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Quantitative Detection of Micro Hole Wall Roughness in PCBs Based on Improved U-Net Model
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作者 Lijuan Zheng Yonghao Li +5 位作者 Zhuangzhuang Sun Yangquan Luo Ying Xu Jun Wang Chengyong Wang Xin Wei 《Chinese Journal of Mechanical Engineering》 2025年第3期1-11,共11页
The current method for inspecting microholes in printed circuit boards(PCBs)involves preparing slices followed by optical microscope measurements.However,this approach suffers from low detection efficiency,poor reliab... The current method for inspecting microholes in printed circuit boards(PCBs)involves preparing slices followed by optical microscope measurements.However,this approach suffers from low detection efficiency,poor reliability,and insufficient measurement stability.Micro-CT enables the observation of the internal structures of the sample without the need for slicing,thereby presenting a promising new method for assessing the quality of microholes in PCBs.This study integrates computer vision technology with computed tomography(CT)to propose a method for detecting microhole wall roughness using a U-Net model and image processing algorithms.This study established an unplated copper PCB CT image dataset and trained an improved U-Net model.Validation of the test set demonstrated that the improved model effectively segmented microholes in the PCB CT images.Subsequently,the roughness of the holes’walls was assessed using a customized image-processing algorithm.Comparative analysis between CT detection based on various edge detection algorithms and slice detection revealed that CT detection employing the Canny algorithm closely approximates slice detection,yielding range and average errors of 2.92 and 1.64μm,respectively.Hence,the detection method proposed in this paper offers a novel approach for nondestructive testing of hole wall roughness in the PCB industry. 展开更多
关键词 PCB CT image segmentation improved u-net model Hole wall roughness Micro-CT non-destructive testing
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Extraction of fractures in shale CT images using improved U-Net 被引量:2
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作者 Xiang Wu Fei Wang +3 位作者 Xiaoqiu Zhang Bohua Han Qianru Liu Yonghao Zhang 《Energy Geoscience》 EI 2024年第2期240-248,共9页
Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response analysis.However,fractures in CT images are similar in grayscal... Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response analysis.However,fractures in CT images are similar in grayscale to the rock matrix,and traditional algorithms have difficulty to achieve accurate segmentation results.In this study,a dataset containing multiscale fracture information was constructed,and a U-Net semantic segmentation model with a scSE attention mechanism was used to classify shale CT images at the pixel level and compare the results with traditional methods.The results showed that the CLAHE algorithm effectively removed noise and enhanced the fracture information in the dark parts,which is beneficial for further fracture extraction.The Canny edge detection algorithm had significant false positives and failed to recognize the internal information of the fractures.The Otsu algorithm only extracted fractures with a significant difference from the background and was not sensitive enough for fine fractures.The MEF algorithm enhanced the edge information of the fractures and was also sensitive to fine fractures,but it overestimated the aperture of the fractures.The U-Net was able to identify almost all fractures with good continuity,with an MIou and Recall of 0.80 and 0.82,respectively.As the image resolution increases,more fine fracture information can be extracted. 展开更多
关键词 CT slices Fracture segmentation SHALE u-net Deep learning
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Detection of Precipitation Cloud over the Tibet Based on the Improved U-Net 被引量:2
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作者 Runzhe Tao Yonghong Zhang +2 位作者 Lihua Wang Pengyan Cai Haowen Tan 《Computers, Materials & Continua》 SCIE EI 2020年第12期2455-2474,共20页
Aiming at the problem of radar base and ground observation stations on the Tibet is sparsely distributed and cannot achieve large-scale precipitation monitoring.U-Net,an advanced machine learning(ML)method,is used to ... Aiming at the problem of radar base and ground observation stations on the Tibet is sparsely distributed and cannot achieve large-scale precipitation monitoring.U-Net,an advanced machine learning(ML)method,is used to develop a robust and rapid algorithm for precipitating cloud detection based on the new-generation geostationary satellite of FengYun-4A(FY-4A).First,in this algorithm,the real-time multi-band infrared brightness temperature from FY-4A combined with the data of Digital Elevation Model(DEM)has been used as predictor variables for our model.Second,the efficiency of the feature was improved by changing the traditional convolution layer serial connection method of U-Net to residual mapping.Then,in order to solve the problem of the network that would produce semantic differences when directly concentrated with low-level and high-level features,we use dense skip pathways to reuse feature maps of different layers as inputs for concatenate neural networks feature layers from different depths.Finally,according to the characteristics of precipitation clouds,the pooling layer of U-Net was replaced by a convolution operation to realize the detection of small precipitation clouds.It was experimentally concluded that the Pixel Accuracy(PA)and Mean Intersection over Union(MIoU)of the improved U-Net on the test set could reach 0.916 and 0.928,the detection of precipitation clouds over Tibet were well actualized. 展开更多
关键词 u-net fy-4a precipitation cloud dense skip connections residual network
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Enhancement of Biomass Material Characterization Images Using an Improved U-Net 被引量:1
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作者 Zuozheng Lian Hong Zhao +2 位作者 Qianjun Zhang Haizhen Wang E.Erdun 《Computers, Materials & Continua》 SCIE EI 2022年第7期1515-1528,共14页
For scanning electronmicroscopes with high resolution and a strong electric field,biomass materials under observation are prone to radiation damage from the electron beam.This results in blurred or non-viable images,w... For scanning electronmicroscopes with high resolution and a strong electric field,biomass materials under observation are prone to radiation damage from the electron beam.This results in blurred or non-viable images,which affect further observation of material microscopic morphology and characterization.Restoring blurred images to their original sharpness is still a challenging problem in image processing.Traditionalmethods can’t effectively separate image context dependency and texture information,affect the effect of image enhancement and deblurring,and are prone to gradient disappearance during model training,resulting in great difficulty in model training.In this paper,we propose the use of an improvedU-Net(U-shapedConvolutional Neural Network)to achieve image enhancement for biomass material characterization and restore blurred images to their original sharpness.The main work is as follows:use of depthwise separable convolution instead of standard convolution in U-Net to reduce model computation effort and parameters;embedding wavelet transform into the U-Net structure to separate image context and texture information,thereby improving image reconstruction quality;using dense multi-receptive field channel modules to extract image detail information,thereby better transmitting the image features and network gradients,and reduce the difficulty of training.The experiments show that the improved U-Net model proposed in this paper is suitable and effective for enhanced deblurring of biomass material characterization images.The PSNR(Peak Signal-to-noise Ratio)and SSIM(Structural Similarity)are enhanced as well. 展开更多
关键词 u-net wavelet transform image enhancement biomass material characterization
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Seismic multiple attenuation based on improved U-Net
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作者 Quan Zhang Xiao-yu Lv +3 位作者 Qin Lei Bo Peng Yan Li Yao-wen Zhang 《Applied Geophysics》 SCIE CSCD 2024年第4期680-696,879,共18页
Eff ective attenuation of seismic multiples is a crucial step in the seismic data processing workfl ow.Despite the existence of various methods for multiple attenuation,challenges persist,such as incomplete attenuatio... Eff ective attenuation of seismic multiples is a crucial step in the seismic data processing workfl ow.Despite the existence of various methods for multiple attenuation,challenges persist,such as incomplete attenuation and high computational requirements,particularly in complex geological conditions.Conventional multiple attenuation methods rely on prior geological information and involve extensive computations.Using deep neural networks for multiple attenuation can effectively reduce manual labor costs while improving the efficiency of multiple suppression.This study proposes an improved U-net-based method for multiple attenuation.The conventional U-net serves as the primary network,incorporating an attentional local contrast module to effectively process detailed information in seismic data.Emphasis is placed on distinguishing between seismic multiples and primaries.The improved network is trained using seismic data containing both multiples and primaries as input and seismic data containing only primaries as output.The eff ectiveness and stability of the proposed method in multiple attenuation are validated using two horizontal layered velocity models and the Sigsbee2B velocity model.Transfer learning is employed to endow the trained model with the capability to suppress multiples across seismic exploration areas,eff ectively improving multiple attenuation efficiency. 展开更多
关键词 Multiple suppression u-net Attentional local contrast
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A Lightweight Improved U-Net with Shallow Features Combination and Its Application to Defect Detection
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作者 WU Hong SUN Xiankur XIONG Yujie 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2020年第5期461-468,共8页
In order to solve the problems of shallow features loss and high computation cost of U-Net,we propose a lightweight with shallow features combination(IU-Net).IU-Net adds several convolution layers and short links to t... In order to solve the problems of shallow features loss and high computation cost of U-Net,we propose a lightweight with shallow features combination(IU-Net).IU-Net adds several convolution layers and short links to the skip path to extract more shallow features.At the same time,the original convolution is replaced by the depth-wise separable convolution to reduce the calculation cost and the number of parameters.IU-Net is applied to detecting small metal industrial products defects.It is evaluated on our own SUES-Washer dataset to verify the effectiveness.Experimental results demonstrate that our proposed method outperforms the original U-Net,and it has 1.73%,2.08%and 11.2%improvement in the intersection over union,accuracy,and detection time,respectively,which satisfies the requirements of industrial detection. 展开更多
关键词 u-net depth-wise separable convolution shallow features combination defect detection
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A New Method for Image Tamper Detection Based on an Improved U-Net
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作者 Jie Zhang Jianxun Zhang +2 位作者 Bowen Li Jie Cao Yifan Guo 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2883-2895,共13页
With the improvement of image editing technology,the threshold of image tampering technology decreases,which leads to a decrease in the authenticity of image content.This has also driven research on image forgery dete... With the improvement of image editing technology,the threshold of image tampering technology decreases,which leads to a decrease in the authenticity of image content.This has also driven research on image forgery detection techniques.In this paper,a U-Net with multiple sensory field feature extraction(MSCU-Net)for image forgery detection is proposed.The proposed MSCU-Net is an end-to-end image essential attribute segmentation network that can perform image forgery detection without any pre-processing or post-processing.MSCU-Net replaces the single-scale convolution module in the original network with an improved multiple perceptual field convolution module so that the decoder can synthesize the features of different perceptual fields use residual propagation and residual feedback to recall the input feature information and consolidate the input feature information to make the difference in image attributes between the untampered and tampered regions more obvious,and introduce the channel coordinate confusion attention mechanism(CCCA)in skip-connection to further improve the segmentation accuracy of the network.In this paper,extensive experiments are conducted on various mainstream datasets,and the results verify the effectiveness of the proposed method,which outperforms the state-of-the-art image forgery detection methods. 展开更多
关键词 Forgery detection multiple receptive fields cyclic residuals u-net channel coordinate confusion attention
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ICA-Unet:An improved U-net network for brown adipose tissue segmentation
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作者 Haolin Wang Zhonghao Wang +4 位作者 Jingle Wang Kang Li Guohua Geng Fei Kang Xin Cao 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第3期70-80,共11页
Brown adipose tissue(BAT)is a kind of adipose tissue engaging in thermoregulatory thermogenesis,metaboloregulatory thermogenesis,and secretory.Current studies have revealed that BAT activity is negatively correlated w... Brown adipose tissue(BAT)is a kind of adipose tissue engaging in thermoregulatory thermogenesis,metaboloregulatory thermogenesis,and secretory.Current studies have revealed that BAT activity is negatively correlated with adult body weight and is considered a target tissue for the treatment of obesity and other metabolic-related diseases.Additionally,the activity of BAT presents certain differences between different ages and genders.Clinically,BAT segmentation based on PET/CT data is a reliable method for brown fat research.However,most of the current BAT segmentation methods rely on the experience of doctors.In this paper,an improved U-net network,ICA-Unet,is proposed to achieve automatic and precise segmentation of BAT.First,the traditional 2D convolution layer in the encoder is replaced with a depth-wise overparameterized convolutional(Do-Conv)layer.Second,the channel attention block is introduced between the double-layer convolution.Finally,the image information entropy(IIE)block is added in the skip connections to strengthen the edge features.Furthermore,the performance of this method is evaluated on the dataset of PET/CT images from 368 patients.The results demonstrate a strong agreement between the automatic segmentation of BAT and manual annotation by experts.The average DICE coeffcient(DSC)is 0.9057,and the average Hausdorff distance is 7.2810.Experimental results suggest that the method proposed in this paper can achieve effcient and accurate automatic BAT segmentation and satisfy the clinical requirements of BAT. 展开更多
关键词 PET/CT segmentation of brown adipose tissue u-net medical image processing deep learning
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Tea Leaf Disease Diagnosis Based on Improved Lightweight U-Net3+
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作者 HU Yumeng GUAN Feifan +5 位作者 XIE Dongchen MA Ping YU Youben ZHOU Jie NIE Yanming HUANG Lüwen 《智慧农业(中英文)》 2026年第1期15-27,共13页
[Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis... [Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis of the severity of tea spots was proposed in this research,designated as MDC-U-Net3+,to enhance segmentation accuracy on the base framework of U-Net3+.[Methods]Multi-scale feature fusion module(MSFFM)was incorporated into the backbone network of U-Net3+to obtain feature information across multiple receptive fields of diseased spots,thereby reducing the loss of features within the encoder.Dual multi-scale attention(DMSA)was incorporated into the skip connection process to mitigate the segmentation boundary ambiguity issue.This integration facilitates the comprehensive fusion of fine-grained and coarse-grained semantic information at full scale.Furthermore,the segmented mask image was subjected to conditional random fields(CRF)to enhance the optimization of the segmentation results[Results and Discussions]The improved model MDC-U-Net3+achieved a mean pixel accuracy(mPA)of 94.92%,accompanied by a mean Intersection over Union(mIoU)ratio of 90.9%.When compared to the mPA and mIoU of U-Net3+,MDC-U-Net3+model showed improvements of 1.85 and 2.12 percentage points,respectively.These results illustrated a more effective segmentation performance than that achieved by other classical semantic segmentation models.[Conclusions]The methodology presented herein could provide data support for automated disease detection and precise medication,consequently reducing the losses associated with tea diseases. 展开更多
关键词 disease diagnosis semantic segmentation u-net3+ multi-scale feature fusion attention mechanism conditional random fields
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A Novel Improved Puma Optimizer to Boost Photovoltaic Array Production in Partially Shaded Environments
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作者 Nagwan Abdel Samee Ahmed Fathy +2 位作者 Mohamed A.Mahdy Maali Alabdulhafith Essam H.Houssein 《Computer Modeling in Engineering & Sciences》 2026年第2期737-771,共35页
This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raph... This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raphson search rule(NRSR)to boost the exploration process,especially in search spaces with more local regions,and boost the exploitation with adaptive parameters alternating with random parameters in the original Puma.The effectiveness of the introduced IPuma is confirmed through comprehensive evaluations on the CEC’20 benchmark problems.It shows superior performance compared to both established and modern metaheuristic algorithms in terms of effectively navigating the search space and achieving convergence towards near-optimal regions.The findings indicated that the IPuma algorithm demonstrates considerable statistical promise and surpasses the performance of competing algorithms.In addition,the proposed IPuma is utilized to reconfigure a 9×9 PV array that operates under different shade patterns,such as lower triangular(LT),long wide(LW),and short wide(SW).In addition to other programmed approaches,such as the Whale optimization algorithm(WOA),grey wolf optimizer(GWO),Harris Hawks optimization(HHO),particle swarm optimization(PSO),gravitational search algorithm(GSA),biogeography-based optimization(BBO),sine cosine algorithm(SCA),equilibrium optimizer(EO),and original Puma,the indicated method is contrasted to the traditional configurations of TCT and Sudoku.In addition,the metrics of mismatch power loss,maximum efficiency improvement,efficiency improvement ratio,and peak-to-mean ratio are calculated to assess the effectiveness of the indicated approach.The proposed IPuma improved the generated power by 36.72%,28.03%,and 40.97%for SW,LW,and LT,respectively,outperforming the TCT configuration.In addition,it achieved the best maximum efficiency improvement among the algorithms considered,with 26.86%,21.89%,and 29.07%for the examined patterns.The results highlight the superiority and competence of the proposed approach in both convergence rates and stability,as well as applicability to dynamically reconfigure the PV system and enhance its harvested energy. 展开更多
关键词 Photovoltaic partial shade RECONFIGURATION improved puma METAHEURISTIC
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PEMFC Performance Degradation Prediction Based on CNN-BiLSTM with Data Augmentation by an Improved GAN
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作者 Xiaolu Wang Haoyu Sun +1 位作者 Aiguo Wang Xin Xia 《Energy Engineering》 2026年第2期417-435,共19页
To address the issues of insufficient and imbalanced data samples in proton exchange membrane fuel cell(PEMFC)performance degradation prediction,this study proposes a data augmentation-based model to predict PEMFC per... To address the issues of insufficient and imbalanced data samples in proton exchange membrane fuel cell(PEMFC)performance degradation prediction,this study proposes a data augmentation-based model to predict PEMFC performance degradation.Firstly,an improved generative adversarial network(IGAN)with adaptive gradient penalty coefficient is proposed to address the problems of excessively fast gradient descent and insufficient diversity of generated samples.Then,the IGANis used to generate datawith a distribution analogous to real data,therebymitigating the insufficiency and imbalance of original PEMFC samples and providing the predictionmodel with training data rich in feature information.Finally,a convolutional neural network-bidirectional long short-termmemory(CNN-BiLSTM)model is adopted to predict PEMFC performance degradation.Experimental results show that the data generated by the proposed IGAN exhibits higher quality than that generated by the original GAN,and can fully characterize and enrich the original data’s features.Using the augmented data,the prediction accuracy of the CNN-BiLSTM model is significantly improved,rendering it applicable to tasks of predicting PEMFC performance degradation. 展开更多
关键词 PEMFC performance degradation prediction data augmentation improved generative adversarial network
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An improved conditional denoising diffusion GAN for Mach number field reconstruction in a multi-tunnel combined inlet based on sparse parameter information
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作者 Ke MIN Fan LEI +2 位作者 Jiale ZHANG Chengxiang ZHU Yancheng YOU 《Chinese Journal of Aeronautics》 2026年第1期169-190,共22页
The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To... The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To develop an efficient flow field reconstruction model for this,we present an Improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN),which integrates Conditional Denoising Diffusion Probabilistic Models(CDDPMs)with Style GAN,and introduce a reconstruction discrimination mechanism and dynamic loss weight learning strategy.We establish the Mach number flow field dataset by numerical simulation at various backpressures for the mode transition process from turbine mode to ejector ramjet mode at Mach number 2.5.The proposed ICDDGAN model,given only sparse parameter information,can rapidly generate high-quality Mach number flow fields without a large number of samples for training.The results show that ICDDGAN is superior to CDDGAN in terms of training convergence and stability.Moreover,the interpolation and extrapolation test results during backpressure conditions show that ICDDGAN can accurately and quickly reconstruct Mach number fields at various tunnel slice shapes,with a Structural Similarity Index Measure(SSIM)of over 0.96 and a Mean-Square Error(MSE)of 0.035%to actual flow fields,reducing time costs by 7-8 orders of magnitude compared to Computational Fluid Dynamics(CFD)calculations.This can provide an efficient means for rapid computation of complex flow fields. 展开更多
关键词 Flow field reconstruction improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN) Mode transition Sparse parameter information Three-dimensional inward-tunning combined inlet
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Enhancing 3D U-Net with Residual and Squeeze-and-Excitation Attention Mechanisms for Improved Brain Tumor Segmentation in Multimodal MRI
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作者 Yao-Tien Chen Nisar Ahmad Khursheed Aurangzeb 《Computer Modeling in Engineering & Sciences》 2025年第7期1197-1224,共28页
Accurate and efficient brain tumor segmentation is essential for early diagnosis,treatment planning,and clinical decision-making.However,the complex structure of brain anatomy and the heterogeneous nature of tumors pr... Accurate and efficient brain tumor segmentation is essential for early diagnosis,treatment planning,and clinical decision-making.However,the complex structure of brain anatomy and the heterogeneous nature of tumors present significant challenges for precise anomaly detection.While U-Net-based architectures have demonstrated strong performance in medical image segmentation,there remains room for improvement in feature extraction and localization accuracy.In this study,we propose a novel hybrid model designed to enhance 3D brain tumor segmentation.The architecture incorporates a 3D ResNet encoder known for mitigating the vanishing gradient problem and a 3D U-Net decoder.Additionally,to enhance the model’s generalization ability,Squeeze and Excitation attention mechanism is integrated.We introduce Gabor filter banks into the encoder to further strengthen the model’s ability to extract robust and transformation-invariant features from the complex and irregular shapes typical in medical imaging.This approach,which is not well explored in current U-Net-based segmentation frameworks,provides a unique advantage by enhancing texture-aware feature representation.Specifically,Gabor filters help extract distinctive low-level texture features,reducing the effects of texture interference and facilitating faster convergence during the early stages of training.Our model achieved Dice scores of 0.881,0.846,and 0.819 for Whole Tumor(WT),Tumor Core(TC),and Enhancing Tumor(ET),respectively,on the BraTS 2020 dataset.Cross-validation on the BraTS 2021 dataset further confirmed the model’s robustness,yielding Dice score values of 0.887 for WT,0.856 for TC,and 0.824 for ET.The proposed model outperforms several state-of-the-art existing models,particularly in accurately identifying small and complex tumor regions.Extensive evaluations suggest integrating advanced preprocessing with an attention-augmented hybrid architecture offers significant potential for reliable and clinically valuable brain tumor segmentation. 展开更多
关键词 3D MRI artificial intelligence deep learning AI in healthcare attention mechanism u-net medical image analysis brain tumor segmentation BraTS 2021 BraTS 2020
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基于改进U-Net的铜合金晶界识别方法
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作者 靖青秀 刘卫辉 +4 位作者 常琪琪 谢伟滨 张志聪 吴瑞洋 黄晓东 《有色金属(中英文)》 北大核心 2026年第2期198-206,共9页
晶粒度评级精度高度依赖于准确的晶粒尺寸与形状表征,而晶界分割是界定晶粒范围的关键预处理步骤。针对铜合金显微图像中晶界对比度低、边缘模糊导致的检测困难,以及现有高精度分割算法参数量大、计算复杂度高、难以满足工业实时检测需... 晶粒度评级精度高度依赖于准确的晶粒尺寸与形状表征,而晶界分割是界定晶粒范围的关键预处理步骤。针对铜合金显微图像中晶界对比度低、边缘模糊导致的检测困难,以及现有高精度分割算法参数量大、计算复杂度高、难以满足工业实时检测需求等问题,本文提出一种基于MobileNetV2的轻量化U-Net改进方法。通过将MobileNetV2作为主干网络解决特征丢失问题,并引入集成深度可分离卷积的ASPP模块,有效增强了多尺度语义特征提取能力。实验结果表明,改进后的模型在保持轻量化的同时,在晶界分割任务中取得了mIOU 87.66%、精确率93.50%、平均像素准确率92.79%的优异性能,显著优于传统U-Net模型,为工业现场实时晶界识别提供了可靠解决方案。 展开更多
关键词 铜合金 晶粒度 深度学习 u-net 轻量化
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基于多尺度特征提取的U-Net网络微地震定位方法
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作者 黄建平 王秋阳 +6 位作者 李媛媛 黎国龙 苏来源 路依霖 李三福 段文胜 雷刚林 《中国石油大学学报(自然科学版)》 北大核心 2026年第1期1-11,共11页
微地震定位是微地震监测的核心任务,面对当前海量的地震数据,传统的定位方法已无法满足实时定位的需求。为此,利用深度学习技术,提出一种基于U-Net网络为主要架构的微地震震源定位方法,通过融合双交叉注意力模块和空间空洞金字塔池化模... 微地震定位是微地震监测的核心任务,面对当前海量的地震数据,传统的定位方法已无法满足实时定位的需求。为此,利用深度学习技术,提出一种基于U-Net网络为主要架构的微地震震源定位方法,通过融合双交叉注意力模块和空间空洞金字塔池化模块,增强网络对微震数据中波形特征的提取能力,提升震源位置预测精度。最后,利用简单层状和复杂速度模型生成合成数据进行实验测试,并与U-Net和Att-Unet网络对震源位置预测误差精度进行对比分析。结果表明,所构建的网络模型在震源预测精度以及网络性能上均优于其他网络模型,并且对低信噪比的微地震数据也有较好的预测效果。 展开更多
关键词 微震定位 水力压裂 多尺度特征提取 u-net网络 注意力机制
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基于改进U-Net网络和知识蒸馏的三维断层识别方法
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作者 王莉利 梁云虎 高新成 《石油物探》 北大核心 2026年第1期21-30,共10页
深度学习方法在三维地震资料断层识别中得到了广泛应用,但方法的应用面临数据集质量欠佳、资源消耗过高以及训练周期长等问题。为此,提出了一种融合改进U-Net网络和知识蒸馏的三维断层识别方法。该方法先将改进的U-Net网络模型作为教师... 深度学习方法在三维地震资料断层识别中得到了广泛应用,但方法的应用面临数据集质量欠佳、资源消耗过高以及训练周期长等问题。为此,提出了一种融合改进U-Net网络和知识蒸馏的三维断层识别方法。该方法先将改进的U-Net网络模型作为教师模型,将空洞空间金字塔池化(ASPP)结构与U-Net网络模型相融合,构建轻量级学生模型,然后引入知识蒸馏技术对学生模型进行优化,并调整网络训练超参数和知识蒸馏损失参数,使学生模型获取更丰富的断层信息,提升学生模型的网络性能。该方法通过将复杂的教师模型的知识迁移到轻量级学生模型,显著降低了模型的计算复杂度,同时保持了较高的识别精度。测试结果表明,在合成测试集和实际地震数据的断层识别中,经过知识蒸馏训练的学生模型在识别精度和连续性上均优于未经过蒸馏的学生模型和单独训练的教师模型,充分验证了方法的可行性和有效性。 展开更多
关键词 断层识别 知识蒸馏 u-net 教师模型 学生模型
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融合对抗自编码器和U-net的非侵入式负荷分解方法
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作者 王凌云 朱倍萱 +1 位作者 张涛 罗明天 《电力系统及其自动化学报》 北大核心 2026年第2期59-68,共10页
为了提高非侵入式负荷分解模型的分解效果和泛化性能,并针对现有生成式模型在非侵入式负荷分解任务中存在的一些局限性,提出一种引入变分推理思想和联合对抗机制的对抗自编码器非侵入式负荷分解方法。为保证负荷分解的实时性,采用序列... 为了提高非侵入式负荷分解模型的分解效果和泛化性能,并针对现有生成式模型在非侵入式负荷分解任务中存在的一些局限性,提出一种引入变分推理思想和联合对抗机制的对抗自编码器非侵入式负荷分解方法。为保证负荷分解的实时性,采用序列到序列映射模型。基于U-net框架构建对抗自编码器模型,在编码器与解码器之间添加跳跃连接,使模型可以同时捕获电器特征的局部细节和全局信息,实现多特征融合,避免特征丢失,同时引入实例-批归一化网络,提高模型的分解性能以及泛化性能。最后将所提模型与几种代表性模型在UK-DALE数据集上进行对比实验。结果表明:所提模型具有优秀的分解性能和泛化能力,并且更加轻量化。 展开更多
关键词 非侵入式负荷分解 对抗自编码器 深度学习 序列到序列 u-net 实例-批归一化
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Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China 被引量:1
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作者 Jiarui Cai Bo Sun +5 位作者 Huijun Wang Yi Zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong 《Atmospheric and Oceanic Science Letters》 2025年第1期18-23,共6页
Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in th... Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many areas.In this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,China.The two models combine the improved dung beetle optimizer(DBO)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-Long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with DBO show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original DBO,the R and RPD of models with the improved DBO increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction results.In addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance. 展开更多
关键词 Groundwater depth Multi-head attention improved dung beetle optimizer CNN-LSTM CNN-GRU Ningxia
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Improved methods,properties,applications and prospects of microbial induced carbonate precipitation(MICP)treated soil:A review 被引量:2
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作者 Xuanshuo Zhang Hongyu Wang +3 位作者 Ya Wang Jinghui Wang Jing Cao Gang Zhang 《Biogeotechnics》 2025年第1期34-54,共21页
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi... Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications. 展开更多
关键词 Soil improvement Bio-cement MICP improved methods Field application cases
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融合多源特征与注意力机制的改进U-Net鱼鳞坑遥感提取方法
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作者 魏敬志 黄骁力 +4 位作者 江岭 梁明 张大鹏 王莎莎 宋音 《农业工程学报》 北大核心 2026年第2期214-224,共11页
鱼鳞坑是黄土高原典型的小型水土保持措施,由于其尺度小、分布不均,传统卫星遥感方法难以实现高精度识别。为此,该研究提出一种融合多源特征与注意力机制的深度学习鱼鳞坑遥感提取方法,构建了“特征重要性分析+注意力增强U-Net结构设计... 鱼鳞坑是黄土高原典型的小型水土保持措施,由于其尺度小、分布不均,传统卫星遥感方法难以实现高精度识别。为此,该研究提出一种融合多源特征与注意力机制的深度学习鱼鳞坑遥感提取方法,构建了“特征重要性分析+注意力增强U-Net结构设计”的技术框架。基于无人机获取的高分辨率多光谱影像与数字高程模型(digital elevation model,DEM),该研究综合运用Spearman相关系数与SHAP(Shapley additive explanations)可解释性分析方法,对光谱与地形特征进行重要性评估与冗余剔除,最终优选出4类关键特征,并据此设计了9种特征组合方案。在此基础上,采用UNet、DeepLabV3+、SegNet与FCN四种语义分割模型开展对比试验,结果表明以RGB+Slope的特征组合方案在UNet模型中识别效果最优。在模型结构方面,该研究以U-Net为基础,融合金字塔压缩注意力模块(pyramid squeeze attention module,PSAM)与多级特征注意力上采样模块(multi-scale feature attention upsampling module,MFAU),增强模型对鱼鳞坑边缘与空间结构的感知能力,并设计消融试验验证改进效果。试验结果表明,在最优特征组合的数据输入下,改进模型在测试区交并比提升2.47个百分点,F1分数提升1.34个百分点,召回率提升2.72个百分点,精确率提升1.02个百分点,表现出良好的提取精度与区域泛化能力。研究表明,特征重要性分析与注意力增强结构设计的融合策略可有效提升模型对小尺度地貌目标的识别性能,为鱼鳞坑等微地形构筑物的高精度遥感提取提供技术支撑,也为多源信息融合与深度学习模型构建提供了理论参考。 展开更多
关键词 无人机 遥感 语义分割 鱼鳞坑提取 u-net改进 注意力机制
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