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Dynamic Multi-Graph Spatio-Temporal Graph Traffic Flow Prediction in Bangkok:An Application of a Continuous Convolutional Neural Network
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作者 Pongsakon Promsawat Weerapan Sae-dan +2 位作者 Marisa Kaewsuwan Weerawat Sudsutad Aphirak Aphithana 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期579-607,共29页
The ability to accurately predict urban traffic flows is crucial for optimising city operations.Consequently,various methods for forecasting urban traffic have been developed,focusing on analysing historical data to u... The ability to accurately predict urban traffic flows is crucial for optimising city operations.Consequently,various methods for forecasting urban traffic have been developed,focusing on analysing historical data to understand complex mobility patterns.Deep learning techniques,such as graph neural networks(GNNs),are popular for their ability to capture spatio-temporal dependencies.However,these models often become overly complex due to the large number of hyper-parameters involved.In this study,we introduce Dynamic Multi-Graph Spatial-Temporal Graph Neural Ordinary Differential Equation Networks(DMST-GNODE),a framework based on ordinary differential equations(ODEs)that autonomously discovers effective spatial-temporal graph neural network(STGNN)architectures for traffic prediction tasks.The comparative analysis of DMST-GNODE and baseline models indicates that DMST-GNODE model demonstrates superior performance across multiple datasets,consistently achieving the lowest Root Mean Square Error(RMSE)and Mean Absolute Error(MAE)values,alongside the highest accuracy.On the BKK(Bangkok)dataset,it outperformed other models with an RMSE of 3.3165 and an accuracy of 0.9367 for a 20-min interval,maintaining this trend across 40 and 60 min.Similarly,on the PeMS08 dataset,DMST-GNODE achieved the best performance with an RMSE of 19.4863 and an accuracy of 0.9377 at 20 min,demonstrating its effectiveness over longer periods.The Los_Loop dataset results further emphasise this model’s advantage,with an RMSE of 3.3422 and an accuracy of 0.7643 at 20 min,consistently maintaining superiority across all time intervals.These numerical highlights indicate that DMST-GNODE not only outperforms baseline models but also achieves higher accuracy and lower errors across different time intervals and datasets. 展开更多
关键词 Graph neural networks convolutional neural network deep learning dynamic multi-graph SPATIO-TEMPORAL
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Omni-dimensional dynamic convolution feature coordinate attention network for pneumonia classification
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作者 Yufei Li Yufei Xin +5 位作者 Xinni Li Yinrui Zhang Cheng Liu Zhengwen Cao Shaoyi Du Lin Wang 《Visual Computing for Industry,Biomedicine,and Art》 2024年第1期196-208,共13页
Pneumonia is a serious disease that can be fatal,particularly among children and the elderly.The accuracy of pneumonia diagnosis can be improved by combining artificial-intelligence technology with X-ray imaging.This ... Pneumonia is a serious disease that can be fatal,particularly among children and the elderly.The accuracy of pneumonia diagnosis can be improved by combining artificial-intelligence technology with X-ray imaging.This study proposes X-ODFCANet,which addresses the issues of low accuracy and excessive parameters in existing deep-learningbased pneumonia-classification methods.This network incorporates a feature coordination attention module and an omni-dimensional dynamic convolution(ODConv)module,leveraging the residual module for feature extraction from X-ray images.The feature coordination attention module utilizes two one-dimensional feature encoding processes to aggregate feature information from different spatial directions.Additionally,the ODConv module extracts and fuses feature information in four dimensions:the spatial dimension of the convolution kernel,input and output channel quantities,and convolution kernel quantity.The experimental results demonstrate that the proposed method can effectively improve the accuracy of pneumonia classification,which is 3.77%higher than that of ResNet18.The model parameters are 4.45M,which was reduced by approximately 2.5 times.The code is available at https://github.com/limuni/X ODFCA NET. 展开更多
关键词 PNEUMONIA Coordinate attention dynamic convolution ResNet18 X-ODFCANet
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Multiphase convolutional dense network for the classification of focal liver lesions on dynamic contrast-enhanced computed tomography 被引量:5
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作者 Su-E Cao Lin-Qi Zhang +10 位作者 Si-Chi Kuang Wen-Qi Shi Bing Hu Si-Dong Xie Yi-Nan Chen Hui Liu Si-Min Chen Ting Jiang Meng Ye Han-Xi Zhang Jin Wang 《World Journal of Gastroenterology》 SCIE CAS 2020年第25期3660-3672,共13页
BACKGROUND The accurate classification of focal liver lesions(FLLs)is essential to properly guide treatment options and predict prognosis.Dynamic contrast-enhanced computed tomography(DCE-CT)is still the cornerstone i... BACKGROUND The accurate classification of focal liver lesions(FLLs)is essential to properly guide treatment options and predict prognosis.Dynamic contrast-enhanced computed tomography(DCE-CT)is still the cornerstone in the exact classification of FLLs due to its noninvasive nature,high scanning speed,and high-density resolution.Since their recent development,convolutional neural network-based deep learning techniques has been recognized to have high potential for image recognition tasks.AIM To develop and evaluate an automated multiphase convolutional dense network(MP-CDN)to classify FLLs on multiphase CT.METHODS A total of 517 FLLs scanned on a 320-detector CT scanner using a four-phase DCECT imaging protocol(including precontrast phase,arterial phase,portal venous phase,and delayed phase)from 2012 to 2017 were retrospectively enrolled.FLLs were classified into four categories:Category A,hepatocellular carcinoma(HCC);category B,liver metastases;category C,benign non-inflammatory FLLs including hemangiomas,focal nodular hyperplasias and adenomas;and category D,hepatic abscesses.Each category was split into a training set and test set in an approximate 8:2 ratio.An MP-CDN classifier with a sequential input of the fourphase CT images was developed to automatically classify FLLs.The classification performance of the model was evaluated on the test set;the accuracy and specificity were calculated from the confusion matrix,and the area under the receiver operating characteristic curve(AUC)was calculated from the SoftMax probability outputted from the last layer of the MP-CDN.RESULTS A total of 410 FLLs were used for training and 107 FLLs were used for testing.The mean classification accuracy of the test set was 81.3%(87/107).The accuracy/specificity of distinguishing each category from the others were 0.916/0.964,0.925/0.905,0.860/0.918,and 0.925/0.963 for HCC,metastases,benign non-inflammatory FLLs,and abscesses on the test set,respectively.The AUC(95%confidence interval)for differentiating each category from the others was 0.92(0.837-0.992),0.99(0.967-1.00),0.88(0.795-0.955)and 0.96(0.914-0.996)for HCC,metastases,benign non-inflammatory FLLs,and abscesses on the test set,respectively.CONCLUSION MP-CDN accurately classified FLLs detected on four-phase CT as HCC,metastases,benign non-inflammatory FLLs and hepatic abscesses and may assist radiologists in identifying the different types of FLLs. 展开更多
关键词 Deep learning convolutional neural networks Focal liver lesions CLASSIFICATION Multiphase computed tomography dynamic enhancement pattern
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Graph Convolutional Networks Embedding Textual Structure Information for Relation Extraction
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作者 Chuyuan Wei Jinzhe Li +2 位作者 Zhiyuan Wang Shanshan Wan Maozu Guo 《Computers, Materials & Continua》 SCIE EI 2024年第5期3299-3314,共16页
Deep neural network-based relational extraction research has made significant progress in recent years,andit provides data support for many natural language processing downstream tasks such as building knowledgegraph,... Deep neural network-based relational extraction research has made significant progress in recent years,andit provides data support for many natural language processing downstream tasks such as building knowledgegraph,sentiment analysis and question-answering systems.However,previous studies ignored much unusedstructural information in sentences that could enhance the performance of the relation extraction task.Moreover,most existing dependency-based models utilize self-attention to distinguish the importance of context,whichhardly deals withmultiple-structure information.To efficiently leverage multiple structure information,this paperproposes a dynamic structure attention mechanism model based on textual structure information,which deeplyintegrates word embedding,named entity recognition labels,part of speech,dependency tree and dependency typeinto a graph convolutional network.Specifically,our model extracts text features of different structures from theinput sentence.Textual Structure information Graph Convolutional Networks employs the dynamic structureattention mechanism to learn multi-structure attention,effectively distinguishing important contextual features invarious structural information.In addition,multi-structure weights are carefully designed as amergingmechanismin the different structure attention to dynamically adjust the final attention.This paper combines these featuresand trains a graph convolutional network for relation extraction.We experiment on supervised relation extractiondatasets including SemEval 2010 Task 8,TACRED,TACREV,and Re-TACED,the result significantly outperformsthe previous. 展开更多
关键词 Relation extraction graph convolutional neural networks dependency tree dynamic structure attention
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D^(2)-GCN:a graph convolutional network with dynamic disentanglement for node classification
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作者 Shangwei WU Yingtong XIONG +1 位作者 Hui LIANG Chuliang WENG 《Frontiers of Computer Science》 2025年第1期145-161,共17页
Classic Graph Convolutional Networks (GCNs) often learn node representation holistically, which ignores the distinct impacts from different neighbors when aggregating their features to update a node’s representation.... Classic Graph Convolutional Networks (GCNs) often learn node representation holistically, which ignores the distinct impacts from different neighbors when aggregating their features to update a node’s representation. Disentangled GCNs have been proposed to divide each node’s representation into several feature units. However, current disentangling methods do not try to figure out how many inherent factors the model should assign to help extract the best representation of each node. This paper then proposes D^(2)-GCN to provide dynamic disentanglement in GCNs and present the most appropriate factorization of each node’s mixed features. The convergence of the proposed method is proved both theoretically and experimentally. Experiments on real-world datasets show that D^(2)-GCN outperforms the baseline models concerning node classification results in both single- and multi-label tasks. 展开更多
关键词 graph convolutional networks dynamic disentanglement label entropy node classification
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EFFICIENT NUMERICAL METHOD FOR DYNAMIC ANALYSIS OF FLEXIBLE ROD HIT BY RIGID BALL 被引量:1
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作者 徐春铃 王鑫伟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期338-344,共7页
Impact dynamics of flexible solids is important in engineering practice. Obtaining its dynamic response is a challenging task and usually achieved by numerical methods. The objectives of the study are twofold. Firstly... Impact dynamics of flexible solids is important in engineering practice. Obtaining its dynamic response is a challenging task and usually achieved by numerical methods. The objectives of the study are twofold. Firstly, the discrete singular convolution (DSC) is used for the first time to analyze the impact dynamics. Secondly, the efficiency of various numerical methods for dynamic analysis is explored via an example of a flexible rod hit by a rigid ball. Three numerical methods, including the conventional finite element (FE) method, the DSC algorithm, and the spectral finite element (SFE) method, and one proposed modeling strategy, the improved spectral finite element (ISFE) method, are involved. Numerical results are compared with the known analytical solutions to show their efficiency. It is demonstrated that the proposed ISFE modeling strategy with a proper length of con- ventional FE yields the most accurate contact stress among the four investigated models. It is also found that the DSC algorithm is an alternative method for collision problems. 展开更多
关键词 impact dynamics finite element method discrete singular convolution algorithm spectral finite ele- ment method
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Dynamic Differential Current-based Transformer Protection Using a Convolutional Neural Network
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作者 Zongbo Li Zaibin Jiao Anyang He 《CSEE Journal of Power and Energy Systems》 2025年第2期871-885,共15页
A reliable transformer protection method is crucial for power systems. Aiming at improving the generalization performance and response speed of multi-feature fusion based transformer protection, this paper presents a ... A reliable transformer protection method is crucial for power systems. Aiming at improving the generalization performance and response speed of multi-feature fusion based transformer protection, this paper presents a dynamic differential current by fusing pre-disturbance and post-disturbance differential currents in real time then developing a dynamic differential current based transformer protection focusing on the feature changes of differential current. Generally, the image of differential current can comprehensively embody the feature changes resulting from any disturbance. In addition, a short window is sometimes sufficient to clearly reflect the internal fault because the differential current will instantly change when an internal fault occurs. Therefore, in order to identify the running states reliably in the shortest possible time, multiple images, including the differential current from a pre-disturbance one cycle to a post-disturbance different time, are combined by time order to define a dynamic differential current. After the protection method is started, this dynamic differential current serves as input for the deep learning algorithm to identify the running states in real time. Once the transformer is identified as a faulty one, a tripping signal is issued and the protection method stops. The dynamic model experiments show that the proposed protection method has a strong generalization ability and rapid response speed. 展开更多
关键词 convolutional neural network dynamic differential current dynamic model experiments feature changes image transformer protection
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On the convergence and causality of a frequency domain method for dynamic structural analysis
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作者 Kuifu Chen Senwen Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第2期162-169,共8页
Venanico-Filho et al. developed an elegant matrix formulation for dynamic analysis by frequency domain (FD), but the convergence, causality and extended period need further refining. In the present paper, it was arg... Venanico-Filho et al. developed an elegant matrix formulation for dynamic analysis by frequency domain (FD), but the convergence, causality and extended period need further refining. In the present paper, it was argued that: (1) under reasonable assumptions (approximating the frequency response function by the discrete Fourier transform of the discretized unitary impulse response function), the matrix formulation by FD is equivalent to a circular convolution; (2) to avoid the wraparound interference, the excitation vector and impulse response must be padded with enough zeros; (3) provided that the zero padding requirement satisfied, the convergence and accuracy of direct time domain analysis, which is equivalent to that by FD, are guaranteed by the numerical integration scheme; (4) the imaginary part of the computational response approaching zero is due to the continuity of the impulse response functions. 展开更多
关键词 Time domain Fourier transforms Causality dynamic responses convolution
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A New Speech Encoder Based on Dynamic Framing Approach
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作者 Renyuan Liu Jian Yang +1 位作者 Xiaobing Zhou Xiaoguang Yue 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1259-1276,共18页
Latent information is difficult to get from the text in speech synthesis.Studies show that features from speech can get more information to help text encoding.In the field of speech encoding,a lot of work has been con... Latent information is difficult to get from the text in speech synthesis.Studies show that features from speech can get more information to help text encoding.In the field of speech encoding,a lot of work has been conducted on two aspects.The first aspect is to encode speech frame by frame.The second aspect is to encode the whole speech to a vector.But the scale in these aspects is fixed.So,encoding speech with an adjustable scale for more latent information is worthy of investigation.But current alignment approaches only support frame-by-frame encoding and speech-to-vector encoding.It remains a challenge to propose a new alignment approach to support adjustable scale speech encoding.This paper presents the dynamic speech encoder with a new alignment approach in conjunction with frame-by-frame encoding and speech-to-vector encoding.The speech feature fromourmodel achieves three functions.First,the speech feature can reconstruct the origin speech while the length of the speech feature is equal to the text length.Second,our model can get text embedding fromspeech,and the encoded speech feature is similar to the text embedding result.Finally,it can transfer the style of synthesis speech and make it more similar to the given reference speech. 展开更多
关键词 Speech synthesis dynamic framing convolution network speech encoding
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Use of Local Region Maps on Convolutional LSTM for Single-Image HDR Reconstruction
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作者 Seungwook Oh GyeongIk Shin Hyunki Hong 《Computers, Materials & Continua》 SCIE EI 2022年第6期4555-4572,共18页
Low dynamic range(LDR)images captured by consumer cameras have a limited luminance range.As the conventional method for generating high dynamic range(HDR)images involves merging multiple-exposure LDR images of the sam... Low dynamic range(LDR)images captured by consumer cameras have a limited luminance range.As the conventional method for generating high dynamic range(HDR)images involves merging multiple-exposure LDR images of the same scene(assuming a stationary scene),we introduce a learning-based model for single-image HDR reconstruction.An input LDR image is sequentially segmented into the local region maps based on the cumulative histogram of the input brightness distribution.Using the local region maps,SParam-Net estimates the parameters of an inverse tone mapping function to generate a pseudo-HDR image.We process the segmented region maps as the input sequences on long short-term memory.Finally,a fast super-resolution convolutional neural network is used for HDR image reconstruction.The proposed method was trained and tested on datasets including HDR-Real,LDR-HDR-pair,and HDR-Eye.The experimental results revealed that HDR images can be generated more reliably than using contemporary end-to-end approaches. 展开更多
关键词 Low dynamic range high dynamic range deep learning convolutional long short-term memory inverse tone mapping function
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Deep Learning Convolutional Neural Network for ECG Signal Classification Aggregated Using IoT
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作者 S.Karthiga A.M.Abirami 《Computer Systems Science & Engineering》 SCIE EI 2022年第9期851-866,共16页
Much attention has been given to the Internet of Things (IoT) by citizens, industries, governments, and universities for applications like smart buildings, environmental monitoring, health care and so on. With IoT, ne... Much attention has been given to the Internet of Things (IoT) by citizens, industries, governments, and universities for applications like smart buildings, environmental monitoring, health care and so on. With IoT, networkconnectivity is facilitated between smart devices from anyplace and anytime.IoT-based health monitoring systems are gaining popularity and acceptance forcontinuous monitoring and detect health abnormalities from the data collected.Electrocardiographic (ECG) signals are widely used for heart diseases detection.A novel method has been proposed in this work for ECG monitoring using IoTtechniques. In this work, a two-stage approach is employed. In the first stage, arouting protocol based on Dynamic Source Routing (DSR) and Routing byEnergy and Link quality (REL) for IoT healthcare platform is proposed for effi-cient data collection, and in the second stage, classification of ECG for Arrhythmia. Furthermore, this work has evaluated Support Vector Machine (SVM),Artificial Neural Network (ANN), and Convolution Neural Networks (CNNs)-based approach for ECG signals classification. Deep-ECG will use a deep CNNto extract critical features and then compare through evaluation of simple and fastdistance functions in order to obtain an efficient classification of heart abnormalities. For the identification of abnormal data, this work has proposed techniquesfor the classification of ECG data, which has been obtained from mobile watchusers. For experimental verification of the proposed methods, the Beth Israel Hospital (MIT/BIH) Arrhythmia and Massachusetts Institute of Technology (MIT)Database was used for evaluation. Results confirm the presented method’s superior performance with regards to the accuracy of classification. The CNN achievedan accuracy of 91.92% and has a higher accuracy of 4.98% for the SVM and2.68% for the ANN. 展开更多
关键词 Internet of things electrocardiographic signals dynamic source routing routing by energy and link quality convolution neural networks
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A performance prediction method for on-site chillers based on dynamic graph convolutional network enhanced by association rules
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作者 Qiao Deng Zhiwen Chen +3 位作者 Wanting Zhu Zefan Li Yifeng Yuan Weihua Gui 《Building Simulation》 SCIE EI CSCD 2024年第7期1213-1229,共17页
Accurately predicting the chiller coefficient of performance(COP)is essential for improving the energy efficiency of heating,ventilation,and air conditioning(HVAC)systems,significantly contributing to energy conservat... Accurately predicting the chiller coefficient of performance(COP)is essential for improving the energy efficiency of heating,ventilation,and air conditioning(HVAC)systems,significantly contributing to energy conservation in buildings.Traditional performance prediction methods often overlook the dynamic interaction among sensor variables and face challenges in using extensive historical data efficiently,which impedes accurate predictions.To overcome these challenges,this paper proposes an innovative on-site chiller performance prediction method employing a dynamic graph convolutional network(GCN)enhanced by association rules.The distinctive feature of this method is constructing an association graph bank containing static graphs in each operating mode by mining the association rules between various sensor variables in historical operating data.A real-time graph is created by analyzing the correlation between various sensor variables in the current operating data.This graph is fused online with the static graph in the current operating mode to obtain a dynamic graph used for feature extraction and training of GCN.The effectiveness of this method has been empirically confirmed through the operational data of an actual building chiller system.Comparative analysis with state-of-the-art methods highlights the superior performance of the proposed method. 展开更多
关键词 chillers performance prediction dynamic graph convolutional network association rules operating modes
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融合混合空洞卷积和动态卷积的敦煌壁画修复
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作者 刘仲民 李耀龙 胡文瑾 《计算机工程与设计》 北大核心 2025年第2期595-602,共8页
为有效修复壁画破损区域的语义信息、解决壁画深层特征信息提取不足导致的修复伪影以及修复失真等问题,提出一种融合混合空洞卷积与动态卷积的敦煌壁画修复模型。针对修复伪影问题,在模型编码阶段设计一种混合残差模块;针对修复失真问题... 为有效修复壁画破损区域的语义信息、解决壁画深层特征信息提取不足导致的修复伪影以及修复失真等问题,提出一种融合混合空洞卷积与动态卷积的敦煌壁画修复模型。针对修复伪影问题,在模型编码阶段设计一种混合残差模块;针对修复失真问题,通过在动态核预测分支和动态语义及图像滤波分支中加入动态卷积来提高网络的预测和滤波性能。实验结果表明,所提模型具有更高的评价指标,且视觉效果上具有更细致的纹理,语义信息更丰富,边缘结构更连贯。 展开更多
关键词 信息处理技术 壁画修复 混合空洞卷积 动态卷积 图像滤波 残差网络 深度学习
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基于多尺度动态卷积和GRU的轴承故障诊断
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作者 董绍江 彭银山 +1 位作者 邹松 黄翔 《组合机床与自动化加工技术》 北大核心 2025年第3期150-154,共5页
针对传统轴承故障诊断过程中忽略轴承振动信号的关联时间维度信息的问题,提出了基于多尺度动态扩张卷积神经网络(MSDDCNN)和门控循环单元网络(GRU)的轴承故障诊断方法。首先利用不同尺寸宽卷积核从各个维度捕捉振动信号多维特征以增大... 针对传统轴承故障诊断过程中忽略轴承振动信号的关联时间维度信息的问题,提出了基于多尺度动态扩张卷积神经网络(MSDDCNN)和门控循环单元网络(GRU)的轴承故障诊断方法。首先利用不同尺寸宽卷积核从各个维度捕捉振动信号多维特征以增大感受野;其次引入动态加权层自适应选择卷积核尺度的大小并自动地给予特征序列中的不同部分不同的权重,更加充分提升特征表示的能力;最后利用门控循环单元充分提取振动信号中不同尺度的时序特征,以加强各个维度间前后时间维度关联信息。实验结果表明,所提方法在PU和JNU公开数据集上平均准确率分别为98.79%和98.65%。为验证所提网络模型诊断有效性,所提方法在某公司自制的轴承故障数据集(CME)也表现出较高的准确率和较大抗噪声能力,为有效诊断旋转部件故障提供了实际依据。 展开更多
关键词 多尺度 动态卷积 扩张卷积 GRU 故障诊断
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改进抗噪1D-CNN的旋转车轮动平衡状态监测
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作者 周海超 关浩东 +2 位作者 王国林 张宇 赵春来 《振动.测试与诊断》 北大核心 2025年第2期309-315,412,413,共9页
针对实车旋转车轮动平衡状态难以实时监测及预判的问题,提出了一种融合注意力机制的抗噪一维卷积神经网络(noise resistant 1D convolutional neural network,简称NRCNN)的旋转车轮动平衡健康状态监测方法。首先,构建NRCNN模型,以在实... 针对实车旋转车轮动平衡状态难以实时监测及预判的问题,提出了一种融合注意力机制的抗噪一维卷积神经网络(noise resistant 1D convolutional neural network,简称NRCNN)的旋转车轮动平衡健康状态监测方法。首先,构建NRCNN模型,以在实车车轮上添加3种不同质量平衡块的方式获得3种不同速度下对应的旋转车轮动不平衡状态下的振动信息;其次,以高斯白噪声为噪声输入,对所测旋转车轮不同动平衡状态的振动信息进行处理,获得试验样本数据,并用其进行模型训练;然后,综合运用卷积运算机制和特征变换进行t分布随机邻域嵌入(t-distributed stochastic neighbor embedding,简称t-SNE)可视化显示,实现对不同动平衡状态的分类输出。结果表明,在不同信噪比的工况下,所提出的改进NRCNN模型旋转车轮的动平衡状态监测方法相比于传统一维卷积神经网络(1D convolutional neural network,简称1D-CNN)模型,展现出更高的诊断准确性,最高可达到99.95%。 展开更多
关键词 卷积神经网络 注意力机制 车轮动平衡 状态监测 高斯白噪声
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融合大卷积核的风电锚栓裂纹检测
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作者 孙前来 荆佳鹏 +2 位作者 张帅 胡啸 刘瑞珍 《制造业自动化》 2025年第3期142-148,共7页
风电锚栓在加工过程中通常会产生表面裂纹等缺陷,针对锚栓表面细长裂纹检测效率低、精度差的问题,提出了一种融合大卷积核的YOLOv5s网络。首先,在特征提取网络中融合大卷积核,来获得更大的有效感受野、提取更多的空间信息。其次,引入单... 风电锚栓在加工过程中通常会产生表面裂纹等缺陷,针对锚栓表面细长裂纹检测效率低、精度差的问题,提出了一种融合大卷积核的YOLOv5s网络。首先,在特征提取网络中融合大卷积核,来获得更大的有效感受野、提取更多的空间信息。其次,引入单卷积核的全维动态卷积,采用并行策略,同时学习四个不同维度的特征,不仅减少了计算量,而且提高了特征提取能力。最后添加协调注意力机制,增强对位置信息的提取能力。实验结果表明,该算法较原YOLOv5s模型在风电锚栓裂纹数据集上mAP提高了3%,FLOPs减少了21.5%,FPS达到了85帧/秒。可以满足工业生产的实时性、准确性要求。 展开更多
关键词 Yolov5s 锚栓裂纹检测 全维动态卷积 大卷积核
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基于改进YOLOv8n的雨天场景中飞机铆钉检测方法
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作者 夏正洪 杨磊 +2 位作者 刘璐 何琥 钟吉飞 《中国安全生产科学技术》 北大核心 2025年第1期195-201,共7页
为解决雨天场景中飞机表面附着与铆钉大小、形状相似的水滴而导致机务工程师在绕机检查过程中易出现铆钉误检的问题,提出1种基于改进YOLOv8n的飞机铆钉小目标检测方法。首先,改进C2f层,融入动态蛇形卷积,以捕捉复杂多变的全局形态特征;... 为解决雨天场景中飞机表面附着与铆钉大小、形状相似的水滴而导致机务工程师在绕机检查过程中易出现铆钉误检的问题,提出1种基于改进YOLOv8n的飞机铆钉小目标检测方法。首先,改进C2f层,融入动态蛇形卷积,以捕捉复杂多变的全局形态特征;其次,在主干网络中嵌入可变形注意力机制,自适应调整对不同区域的关注度;然后,增加1个160×160的小目标检测层,提高小目标的检测能力;最后,使用斯库拉交并比(SIoU)边界框损失函数,提升模型训练速度和推理准确性,基于自建的飞机铆钉和雨滴数据集进行消融实验和对比实验。研究结果表明:本文所提算法在雨天场景下的铆钉检测精确度、召回率、mAP值分别较YOLOv8n提升7.4,4.0,7.8百分点,较其他主流算法也有显著提升。研究结果可为特殊天气下的飞机铆钉检测提供理论基础。 展开更多
关键词 航空安全 小目标检测 飞机铆钉 动态蛇形卷积 可变形注意力机制
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基于CWT-IDenseNet的滚动轴承故障诊断方法
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作者 贾广飞 梁汉文 +2 位作者 杨金秋 武哲 韩雨欣 《河北科技大学学报》 北大核心 2025年第2期129-140,共12页
针对一维信号所含信息不全面和DenseNet网络在变工况下存在过拟合等问题,提出了基于连续小波变换时频图像和改进密集连接卷积网络(improved DenseNet,IDenseNet)的滚动轴承故障诊断方法CWT-IDenseNet。首先,将一维振动信号通过CWT转为... 针对一维信号所含信息不全面和DenseNet网络在变工况下存在过拟合等问题,提出了基于连续小波变换时频图像和改进密集连接卷积网络(improved DenseNet,IDenseNet)的滚动轴承故障诊断方法CWT-IDenseNet。首先,将一维振动信号通过CWT转为二维时频图像;其次,对DenseNet网络进行改进,将DenseNet第1个卷积块中的ReLU激活函数替换为Swish激活函数(Swish激活函数更平滑);同时,在网络中引入基于风格的卷积神经网络重校准模块(style-based recalibration module,SRM)和空间与通道注意力机制模块(convolutional block attention module,CBAM),SRM关注特征通道权重,CBAM则从通道和空间2个维度增强特征表达能力,进而得到IDenseNet;最后,将二维时频图像输入到IDenseNet模型中进行特征提取和故障诊断,通过模型的Softmax层输出故障诊断结果。结果表明,所提方法在恒定工况及变工况下的平均故障识别准确率均达到97.80%,且在迁移学习模型中,平均故障识别准确率达到了99.44%。CWT-IDenseNet方法可以有效提高模型的泛化能力,在恒定工况及变工况下具有显著优势,对提高滚动轴承故障诊断的准确率和可靠性具有参考价值。 展开更多
关键词 机械动力学与振动 滚动轴承故障诊断 连续小波变换 密集连接卷积网络 注意力机制
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基于深度学习的钻孔冲煤量智能识别方法
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作者 李小军 赵明炀 李淼 《煤田地质与勘探》 北大核心 2025年第1期257-270,共14页
【目的】为解决人工统计钻孔冲煤量不准确以及效率低等问题,提出一种YOLOv8n、Res-Net34和PP-OCRv4算法相结合的智能识别方法。【方法】该方法首先使用YOLOv8n算法完成一级检测,同时并行级联ResNet34算法与PP-OCRv4算法进行二级处理,并... 【目的】为解决人工统计钻孔冲煤量不准确以及效率低等问题,提出一种YOLOv8n、Res-Net34和PP-OCRv4算法相结合的智能识别方法。【方法】该方法首先使用YOLOv8n算法完成一级检测,同时并行级联ResNet34算法与PP-OCRv4算法进行二级处理,并结合基于追踪帧数的分类状态判别方法,建立了冲煤量自动计算的算法框架。其次,在YOLOv8n的C2f模块中引入可变形卷积DCNv2模块,以削弱点状强光照对特征采集的影响,并将其默认的检测头替换为Dynamic Head检测头模块,以强化算法在尺度,空间和通道维度的特征提取能力,以及将CIoU损失函数替换为SIoU损失函数,以加速预测框与真实框的匹配,并利用自建的数据集对改进后的YOLOv8n算法进行验证。【结果和结论】结果表明:(1)与原算法相比,平均类别检测精度提高了7.6%,召回率提高了3.5%,精确率提高了6.4%,验证了改进策略对提升模型性能的有效性和稳定性。(2)对4个不同的瓦斯抽采水力冲孔钻场的实时视频进行测试,识别准确率分别为100.0%、93.3%、95.7%和93.1%,平均达到95.5%,满足了水力冲孔钻孔冲煤量自动识别的精度要求。(3)采用追踪帧数确定ResNet34分类状态的方法,解决了分类状态单次识别结果不可靠的问题。研究成果为YOLO系列算法与其他深度学习技术的融合和广泛应用提供了技术与实践基础,对促进瓦斯抽采钻场等煤矿井下复杂场景的智能化进步具有参考价值。 展开更多
关键词 瓦斯抽采 冲煤量 YOLOv8n ResNet34 PaddleOCR 可变形卷积 动态检测头 智能识别 煤矿
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改进YOLOv8算法的机场外来物检测研究
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作者 郭九霞 李金润 +2 位作者 王义龙 李静远 唐锐 《舰船电子工程》 2025年第3期119-125,共7页
为解决机场外来物检测方法存在检测稳定性差、漏检的问题,论文使用YOLOv8算法进行改进。首先,使用动态卷积ODConv,通过引入可学习的形变模块,动态调整卷积核的形状、大小及通道维度,优化卷积过程并专注于机场外来物的形状大小和尺度变化... 为解决机场外来物检测方法存在检测稳定性差、漏检的问题,论文使用YOLOv8算法进行改进。首先,使用动态卷积ODConv,通过引入可学习的形变模块,动态调整卷积核的形状、大小及通道维度,优化卷积过程并专注于机场外来物的形状大小和尺度变化,实现对图像特征信息的高效提取;其次,设计了C2f_DAConv模块,降低了算法的参数量;然后,在PANet网络架构的基础上,融合主干网络的P2特征层,并将PANet网络架构更改为BiFPN,该网络实现了底层细节特征信息和高层语义特征信息的高效融合,减少了外来物目标特征的信息丢失;最后,为解决预测框与目标框之间的定位误差问题,更改损失函数为Inner SIoU,优化了算法的计算过程,加快了算法训练的收敛速度,同时提升了算法的检测精度。实验结果表明,改进的算法相比原YOLOv8算法,其参数量降低了35.5%,平均精度均值(mAP)达到97.3%,提升了2.0%,召回率(Re-call)为95.5%,提升了5.2%;对比分析F1曲线、P-R曲线和Recall曲线,表明改进的算法在检测稳定性方面有显著提升,能有效解决机场外来物的漏检问题。 展开更多
关键词 改进YOLOv8算法 FOD检测 动态卷积 机场安全
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