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The potential of deformable titanium reinforced magnesium-matrix composites:A review of preparation,characterization,and performance evaluation
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作者 Yitao Wang Jianbo Li +6 位作者 Huan Luo Weizhang Wang Daiyi Deng Jianwei Chen Xianhua Chen Kaihong Zheng Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第8期3490-3523,共34页
Magnesium matrix composites(MMCs)combine exceptional low density,high specific strength,and stiffness,positioning them as critical materials for aerospace,automotive,and electronics industries.This review highlights r... Magnesium matrix composites(MMCs)combine exceptional low density,high specific strength,and stiffness,positioning them as critical materials for aerospace,automotive,and electronics industries.This review highlights recent progress in the fabrication of Ti-Mg composites and analyzes the mechanisms behind their enhanced mechanical properties.A key focus is the interfacial deformation incompatibility between Ti and Mg phases,which generates strain gradients and promotes the accumulation of geometrically necessary dislocations(GNDs)at the interface.This process not only improves strain hardening and ductility but also reveals the need for advanced micromechanical models to capture the plastic behavior of both phases.The review critically examines the impact of different Mg matrix types(AZ,AM,VW series)and the role of interfacial product morphology and size on bonding and overall performance.Furthermore,Ti reinforcement endows the composites with superior wear resistance and thermal conductivity,indicating broad application potential. 展开更多
关键词 Magnesium matrix composites deformable Ti reinforcement Mechanical properties
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DA-ViT:Deformable Attention Vision Transformer for Alzheimer’s Disease Classification from MRI Scans
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作者 Abdullah G.M.Almansour Faisal Alshomrani +4 位作者 Abdulaziz T.M.Almutairi Easa Alalwany Mohammed S.Alshuhri Hussein Alshaari Abdullah Alfahaid 《Computer Modeling in Engineering & Sciences》 2025年第8期2395-2418,共24页
The early and precise identification of Alzheimer’s Disease(AD)continues to pose considerable clinical difficulty due to subtle structural alterations and overlapping symptoms across the disease phases.This study pre... The early and precise identification of Alzheimer’s Disease(AD)continues to pose considerable clinical difficulty due to subtle structural alterations and overlapping symptoms across the disease phases.This study presents a novel Deformable Attention Vision Transformer(DA-ViT)architecture that integrates deformable Multi-Head Self-Attention(MHSA)with a Multi-Layer Perceptron(MLP)block for efficient classification of Alzheimer’s disease(AD)using Magnetic resonance imaging(MRI)scans.In contrast to traditional vision transformers,our deformable MHSA module preferentially concentrates on spatially pertinent patches through learned offset predictions,markedly diminishing processing demands while improving localized feature representation.DA-ViT contains only 0.93 million parameters,making it exceptionally suitable for implementation in resource-limited settings.We evaluate the model using a class-imbalanced Alzheimer’s MRI dataset comprising 6400 images across four categories,achieving a test accuracy of 80.31%,a macro F1-score of 0.80,and an area under the receiver operating characteristic curve(AUC)of 1.00 for the Mild Demented category.Thorough ablation studies validate the ideal configuration of transformer depth,headcount,and embedding dimensions.Moreover,comparison research indicates that DA-ViT surpasses state-of-theart pre-trained Convolutional Neural Network(CNN)models in terms of accuracy and parameter efficiency. 展开更多
关键词 Alzheimer disease classification vision transformer deformable attention MRI analysis bayesian optimization
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CW-HRNet:Constrained Deformable Sampling and Wavelet-Guided Enhancement for Lightweight Crack Segmentation
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作者 Dewang Ma 《Journal of Electronic Research and Application》 2025年第5期269-280,共12页
This paper presents CW-HRNet,a high-resolution,lightweight crack segmentation network designed to address challenges in complex scenes with slender,deformable,and blurred crack structures.The model incorporates two ke... This paper presents CW-HRNet,a high-resolution,lightweight crack segmentation network designed to address challenges in complex scenes with slender,deformable,and blurred crack structures.The model incorporates two key modules:Constrained Deformable Convolution(CDC),which stabilizes geometric alignment by applying a tanh limiter and learnable scaling factor to the predicted offsets,and the Wavelet Frequency Enhancement Module(WFEM),which decomposes features using Haar wavelets to preserve low-frequency structures while enhancing high-frequency boundaries and textures.Evaluations on the CrackSeg9k benchmark demonstrate CW-HRNet’s superior performance,achieving 82.39%mIoU with only 7.49M parameters and 10.34 GFLOPs,outperforming HrSegNet-B48 by 1.83% in segmentation accuracy with minimal complexity overhead.The model also shows strong cross-dataset generalization,achieving 60.01%mIoU and 66.22%F1 on Asphalt3k without fine-tuning.These results highlight CW-HRNet’s favorable accuracyefficiency trade-off for real-world crack segmentation tasks. 展开更多
关键词 Crack segmentation Lightweight semantic segmentation deformable convolution Wavelet transform Road infrastructure
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4D printing of direct-driven deformable wheel with multiple programmable configurations
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作者 Huichun Tian Guanghao Chu +3 位作者 Bin Zhou Dekai Zhou Jing Qiao Longqiu Li 《International Journal of Extreme Manufacturing》 2025年第3期369-381,共13页
Conventional deformable wheel systems in robots and other mechatronic systems face significant challenges in achieving miniaturization,intelligence,and integration.To address these issues,we propose a novel integrated... Conventional deformable wheel systems in robots and other mechatronic systems face significant challenges in achieving miniaturization,intelligence,and integration.To address these issues,we propose a novel integrated structural design method and four-dimensional printing strategy for deformable wheels capable of shaping among multiple programmable direct-driven deformation configurations.The load-bearing capacity of the printed wheel is strengthened by employing deformed components in various locations and actuated states.Additionally,a novel analytical design method is presented to determine the structure,actuation,and deformation parameters of each component under complex coupled deformation.Our findings reveal that the designed wheel can transform into three different configurations,exhibiting desired deformations of 12.5%in the radial direction and 19.6%in the axial direction.It also demonstrates robust deformation behavior and structural stability under multi-directional loads.By integrating a terrain sensing system,the designed wheel exhibits highly adaptive deformation capabilities on various terrains,showing great potential for exploring complex environments. 展开更多
关键词 4D printing deformable wheel continuous fiber multifunctional structure system integration
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基于改进Deformable DETR模型的多源局部放电识别方法及其应用 被引量:5
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作者 雷志鹏 彭川 +4 位作者 许子涵 姜宛廷 李传扬 吝伶艳 彭邦发 《中国电机工程学报》 EI CSCD 北大核心 2024年第15期6248-6260,I0035,共14页
基于图像的局部放电识别方法大部分仅对单源局部放电谱图有效,无法识别多源局部放电谱图。为实现对多源局部放电谱图的识别,该文提出一种基于Transformer架构的局部放电Deformable DETR目标检测模型,收集典型单源局部放电和多源局部放... 基于图像的局部放电识别方法大部分仅对单源局部放电谱图有效,无法识别多源局部放电谱图。为实现对多源局部放电谱图的识别,该文提出一种基于Transformer架构的局部放电Deformable DETR目标检测模型,收集典型单源局部放电和多源局部放电数据,生成局部放电相位角解析和极坐标相位分布解析谱图数据集。在Deformable DETR模型中引入去噪训练任务和贝叶斯优化算法,优化了局部放电目标检测模型;编写局部放电谱图采集和识别程序,并使用优化后的局部放电Deformable DETR模型对单源和多源局部放电谱图进行识别。结果表明:局部放电Deformable DETR模型不仅可有效识别出单源和多源局部放电的类型,而且大幅提升了局部放电类型识别的收敛速度和精度等性能。在对真实绝缘缺陷电动机的局部放电谱图识别中,局部放电Deformable DETR模型的识别准确率达到91%,证明该模型在实际应用中的有效性。 展开更多
关键词 局部放电 模式识别 deformableDETR 目标检测 多源局部放电
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基于改进Deformable-DETR的水下图像目标检测方法 被引量:4
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作者 崔颖 韩佳成 +1 位作者 高山 陈立伟 《应用科技》 CAS 2024年第1期30-36,91,共8页
针对由于水下复杂环境造成的目标检测效果较差、检测精度较低的问题,基于Deformable-DETR算法提出一种改进的水下目标检测算法Deformable-DETR-DA。使用空间注意力模块结合标准Transformer块设计了一个用于增加模型深度的深度特征金字塔... 针对由于水下复杂环境造成的目标检测效果较差、检测精度较低的问题,基于Deformable-DETR算法提出一种改进的水下目标检测算法Deformable-DETR-DA。使用空间注意力模块结合标准Transformer块设计了一个用于增加模型深度的深度特征金字塔(deep feature pyramid networks,DFPN)模块,将其嵌入到模型中提高模型对深层纹理信息的提取能力。使用注意力引导的方式对原模型中编码器部分进行改进,加强了对特征信息的聚合能力,提高了模型在复杂环境下的检测能力。针对URPC数据集,模型各交并比尺度的平均准确度(average precision,AP)为39.5%,相比原模型提升1%,与一些DETR(detection transformer)类的模型相比,不同目标尺度的平均准确度均有1%~4%左右的提高,表明改进的模型能够很好解决复杂环境的水下目标检测的问题。本文提出的模型可作为其他水下目标检测模型设计的参考。 展开更多
关键词 水下光学图像 deformable-DETR 目标检测 TRANSFORMER 注意力机制 深度学习 图像处理 残差网络
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基于改进Deformable DETR的无人机视频流车辆目标检测算法 被引量:6
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作者 江志鹏 王自全 +4 位作者 张永生 于英 程彬彬 赵龙海 张梦唯 《计算机工程与科学》 CSCD 北大核心 2024年第1期91-101,共11页
针对无人机视频流检测中小目标数量多、因图像传输质量较低而导致的上下文语义信息不充分、传统算法融合特征推理速度慢、数据集类别样本不均衡导致的训练效果差等问题,提出一种基于改进Deformable DETR的无人机视频流车辆目标检测算法... 针对无人机视频流检测中小目标数量多、因图像传输质量较低而导致的上下文语义信息不充分、传统算法融合特征推理速度慢、数据集类别样本不均衡导致的训练效果差等问题,提出一种基于改进Deformable DETR的无人机视频流车辆目标检测算法。在模型结构方面,该算法设计了跨尺度特征融合模块以增大感受野,提升小目标检测能力,并采用针对object_query的挤压-激励模块提升关键目标的响应值,减少重要目标的漏检与错检率;在数据处理方面,使用了在线困难样本挖掘技术,改善数据集中类别样本分布不均的问题。在UAVDT数据集上进行了实验,实验结果表明,改进后的算法相较于基线算法在平均检测精度上提升了1.5%,在小目标检测精度上提升了0.8%,并在保持参数量较少增长的情况下,维持了原有的检测速度。 展开更多
关键词 deformable DETR 目标检测 跨尺度特征融合模块 object query挤压-激励 在线难样本挖掘
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Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction 被引量:2
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作者 Fengshun Wang Lingbin Xie +7 位作者 Ning Sun Ting Zhi Mengyang Zhang Yang Liu Zhongzhong Luo Lanhua Yi Qiang Zhao Longlu Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期287-311,共25页
Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent year... Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst. 展开更多
关键词 deformable catalytic material Micro-nanostructures evolution Mechanical flexibility Hydrogen evolution reaction
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Fuzzy Proportional Integral Derivative control of a voice coil actuator system for adaptive deformable mirrors 被引量:2
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作者 Ziqiang Cui Heng Zuo +4 位作者 Weikang Qiao Hao Li Fujia Du Yifan Wang Jinrui Guo 《Astronomical Techniques and Instruments》 CSCD 2024年第3期179-186,共8页
Research on adaptive deformable mirror technology for voice coil actuators(VCAs)is an important trend in the development of large ground-based telescopes.A voice coil adaptive deformable mirror contains a large number... Research on adaptive deformable mirror technology for voice coil actuators(VCAs)is an important trend in the development of large ground-based telescopes.A voice coil adaptive deformable mirror contains a large number of actuators,and there are problems with structural coupling and large temperature increases in their internal coils.Additionally,parameters of the traditional proportional integral derivative(PID)control cannot be adjusted in real-time to adapt to system changes.These problems can be addressed by introducing fuzzy control methods.A table lookup method is adopted to replace real-time calculations of the regular fuzzy controller during the control process,and a prototype platform has been established to verify the effectiveness and robustness of this process.Experimental tests compare the control performance of traditional and fuzzy proportional integral derivative(Fuzzy-PID)controllers,showing that,in system step response tests,the fuzzy control system reduces rise time by 20.25%,decreases overshoot by 78.24%,and shortens settling time by 67.59%.In disturbance rejection experiments,fuzzy control achieves a 46.09%reduction in the maximum deviation,indicating stronger robustness.The Fuzzy-PID controller,based on table lookup,outperforms the standard controller significantly,showing excellent potential for enhancing the dynamic performance and disturbance rejection capability of the voice coil motor actuator system. 展开更多
关键词 Adaptive optics deformable mirror Voice coil actuator Fuzzy control
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基于Deformable DETR的自然场景任意形状文本检测 被引量:1
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作者 张子旭 游钰玮 +1 位作者 仝明磊 薛亮 《无线电工程》 2024年第2期312-318,共7页
自然场景下的文本区域形状复杂多变,直接使用轮廓坐标描述文本区域会使得建模不充分,导致文本检测准确性低。针对自然场景下文本区域不规则的问题,提出了一种基于Deformable DETR的任意形状文本检测模型,不同于传统的直接预测轮廓点的方... 自然场景下的文本区域形状复杂多变,直接使用轮廓坐标描述文本区域会使得建模不充分,导致文本检测准确性低。针对自然场景下文本区域不规则的问题,提出了一种基于Deformable DETR的任意形状文本检测模型,不同于传统的直接预测轮廓点的方法,使用B-样条对文字区域进行建模使得文本轮廓平滑精确的同时减少了需要预测的参数。提出的文本检测模型无需手工设计锚点、区域建议等组件,极大地简化了模型设计并提高了通用性。提出的模型在无需额外数据集的情况下在任意形状文本数据集CTW1500和Total-Text上的平均精度(F值)分别达到了85.4%和85.0%,证明了模型的有效性。 展开更多
关键词 计算机视觉 自然场景文本检测 deformable DETR B-样条
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基于Deformable DETR的红外图像目标检测方法研究 被引量:3
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作者 张晓宇 杜祥润 +2 位作者 张佳梁 檀盼龙 杨诗博 《空天防御》 2024年第1期16-23,共8页
基于Transformer架构的DETR系列网络在计算机视觉目标检测领域不断刷新目标检测的精度与速度。然而,基于红外图像的非合作目标检测的应用环境复杂,而且红外图像质量较差。针对该问题,提出了一种新的以Deformable DETR算法为基线的具有... 基于Transformer架构的DETR系列网络在计算机视觉目标检测领域不断刷新目标检测的精度与速度。然而,基于红外图像的非合作目标检测的应用环境复杂,而且红外图像质量较差。针对该问题,提出了一种新的以Deformable DETR算法为基线的具有高检测精度的目标检测算法:首先设计了对红外图像进行图像增强处理的图像增强模块CLAHE-GB,并将其与Deformable DETR进行有机结合;然后在大型通用数据集上进行预训练;最后引入数据增强和迁移学习方法在自制的空中飞行物小型红外图像数据集中对检测头网络参数进行再训练,并对结果进行分析。结果表明:所提出的算法对红外图像数据具有较好的图像增强效果和检测精度。 展开更多
关键词 红外图像 图像增强 deformable DETR算法 目标检测
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基于DEFORM的风电轴承保持架窗口冲裁过程仿真研究
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作者 刘晟杰 万光虎 +5 位作者 聂延艳 王黎明 王燕霜 杜雨 李剑峰 李方义 《机械设计与研究》 北大核心 2025年第3期272-278,共7页
主轴轴承保持架是风力发电机的关键组件,冲裁是保持架制造的基本工艺。多种冲裁参数对保持架的断面质量起到决定性作用,但目前缺乏对其冲裁过程的有限元仿真,无法系统优化冲裁参数。鉴于此,以DEFORM有限元软件为基础,揭示了冲裁中工艺... 主轴轴承保持架是风力发电机的关键组件,冲裁是保持架制造的基本工艺。多种冲裁参数对保持架的断面质量起到决定性作用,但目前缺乏对其冲裁过程的有限元仿真,无法系统优化冲裁参数。鉴于此,以DEFORM有限元软件为基础,揭示了冲裁中工艺参数和断面质量的复杂关联,基于响应曲面法实现了冲裁参数的优化。首先,利用DEFORM软件,系统分析冲裁速度、冲裁间隙和凸模刃口圆角半径对保持架窗口断面质量的综合影响,三者的最佳组合能有效提升产品的表面质量。然后,通过响应曲面法,实现工艺参数间的协同影响分析,明晰了冲裁工艺参数间的相互作用及其对断面质量的综合效应。基于软件仿真结果确定了保持架窗口冲裁最佳工艺参数组合:冲裁间隙设定为材料厚度的9.31%,冲裁速度调整至103.26 mm/s,凸模刃口圆角半径优化为厚度的1.77%。仿真结果为风电轴承保持架窗口冲裁工艺的优化提供了重要参考,能够大幅提高产品的质量和生产效率。 展开更多
关键词 轴承保持架 deform 响应曲面法 有限元仿真
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基于DEFORM数值模拟的15Cr14Co12Mo5Ni钢齿轮锻造方案优化 被引量:1
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作者 施文鹏 黎恒逸 +2 位作者 张元东 舒勇 王同超 《精密成形工程》 北大核心 2025年第4期78-86,共9页
目的解决15Cr14Co12Mo5Ni钢齿轮锻件易出现粗晶和晶粒度不均匀的问题。方法采用DEFORM数值模拟软件分析15Cr14Co12Mo5Ni钢齿轮成形过程,基于分析结果优化锻件设计方案和锻造工艺方案。结果优化了锻件小端头厚度、中心凹坑尺寸及锻造工... 目的解决15Cr14Co12Mo5Ni钢齿轮锻件易出现粗晶和晶粒度不均匀的问题。方法采用DEFORM数值模拟软件分析15Cr14Co12Mo5Ni钢齿轮成形过程,基于分析结果优化锻件设计方案和锻造工艺方案。结果优化了锻件小端头厚度、中心凹坑尺寸及锻造工艺方案中制坯镦粗高度,使模锻成形过程中齿轮锻件各部位的变形量更加均匀,保证了齿轮小端头难变形区域的变形量≥40%,达到了细化晶粒的目的。结论采用优化后的工艺进行零件试制,结果与DEFORM数值模拟结果相吻合。 展开更多
关键词 15Cr14Co12Mo5Ni钢 deform数值模拟 锻造方案 变形量 晶粒度
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基于Deform的弯链板U弯成形分析及模具参数优化
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作者 汪永明 孙永文 连润柱 《塑性工程学报》 北大核心 2025年第6期79-86,共8页
针对弯链板在U弯成形过程中产生的向外弯曲现象,基于Deform软件在其U弯凹模上分别建立了无预弯块和有预弯块的2组U弯成形有限元仿真模型,仿真结果表明:有预弯块的U弯凹模对工件的向外弯曲变形有着很大的改善作用。建立了5组不同预弯块... 针对弯链板在U弯成形过程中产生的向外弯曲现象,基于Deform软件在其U弯凹模上分别建立了无预弯块和有预弯块的2组U弯成形有限元仿真模型,仿真结果表明:有预弯块的U弯凹模对工件的向外弯曲变形有着很大的改善作用。建立了5组不同预弯块间距的U弯成形有限元仿真模型,分析不同预弯块间距对工件的台阶面间距和平行度的影响,根据仿真结果对比:当预弯块间距为75 mm时,U弯成形件的成形效果最佳,此时其台阶面间距为38.36 mm,台阶面向内弯曲夹角为0.1°。取预弯块间距为最佳值75 mm时,分别研究了不同的U弯间隙与凹模圆角半径对工件U弯成形效果的影响,得出其最佳U弯间隙为5.15 mm,最佳凹模圆角半径为10 mm。基于优化后的模具参数进行了U弯成形实验,依据实验结果,U弯成形件的窄端面间距为27.41~27.47 mm,台阶面间距为38.45~38.61 mm,台阶面夹角为-0.14°~0.27°,实验结果满足U弯成形的工艺要求,有效解决了弯链板在U弯成形过程中的向外弯曲现象。 展开更多
关键词 弯链板 U弯成形 deform仿真 模具改进 参数优化
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Modeling Near-Field Impulsive Waves Generated by Deformable Landslide Using the HBP Model Based on the SPH Method
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作者 WANG Wei WEI Weicheng +4 位作者 CHAI Bo XIA Hao WANG Yang DU Juan LIU Jizhixian 《Journal of Ocean University of China》 CAS CSCD 2024年第2期328-344,共17页
Landslide-generated impulsive waves(LGWs)in reservoir areas can seriously threaten waterway safety as well as hu-man life and properties around the two side slopes.The risk reduction and mitigation of such a hazard re... Landslide-generated impulsive waves(LGWs)in reservoir areas can seriously threaten waterway safety as well as hu-man life and properties around the two side slopes.The risk reduction and mitigation of such a hazard require the accurate prediction of near-field wave characteristics,such as wave amplitude and run-up.However,near-field LGW involves complicated fluid-solid interactions.Furthermore,the wave characteristics are closely related to various aspects,including the geometry and physical features of the slide,river,and body of water.However,the empirical or analytical methods used for rough estimation cannot derive accurate results,especially for deformable landslides,due to their significant geometry changes during the sliding process.In this study,the near-field waves generated by deformable landslides were simulated by smoothed particle hydrodynamics(SPH)based on multi-phase flow.The deformable landslides were generalized as a kind of viscous flow by adopting the Herschel-Bulkley-Papanastasiou(HBP)-based nonNewtonian rheology model.The HBP model is capable of producing deformable landslide dynamics even though the high-speed sliding process is involved.In this study,an idealized experiment case originating from Lituya LGW and a practical case of Gongjiafang LGW were reproduced for verification and demonstration.The simulation results of both cases show satisfactory consistency with the experiment/investigation data in terms of landslide movement and near-field impulsive wave characteristics,thus indicating the applicability and accuracy of the proposed method.Finally,the effects of the HBP model’s rheological parameters on the landslide dynamics and near-field wave characteristics are discussed,providing a parameter calibration method along with sug-gestions for further applications. 展开更多
关键词 deformable landslide impulsive waves NEAR-FIELD SPH nonNewtonian fluids
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Study of deep transportation and plugging performance of deformable gel particles in porous media
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作者 Wen-Jing Zhao Jing Wang +1 位作者 Zhong-Yang Qi Hui-Qing Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期962-973,共12页
Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomen... Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before injection, transport distance, and different injection parameters(injection rate or the diameter ratio of DGP to throat). Likewise, the particle concentration is a function of initial concentration, transport distance, and different injection parameters. These models can be utilized to optimize particle injection parameters, thereby achieving the goal of fine-tuning oil displacement. 展开更多
关键词 Physical simulation deformable gel particle BREAKAGE Particle size Residual resistance coefficient
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A Deformable Network with Attention Mechanism for Retinal Vessel Segmentation
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作者 Xiaolong Zhu Wenjian Li +2 位作者 Weihang Zhang Dongwei Li Huiqi Li 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期186-193,共8页
The intensive application of deep learning in medical image processing has facilitated the advancement of automatic retinal vessel segmentation research.To overcome the limitation that traditional U-shaped vessel segm... The intensive application of deep learning in medical image processing has facilitated the advancement of automatic retinal vessel segmentation research.To overcome the limitation that traditional U-shaped vessel segmentation networks fail to extract features in fundus image sufficiently,we propose a novel network(DSeU-net)based on deformable convolution and squeeze excitation residual module.The deformable convolution is utilized to dynamically adjust the receptive field for the feature extraction of retinal vessel.And the squeeze excitation residual module is used to scale the weights of the low-level features so that the network learns the complex relationships of the different feature layers efficiently.We validate the DSeU-net on three public retinal vessel segmentation datasets including DRIVE,CHASEDB1,and STARE,and the experimental results demonstrate the satisfactory segmentation performance of the network. 展开更多
关键词 retinal vessel segmentation deformable convolution attention mechanism deep learning
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Contact detumbling toward a nutating target through deformable effectors and prescribed performance controller
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作者 ZANG Yue ZHANG Yao +2 位作者 HU Quan LI Mou CHEN Yujun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期753-768,共16页
Detumbling operation toward a rotating target with nutation is meaningful for debris removal but challenging. In this study, a deformable end-effector is first designed based on the requirements for contacting the nut... Detumbling operation toward a rotating target with nutation is meaningful for debris removal but challenging. In this study, a deformable end-effector is first designed based on the requirements for contacting the nutating target. A dual-arm robotic system installed with the deformable end-effectors is modeled and the movement of the end-tips is analyzed. The complex operation of the contact toward a nutating target places strict requirements on control accuracy and controller robustness. Thus, an improvement of the tracking error transformation is proposed and an adaptive sliding mode controller with prescribed performance is designed to guarantee the fast and precise motion of the effector during the contact detumbling.Finally, by employing the proposed effector and the controller,numerical simulations are carried out to verify the effectiveness and efficiency of the contact detumbling toward a nutating target. 展开更多
关键词 nutating target contact detumbling dual-arm space robot deformable end-effector prescribed performance controller
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GAN-DIRNet:A Novel Deformable Image Registration Approach for Multimodal Histological Images
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作者 Haiyue Li Jing Xie +4 位作者 Jing Ke Ye Yuan Xiaoyong Pan Hongyi Xin Hongbin Shen 《Computers, Materials & Continua》 SCIE EI 2024年第7期487-506,共20页
Multi-modal histological image registration tasks pose significant challenges due to tissue staining operations causing partial loss and folding of tissue.Convolutional neural network(CNN)and generative adversarial ne... Multi-modal histological image registration tasks pose significant challenges due to tissue staining operations causing partial loss and folding of tissue.Convolutional neural network(CNN)and generative adversarial network(GAN)are pivotal inmedical image registration.However,existing methods often struggle with severe interference and deformation,as seen in histological images of conditions like Cushing’s disease.We argue that the failure of current approaches lies in underutilizing the feature extraction capability of the discriminator inGAN.In this study,we propose a novel multi-modal registration approach GAN-DIRNet based on GAN for deformable histological image registration.To begin with,the discriminators of two GANs are embedded as a new dual parallel feature extraction module into the unsupervised registration networks,characterized by implicitly extracting feature descriptors of specific modalities.Additionally,modal feature description layers and registration layers collaborate in unsupervised optimization,facilitating faster convergence and more precise results.Lastly,experiments and evaluations were conducted on the registration of the Mixed National Institute of Standards and Technology database(MNIST),eight publicly available datasets of histological sections and the Clustering-Registration-Classification-Segmentation(CRCS)dataset on the Cushing’s disease.Experimental results demonstrate that our proposed GAN-DIRNet method surpasses existing approaches like DIRNet in terms of both registration accuracy and time efficiency,while also exhibiting robustness across different image types. 展开更多
关键词 Histological images registration deformable registration generative adversarial network cushing’s disease machine learning computer vision
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基于Deform的25CrMo4车用钢制花键轴杆零件冷挤压成形工艺研究
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作者 季文骏 龚红英 +2 位作者 兰毅 马骥 廖泽寰 《上海工程技术大学学报》 2025年第2期181-186,共6页
对一种具有复杂外花键的车用轴杆零件挤压工艺展开系统研究,首先对零件进行特性分析,利用Deform软件选取挤压速度、摩擦因数和坯料锥角3个工艺参数进行正交模拟试验,使用极差法确定最优工艺参数为:凸模挤压速度20 mm/s,摩擦因数0.12,坯... 对一种具有复杂外花键的车用轴杆零件挤压工艺展开系统研究,首先对零件进行特性分析,利用Deform软件选取挤压速度、摩擦因数和坯料锥角3个工艺参数进行正交模拟试验,使用极差法确定最优工艺参数为:凸模挤压速度20 mm/s,摩擦因数0.12,坯料锥角15°,零件挤压成形获得最大载荷和最低损伤值,挤压载荷与优化前相比降低26.3%,损伤值则降低81.4%。 展开更多
关键词 花键轴杆零件 冷挤压 正交数值模拟试验 deform软件
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