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Review of Artificial Intelligence for Oil and Gas Exploration: Convolutional Neural Network Approaches and the U-Net 3D Model
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作者 Weiyan Liu 《Open Journal of Geology》 CAS 2024年第4期578-593,共16页
Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Ou... Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Our review traces the evolution of CNN, emphasizing the adaptation and capabilities of the U-Net 3D model in automating seismic fault delineation with unprecedented accuracy. We find: 1) The transition from basic neural networks to sophisticated CNN has enabled remarkable advancements in image recognition, which are directly applicable to analyzing seismic data. The U-Net 3D model, with its innovative architecture, exemplifies this progress by providing a method for detailed and accurate fault detection with reduced manual interpretation bias. 2) The U-Net 3D model has demonstrated its superiority over traditional fault identification methods in several key areas: it has enhanced interpretation accuracy, increased operational efficiency, and reduced the subjectivity of manual methods. 3) Despite these achievements, challenges such as the need for effective data preprocessing, acquisition of high-quality annotated datasets, and achieving model generalization across different geological conditions remain. Future research should therefore focus on developing more complex network architectures and innovative training strategies to refine fault identification performance further. Our findings confirm the transformative potential of deep learning, particularly CNN like the U-Net 3D model, in geosciences, advocating for its broader integration to revolutionize geological exploration and seismic analysis. 展开更多
关键词 Deep Learning Convolutional Neural Networks (CNN) Seismic Fault Identification u-net 3D model Geological Exploration
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基于曼哈顿距离自注意力机制的 U-Net3+图像分割
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作者 张志玮 叶曦 杨志红 《江汉大学学报(自然科学版)》 2024年第2期56-67,共12页
目前主流图像分割算法在分割边界上对特征相似而类别不同的像素鉴别能力不佳,从而影响了分割精度。设计了一种基于曼哈顿距离自注意力机制的U-Net3+图像分割算法,通过关注不同特征点之间信息表征的差异程度来对大范围上下文信息关系进... 目前主流图像分割算法在分割边界上对特征相似而类别不同的像素鉴别能力不佳,从而影响了分割精度。设计了一种基于曼哈顿距离自注意力机制的U-Net3+图像分割算法,通过关注不同特征点之间信息表征的差异程度来对大范围上下文信息关系进行建模,增强算法对特征相似而类别不同的像素的鉴别能力和对全局关系的学习能力;再通过U-Net3+的全尺度跳跃连接结构将不同尺度的特征相融合,为算法提供更多尺度的上下文信息,使分割算法兼顾细节信息和全局关系。使用COVID-19 CT数据集对该算法进行实验测试,结果表明,引入基于曼哈顿距离自注意力机制后U-Net3+的Dice和IoU指标分别提升了2.79%和3.17%,对比使用多头自注意力机制的U-Net3+分别提升了1.06%和1.02%,证明了该算法的有效性和优越性。 展开更多
关键词 图像分割 自注意力机制 曼哈顿距离 u-net3+
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3D bioprinting of in vitro porous hepatoma models:establishment,evaluation,and anticancer drug testing
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作者 Xiaoyuan Wang Zixian Liu +7 位作者 Qianqian Duan Boye Zhang Yanyan Cao Zhizhong Shen Meng Li Yanfeng Xi Jianming Wang Shengbo Sang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第2期137-152,共16页
Traditional tumor models do not tend to accurately simulate tumor growth in vitro or enable personalized treatment and are particularly unable to discover more beneficial targeted drugs.To address this,this study desc... Traditional tumor models do not tend to accurately simulate tumor growth in vitro or enable personalized treatment and are particularly unable to discover more beneficial targeted drugs.To address this,this study describes the use of threedimensional(3D)bioprinting technology to construct a 3D model with human hepatocarcinoma SMMC-7721 cells(3DP-7721)by combining gelatin methacrylate(GelMA)and poly(ethylene oxide)(PEO)as two immiscible aqueous phases to form a bioink and innovatively applying fluorescent carbon quantum dots for long-term tracking of cells.The GelMA(10%,mass fraction)and PEO(1.6%,mass fraction)hydrogel with 3:1 volume ratio offered distinct pore-forming characteristics,satisfactorymechanical properties,and biocompatibility for the creation of the 3DP-7721 model.Immunofluorescence analysis and quantitative real-time fluorescence polymerase chain reaction(PCR)were used to evaluate the biological properties of the model.Compared with the two-dimensional culture cell model(2D-7721)and the 3D mixed culture cell model(3DM-7721),3DP-7721 significantly improved the proliferation of cells and expression of tumor-related proteins and genes.Moreover,we evaluated the differences between the three culture models and the effectiveness of antitumor drugs in the three models and discovered that the efficacy of antitumor drugs varied because of significant differences in resistance proteins and genes between the three models.In addition,the comparison of tumor formation in the three models found that the cells cultured by the 3DP-7721 model had strong tumorigenicity in nude mice.Immunohistochemical evaluation of the levels of biochemical indicators related to the formation of solid tumors showed that the 3DP-7721 model group exhibited pathological characteristics of malignant tumors,the generated solid tumors were similar to actual tumors,and the deterioration was higher.This research therefore acts as a foundation for the application of 3DP-7721 models in drug development research. 展开更多
关键词 3D bioprinting Hepatoma tumor models Drug screening Antitumor drug development
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3D Road Network Modeling and Road Structure Recognition in Internet of Vehicles
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作者 Dun Cao Jia Ru +3 位作者 Jian Qin Amr Tolba Jin Wang Min Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1365-1384,共20页
Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transp... Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transportationsystem. The movement of vehicles and the three-dimensional (3D) nature of the road network cause the topologicalstructure of IoV to have the high space and time complexity.Network modeling and structure recognition for 3Droads can benefit the description of topological changes for IoV. This paper proposes a 3Dgeneral roadmodel basedon discrete points of roads obtained from GIS. First, the constraints imposed by 3D roads on moving vehicles areanalyzed. Then the effects of road curvature radius (Ra), longitudinal slope (Slo), and length (Len) on speed andacceleration are studied. Finally, a general 3D road network model based on road section features is established.This paper also presents intersection and road section recognition methods based on the structural features ofthe 3D road network model and the road features. Real GIS data from a specific region of Beijing is adopted tocreate the simulation scenario, and the simulation results validate the general 3D road network model and therecognitionmethod. Therefore, thiswork makes contributions to the field of intelligent transportation by providinga comprehensive approach tomodeling the 3Droad network and its topological changes in achieving efficient trafficflowand improved road safety. 展开更多
关键词 Internet of vehicles road networks 3D road model structure recognition GIS
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Rainfall-triggered waste dump instability analysis based on surface 3D deformation in physical model test
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作者 LI Hanlin JIN Xiaoguang +2 位作者 HE Jie XUE Yunchuan YANG Zhongping 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1549-1563,共15页
Landslide is the second largest natural disaster after earthquake. It is of significance to study the evolution laws and failure mechanism of landslides based on its surface 3D deformation information. Based on the ra... Landslide is the second largest natural disaster after earthquake. It is of significance to study the evolution laws and failure mechanism of landslides based on its surface 3D deformation information. Based on the rainfall-triggered waste dump instability model test, we studied the failure mechanisms of the waste dump by integrating surface deformation and internal slope stress and proposed novel parameters for identifying landslide stability. We developed a noncontact measurement device, which can obtain millimeter-level 3D deformation data for surface scene in physical model test;Then we developed the similar materials and established a test model for a waste dump. Based on the failure characteristics of slope surface, internal stress of slope body and displacement contours during the whole process, we divided the slope instability process in model test into four stages: rainfall infiltration and surface erosion, shallow sliding, deep sliding, and overall instability. Based on the obtained surface deformation data, we calculated the volume change during slope instability process and compared it with the point displacement on slope surface. The results showed that the volume change can not only reflect the slow-ultra acceleration process of slope failure, but also fully reflect the above four stages and reduce the fluctuations caused by random factors. Finally, this paper proposed two stability identification parameters: the volume change rate above the slip surface and the relative velocity of volume change rate. According to the calculation of these two parameters in model test, they can be used for study the deformation and failure mechanism of slope stability. 展开更多
关键词 Waste dump stability Physical model test Surface 3D deformation Stability identification
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Exploring mechanism of hidden,steep obliquely inclined bedding landslides using a 3DEC model:A case study of the Shanyang landslide in Shaanxi Province,China
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作者 Jia-yun Wang Zi-long Wu +3 位作者 Xiao-ya Shi Long-wei Yang Rui-ping Liu Na Lu 《China Geology》 CAS CSCD 2024年第2期303-314,I0001-I0003,共15页
Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This... Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This phenomenon has become a focal point in landslide research.Yet,there is a lack of studies on the failure modes and mechanisms of hidden,steep obliquely inclined bedding slopes.This study investigated the Shanyang landslide in Shaanxi Province,China.Using field investigations,laboratory tests of geotechnical parameters,and the 3DEC software,this study developed a numerical model of the landslide to analyze the failure process of such slopes.The findings indicate that the Shanyang landslide primarily crept along a weak interlayer under the action of gravity.The landslide,initially following a dip angle with the support of a stable inclined rock mass,shifted direction under the influence of argillization in the weak interlayer,moving towards the apparent dip angle.The slide resistance effect of the karstic dissolution zone was increasingly significant during this process,with lateral friction being the primary resistance force.A reduction in the lateral friction due to karstic dissolution made the apparent dip sliding characteristics of the Shanyang landslide more pronounced.Notably,deformations such as bending and uplift at the slope’s foot suggest that the main slide resistance shifts from lateral friction within the karstic dissolution zone to the slope foot’s resistance force,leading to the eventual buckling failure of the landslide.This study unveils a novel failure mode of apparent dip creep-buckling in the Shanyang landslide,highlighting the critical role of lateral friction from the karstic dissolution zone in its failure mechanism.These insights offer a valuable reference for mitigating risks and preventing disasters related to obliquely inclined bedding landslides. 展开更多
关键词 LANDSLIDE Steep obliquely inclined bedding slope Failure mode Failure mechanism Apparent dip creep-buckling Lateral friction 3DEC model Landslide numerical model Geological hazards survey engineering
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Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils
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作者 Belemdara Dingamadji Hilaire Mbaïnaïbeye Jérôme Guidkaya Golam 《Journal of Electromagnetic Analysis and Applications》 2024年第2期11-23,共13页
The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the tw... The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet. 展开更多
关键词 modelLING 3D Finite Elements Magnetic Flux Hybrid Stepping Motor
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A 3D attention U-Net network and its application in geological model parameterization
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作者 LI Xiaobo LI Xin +4 位作者 YAN Lin ZHOU Tenghua LI Shunming WANG Jiqiang LI Xinhao 《Petroleum Exploration and Development》 2023年第1期183-190,共8页
To solve the problems of convolutional neural network–principal component analysis(CNN-PCA)in fine description and generalization of complex reservoir geological features,a 3D attention U-Net network was proposed not... To solve the problems of convolutional neural network–principal component analysis(CNN-PCA)in fine description and generalization of complex reservoir geological features,a 3D attention U-Net network was proposed not using a trained C3D video motion analysis model to extract the style of a 3D model,and applied to complement the details of geologic model lost in the dimension reduction of PCA method in this study.The 3D attention U-Net network was applied to a complex river channel sandstone reservoir to test its effects.The results show that compared with CNN-PCA method,the 3D attention U-Net network could better complement the details of geological model lost in the PCA dimension reduction,better reflect the fluid flow features in the original geologic model,and improve history matching results. 展开更多
关键词 reservoir history matching geological model parameterization deep learning attention mechanism 3D u-net
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D model Schrödinger Equation RMS Klein GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow ATTRACTION REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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采用带注意力机制3D U-Net网络的地质模型参数化技术 被引量:1
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作者 李小波 李欣 +4 位作者 闫林 周腾骅 李顺明 王继强 李心浩 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2023年第1期167-173,共7页
针对卷积神经网络增强的主成分分析技术(CNN-PCA)这种地质模型参数化技术在油藏复杂地质特征刻画精度和泛化能力方面存在的问题,不使用预训练好的C3D视频动作分析模型来提取三维模型风格特征,而使用新的损失函数并引入一种带注意力机制... 针对卷积神经网络增强的主成分分析技术(CNN-PCA)这种地质模型参数化技术在油藏复杂地质特征刻画精度和泛化能力方面存在的问题,不使用预训练好的C3D视频动作分析模型来提取三维模型风格特征,而使用新的损失函数并引入一种带注意力机制的3D U-Net网络来补全主成分分析方法(PCA)降维过程中丢失的地质模型细节信息,并以一个复合河道砂体油藏为例进行了应用效果分析。研究表明,与CNN-PCA技术相比,采用带注意力机制的3DU-Net网络能够更好地补全PCA降维过程中丢失的地质模型细节信息,在反映原始地质模型的流动特性方面具有更好的效果,并能改善油藏历史拟合的技术效果。 展开更多
关键词 油藏历史拟合 地质模型参数化 深度学习 注意力机制 3D u-net网络
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基于YOLOv5和U-Net3+的桥梁裂缝智能识别与测量 被引量:9
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作者 余加勇 刘宝麟 +2 位作者 尹东 高文宇 谢义林 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2023年第5期65-73,共9页
为了克服传统数字图像处理方法进行桥梁裂缝识别时面临的效率低、效果不佳等问题,提出了集成深度学习YOLOv5和U-Net3+算法的一体化桥梁裂缝智能检测方法.通过调整算法宽度和深度参数,优化边界框损失函数,构建基于YOLOv5目标检测算法的... 为了克服传统数字图像处理方法进行桥梁裂缝识别时面临的效率低、效果不佳等问题,提出了集成深度学习YOLOv5和U-Net3+算法的一体化桥梁裂缝智能检测方法.通过调整算法宽度和深度参数,优化边界框损失函数,构建基于YOLOv5目标检测算法的裂缝识别定位模型,实现桥梁裂缝快速识别与定位;引入结合深度监督策略及预测输出模块的U-Net3+图像分割算法,训练并构建桥梁裂缝高效分割模型,实现像素级裂缝智能化提取;建立结合连通域去噪、边缘检测、形态学处理的八方向裂缝宽度测量法,基于U-Net3+裂缝分割结果实现裂缝形态及宽度高精度测量;利用LabelImg图像标注软件制作包含4414张图像的裂缝识别定位模型训练数据集;利用LabelImg图像标注软件及CFD数据集制作包含908张图像的裂缝分割模型训练数据集;利用无人机航拍的485张5280×2970 pixels桥梁索塔裂缝图像,来制作裂缝智能检测模型的测试对象.将所提出的裂缝检测方法应用于上述裂缝测试对象,其裂缝识别定位准确率91.55%、召回率95.15%、F1分数93.32%,裂缝分割准确率93.02%、召回率92.22%、F1分数92.22%.结果表明,基于YOLOv5与U-Net3+的桥梁裂缝智能检测方法,可实现桥梁裂缝高效率、高精度、智能化检测,具有较强的研究价值和广泛的应用前景. 展开更多
关键词 桥梁工程 裂缝检测 裂缝测量 YOLOv5 u-net3+ 无人机
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基于深层多尺度聚合3D U-Net的肾脏与肾肿瘤分割方法
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作者 张芳 郝思敏 耿磊 《天津工业大学学报》 CAS 北大核心 2023年第6期84-90,共7页
针对电子计算机断层扫描(CT)图像中肾肿瘤形态复杂多变、肿瘤目标小、肿瘤边缘复杂等问题,提出了深层多尺度聚合3D U-Net网络分割模型。该模型在U-Net++基础上新增了3个下采样操作,利用密集嵌套的3D U-Net和解码器层的跳跃连接以及各层... 针对电子计算机断层扫描(CT)图像中肾肿瘤形态复杂多变、肿瘤目标小、肿瘤边缘复杂等问题,提出了深层多尺度聚合3D U-Net网络分割模型。该模型在U-Net++基础上新增了3个下采样操作,利用密集嵌套的3D U-Net和解码器层的跳跃连接以及各层级3D U-Net子网络之间的跳跃连接,促进各个层级和各个尺度的特征信息融合,增强了对细节特征的提取能力,从而提升了对小尺度肾肿瘤和肿瘤边缘的分割精度。实验结果表明:该模型能够准确分割边缘复杂以及尺度较小的肾肿瘤,在KiTS19公开数据集上进行评估,本文模型对肾脏分割的Dise系数为0.968 2,对肿瘤分割的Dise系数为0.790 8,分割性能良好。 展开更多
关键词 肾肿瘤 自动分割 CT图像 3D u-net 深层多尺度聚合
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沈阳市O_(3)与PM_(2.5)关系及污染主控因素分析
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作者 洪也 马雁军 +5 位作者 苏枞枞 王扬锋 任万辉 王继康 王东东 徐晓斌 《环境科学研究》 CAS CSCD 北大核心 2024年第3期455-468,共14页
PM_(2.5)与O_(3)的协同控制是空气质量持续改善的关键所在,厘清PM_(2.5)与O_(3)的关系,识别O_(3)主控因素以及量化气象和人为排放贡献是实施二者协同控制的基础.本研究基于沈阳市大气复合立体超级站2019−2022年地面观测数据,分析PM_(2.5... PM_(2.5)与O_(3)的协同控制是空气质量持续改善的关键所在,厘清PM_(2.5)与O_(3)的关系,识别O_(3)主控因素以及量化气象和人为排放贡献是实施二者协同控制的基础.本研究基于沈阳市大气复合立体超级站2019−2022年地面观测数据,分析PM_(2.5)和O_(3)协同关系及成因;利用逐步回归模型得到影响O_(3)变化的主控因素,并估算各气象因素对O_(3)的贡献.结果表明:①沈阳市2019−2022年夏季PM_(2.5)浓度与O_(3)浓度呈正相关,有明显的协同增长效应,其余三季均呈明显负相关.究其原因,主要是由于夏季高温和高太阳辐射条件利于大气光化学反应,促进了O_(3)、PM_(2.5)中二次无机成分〔主要是硫酸盐(SO_(4)^(2−))、硝酸盐(NO_(3)−)和铵盐(NH_(4)^(+)),简称“SNA”〕共同增长所致;而冬季高排放和高大气稳定度等气象条件利于SNA和二次有机碳(SOC)非均相生成,但弱太阳辐射和低温等条件不利于O_(3)光化学生成,加之高NO的滴定效应,使SNA和SOC浓度均与O_(3)浓度呈负相关.②在观测的相关污染物和气象因子中,过氧乙酰硝酸酯(PAN)与O_(3)浓度的关系最为密切,尤其在夏季.③气象因素中,O_(3)浓度与气温高度相关,与风速也呈正相关,而与相对湿度则在各季节均呈负相关.冬、春、秋三季PM_(2.5)均对O_(3)起抑制作用,冬季尤为突出.在高浓度O_(3)污染(O_(3)浓度>160μg/m^(3))过程中,主控因素中气温和风速的抬升促进O_(3)浓度升高,而高NO2和相对湿度(RH)则有利于降低O_(3)浓度.在2019−2022年高浓度O_(3)污染过程中,气象因素对沈阳市O_(3)浓度变化的贡献高于O_(3)前体物排放的贡献,总贡献为57μg/m^(3),对污染形成起着主导作用. 展开更多
关键词 PM_(2.5) O_(3) PM_(2.5)与O_(3)协同作用 气象因素 逐步回归模型
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基于改进的3D U-Net骨盆CT影像多类分割 被引量:1
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作者 刘志 李兴春 +4 位作者 郑斌 谢小山 肖林 李迎新 秦传波 《现代电子技术》 2023年第3期47-51,共5页
骨盆CT影像精确分割是骨盆骨疾病的临床诊断和手术规划中非常重要的环节。针对目前2D骨盆分割方法对三维医学影像进行切片处理时损失空间信息的问题,提出了改进3D U-Net网络实现对骨盆CT影像3D自动分割。实验数据为公开数据集CTPelvic1K... 骨盆CT影像精确分割是骨盆骨疾病的临床诊断和手术规划中非常重要的环节。针对目前2D骨盆分割方法对三维医学影像进行切片处理时损失空间信息的问题,提出了改进3D U-Net网络实现对骨盆CT影像3D自动分割。实验数据为公开数据集CTPelvic1K共1184名患者骨盆CT影像,其中包含骶骨、左髋骨、右髋骨和腰椎四个部位标签。以3D U-Net骨干网络为基础,结合自注意力机制提出3D多类分割模型3D Trans U-Net,并使用迁移学习训练3D U-Net、V-Net、Attention U-Net作为对照实验。实验结果表明:3D Trans U-Net在测试集上整个骨盆区域、骶骨、左髋骨、右髋骨、腰椎Dice系数分别达到97.99%,96.70%,97.96%,97.95%,96.89%;Dice系数、豪斯多夫距离等评价指标均优于现有经典网络3D U-Net、V-Net、Attention U-Net。因此,改进的3D Trans U-Net对骨盆不同部位具有较好的分割效果,为精准医治骨盆骨疾病提供了一条有效的技术途径。 展开更多
关键词 骨盆CT影像 多类分割 3D Trans u-net 数据采集 自注意力 实验测试
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基于3D U-Net和DTI模型约束的扩散张量场估计方法 被引量:1
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作者 麦兆华 李嘉龙 +1 位作者 冯衍秋 张鑫媛 《南方医科大学学报》 CAS CSCD 北大核心 2023年第7期1224-1232,共9页
目的为从少量的低信噪比扩散加权(DW)图像中估计得到准确的扩散张量成像(DTI)量化参数,本文提出一种基于3D U-Net和DTI模型约束的扩散张量场估计网络(3D DTI-Unet)。方法3D DTI-Unet的输入为有噪声的扩散磁共振成像(dMRI)数据(包含1幅... 目的为从少量的低信噪比扩散加权(DW)图像中估计得到准确的扩散张量成像(DTI)量化参数,本文提出一种基于3D U-Net和DTI模型约束的扩散张量场估计网络(3D DTI-Unet)。方法3D DTI-Unet的输入为有噪声的扩散磁共振成像(dMRI)数据(包含1幅非扩散加权图像与6幅不同扩散编码方向的DW图像),通过3D U-Net网络预测得到降噪后的非扩散加权图像以及准确的扩散张量场,并通过DTI模型重建得到dMRI数据,将其与dMRI数据的真实值进行比较来优化网络,从而保证dMRI数据与扩散张量场的物理模型一致性。为验证所提方法的有效性,与Marchenko-Pastur主成分分析(MP-PCA)和基于全局指导下的局部高阶奇异值分解(GL-HOSVD)这两种扩散加权图像去噪算法进行实验对比。结果从DW图像、扩散张量场以及DTI量化参数的定量分析结果以及视觉效果来看,所提方法均优于MP-PCA与GL-HOSVD。结论本文所提方法能够从1幅非扩散加权图像和6幅DW图像得到准确的DTI量化参数,可减少临床采集时间,提高临床量化诊断的可靠性。 展开更多
关键词 扩散张量成像 张量场估计 3D u-net Rician噪声 图像去噪
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基于U-net3+的宫颈癌后装治疗中靶区和危及器官位置的预测
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作者 李霞 杨磊 +1 位作者 杨日赠 吴德华 《分子影像学杂志》 2023年第3期448-452,共5页
目的构建基于深度学习方法的宫颈癌后装治疗中高危靶区和危及器官位置预测方法。方法构建基于U-net3+的端到端自动分割框架,对两个中心213例已进行后装高剂量率治疗的宫颈癌患者进行勾画,并按照7:2:1的比例分为训练集、验证集和测试集... 目的构建基于深度学习方法的宫颈癌后装治疗中高危靶区和危及器官位置预测方法。方法构建基于U-net3+的端到端自动分割框架,对两个中心213例已进行后装高剂量率治疗的宫颈癌患者进行勾画,并按照7:2:1的比例分为训练集、验证集和测试集。勾画的内容包括高危临床靶区、膀胱、直肠和小肠,分别用豪斯多夫距离及戴斯相似系数评估预测模型的准确性。结果膀胱自动勾画的戴斯相似系数为0.953,直肠、小肠分别为0.885、0.857,危及器官的平均值是0.898,豪斯多夫距离平均为5.4 mm;高危临床靶区戴斯相似系数是0.869,豪斯多夫距离为8.1 mm。结论基于U-net3+的宫颈癌后装治疗中靶区和危及器官位置预测模型具有较高的准确率,同时训练耗费时间少,有望在临床进行应用推广。 展开更多
关键词 宫颈癌 后装治疗 位置预测 深度学习 u-net3+
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3D打印实物模型在颈椎疾患住院医师规范化培训教学中的应用和探讨
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作者 王玉强 许建中 +6 位作者 谭洪宇 鲍恒 李宇 刘会范 王秀玲 马陶然 花卉 《中国毕业后医学教育》 2024年第5期369-372,共4页
目的探讨3 D打印实物模型在提高颈椎疾患住院医师规范化培训(简称住培)教学效果中的作用。方法选取参加骨科住培的颈椎疾患学习的住院医师80名为研究对象,随机分为两组,观察组(40人)以幻灯讲解加3 D打印实物模型教学,对照组(40人)采用... 目的探讨3 D打印实物模型在提高颈椎疾患住院医师规范化培训(简称住培)教学效果中的作用。方法选取参加骨科住培的颈椎疾患学习的住院医师80名为研究对象,随机分为两组,观察组(40人)以幻灯讲解加3 D打印实物模型教学,对照组(40人)采用幻灯讲解教学。课后即时和课后1月分别对住院医师的知识掌握情况和诊疗技术进行现场测试,利用问卷的形式对住院医师的满意度和参与兴趣(10分法)进行调查。结果课后即时观察组的知识掌握情况和对照组相当(P>0.05),但是观察组的诊疗技术测试成绩显著高于对照组(P<0.05),观察组的满意度和参与兴趣评分均显著高于对照组,两者对比差异有统计学意义(均P<0.05);课后1月时,观察组的知识掌握情况和诊疗技术测试成绩均显著高于对照组(均P<0.05)。结论3 D打印实物模型应用于颈椎疾患住培的带教中,可显著提高教学效果,提升住院医师的满意度和参与兴趣,值得在住培教学中推广。 展开更多
关键词 3D打印 实物模型 颈椎 教学 住院医师规范化培训
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Defending Adversarial Examples by a Clipped Residual U-Net Model
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作者 Kazim Ali Adnan N.Qureshi +2 位作者 Muhammad Shahid Bhatti Abid Sohail Mohammad Hijji 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2237-2256,共20页
Deep learning-based systems have succeeded in many computer vision tasks.However,it is found that the latest study indicates that these systems are in danger in the presence of adversarial attacks.These attacks can qu... Deep learning-based systems have succeeded in many computer vision tasks.However,it is found that the latest study indicates that these systems are in danger in the presence of adversarial attacks.These attacks can quickly spoil deep learning models,e.g.,different convolutional neural networks(CNNs),used in various computer vision tasks from image classification to object detection.The adversarial examples are carefully designed by injecting a slight perturbation into the clean images.The proposed CRU-Net defense model is inspired by state-of-the-art defense mechanisms such as MagNet defense,Generative Adversarial Net-work Defense,Deep Regret Analytic Generative Adversarial Networks Defense,Deep Denoising Sparse Autoencoder Defense,and Condtional Generattive Adversarial Network Defense.We have experimentally proved that our approach is better than previous defensive techniques.Our proposed CRU-Net model maps the adversarial image examples into clean images by eliminating the adversarial perturbation.The proposed defensive approach is based on residual and U-Net learning.Many experiments are done on the datasets MNIST and CIFAR10 to prove that our proposed CRU-Net defense model prevents adversarial example attacks in WhiteBox and BlackBox settings and improves the robustness of the deep learning algorithms especially in the computer visionfield.We have also reported similarity(SSIM and PSNR)between the original and restored clean image examples by the proposed CRU-Net defense model. 展开更多
关键词 Adversarial examples adversarial attacks defense method residual learning u-net cgan cru-et model
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基于改进3D U-Net的多模态脑肿瘤分割算法
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作者 张丁轲 杨文霞 张园洲 《现代信息科技》 2023年第13期80-83,87,共5页
针对脑部肿瘤分割任务中存在的多模态信息利用率不高,训练样本数据少导致分割结构精度不高的问题,提出了一种以3D U-Net模型为基础,融合变分自编码器(VAE)和注意力模型的分割模型VAE U-Net,实现多模态脑肿瘤MRI图像的自动分割。所提方法... 针对脑部肿瘤分割任务中存在的多模态信息利用率不高,训练样本数据少导致分割结构精度不高的问题,提出了一种以3D U-Net模型为基础,融合变分自编码器(VAE)和注意力模型的分割模型VAE U-Net,实现多模态脑肿瘤MRI图像的自动分割。所提方法在Brats2020数据集上进行实验,在测试集上的整体肿瘤、核心肿瘤以及增强核心区的分割Dice系数分别为81.44、90.82和89.43,相较于原始的3DU-Net提高了2.03、1.05和2.38个百分点。 展开更多
关键词 脑肿瘤分割 深度学习 3D u-net 变分自编码器
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Integration of Sequence Stratigraphic Analysis and 3D Geostatistical Modeling of Pliocene–Pleistocene Delta,F3 Block,Netherlands
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作者 Haris Ahmed KHAN Ali Asghar SHAHID +3 位作者 Muhammad Jahangir KHAN Taher ZOUAGHI Maria Dolores ALVAREZ Syed Danial Mehdi NAQVI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期256-268,共13页
This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this resear... This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this research.The conventional techniques of 3D seismic interpretation were utilized to mark the 11 surfaces on the seismic section.Integration of seismic sequence stratigraphic interpretation,using well logs,and subsequent 3D geostatistical modeling,using seismic data,aided to evaluate the shallow hydrocarbon traps.The resulting models were obtained using System Tract and Facies models,which were generated by using sequential stimulation method and their variograms made by spherical method,moreover,these models are validated via histograms.The CDF curve generated from upscaling of well logs using geometric method,shows a good relation with less percentage of errors(1 to 2 for Facies and 3 to 4 for System Tract models)between upscaled and raw data that complements the resulted models.These approaches help us to delineate the best possible reservoir,lateral extent of system tracts(LST and/or HST)in the respective surface,and distribution of sand and shale in the delta.The clinoform break points alteration observed on seismic sections,also validates the sequence stratigraphic interpretation.The GR log-based Facies model and sequence stratigraphy-based System Tract model of SU-04-2 showed the reservoir characteristics,presence of sand bodies and majorly LST,respectively,mainly adjacent to the main fault of the studied area.Moreover,on the seismic section,SU-04-2 exhibits the presence of gas pockets at the same location that also complements the generated Facies and System Tract models.The generated models can be utilized for any similar kind of study and for the further research in the F3 block reservoir characterization. 展开更多
关键词 sequence stratigraphy facies modeling system tract modeling F3 block North Sea
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