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LP-YOLO:Enhanced Smoke and Fire Detection via Self-Attention and Feature Pyramid Integration
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作者 Qing Long Bing Yi +2 位作者 Haiqiao Liu Zhiling Peng Xiang Liu 《Computers, Materials & Continua》 2026年第3期1490-1509,共20页
Accurate detection of smoke and fire sources is critical for early fire warning and environmental monitoring.However,conventional detection approaches are highly susceptible to noise,illumination variations,and comple... Accurate detection of smoke and fire sources is critical for early fire warning and environmental monitoring.However,conventional detection approaches are highly susceptible to noise,illumination variations,and complex environmental conditions,which often reduce detection accuracy and real-time performance.To address these limitations,we propose Lightweight and Precise YOLO(LP-YOLO),a high-precision detection framework that integrates a self-attention mechanism with a feature pyramid,built upon YOLOv8.First,to overcome the restricted receptive field and parameter redundancy of conventional Convolutional Neural Networks(CNNs),we design an enhanced backbone based on Wavelet Convolutions(WTConv),which expands the receptive field through multifrequency convolutional processing.Second,a Bidirectional Feature Pyramid Network(BiFPN)is employed to achieve bidirectional feature fusion,enhancing the representation of smoke features across scales.Third,to mitigate the challenge of ambiguous object boundaries,we introduce the Frequency-aware Feature Fusion(FreqFusion)module,in which the Adaptive Low-Pass Filter(ALPF)reduces intra-class inconsistencies,the offset generator refines boundary localization,and the Adaptive High-Pass Filter(AHPF)recovers high-frequency details lost during down-sampling.Experimental evaluations demonstrate that LP-YOLO significantly outperforms the baseline YOLOv8,achieving an improvement of 9.3%in mAP@50 and 9.2%in F1-score.Moreover,the model is 56.6%and 32.4%smaller than YOLOv7-tiny and EfficientDet,respectively,while maintaining real-time inference speed at 238 frames per second(FPS).Validation on multiple benchmark datasets,including D-Fire,FIRESENSE,and BoWFire,further confirms its robustness and generalization ability,with detection accuracy consistently exceeding 82%.These results highlight the potential of LP-YOLO as a practical solution with high accuracy,robustness,and real-time performance for smoke and fire source detection. 展开更多
关键词 Deep learning smoke detection feature pyramid boundary refinement
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EHDC-YOLO: Enhancing Object Detection for UAV Imagery via Multi-Scale Edge and Detail Capture
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作者 Zhiyong Deng Yanchen Ye Jiangling Guo 《Computers, Materials & Continua》 2026年第1期1665-1682,共18页
With the rapid expansion of drone applications,accurate detection of objects in aerial imagery has become crucial for intelligent transportation,urban management,and emergency rescue missions.However,existing methods ... With the rapid expansion of drone applications,accurate detection of objects in aerial imagery has become crucial for intelligent transportation,urban management,and emergency rescue missions.However,existing methods face numerous challenges in practical deployment,including scale variation handling,feature degradation,and complex backgrounds.To address these issues,we propose Edge-enhanced and Detail-Capturing You Only Look Once(EHDC-YOLO),a novel framework for object detection in Unmanned Aerial Vehicle(UAV)imagery.Based on the You Only Look Once version 11 nano(YOLOv11n)baseline,EHDC-YOLO systematically introduces several architectural enhancements:(1)a Multi-Scale Edge Enhancement(MSEE)module that leverages multi-scale pooling and edge information to enhance boundary feature extraction;(2)an Enhanced Feature Pyramid Network(EFPN)that integrates P2-level features with Cross Stage Partial(CSP)structures and OmniKernel convolutions for better fine-grained representation;and(3)Dynamic Head(DyHead)with multi-dimensional attention mechanisms for enhanced cross-scale modeling and perspective adaptability.Comprehensive experiments on the Vision meets Drones for Detection(VisDrone-DET)2019 dataset demonstrate that EHDC-YOLO achieves significant improvements,increasing mean Average Precision(mAP)@0.5 from 33.2%to 46.1%(an absolute improvement of 12.9 percentage points)and mAP@0.5:0.95 from 19.5%to 28.0%(an absolute improvement of 8.5 percentage points)compared with the YOLOv11n baseline,while maintaining a reasonable parameter count(2.81 M vs the baseline’s 2.58 M).Further ablation studies confirm the effectiveness of each proposed component,while visualization results highlight EHDC-YOLO’s superior performance in detecting objects and handling occlusions in complex drone scenarios. 展开更多
关键词 UAV imagery object detection multi-scale feature fusion edge enhancement detail preservation YOLO feature pyramid network attention mechanism
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Enhancing Underwater Monocular Depth Estimation with Lpg-Lap Unet for Target Tracking Mission
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作者 YAO Peng WANG Yalu 《Journal of Ocean University of China》 2026年第1期161-170,共10页
Accurately estimating depth from underwater monocular images is essential for the target tracking task of unmanned underwater vehicles.This work proposes a method based on the Lpg-Lap Unet architecture.First,the Unet ... Accurately estimating depth from underwater monocular images is essential for the target tracking task of unmanned underwater vehicles.This work proposes a method based on the Lpg-Lap Unet architecture.First,the Unet architecture integrates Laplacian pyramid depth residuals and Sobel operators to improve the boundary details in depth images,which may suffer from the feature loss caused by upsampling and the blurriness of underwater images.Multiscale local planar guidance layers then fully exploit the intermediate depth features,and a comprehensive loss function ensures robustness and accuracy.Experimental results on benchmarks demonstrate the effectiveness of Lpg-Lap Unet and its superior performance over state-of-the-art models.An underwater target tracking system is then designed to further validate its real-time capabilities in the AirSim simulation platform. 展开更多
关键词 underwater monocular depth estimation Laplacian pyramid multiscale local planar guidance underwater target tracking
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基于改进YOLOv11的CNN-Transformer混合水域垃圾检测算法
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作者 赵建永 李瑞东 +1 位作者 姚浩 魏秀蓉 《无线互联科技》 2026年第4期21-25,50,共6页
河流水面漂浮物检测受限于复杂环境条件(如光照变化、波纹干扰)和检测目标尺度较小的特点,传统方法难以实现高精度检测。文章提出一种面向复杂水域场景的单阶段检测模型YOLOv11n-SPT,在YOLOv11n基础上引入新型Spatial Pyramid Transform... 河流水面漂浮物检测受限于复杂环境条件(如光照变化、波纹干扰)和检测目标尺度较小的特点,传统方法难以实现高精度检测。文章提出一种面向复杂水域场景的单阶段检测模型YOLOv11n-SPT,在YOLOv11n基础上引入新型Spatial Pyramid Transformer(SPT)模块与通道注意力机制。SPT模块采用多分支空间金字塔结构,实现高分辨率细节保留与超大感受野全局建模的协同。在FloW-Img数据集上,YOLOv11n-SPT的mAP@0.5达到81.2%,较基线YOLOv11n提升2.9个百分点;消融实验表明,单独引入SPT模块使mAP@0.5提升2.0%,召回率提升2.1%,进一步叠加通道注意力后精确率提升至85.4%。YOLOv11n-SPT在微小目标与强干扰场景下表现出更强的鲁棒性与定位精度,为无人清漂船、无人机巡河等实际水域环境治理任务提供了高效可靠的感知方案。 展开更多
关键词 水面漂浮物检测 Spatial Pyramid Transformer YOLOv11
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A Novel Self-Supervised Learning Network for Binocular Disparity Estimation 被引量:1
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作者 Jiawei Tian Yu Zhou +5 位作者 Xiaobing Chen Salman A.AlQahtani Hongrong Chen Bo Yang Siyu Lu Wenfeng Zheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期209-229,共21页
Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical robots.This st... Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical robots.This study proposes a novel end-to-end disparity estimation model to address these challenges.Our approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting interferences.This study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and efficiency.The model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video data.Experimental results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing parameters.Moreover,the model exhibited faster convergence during training,contributing to overall performance enhancement.This study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments. 展开更多
关键词 Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation
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DCA-YOLO:Detection Algorithm for YOLOv8 Pulmonary Nodules Based on Attention Mechanism Optimization 被引量:2
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作者 SONG Yongsheng LIU Guohua 《Journal of Donghua University(English Edition)》 2025年第1期78-87,共10页
Pulmonary nodules represent an early manifestation of lung cancer.However,pulmonary nodules only constitute a small portion of the overall image,posing challenges for physicians in image interpretation and potentially... Pulmonary nodules represent an early manifestation of lung cancer.However,pulmonary nodules only constitute a small portion of the overall image,posing challenges for physicians in image interpretation and potentially leading to false positives or missed detections.To solve these problems,the YOLOv8 network is enhanced by adding deformable convolution and atrous spatial pyramid pooling(ASPP),along with the integration of a coordinate attention(CA)mechanism.This allows the network to focus on small targets while expanding the receptive field without losing resolution.At the same time,context information on the target is gathered and feature expression is enhanced by attention modules in different directions.It effectively improves the positioning accuracy and achieves good results on the LUNA16 dataset.Compared with other detection algorithms,it improves the accuracy of pulmonary nodule detection to a certain extent. 展开更多
关键词 pulmonary nodule YOLOv8 network object detection deformable convolution atrous spatial pyramid pooling(ASPP) coordinate attention(CA)mechanism
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Feature pyramid attention network for audio-visual scene classification 被引量:1
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作者 Liguang Zhou Yuhongze Zhou +3 位作者 Xiaonan Qi Junjie Hu Tin Lun Lam Yangsheng Xu 《CAAI Transactions on Intelligence Technology》 2025年第2期359-374,共16页
Audio-visual scene classification(AVSC)poses a formidable challenge owing to the intricate spatial-temporal relationships exhibited by audio-visual signals,coupled with the complex spatial patterns of objects and text... Audio-visual scene classification(AVSC)poses a formidable challenge owing to the intricate spatial-temporal relationships exhibited by audio-visual signals,coupled with the complex spatial patterns of objects and textures found in visual images.The focus of recent studies has predominantly revolved around extracting features from diverse neural network structures,inadvertently neglecting the acquisition of semantically meaningful regions and crucial components within audio-visual data.The authors present a feature pyramid attention network(FPANet)for audio-visual scene understanding,which extracts semantically significant characteristics from audio-visual data.The authors’approach builds multi-scale hierarchical features of sound spectrograms and visual images using a feature pyramid representation and localises the semantically relevant regions with a feature pyramid attention module(FPAM).A dimension alignment(DA)strategy is employed to align feature maps from multiple layers,a pyramid spatial attention(PSA)to spatially locate essential regions,and a pyramid channel attention(PCA)to pinpoint significant temporal frames.Experiments on visual scene classification(VSC),audio scene classification(ASC),and AVSC tasks demonstrate that FPANet achieves performance on par with state-of-the-art(SOTA)approaches,with a 95.9 F1-score on the ADVANCE dataset and a relative improvement of 28.8%.Visualisation results show that FPANet can prioritise semantically meaningful areas in audio-visual signals. 展开更多
关键词 dimension alignment feature pyramid attention network pyramid channel attention pyramid spatial attention semantic relevant regions
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Jamming recognition method based on wavelet packet decomposition and improved deep learning 被引量:1
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作者 Qi Wu Gang Li +4 位作者 Xiang Wang Hao Luo Lianghong Li Qianbin Chen Xiaorong Jing 《Digital Communications and Networks》 2025年第5期1469-1478,共10页
To overcome the challenges of poor real-time performance,limited scalability,and low intelligence in conventional jamming pattern recognition methods,this paper proposes a method based on Wavelet Packet Decomposition(... To overcome the challenges of poor real-time performance,limited scalability,and low intelligence in conventional jamming pattern recognition methods,this paper proposes a method based on Wavelet Packet Decomposition(WPD)and enhanced deep learning techniques.In the proposed method,an agent at the receiver processes the received signal using WPD to generate an initial Spectrogram Waterfall(SW),which is subsequently segmented using a sliding window to serve as the input for the jamming recognition network.The network employs a bilateral filter to preprocess the input SW,thereby enhancing the edge features of the jamming signals.To extract abstract features,depthwise separable convolution is utilized instead of traditional convolution,thereby reducing the network’s parameter count and enhancing real-time performance.A pyramid pooling layer is integrated before the fully connected layer to enable the network to process input SW of varying sizes,thus enhancing scalability.During network training,adaptive moment estimation is employed as the optimizer,allowing the network to dynamically adjust the learning rate and accelerate convergence.A comprehensive comparison between the proposed jamming recognition network and six other models is conducted,along with Ablation Experiments(AE)based on numerical simulations.Simulation results demonstrate that the proposed method based on WPD and enhanced deep learning achieves high-precision recognition of various jamming patterns while maintaining a favorable balance among prediction accuracy,network complexity,and prediction time. 展开更多
关键词 Wavelet packet decomposition Improved deep learning Spectrogram waterfall Pyramid pooling Jamming recognition
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Strain rate-dependent tension-compression asymmetry in cast Mg-Gd-Y alloy:Insights into slip and twinning mechanisms 被引量:1
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作者 Jingli Li Huicong Chen +3 位作者 Di Wu Rongshi Chen Jun Song Xin Yi 《Journal of Materials Science & Technology》 2025年第16期134-146,共13页
Tension-compression asymmetry is a critical concern for magnesium(Mg)alloys,particularly in automo-tive crash structures.This study systematically examines the tension-compression asymmetry of a cast Mg-Gd-Y alloy at ... Tension-compression asymmetry is a critical concern for magnesium(Mg)alloys,particularly in automo-tive crash structures.This study systematically examines the tension-compression asymmetry of a cast Mg-Gd-Y alloy at various strain rates.Experimental results indicate symmetric yielding stress under both tension and compression at all strain rates,along with a reduction in the tension-compression asym-metry of ultimate stress and plastic strain as the strain rate increases.This trend arises from an unusual strain rate-dependent tension-compression asymmetry,characterized by strain rate toughening in tension and negligible strain rate effect in compression.The differing behavior is linked to the distinct twinning mechanisms under tension and compression.The suppression of twinning under tension contributes to the positive strain rate dependence of pyramidal slip,whereas the activation of abundant twins during compression means that pyramidal slip is unnecessary to accommodate c-axis strain,leading to the ab-sence of a strain rate effect in compression.Abundant twins nucleate consistently from yielding to 2%strain,but only after basal and prismaticslip have mediated microplasticity,suggesting that these slip systems reduce the nucleation stress for twinning during compression,resulting in a lower activation stress for twinning compared to tension.This study provides new insights into micromechanisms of the tension-compression asymmetry in cast Mg-Gd-Y alloys and offers practical guidance for the application of these materials in critical components that must endure both tension and compression under varying strain rates. 展开更多
关键词 Magnesium rare-earth(Mg-RE)alloys Stress state Strain rate Pyramidal slip Twin nucleation Rare-earth effect
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Hybrid receptive field network for small object detection on drone view 被引量:1
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作者 Zhaodong CHEN Hongbing JI +2 位作者 Yongquan ZHANG Wenke LIU Zhigang ZHU 《Chinese Journal of Aeronautics》 2025年第2期322-338,共17页
Drone-based small object detection is of great significance in practical applications such as military actions, disaster rescue, transportation, etc. However, the severe scale differences in objects captured by drones... Drone-based small object detection is of great significance in practical applications such as military actions, disaster rescue, transportation, etc. However, the severe scale differences in objects captured by drones and lack of detail information for small-scale objects make drone-based small object detection a formidable challenge. To address these issues, we first develop a mathematical model to explore how changing receptive fields impacts the polynomial fitting results. Subsequently, based on the obtained conclusions, we propose a simple but effective Hybrid Receptive Field Network (HRFNet), whose modules include Hybrid Feature Augmentation (HFA), Hybrid Feature Pyramid (HFP) and Dual Scale Head (DSH). Specifically, HFA employs parallel dilated convolution kernels of different sizes to extend shallow features with different receptive fields, committed to improving the multi-scale adaptability of the network;HFP enhances the perception of small objects by capturing contextual information across layers, while DSH reconstructs the original prediction head utilizing a set of high-resolution features and ultrahigh-resolution features. In addition, in order to train HRFNet, the corresponding dual-scale loss function is designed. Finally, comprehensive evaluation results on public benchmarks such as VisDrone-DET and TinyPerson demonstrate the robustness of the proposed method. Most impressively, the proposed HRFNet achieves a mAP of 51.0 on VisDrone-DET with 29.3 M parameters, which outperforms the extant state-of-the-art detectors. HRFNet also performs excellently in complex scenarios captured by drones, achieving the best performance on the CS-Drone dataset we built. 展开更多
关键词 Drone remote sensing Object detection on drone view Small object detector Hybrid receptive field Feature pyramid network Feature augmentation Multi-scale object detection
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Optimized Convolutional Neural Networks with Multi-Scale Pyramid Feature Integration for Efficient Traffic Light Detection in Intelligent Transportation Systems 被引量:1
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作者 Yahia Said Yahya Alassaf +2 位作者 Refka Ghodhbani Taoufik Saidani Olfa Ben Rhaiem 《Computers, Materials & Continua》 2025年第2期3005-3018,共14页
Transportation systems are experiencing a significant transformation due to the integration of advanced technologies, including artificial intelligence and machine learning. In the context of intelligent transportatio... Transportation systems are experiencing a significant transformation due to the integration of advanced technologies, including artificial intelligence and machine learning. In the context of intelligent transportation systems (ITS) and Advanced Driver Assistance Systems (ADAS), the development of efficient and reliable traffic light detection mechanisms is crucial for enhancing road safety and traffic management. This paper presents an optimized convolutional neural network (CNN) framework designed to detect traffic lights in real-time within complex urban environments. Leveraging multi-scale pyramid feature maps, the proposed model addresses key challenges such as the detection of small, occluded, and low-resolution traffic lights amidst complex backgrounds. The integration of dilated convolutions, Region of Interest (ROI) alignment, and Soft Non-Maximum Suppression (Soft-NMS) further improves detection accuracy and reduces false positives. By optimizing computational efficiency and parameter complexity, the framework is designed to operate seamlessly on embedded systems, ensuring robust performance in real-world applications. Extensive experiments using real-world datasets demonstrate that our model significantly outperforms existing methods, providing a scalable solution for ITS and ADAS applications. This research contributes to the advancement of Artificial Intelligence-driven (AI-driven) pattern recognition in transportation systems and offers a mathematical approach to improving efficiency and safety in logistics and transportation networks. 展开更多
关键词 Intelligent transportation systems(ITS) traffic light detection multi-scale pyramid feature maps advanced driver assistance systems(ADAS) real-time detection AI in transportation
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New discovery of Mayan civilization
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作者 刘晨青 《疯狂英语(新悦读)》 2025年第9期47-48,78,共3页
Archaeologists(考古学家)have unearthed the remains of a Mayan city nearly 3,000 years old in northern Guatemala,with pyramids(金字塔)and monuments that showcase its significance as an important ceremonial site.The May... Archaeologists(考古学家)have unearthed the remains of a Mayan city nearly 3,000 years old in northern Guatemala,with pyramids(金字塔)and monuments that showcase its significance as an important ceremonial site.The Mayan civilization arose around 2000 BC,reaching its height between 400 AD and 900 AD in what is present-day southern Mexico and Guatemala,as well as parts of Belize,El Salvador and Honduras. 展开更多
关键词 ARCHAEOLOGISTS REMAINS PYRAMIDS Mayan civilization city MONUMENTS ceremonial site northern Guatemala
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Double Self-Attention Based Fully Connected Feature Pyramid Network for Field Crop Pest Detection
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作者 Zijun Gao Zheyi Li +2 位作者 Chunqi Zhang Ying Wang Jingwen Su 《Computers, Materials & Continua》 2025年第6期4353-4371,共19页
Pest detection techniques are helpful in reducing the frequency and scale of pest outbreaks;however,their application in the actual agricultural production process is still challenging owing to the problems of intersp... Pest detection techniques are helpful in reducing the frequency and scale of pest outbreaks;however,their application in the actual agricultural production process is still challenging owing to the problems of interspecies similarity,multi-scale,and background complexity of pests.To address these problems,this study proposes an FD-YOLO pest target detection model.The FD-YOLO model uses a Fully Connected Feature Pyramid Network(FC-FPN)instead of a PANet in the neck,which can adaptively fuse multi-scale information so that the model can retain small-scale target features in the deep layer,enhance large-scale target features in the shallow layer,and enhance the multiplexing of effective features.A dual self-attention module(DSA)is then embedded in the C3 module of the neck,which captures the dependencies between the information in both spatial and channel dimensions,effectively enhancing global features.We selected 16 types of pests that widely damage field crops in the IP102 pest dataset,which were used as our dataset after data supplementation and enhancement.The experimental results showed that FD-YOLO’s mAP@0.5 improved by 6.8%compared to YOLOv5,reaching 82.6%and 19.1%–5%better than other state-of-the-art models.This method provides an effective new approach for detecting similar or multiscale pests in field crops. 展开更多
关键词 Pest detection YOLOv5 feature pyramid network transformer attention module
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Tension-compression asymmetry of pyramidal dislocations in magnesium
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作者 Zikun Li Chuanlong Xu +3 位作者 Xiaobao Tian Wentao Jiang Qingyuan Wang Haidong Fan 《Journal of Magnesium and Alloys》 2025年第7期3198-3208,共11页
Pyramidal dislocations are important for ductility enhancement of magnesium alloys.In this work,molecular dynamics simulations were employed to study the gliding behavior of pyramidal(c+a)dislocations under c-axis com... Pyramidal dislocations are important for ductility enhancement of magnesium alloys.In this work,molecular dynamics simulations were employed to study the gliding behavior of pyramidal(c+a)dislocations under c-axis compressive loading and tensile loading.The Peierls stress of Py-Ⅰ dislocation shows strong tension-compression asymmetry.However,no tension-compression asymmetry is seen on the Py-Ⅱ dislocation and basal dislocation.The tension-compression asymmetry origins from the asymmetry of partial dislocations of Py-Ⅰ dislocation,which leads to the dislocation core contracted under c-axis compressive loading and expanded under tensile loading.By analyzing the forces acting on the partial dislocations,we defined a neutral direction,which deviates from the full dislocation Burgers vector by 70.3°.The neutral direction is dependent on the ratio of lattice stresses of partial dislocations.If the shear stress is applied along the neutral direction,tension-compression asymmetry is eliminated and the dislocation core is un-contracted/un-expanded.The neutral direction of symmetrical dislocations(Py-Ⅱ dislocation and basal dislocation)is just the full dislocation Burgers vector.The tension-compression asymmetry and dislocation core contraction/expansion have an important influence on the dislocation behaviors,such as cross-slip,decomposition,basaltransition and mobility,which can be used to explain the mechanical behaviors of Mg single-crystals compressed along c-axis. 展开更多
关键词 Tension-compression asymmetry Pyramidal dislocation MAGNESIUM Molecular dynamics
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Understanding pyramidal slip-induced deformation bands and dynamic recrystallization in AZWX3100 magnesium alloy
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作者 Risheng Pei Fatim-Zahra Mouhib +3 位作者 Mattis Seehaus Simon Arnoldi Pei-Ling Sun Talal Al-Samman 《Journal of Magnesium and Alloys》 2025年第3期1088-1098,共11页
Dynamic recrystallization(DRX)in inhomogeneous deformation zones,such as grain boundaries,shear bands,and deformation bands,is critical for texture modification in magnesium alloys during deformation at elevated temper... Dynamic recrystallization(DRX)in inhomogeneous deformation zones,such as grain boundaries,shear bands,and deformation bands,is critical for texture modification in magnesium alloys during deformation at elevated temperatures.This study investigates the DRX mechanisms in AZWX3100 magnesium alloy under plane strain compression at 200℃.Microstructural analysis revealed necklace-type DRX accompanied by evidence of local grain boundary bulging.Additionally,ribbons of recrystallized grains were observed withinfine deformation bands,aligned with theoretical pyramidal I and II slip traces derived from the matrix.The distribution of local misorientation within the deformed microstructure demonstrated a clear association between deformation bands and localized strain.Dislocation analysis of lamellar specimens extracted from two pyramidal slip bands revealed<c+a>dislocations,indicating a connection between<c+a>slip activation and the formation of deformation bands.Crystal plasticity simulations suggest that the orientation of deformation bands is responsible for the unique recrystallization texture of the DRX grains within these bands.The texture characteristics imply a progressive,glide-induced DRX mechanism.A fundamental understanding of the role of deformation bands in texture modification can facilitate future alloy and process design. 展开更多
关键词 MAGNESIUM Channel die Dynamic recrystallization Texture modification Pyramidal slip
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Statistical investigation on the tension-compression asymmetry of slip behavior and plastic heterogeneity in an aged Mg-10Y sheet
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作者 Ran Ni Huashen Liu +3 位作者 Shen Hua Hao Zhou Ying Zeng Dongdi Yin 《Journal of Magnesium and Alloys》 2025年第8期3880-3895,共16页
The grain-scale tension-compression(T-C)asymmetric slip behavior and geometrically necessary dislocation(GND)density in an aged and twin-free Mg-10Y sheet were statistically studied using slip trace analysis and elect... The grain-scale tension-compression(T-C)asymmetric slip behavior and geometrically necessary dislocation(GND)density in an aged and twin-free Mg-10Y sheet were statistically studied using slip trace analysis and electron backscatter diffraction(EBSD)analysis.A significantly asymmetric slip activity,i.e.,higher tensile slip activity and proportion of non-basal slip,was manifested.Prismatic〈a〉(37.1%)and basal〈a〉(27.6%)slips dominated the tensile deformation,followed by pyramidalⅡ〈c+a〉slip(20.0%).While during compression,basal〈a〉slip(61.9%)was the most active slip mode,and only 6.9% pyramidalⅡ〈c+a〉slip was observed.The critical resolved shear stress(CRSS)ratio was estimated based on~800 sets of the identified slip traces,which suggested that the CRSS_(pyrⅡ)/CRSS_(bas)for compression was~3 times than that of tension.The pyramidalⅡ〈c+a〉slip was more active when the slip plane was under tension than under compression,which was consistent with the calculated asymmetric CRSS_(pyrⅡ)/CRSS_(bas).The activity of multiple slip,cross slip and slip transfer,as well as the GND density were also T-C asymmetric.This work thoughtfully demonstrated the T-C asymmetric slip behavior and plastic heterogeneity in Mg alloys which was believed to be responsible for the macroscopic T-C asymmetry when twinning was absent.The present statistical results are valuable for validating and/or facilitating crystal plasticity simulations. 展开更多
关键词 Mg alloy Tension-compression asymmetry Slip behavior Pyramidal slip GND density
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Ultralong discharge time enabled using etched germanium anodes in germanium-air batteries
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作者 Ya Han Yingjian Yu 《Chinese Chemical Letters》 2025年第7期603-607,共5页
Germanium(Ge)-air battery,a new type of semiconductor-air battery,has garnered increasing attention owing to its environmental friendliness,safety,and excellent dynamic performance.However,the flat Ge anode is prone t... Germanium(Ge)-air battery,a new type of semiconductor-air battery,has garnered increasing attention owing to its environmental friendliness,safety,and excellent dynamic performance.However,the flat Ge anode is prone to passivation,owing to GeO_(2) accumulation on its surface,resulting in premature discharge termination.In this study,various nano-Ge pyramid structures(GePS)were prepared using chemical etching(CE)and metal-assisted chemical etching(MACE)methods to enhance the specific surface area of the Ge anode,thereby facilitating the dissolution of the passivation layer.This study revealed that the MACE method significantly accelerated the etching rate of the Ge surface,producing exceptional GePS.Furthermore,Ge-air batteries employing Ge anodes prepared using MACE demonstrated an exceptional discharge life of up to 9240 h(385 days).The peak power density reached 3.03mW/cm^(2),representing improvements of more than 2 times and 1.8 times,respectively,compared with batteries using flat Ge anodes.This study presents a straightforward approach to enhance Ge anode performance,thereby expanding the potential applications of Ge-air batteries. 展开更多
关键词 Ge-air battery Ultralong discharge time PASSIVATION Metal-assisted chemical etching Pyramid structure
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Super-Resolution Generative Adversarial Network with Pyramid Attention Module for Face Generation
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作者 Parvathaneni Naga Srinivasu G.JayaLakshmi +4 位作者 Sujatha Canavoy Narahari Victor Hugo C.de Albuquerque Muhammad Attique Khan Hee-Chan Cho Byoungchol Chang 《Computers, Materials & Continua》 2025年第10期2117-2139,共23页
The generation of high-quality,realistic face generation has emerged as a key field of research in computer vision.This paper proposes a robust approach that combines a Super-Resolution Generative Adversarial Network(... The generation of high-quality,realistic face generation has emerged as a key field of research in computer vision.This paper proposes a robust approach that combines a Super-Resolution Generative Adversarial Network(SRGAN)with a Pyramid Attention Module(PAM)to enhance the quality of deep face generation.The SRGAN framework is designed to improve the resolution of generated images,addressing common challenges such as blurriness and a lack of intricate details.The Pyramid Attention Module further complements the process by focusing on multi-scale feature extraction,enabling the network to capture finer details and complex facial features more effectively.The proposed method was trained and evaluated over 100 epochs on the CelebA dataset,demonstrating consistent improvements in image quality and a marked decrease in generator and discriminator losses,reflecting the model’s capacity to learn and synthesize high-quality images effectively,given adequate computational resources.Experimental outcome demonstrates that the SRGAN model with PAM module has outperformed,yielding an aggregate discriminator loss of 0.055 for real,0.043 for fake,and a generator loss of 10.58 after training for 100 epochs.The model has yielded an structural similarity index measure of 0.923,that has outperformed the other models that are considered in the current study for analysis. 展开更多
关键词 Artificial intelligence generative adversarial network pyramid attention module face generation deep learning
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On the origin of non-basal texture in extruded Mg-RE alloys and its implication for texture engineering
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作者 X.Z.Jin G.J.Yang +5 位作者 Xinyu Xu D.B.Shan B.Guo B.B.He C.Fan W.C.Xu 《Journal of Magnesium and Alloys》 2025年第8期3642-3658,共17页
The work aims to investigate the formation and transformation mechanism of non-basal texture in the extruded Mg alloys.With this purpose a pure Mg as reference and eight Mg-Gd binary alloys with the Gd concentration r... The work aims to investigate the formation and transformation mechanism of non-basal texture in the extruded Mg alloys.With this purpose a pure Mg as reference and eight Mg-Gd binary alloys with the Gd concentration ranging from 0.5 wt.%to 18 wt.%were prepared for extrusion.This study shows that the basal fiber texture in pure Mg transited into RE(rare earth)texture in diluted Mg-Gd alloys and into the abnormal C-texture in high-concentration Mg-Gd alloys.In pure Mg,discontinuous dynamic recrystallization plays a predominant role during the extrusion process,resulting in the formation of a typical basal fiber texture.Alloying with high concentration of Gd impedes the dynamic recrystallization process,facilitating the heterogeneous nucleation of shear bands as well as the dynamic recrystallization within shear bands.Dynamic recrystallized grains within shear bands nucleate with a similar orientation to the host deformed parent grains and gradually tilt their c-axis to the extrusion direction during growth by absorbing dislocations,leading to the formation of either the REtexture orientation or the C-texture orientation,depending on the stored energy within shear bands.The analysis aided by IGMA and TEM characterization reveals that the shear bands originate from the extensive but heterogeneous activation of pyramidal I slip.Tensile tests illustrate a close correlation between the fracture elongation and texture types.A comprehensive understanding of the formation and transformation mechanism of different texture components in Mg alloys holds significant importance for the design of high-performance Mg alloys by texture engineering. 展开更多
关键词 Mg alloys Dynamic recrystallization Shear bands Pyramidal I slip Texture engineering
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Weld Defect Monitoring Based on Two-Stage Convolutional Neural Network
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作者 XIAO Wenbo XIONG Jiakai +2 位作者 YU Lesheng HE Yinshui MA Guohong 《Journal of Shanghai Jiaotong university(Science)》 2025年第2期291-299,共9页
Zn vapour is easily generated on the surface by fusion welding galvanized steel sheet,resulting in the formation of defects.Rapidly developing computer vision sensing technology collects weld images in the welding pro... Zn vapour is easily generated on the surface by fusion welding galvanized steel sheet,resulting in the formation of defects.Rapidly developing computer vision sensing technology collects weld images in the welding process,then obtains laser fringe information through digital image processing,identifies welding defects,and finally realizes online control of weld defects.The performance of a convolutional neural network is related to its structure and the quality of the input image.The acquired original images are labeled with LabelMe,and repeated attempts are made to determine the appropriate filtering and edge detection image preprocessing methods.Two-stage convolutional neural networks with different structures are built on the Tensorflow deep learning framework,different thresholds of intersection over union are set,and deep learning methods are used to evaluate the collected original images and the preprocessed images separately.Compared with the test results,the comprehensive performance of the improved feature pyramid networks algorithm based on the basic network VGG16 is lower than that of the basic network Resnet101.Edge detection of the image will significantly improve the accuracy of the model.Adding blur will reduce the accuracy of the model slightly;however,the overall performance of the improved algorithm is still relatively good,which proves the stability of the algorithm.The self-developed software inspection system can be used for image preprocessing and defect recognition,which can be used to record the number and location of typical defects in continuous welds. 展开更多
关键词 defects monitoring image preprocessing Resnet101 feature pyramid network
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