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Accelerated Elliptical PDE Solver for Computational Fluid Dynamics Based on Configurable U-Net Architecture: Analogy to V-Cycle Multigrid
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作者 Kiran Bhaganagar David Chambers 《Machine Intelligence Research》 2025年第2期324-336,共13页
A configurable U-Net architecture is trained to solve the multi-scale elliptical partial differential equations.The motivation is to improve the computational cost of the numerical solution of Navier-Stokes equations... A configurable U-Net architecture is trained to solve the multi-scale elliptical partial differential equations.The motivation is to improve the computational cost of the numerical solution of Navier-Stokes equations–the governing equations for fluid dynamics.Building on the underlying concept of V-Cycle multigrid methods,a neural network framework using U-Net architecture is optimized to solve the Poisson equation and Helmholtz equations–the characteristic form of the discretized Navier-Stokes equations.The results demonstrate the optimized U-Net captures the high dimensional mathematical features of the elliptical operator and with a better convergence than the multigrid method.The optimal performance between the errors and the FLOPS is the(3,2,5)case with 3 stacks of UNets,with 2 initial features,5 depth layers and with ELU activation.Further,by training the network with the multi-scale synthetic data the finer features of the physical system are captured. 展开更多
关键词 Configurable u-net architecture neural network methods for elliptical equations multi-scale partial differential equations Poisson and Helmholtz equation solvers computational fluid dynamics solutions.
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Chain architecture-engineered artesunate nanoassemblies target LONP1 to induce oxidative damage for enhanced anti-tumor therapy
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作者 Yupeng Wang Xinxin Sun +5 位作者 Jianbin Shi Zhixiao Zhang Jin Sun Cong Luo Zhonggui He Shenwu Zhang 《Chinese Chemical Letters》 2026年第1期497-502,共6页
Despite demonstrating significant anti-tumor potential as an artemisinin derivative,artesunate faces delivery efficiency challenges due to low water solubility and insufficient targeting specificity.To improve the del... Despite demonstrating significant anti-tumor potential as an artemisinin derivative,artesunate faces delivery efficiency challenges due to low water solubility and insufficient targeting specificity.To improve the delivery efficiency,we engineered three artesunate(ART) derivatives,AC_(15)-L(linear),AC_(15)-B(branched),and AC_(15)-C(cyclic) with distinct aliphatic chain architectures.Unexpectedly,we observed that AC_(15)-C exhibited superior cytotoxicity against 4T1 breast cancer cells,and had the highest binding affinity for Lon protease 1(LONP1)(-72.6 kcal/mol).Subsequently,disulfide bond-containing lipid-PEG(DSPESS-PEG2K) modified chain architecture-engineered ART derivatives nanoassemblies(NAs) were developed to mitigate solubility-related limitations while enhancing targeting precision.Molecular docking and experimental validation demonstrated that ART derivatives inhibited LONP1 through hydrophobic interactions while preserved Fe^(2+)-mediated Fenton-like reaction activity.In vitro and in vivo evaluations demonstrated that AC_(15)-C NAs outperformed free ART and other NAs,suppressing 4T1 tumor growth via dual action:LONP1-directed mitochondrial proteostasis collapse and reactive oxygen species(ROS) amplification through Fe^(2+)-ART interactions.This study elucidated a novel anti-tumor mechanism of ART through the rational design of derivatives with spatially configured aliphatic chains,and developed reductionresponsive NAs to provide an advanced delivery strategy. 展开更多
关键词 Chain architecture engineering ART LONP1 NANOASSEMBLIES Cancer therapy
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MimicStudio:One-Stop Development Framework for Dynamic Heterogeneous Redundancy Architecture
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作者 Hu Jingjing Li Yu +3 位作者 Sun Yuanhang Yu Bo Liu Qinrang Wu Jiangxing 《China Communications》 2026年第1期125-139,共15页
Fault-tolerant systems are crucial for ensuring the reliability and availability of missioncritical applications in modern computing environments.The dynamic heterogeneous redundancy(DHR)architecture is a key componen... Fault-tolerant systems are crucial for ensuring the reliability and availability of missioncritical applications in modern computing environments.The dynamic heterogeneous redundancy(DHR)architecture is a key component in constructing fault-tolerant systems,particularly in areas such as national security,power networks,and banking private networks.DHR is transforming the cyberspace security industry chain by accommodating a broader range of applications and increasingly capturing the market.However,the development of applications for DHR architecture encounters challenges due to the complexities of handling heterogeneity,managing dynamism,and maintaining usability.To address these issues,we introduce MimicStudio,a comprehensive development framework with a standardized workflow.To our knowledge,MimicStudio is the first effective solution for DHR software development.We present a detailed implementation of MimicStudio with a heterogeneous microcontroller unit project,encompassing three CPUs with different instruction set architectures.The paper evaluates MimicStudio’s support for essential features,including zero-copy synchronization,parallelized build,multi-core collaborative debugging,and dynamic adjustment of the software system’s structure.Our results show that MimicStudio provides a flexible and efficient solution for supporting the dynamic,heterogeneous,and redundant features of fault-tolerant systems. 展开更多
关键词 cyberspace security development enviroment dynamic heterogeneous redundancy architecture endogenous security MimicStudio
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An ancient super allele of the Vrs1 gene driving the recent success in modern barley improvement through optimising spike architecture
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作者 Jingye Cheng Rui Pan +2 位作者 Wenying Zhang Tianhua He Chengdao Li 《Journal of Integrative Agriculture》 2026年第2期602-609,共8页
Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produc... Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produce three times as many grains as its ancestral two-rowed forms,thus dominating barley cultivation for thousands of years.The deficiens form of the two-rowed type,characterised by extremely suppressed lateral spikelets,has gained dominance over the past few decades in barley-growing regions worldwide.We hypothesised that the absence of lateral spikelets in deficiens barley affects spike architecture and spike-related traits,contributing to its superior yield potential of deficiens barley cultivation.Currently,a deficiens barley variety,RGT Planet,is the most popular barley variety in the world.In this study,we used two F_(2) populations derived from crossing RGT Planet with two canonical two-rowed barley and identified the functional allele Vrs1.t1 associated with deficiens morphology.We observed that the Vrs1.t1 allele may contribute to high yield potential by optimising spike architecture through increased spikelet length,grain number,and grain size.Phylogenetic analysis suggests that the deficiens mutation was likely present from the early stages of barley cultivation in the Fertile Crescent and spread to Ethiopia and beyond with agricultural expansion.We conclude that the ancient deficiens allele Vrs1.t1 has been a critical driver for the recent success of modern barley improvement by optimising spike architecture. 展开更多
关键词 deficiens barley ne mapping Vrs1 gene row types spike architecture yield potential
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A Secured and Continuously Developing Methodology for Breast Cancer Image Segmentation via U-Net Based Architecture and Distributed Data Training
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作者 Rifat Sarker Aoyon Ismail Hossain +1 位作者 M.Abdullah-Al-Wadud Jia Uddin 《Computer Modeling in Engineering & Sciences》 2025年第3期2617-2640,共24页
This research introduces a unique approach to segmenting breast cancer images using a U-Net-based architecture.However,the computational demand for image processing is very high.Therefore,we have conducted this resear... This research introduces a unique approach to segmenting breast cancer images using a U-Net-based architecture.However,the computational demand for image processing is very high.Therefore,we have conducted this research to build a system that enables image segmentation training with low-power machines.To accomplish this,all data are divided into several segments,each being trained separately.In the case of prediction,the initial output is predicted from each trained model for an input,where the ultimate output is selected based on the pixel-wise majority voting of the expected outputs,which also ensures data privacy.In addition,this kind of distributed training system allows different computers to be used simultaneously.That is how the training process takes comparatively less time than typical training approaches.Even after completing the training,the proposed prediction system allows a newly trained model to be included in the system.Thus,the prediction is consistently more accurate.We evaluated the effectiveness of the ultimate output based on four performance matrices:average pixel accuracy,mean absolute error,average specificity,and average balanced accuracy.The experimental results show that the scores of average pixel accuracy,mean absolute error,average specificity,and average balanced accuracy are 0.9216,0.0687,0.9477,and 0.8674,respectively.In addition,the proposed method was compared with four other state-of-the-art models in terms of total training time and usage of computational resources.And it outperformed all of them in these aspects. 展开更多
关键词 Breast cancer u-net distributed training data privacy low-powerful machines
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PM_(2.5) probabilistic forecasting system based on graph generative network with graph U-nets architecture
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作者 LI Yan-fei YANG Rui +1 位作者 DUAN Zhu LIU Hui 《Journal of Central South University》 2025年第1期304-318,共15页
Urban air pollution has brought great troubles to physical and mental health,economic development,environmental protection,and other aspects.Predicting the changes and trends of air pollution can provide a scientific ... Urban air pollution has brought great troubles to physical and mental health,economic development,environmental protection,and other aspects.Predicting the changes and trends of air pollution can provide a scientific basis for governance and prevention efforts.In this paper,we propose an interval prediction method that considers the spatio-temporal characteristic information of PM_(2.5)signals from multiple stations.K-nearest neighbor(KNN)algorithm interpolates the lost signals in the process of collection,transmission,and storage to ensure the continuity of data.Graph generative network(GGN)is used to process time-series meteorological data with complex structures.The graph U-Nets framework is introduced into the GGN model to enhance its controllability to the graph generation process,which is beneficial to improve the efficiency and robustness of the model.In addition,sparse Bayesian regression is incorporated to improve the dimensional disaster defect of traditional kernel density estimation(KDE)interval prediction.With the support of sparse strategy,sparse Bayesian regression kernel density estimation(SBR-KDE)is very efficient in processing high-dimensional large-scale data.The PM_(2.5)data of spring,summer,autumn,and winter from 34 air quality monitoring sites in Beijing verified the accuracy,generalization,and superiority of the proposed model in interval prediction. 展开更多
关键词 PM_(2.5)interval forecasting graph generative network graph u-nets sparse Bayesian regression kernel density estimation spatial-temporal characteristics
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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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Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for Flexible and Stretchable Supercapacitors 被引量:2
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作者 Haonan Zhang Cheng Hao +6 位作者 Tongtong Fu Dian Yu Jane Howe Kaiwen Chen Ning Yan Hao Ren Huamin Zhai 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期447-462,共16页
With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin... With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials. 展开更多
关键词 Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors
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A new wavy-canopy architecture shaped by interlaced application of EDAH increases maize yield and lodging resistance at high density 被引量:2
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作者 Bo Hong Cheng Huang +9 位作者 Zhen-Yuan Chen Hui-Min Chen Jing Wang Xin Liu Zhi-Wei Wang Yi-Hsuan Lin Xian-Min Chen Si Shen Xiao-Gui Liang Shun-Li Zhou 《The Crop Journal》 2025年第2期536-544,共9页
High-density planting increases maize yield but also canopy crowding and stalk lodging.Aiming this contradiction,a wavy canopy was created using interlaced chemical application(IC)of a plant growth retardant at the V1... High-density planting increases maize yield but also canopy crowding and stalk lodging.Aiming this contradiction,a wavy canopy was created using interlaced chemical application(IC)of a plant growth retardant at the V14 stage with three densities(60,000,75,000,and 90,000 plants ha-1,indicated by D1,D2,and D3,respectively)for two seasons.The results showed that the IC-treated wavy canopy featuring both natural height(IC-H)and dwarfed(IC-L)plants,improved light transmission by 8.54%,8.49%,and 16.49%on average than the corresponding controls(CK)at D1,D2,and D3,respectively.The alleviation of canopy crowding stimulated leaf photosynthesis,sugar availability,basal-internode strength,and decreased plant lodging ratios in both IC-H and IC-L,particularly under higher densities.Meanwhile,the IC populations produced significantly higher yield than CK,with an average increase of 3.38%,16.70%,and 15.28%at D1,D2,and D3,respectively.Collectively,this study proposed a new wavy canopy strategy using plant growth retardant to simultaneously increase yield performance and lodging resistance,thus offering a sustainable solution for further development of high-density maize production. 展开更多
关键词 High density Wavy canopy architecture Light intensity Lodging resistance Maize yield
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基于U-Net架构和无人机航拍传感器的公路图像裂缝检测
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作者 陈巍 陈恳 朱文耀 《传感器与微系统》 北大核心 2026年第2期161-166,共6页
针对当前模型对公路裂缝检测不精确的问题,提出了一种基于无人机(UAV)航拍传感器遥感图像的智能检测方法。基于U-Net架构,结合深度可分离残差块(DR-Block)、空间金字塔融合注意力模块(SPFAM)和感受野块(RFB),提出DAR-Unet逐像素裂缝检... 针对当前模型对公路裂缝检测不精确的问题,提出了一种基于无人机(UAV)航拍传感器遥感图像的智能检测方法。基于U-Net架构,结合深度可分离残差块(DR-Block)、空间金字塔融合注意力模块(SPFAM)和感受野块(RFB),提出DAR-Unet逐像素裂缝检测模型。利用无人机采集1 046张高质量公路遥感图像构建专用数据集。在自制数据集上,DAR-Unet的平均交并比(mIoU)和F1分数分别达到76.41%和74.24%,高于主流模型。进一步将模型与无人机集成,构建了公路裂缝检测物联网系统,实际测试表现优异,验证了DAR-Unet在遥感图像公路裂缝检测中的有效性。 展开更多
关键词 无人机 航拍传感器 遥感图像 公路裂缝检测 u-net架构
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基于改进U-Net的人工光植物工厂生菜图像分割方法
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作者 李文豪 金文帅 +3 位作者 高晟 薛岳 毛罕平 左志宇 《农机化研究》 北大核心 2026年第6期157-163,共7页
针对植物工厂内作物在人工光环境下图像分割精度不足的问题,提出了一种改进的U-Net神经网络模型,以实现对作物图像的高精度分割。首先通过对比试验,系统比较了传统图像分割方法(如阈值、聚类和区域等)与神经网络方法在人工光环境下的分... 针对植物工厂内作物在人工光环境下图像分割精度不足的问题,提出了一种改进的U-Net神经网络模型,以实现对作物图像的高精度分割。首先通过对比试验,系统比较了传统图像分割方法(如阈值、聚类和区域等)与神经网络方法在人工光环境下的分割效果,结果表明:与传统方法相比,U-Net神经网络在分割精度和模型稳定性方面具有明显优势。然而,进一步分析U-Net模型的分割结果发现,其在复杂光照条件下的分割精度和泛化能力仍有提升空间,主要体现在边界细节处理和小目标分割的准确性不足。为此,针对性地提出3种改进策略:一是通过数据增强技术扩展训练数据集,以提升模型的鲁棒性;二是对U-Net模型的结构进行优化,改进金字塔结构以增强多尺度特征融合能力;三是采用坐标注意力机制,有效提升模型对目标区域的聚焦能力,特别是在背景复杂或光线不均的情况下。基于此,进行试验验证,结果表明:结合改进金字塔结构和坐标注意力机制的U-Net模型在分割平均精确率和平均交并比上分别达到98.19%和96.86%,相比原始U-Net模型分别提高了4.01、3.02个百分点。所提方法显著改善了人工光环境下对植物工厂作物的图像分割性能,为植物工厂内作物生长监测与精准信息采集提供了技术支持,同时为未来智能农业领域的相关研究奠定了基础。 展开更多
关键词 生菜图像分割 植物工厂 人工光 改进u-net 注意力机制 神经网络
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基于改进U-Net的冷冻电镜图像去噪方法
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作者 邓竞 曾安 金亮 《计算机应用与软件》 北大核心 2026年第1期241-248,共8页
针对冷冻电镜图像信噪比极低,并且现有去噪方法不能有效去掉复杂噪声的问题,提出一种基于改进U-Net的冷冻电镜图像去噪方法。改进方法用FCN(Fully Convolutional Networks)搭建噪声映射模块,并在原始U-Net网络中嵌入多尺度联接和宽激活... 针对冷冻电镜图像信噪比极低,并且现有去噪方法不能有效去掉复杂噪声的问题,提出一种基于改进U-Net的冷冻电镜图像去噪方法。改进方法用FCN(Fully Convolutional Networks)搭建噪声映射模块,并在原始U-Net网络中嵌入多尺度联接和宽激活密集残差块,既能提高网络的泛化能力又使模型能更好地提取和恢复特征信息,从而实现高质量的冷冻电镜图像去噪;全变差损失函数的引入用来保护输出图像中的颗粒细节信息。实验结果表明,相较于对比方法,该方法在有效去除背景噪声同时能更好地恢复颗粒细节,信噪比(Signal to Noise Ratio,SNR)也是最优,并且颗粒挑选阳性数量也得到提升。 展开更多
关键词 图像去噪 冷冻电镜 u-net FCN
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Optimization method of heat transfer architecture for aircraft fuel thermal management systems 被引量:1
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作者 Jiangtao XU Haotian TAN +3 位作者 Jitao WU Jiayi HAN Sirong SU Hongqing LYU 《Chinese Journal of Aeronautics》 2025年第8期300-312,共13页
Modern aircraft tend to use fuel thermal management systems to cool onboard heat sources.However,the design of heat transfer architectures for fuel thermal management systems relies on the experience of the engineers ... Modern aircraft tend to use fuel thermal management systems to cool onboard heat sources.However,the design of heat transfer architectures for fuel thermal management systems relies on the experience of the engineers and lacks theoretical guidance.This paper proposes a concise graph representation method based on graph theory for fuel thermal management systems,which can represent all possible connections between subsystems.A generalized optimization algorithm is proposed for fuel thermal management system architecture to minimize the heat sink.This algorithm can autonomously arrange subsystems with heat production differences and efficiently utilize the architecture of the fuel heat sink.At the same time,two evaluation indices are proposed from the perspective of subsystems.These indices intuitively and clearly show that the reason for the high efficiency of heat sink utilization is the balanced and moderate cooling of each subsystem and verify the rationality of the architecture optimization method.A set of simulations are also conducted,which demonstrate that the fuel tank temperature has no effect on the performance of the architecture.This paper provides a reference for the architectural design of aircraft fuel thermal management systems.The metrics used in this paper can also be utilized to evaluate the existing architecture. 展开更多
关键词 Fuel thermal management systems architecture optimization Graph theory Fuel heat sink Fuel distribution
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Progradational sequence stratigraphic architecture of the Triassic Yanchang Formation and a case study of Qingcheng Oilfield,Ordos Basin,NW China 被引量:1
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作者 HUI Xiao HOU Yunchao +2 位作者 QU Tong ZHANG Jie YANG Zhi 《Petroleum Exploration and Development》 2025年第5期1164-1178,共15页
To address the discrepancies between well and seismic data in stratigraphic correlation of the Triassic Yanchang Formation in the Ordos Basin,NW China,traditional stratigraphic classification schemes,the latest 3D sei... To address the discrepancies between well and seismic data in stratigraphic correlation of the Triassic Yanchang Formation in the Ordos Basin,NW China,traditional stratigraphic classification schemes,the latest 3D seismic and drilling data,and reservoir sections are thoroughly investigated.Guided by the theory of sequence stratigraphy,the progradational sequence stratigraphic framework of the Yanchang Formation is systematically constructed to elucidate new deposition mechanisms in the depressed lacustrine basin,and it has been successfully applied to the exploration and development practices in the Qingcheng Oilfield.Key findings are obtained in three aspects.First,the seismic progradational reflections,marker tuff beds,and condensed sections of flooding surfaces in the Yanchang Formation are consistent and isochronous.Using flooding surface markers as a reference,a progradational sequence stratigraphic architecture is reconstructed for the middle-upper part of Yanchang Formation,and divided into seven clinoform units(CF1-CF7).Second,progradation predominantly occurs in semi-deep to deep lake environments,with the depositional center not always coinciding with the thickest strata.The lacustrine basin underwent an evolution of“oscillatory regression-progradational infilling-multi-phase superimposition”.Third,the case study of Qingcheng Oilfield reveals that the major pay zones consist of“isochronous but heterochronous”gravity-flow sandstone complexes.Guided by the progradational sequence stratigraphic architecture,horizontal well oil-layer penetration rates remain above 82%.The progradational sequence stratigraphic architecture and associated geological insights are more consistent with the sedimentary infilling mechanisms of large-scale continental depressed lacustrine basins and actual drilling results.The research results provide crucial theoretical and technical support for subsequent refined exploration and development of the Yanchang Formation,and are expected to offer a reference for research and production practice in similar continental lacustrine basins. 展开更多
关键词 progradational sequence stratigraphic architecture CLINOFORM flooding surface continental depression lacustrine basin Ordos Basin TRIASSIC Yanchang Formation
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基于改进U-Net与RGB-D图像的青花椒枝条“下桩”剪切点定位
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作者 蒲应俊 张文州 +3 位作者 李金广 赵立军 陈子文 杨明金 《农业工程学报》 北大核心 2026年第1期160-170,共11页
青花椒枝条“下桩”是通过剪下带鲜果的枝条并保留一定长度短桩的采摘收获方法。为实现青花椒采摘机器人精准识别枝条并确定最佳剪切点以达到高效“下桩”作业,该研究提出了一种基于U-Net深度学习网络和RGB-D相机相结合的青花椒主枝“... 青花椒枝条“下桩”是通过剪下带鲜果的枝条并保留一定长度短桩的采摘收获方法。为实现青花椒采摘机器人精准识别枝条并确定最佳剪切点以达到高效“下桩”作业,该研究提出了一种基于U-Net深度学习网络和RGB-D相机相结合的青花椒主枝“下桩”剪切点定位方法。首先,通过改进传统U-Net模型,将其主干网络替换为嵌入CA注意力机制的ResNet50网络,同时在U-Net模型的特征拼接阶段中增加SE注意力机制,从而构建针对青花椒主枝和树干的分割模型。然后,将分割后的图像利用二值化与骨架线提取方法得到主枝中心线,结合RGB-D相机的深度信息与OpenCV图像处理算法,完成世界坐标系与像素坐标系间长度的映射。随后,将短桩预设的40 mm长度从世界坐标系映射至RGB图像中的像素长度,最终确定每根主枝的“下桩”剪切点位置。试验结果表明,改进后的U-Net模型在分割性能上优于DeeplabV3+和PSPNet,平均交并比(MIoU)、平均像素准确率(mPA)和召回率(recall)分别达到87.58%、93.76%和96.24%。在晴天顺光、逆光及阴天条件下,“下桩”剪切点识别定位的成功率分别达到90.81%、84.88%、80.52%。采摘点定位试验中,定位成功率为90%,单根花椒枝平均识别过程耗时1.93 s。该研究结果可为青花椒采摘机器人“下桩”采收提供技术支撑。 展开更多
关键词 图像处理 青花椒 采摘 u-net网络模型 下桩采摘法 剪切点定位
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Architecture to Secure Electrical Control System in Cyber-Physical System
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作者 Depeng Li 《Journal of Information Security》 2025年第1期149-157,共9页
It’s possible for malicious operators to seize hold of electrical control systems, for instance, the engine control unit of driverless vehicles, from various vectors, e.g. autonomic control system, remote vehicle acc... It’s possible for malicious operators to seize hold of electrical control systems, for instance, the engine control unit of driverless vehicles, from various vectors, e.g. autonomic control system, remote vehicle access, or human drivers. To mitigate potential risks, this paper provides the inauguration study by proposing a theoretical framework in the physical, human and cyber triad. Its goal is to, at each time point, detect adversary control behaviors and protect control systems against malicious operations via integrating a variety of methods. This paper only proposes a theoretical framework which tries to indicate possible threats. With the support of the framework, the security system can lightly reduce the risk. The development and implementation of the system are out of scope. 展开更多
关键词 architecture Control System FRAMEWORK
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The Evolution of Vernacular Architecture in Siwa Oasis,Egypt
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作者 Riham Mohammed Jaber Ahmed 《Journal of Civil Engineering and Architecture》 2025年第6期288-295,共8页
Not always climate and cultural contexts are discussed at the forefront of architectural discussions on traditional or vernacular architecture,nevertheless,the construction material also plays a significant part in de... Not always climate and cultural contexts are discussed at the forefront of architectural discussions on traditional or vernacular architecture,nevertheless,the construction material also plays a significant part in defining places’architectural languages.Building from the local materials is an essential ingredient of the local distinctiveness,whilst forming the architectural grand gesture in its context.In Siwa oasis,salt architecture has formed that architectural grand gesture.The vernacular vocabularies adopted by old Bedouins using salt bricks generated Siwa’s unique spirit.In this paper,some examples are illustrated based on a series of site visits to three main sites in Siwa,namely:Old Shali,Abu Shuruf,and Aghourmy.This shows the evolution of Siwa’s vernacular architecture and the role of the architectural language or detrimental effect on the overall quality of architecture.From the site visits,it was observed that building with the traditional technique is now becoming abandoned in Siwa,explained by the local builders to be due to the huge costs required;forcing them to shifting to modern architecture.The influx to building using modern techniques has led to a significant transformation in the urban morphology and spirit of Siwa.Herein lies the scope of this paper:to discuss the impact of the evolution of vernacular architecture on the overall quality of architecture in Siwa and thus identifying the problems which will lead to policy formulation and guidelines for the redevelopment of Siwa in order to“revitalize/resuscitate”its vernacular style accordingly. 展开更多
关键词 Vernacular architecture Neo-vernacular architecture Siwa EGYPT
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基于级联YOLO和U-Net的腰椎图像分割模型YOLOMACR-Net
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作者 何致远 汪灿华 《现代信息科技》 2026年第2期91-97,共7页
针对腰椎MRI图像中椎体目标形态多变、背景解剖结构复杂及组织间对比度低,导致现有方法出现关键结构漏检、边缘分割粗糙及参数冗余等问题,提出一种融合多尺度特征增强与级联架构的轻量化腰椎分割模型YOLOMACR-Net。首先,在YOLOv5n框架... 针对腰椎MRI图像中椎体目标形态多变、背景解剖结构复杂及组织间对比度低,导致现有方法出现关键结构漏检、边缘分割粗糙及参数冗余等问题,提出一种融合多尺度特征增强与级联架构的轻量化腰椎分割模型YOLOMACR-Net。首先,在YOLOv5n框架中设计多尺度非对称空洞残差模块(MACR),利用非对称卷积适配椎体几何特征,扩大感受野以解决单阶段检测的漏检问题;其次,构建“定位-分割”级联架构,利用定位结果剔除背景噪声,引导U-Net进行精细化分割。在公开数据集上的实验结果表明,YOLOMACR-Net的结构捕获率(SCR)达到100%,mIoU、Dice系数和HD95分别达到88.17%、93.71%和3.37 mm,且参数量仅为1.65M。结果证明该模型能有效整合多尺度信息,在保持轻量化的同时显著提升了复杂场景下的分割精度。 展开更多
关键词 医学图像分割 深度学习 YOLO MACR u-net
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