分割边界不连续问题,提出一种多尺度融合增强与注意力机制结合的语义分割算法。该算法对原有DeepLabv3+网络结构进行改进,在编码器部分提出一种特征提取增强网络结构,充分利用相邻层各个尺度的特... 针对当前图像语义分割中分割效率不高与分割边界不连续问题,提出一种多尺度融合增强与注意力机制结合的语义分割算法。该算法对原有DeepLabv3+网络结构进行改进,在编码器部分提出一种特征提取增强网络结构,充分利用相邻层各个尺度的特征信息进行融合,在解码器末端使用改进的轻量化卷积注意力模块,使得对于物体边界分割更加充分。通过在Pascal VOC2007和Cityscapes数据集上进行实验验证,结果表明该方法较原有网络的精确度有显著的提高。 展开更多
关键词 语义分割 特征融合增强 注意力模块 编码器 上采样
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基于改进柱形特征编码的单阶段目标检测算法
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作者 罗玉涛 毛浩杰 《华南理工大学学报(自然科学版)》 北大核心 2025年第3期1-11,共11页
基于柱形(Pillar)的单阶段点云3维目标检测算法凭借其较高的运行效率,在工业界得到了广泛的关注和应用。但对点云柱形量化造成的点云3维特征细粒度信息损失,导致这类算法对稀疏点云小目标的检测能力较弱。尽管部分研究对此问题提出了应... 基于柱形(Pillar)的单阶段点云3维目标检测算法凭借其较高的运行效率,在工业界得到了广泛的关注和应用。但对点云柱形量化造成的点云3维特征细粒度信息损失,导致这类算法对稀疏点云小目标的检测能力较弱。尽管部分研究对此问题提出了应对方法,但通常以较高的检测时间成本或者大目标检测精度作为代价。为此,该文提出了一种基于改进柱形特征编码的柱形点云目标检测算法。首先,构建可实现柱形单元内部点云局部与全局特征相结合的柱形特征编码网络,用于增强柱形量化特征的表征能力;然后,设计一个由2维稀疏卷积块与特征融合网络相结合的主干网络,用于融合多尺度的高级抽象语义特征和低级细粒度空间特征,防止过度关注小尺寸特征而降低大目标的检测性能;最后,在KITTI自动驾驶数据集上进行训练和测试,并对实验结果进行了可视化和消融研究。结果显示:所提算法在KITTI数据集的中等难度下,多个类别的平均精度均值达63.54%、平均方向相似性均值达70.72%,平均检测帧速率达31.5 f/s;与PointPillars、TANet和PiFEnet算法相比,该文算法的平均精度均值分别提高了2.44、2.05和2.38个百分点,平均方向相似性均值分别提高了4.69、0.68和7.83个百分点,在同类算法的对比中表现出工程应用潜力。 展开更多
关键词 智能汽车 3维目标检测 点云 柱形特征编码
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一种自适应残差卷积自编码网络及其故障诊断应用
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作者 潘天成 陈龙 +1 位作者 蒲春雷 陈志强 《机电工程》 北大核心 2025年第3期529-538,共10页
针对传统卷积自编码器(CAE)会将不同故障产生的相似信号进行相同的非线性变换,导致故障诊断准确率下降的问题,提出了一种自适应残差卷积自编码网络(ARCAE),并将其应用于滚动轴承故障诊断中。首先,在残差模块的基础上,引入了自适应参数... 针对传统卷积自编码器(CAE)会将不同故障产生的相似信号进行相同的非线性变换,导致故障诊断准确率下降的问题,提出了一种自适应残差卷积自编码网络(ARCAE),并将其应用于滚动轴承故障诊断中。首先,在残差模块的基础上,引入了自适应参数化修正线性单元(APReLU),建立了自适应残差模块(ARM),ARM可以对相似的输入特征进行自适应非线性变换,避免了特征的错误识别;其次,在CAE中嵌入多级ARM,构建了ARCAE,增加了CAE的深度,提取了更具鉴别性的深层次特征,同时有效防止了网络加深而造成的性能退化;最后,基于ARCAE建立了针对一维信号的故障诊断新方法,将其应用于无监督滚动轴承故障诊断中,并通过两个不同类型的实验,对上述方法的有效性进行了验证。研究结果表明:在恒定转速工况下,ARCAE的诊断准确率最高,平均准确率达到了97.05%,且标准差仅为0.007,远低于其他几种传统CAE网络;在变转速工况下,ARCAE模型诊断准确率仍然是最高的,平均准确率达到了93.25%,由此说明ARCAE具有较高的特征提取能力和分类准确率;此外,变转速工况下,由于转速变化导致不同状态的振动信号特征差异变大,诊断难度加大,但与其他几种传统CAE网络相比,ARCAE诊断准确率下降最少,仅为5.37%,说明ARCAE具有更强的鲁棒性和稳定性。 展开更多
关键词 滚动轴承 自适应残差卷积自编码网络 自适应参数化修正线性单元 自适应残差模块 无监督故障诊断 特征提取
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