期刊文献+
共找到517篇文章
< 1 2 26 >
每页显示 20 50 100
Combining machine learning algorithms with traditional methods for resolving the atomic-scale dynamic structure of monolayer MoS_(2) in high-resolution transmission electron microscopy 被引量:1
1
作者 Yu Meng Shuya Wang +5 位作者 Xibiao Ren Han Xue Xuejun Yue Chuanhong Jin Shanggang Lin Fang Lin 《Chinese Physics B》 2025年第1期162-170,共9页
High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-co... High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-corrected transmission electron microscopy constrain resolution.A machine learning algorithm is developed to determine the aberration parameters with higher precision from small,lattice-periodic crystal images.The proposed algorithm is then validated with simulated HRTEM images of graphene and applied to the experimental images of a molybdenum disulfide(MoS_(2))monolayer with 25 variables(14 aberrations)resolved in wide ranges.Using these measured parameters,the phases of the exit-wave functions are reconstructed for each image in a focal series of MoS_(2)monolayers.The images were acquired due to the unexpected movement of the specimen holder.Four-dimensional data extraction reveals time-varying atomic structures and ripple.In particular,the atomic evolution of the sulfur-vacancy point and line defects,as well as the edge structure near the amorphous,is visualized as the resolution has been improved from about 1.75?to 0.9 A.This method can help salvage important transmission electron microscope images and is beneficial for the images obtained from electron microscopes with average stability. 展开更多
关键词 aberration measurement high-resolution transmission electron microscopy feature-extraction networks exit-wave reconstruction monolayer MoS_(2)
原文传递
HRAM-VITON: High-Resolution Virtual Try-On with Attention Mechanism
2
作者 Yue Chen Xiaoman Liang +2 位作者 Mugang Lin Fachao Zhang Huihuang Zhao 《Computers, Materials & Continua》 2025年第2期2753-2768,共16页
The objective of image-based virtual try-on is to seamlessly integrate clothing onto a target image, generating a realistic representation of the character in the specified attire. However, existing virtual try-on met... The objective of image-based virtual try-on is to seamlessly integrate clothing onto a target image, generating a realistic representation of the character in the specified attire. However, existing virtual try-on methods frequently encounter challenges, including misalignment between the body and clothing, noticeable artifacts, and the loss of intricate garment details. To overcome these challenges, we introduce a two-stage high-resolution virtual try-on framework that integrates an attention mechanism, comprising a garment warping stage and an image generation stage. During the garment warping stage, we incorporate a channel attention mechanism to effectively retain the critical features of the garment, addressing challenges such as the loss of patterns, colors, and other essential details commonly observed in virtual try-on images produced by existing methods. During the image generation stage, with the aim of maximizing the utilization of the information proffered by the input image, the input features undergo double sampling within the normalization procedure, thereby enhancing the detail fidelity and clothing alignment efficacy of the output image. Experimental evaluations conducted on high-resolution datasets validate the effectiveness of the proposed method. Results demonstrate significant improvements in preserving garment details, reducing artifacts, and achieving superior alignment between the clothing and body compared to baseline methods, establishing its advantage in generating realistic and high-quality virtual try-on images. 展开更多
关键词 Virtual try-on attention mechanism high-resolution image generation
在线阅读 下载PDF
Fourier neural operator for high-resolution fluid flow simulation based on low-resolution data:the vorticity equation as an example
3
作者 Hongchao Qu Xiongbo Zheng +1 位作者 Lihong Yang Zhenya Song 《Acta Oceanologica Sinica》 2025年第6期165-177,共13页
In oceanic and atmospheric science,finer resolutions have become a prevailing trend in all aspects of development.For high-resolution fluid flow simulations,the computational costs of widely used numerical models incr... In oceanic and atmospheric science,finer resolutions have become a prevailing trend in all aspects of development.For high-resolution fluid flow simulations,the computational costs of widely used numerical models increase significantly with the resolution.Artificial intelligence methods have attracted increasing attention because of their high precision and fast computing speeds compared with traditional numerical model methods.The resolution-independent Fourier neural operator(FNO)presents a promising solution to the still challenging problem of high-resolution fluid flow simulations based on low-resolution data.Accordingly,we assess the potential of FNO for high-resolution fluid flow simulations using the vorticity equation as an example.We assess and compare the performance of FNO in multiple high-resolution tests varying the amounts of data and the evolution durations.When assessed with finer resolution data(even up to number of grid points with 1280×1280),the FNO model,trained at low resolution(number of grid points with 64×64)and with limited data,exhibits a stable overall error and good accuracy.Additionally,our work demonstrates that the FNO model takes less time than the traditional numerical method for high-resolution simulations.This suggests that FNO has the prospect of becoming a cost-effective and highly precise model for high-resolution simulations in the future.Moreover,FNO can make longer high-resolution predictions while training with less data by superimposing vorticity fields from previous time steps as input.A suitable initial learning rate can be set according to the frequency principle,and the time intervals of the dataset need to be adjusted according to the spatial resolution of the input when training the FNO model.Our findings can help optimize FNO for future fluid flow simulations. 展开更多
关键词 Fourier neural operator high-resolution simulation fluid flow vorticity equation
暂未订购
Comparative analysis of different machine learning algorithms for urban footprint extraction in diverse urban contexts using high-resolution remote sensing imagery
4
作者 GUI Baoling Anshuman BHARDWAJ Lydia SAM 《Journal of Geographical Sciences》 2025年第3期664-696,共33页
While algorithms have been created for land usage in urban settings,there have been few investigations into the extraction of urban footprint(UF).To address this research gap,the study employs several widely used imag... While algorithms have been created for land usage in urban settings,there have been few investigations into the extraction of urban footprint(UF).To address this research gap,the study employs several widely used image classification method classified into three categories to evaluate their segmentation capabilities for extracting UF across eight cities.The results indicate that pixel-based methods only excel in clear urban environments,and their overall accuracy is not consistently high.RF and SVM perform well but lack stability in object-based UF extraction,influenced by feature selection and classifier performance.Deep learning enhances feature extraction but requires powerful computing and faces challenges with complex urban layouts.SAM excels in medium-sized urban areas but falters in intricate layouts.Integrating traditional and deep learning methods optimizes UF extraction,balancing accuracy and processing efficiency.Future research should focus on adapting algorithms for diverse urban landscapes to enhance UF extraction accuracy and applicability. 展开更多
关键词 urban footprint mapping high-resolution remote sensing imagery machine learning deep learning segmentanythingmodel
原文传递
High-resolution Standardized Precipitation Evapotranspiration Index(SPEI)reveals trends in drought and vegetation water availability in China
5
作者 Qian He Ming Wang +1 位作者 Kai Liu Bowen Wang 《Geography and Sustainability》 2025年第2期117-130,共14页
Understanding vegetation water availability can be important for managing vegetation and combating climate change.Changes in vegetation water availability throughout China remains poorly understood,especially at a hig... Understanding vegetation water availability can be important for managing vegetation and combating climate change.Changes in vegetation water availability throughout China remains poorly understood,especially at a high spatial resolution.Standardized Precipitation Evapotranspiration Index(SPEI)is an ideal water availability index for assessing the spatiotemporal characteristics of drought and investigating the vegetation-water availability relationship.However,no high-resolution and long-term SPEI datasets over China are available.To fill this gap,we developed a new model based on machine learning to obtain high-resolution(1 km)SPEI data by combining climate variables with topographical and geographical features.Here,we analyzed the long-term drought over the past century(1901–2020)and vegetation-water availability relationship in the past two decades(2000–2020).The century-long drought trend analyses indicated an overall drying trend across China with increasing drought frequency,duration,and severity during the past century.We found that drought events in 1901–1961 showed a larger increase than that in 1961–2020,with the Qinghai-Xizang Plateau showing a significant drying trend during 1901–1960 but a wetting trend during 1961–2020.There were 13.90%and 28.21%of vegetation in China showing water deficit and water surplus respectively during 2000–2020.The water deficit area significantly shrank from 2000 to 2020 across China,which is dominated by the significant decrease in water deficit areas in South China.Among temperature,precipitation,and vegetation abundance,temperature is the most important factor for the vegetation-water availability dynamics in China over the past two decades,with high temperature contributing to water deficit.Our findings are important for water and vegetation management under a warming climate. 展开更多
关键词 Standardized Precipitation Evapotranspiration Index(SPEI) Long-term drought Vegetation-water relationship high-resolution dataset
在线阅读 下载PDF
Integrating high-resolution mass spectrometry and transcriptomics to explore the therapeutic mechanism of Sanhuang Oil in diabetic foot
6
作者 Ping Sun Yu-Feng Zhang +4 位作者 Shuang Li Wei Zhang Peng-Fei Zhao Chen-Xia Li Chen-Ning Zhang 《Traditional Medicine Research》 2026年第1期19-38,共20页
Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-... Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-inflammatory,and immunomodulatory activities.However,its active constituents and mechanisms of action against diabetic foot remain to be elucidated.Methods:In this study,the chemical constituents of Sanhuang Oil were identified using UPLC-QE-Orbitrap-MS.Subsequently,the mechanism by which Sanhuang Oil promotes diabetic foot ulcer healing was predicted by integrating network pharmacology and molecular docking.Additionally,diabetic mouse model was established in ICR mice using a combination of a high-fat diet(HFD)and streptozotocin(STZ)chemical induction.A full-thickness skin defect was created on the dorsum of the mice.Wound healing and the healing rate were observed following Sanhuang Oil intervention.The mechanism underlying Sanhuang Oil’s promotion of diabetic ulcer healing was further investigated using transcriptomics and histopathological examination(H&E staining).Results:A total of 97 active ingredients were identified from Sanhuang Oil.Network pharmacology analysis predicted 543 common targets,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis identified 203 relevant pathways.Molecular docking further confirmed high binding affinity(binding energy≤−5.0 kcal/mol)between specific active components in Sanhuang Oil(e.g.,coptisine,phellodendrine,baicalein)and key targets associated with diabetic foot ulcers(e.g.,EGFR,AKT1,STAT3).In vivo experimental results demonstrated that the wound healing rate was significantly higher in Sanhuang Oil-treated groups compared to the model group(P<0.001).HE staining revealed that the high-dose Sanhuang Oil group exhibited more pronounced epithelial tissue coverage over the wound,reduced inflammatory cell infiltration,and increased collagen deposition and fibroblast proliferation.transcriptomic analysis identified Pdk4,Ttn,Csrp3,Actn2,Myoz2,Tnnc2,Myod1,Myog,Myot,and Myf6 as key regulatory proteins involved in promoting wound healing.Conclusion:Sanhuang Oil promotes wound healing in diabetic ulcer mice,potentially by mitigating inflammation and regulating key targets such as Pdk4 to enhance fibroblast function.These findings provide novel insights into the multi-target,multi-pathway mechanism of Sanhuang Oil for treating diabetic foot ulcers. 展开更多
关键词 Sanhuang Oil diabetic foot high-resolution mass spectrometry molecular network analysis mechanism of action
暂未订购
Multi-scale intelligent fusion and dynamic validation for high-resolution seismic data processing in drilling
7
作者 YUAN Sanyi XU Yanwu +2 位作者 XIE Renjun CHEN Shuai YUAN Junliang 《Petroleum Exploration and Development》 2025年第3期680-691,共12页
During drilling operations,the low resolution of seismic data often limits the accurate characterization of small-scale geological bodies near the borehole and ahead of the drill bit.This study investigates high-resol... During drilling operations,the low resolution of seismic data often limits the accurate characterization of small-scale geological bodies near the borehole and ahead of the drill bit.This study investigates high-resolution seismic data processing technologies and methods tailored for drilling scenarios.The high-resolution processing of seismic data is divided into three stages:pre-drilling processing,post-drilling correction,and while-drilling updating.By integrating seismic data from different stages,spatial ranges,and frequencies,together with information from drilled wells and while-drilling data,and applying artificial intelligence modeling techniques,a progressive high-resolution processing technology of seismic data based on multi-source information fusion is developed,which performs simple and efficient seismic information updates during drilling.Case studies show that,with the gradual integration of multi-source information,the resolution and accuracy of seismic data are significantly improved,and thin-bed weak reflections are more clearly imaged.The updated seismic information while-drilling demonstrates high value in predicting geological bodies ahead of the drill bit.Validation using logging,mud logging,and drilling engineering data ensures the fidelity of the processing results of high-resolution seismic data.This provides clearer and more accurate stratigraphic information for drilling operations,enhancing both drilling safety and efficiency. 展开更多
关键词 high-resolution seismic data processing while-drilling update while-drilling logging multi-source information fusion thin-bed weak reflection artificial intelligence modeling
在线阅读 下载PDF
基于多分支HRNet的图像篡改检测与定位模型 被引量:1
8
作者 曾桢 谭平 《现代电子技术》 北大核心 2025年第3期35-42,共8页
传统的篡改方法如拷贝粘贴和拼接已演变为利用深度学习生成的高质量伪造图像,这些篡改技术在图像纹理和细节上留下难以察觉的痕迹,如高频噪声模式的异常、颜色分布的微妙变化,以及边缘区域的不自然过渡。这些痕迹分布在不同分辨率层次... 传统的篡改方法如拷贝粘贴和拼接已演变为利用深度学习生成的高质量伪造图像,这些篡改技术在图像纹理和细节上留下难以察觉的痕迹,如高频噪声模式的异常、颜色分布的微妙变化,以及边缘区域的不自然过渡。这些痕迹分布在不同分辨率层次和空间位置,增加了检测的难度。现有模型在整合多尺度和多位置特征时存在不足,难以有效捕捉局部细微纹理变化。针对这一问题,文中提出一种基于多分支HRNet的图像篡改检测与定位模型。该模型通过集成纹理增强模块,增强对图像篡改细节特征的捕获能力。同时,结合Spatial Weighting与Cross Resolution Weighting策略优化特征融合,并使用新的损失函数W_Arcloss,显著提升了模型在复杂篡改检测任务中的性能。在CASIA、Columbia、COVERAGE和NIST16等数据集上,该模型的检测准确度相较于PSCC⁃Net、HIFI⁃Net模型分别平均提升了6.5%与0.8%,并且泛化能力得到提升。这些结果证明了模型在处理多种篡改类型时的有效性和鲁棒性,为图像篡改检测与定位领域提供了新的研究视角和技术手段。 展开更多
关键词 图像篡改检测 深度学习 多分支hrnet 纹理增强模块 Spatial Weighting Cross Resolution Weighting W_Arcloss
在线阅读 下载PDF
Investigating the relationship between intracranial atherosclerotic plaque remodelling and diabetes using high-resolution vessel wall imaging 被引量:3
9
作者 Yong-Qian Mo Hai-Yu Luo +5 位作者 Han-Wen Zhang Yu-Feng Liu Kan Deng Xiao-Lei Liu Biao Huang Fan Lin 《World Journal of Diabetes》 SCIE 2024年第1期72-80,共9页
BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imag... BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imaging(HR-VWI).AIM To investigate the factors of intracranial atherosclerotic remodelling patterns and the relationship between intracranial atherosclerotic remodelling and diabetes mellitus using HR-VWI.METHODS Ninety-four patients diagnosed with middle cerebral artery or basilar artery INTRODUCTION Intracranial atherosclerotic disease is one of the main causes of ischaemic stroke in the world,accounting for approx-imately 10%of transient ischaemic attacks and 30%-50%of ischaemic strokes[1].It is the most common factor among Asian people[2].The adaptive changes in the structure and function of blood vessels that can adapt to changes in the internal and external environment are called vascular remodelling,which is a common and important pathological mechanism in atherosclerotic diseases,and the remodelling mode of atherosclerotic plaques is closely related to the occurrence of stroke.Positive remodelling(PR)is an outwards compensatory remodelling where the arterial wall grows outwards in an attempt to maintain a constant lumen diameter.For a long time,it was believed that the degree of stenosis can accurately reflect the risk of ischaemic stroke[3-5].Previous studies have revealed that lesions without significant luminal stenosis can also lead to acute events[6,7],as summarized in a recent meta-analysis study in which approximately 50%of acute/subacute ischaemic events were due to this type of lesion[6].Research[8,9]has pointed out that the PR of plaques is more dangerous and more likely to cause acute ischaemic stroke.Previous studies[10-13]have found that there are specific vascular remodelling phenomena in the coronary and carotid arteries of diabetic patients.However,due to the deep location and small lumen of intracranial arteries and limitations of imaging techniques,the relationship between intracranial arterial remodelling and diabetes is still unclear.In recent years,with the development of magnetic resonance technology and the emergence of high-resolution(HR)vascular wall imaging,a clear and multidimensional display of the intracranial vascular wall has been achieved.Therefore,in this study,HR wall imaging(HR-VWI)was used to display the remodelling characteristics of bilateral middle cerebral arteries and basilar arteries and to explore the factors of intracranial vascular remodelling and its relationship with diabetes. 展开更多
关键词 high-resolution vessel wall imaging Intracranial atherosclerosis Vascular remodelling Magnetic resonance imaging
暂未订购
High-resolution magnetic resonance imaging in the diagnosis and management of vertebral artery dissection:A case report 被引量:1
10
作者 Hai-Bin Zhang Yong-Hong Duan +1 位作者 Min Zhou Ri-Chu Liang 《World Journal of Radiology》 2024年第10期593-599,共7页
BACKGROUND Vertebral artery dissection(VAD)is a rare but life-threatening condition characterized by tearing of the intimal layer of the vertebral artery,leading to stenosis,occlusion or rupture.The clinical presentat... BACKGROUND Vertebral artery dissection(VAD)is a rare but life-threatening condition characterized by tearing of the intimal layer of the vertebral artery,leading to stenosis,occlusion or rupture.The clinical presentation of VAD can be heterogeneous,with common symptoms including headache,dizziness and balance problems.Timely diagnosis and treatment are crucial for favorable outcomes;however,VAD is often missed due to its variable clinical presentation and lack of robust diagnostic guidelines.High-resolution magnetic resonance imaging(HRMRI)has emerged as a reliable diagnostic tool for VAD,providing detailed visualization of vessel wall abnormalities.CASE SUMMARY A young male patient presented with an acute onset of severe headache,vomiting,and seizures,followed by altered consciousness.Imaging studies revealed bilateral VAD,basilar artery thrombosis,multiple brainstem and cerebellar infarcts,and subarachnoid hemorrhage.Digital subtraction angiography(DSA)revealed vertebral artery stenosis but failed to detect the dissection,potentially because intramural thrombosis obscured the VAD.In contrast,HRMRI confirmed the diagnosis by revealing specific signs of dissection.The patient was managed conservatively with antiplatelet therapy and other supportive measures,such as blood pressure control and pain management.After 5 mo of rehabilitation,the patient showed significant improvement in swallowing and limb strength.CONCLUSION HR-MRI can provide precise evidence for the identification of VAD. 展开更多
关键词 Vertebral artery dissection Subarachnoid hemorrhage Brainstem infarction DIAGNOSIS high-resolution magnetic resonance imaging Case report
暂未订购
Individual tree detection and counting based on high-resolution imagery and the canopy height model data 被引量:1
11
作者 Ye Zhang Moyang Wang +3 位作者 Joseph Mango Liang Xin Chen Meng Xiang Li 《Geo-Spatial Information Science》 CSCD 2024年第6期2162-2178,共17页
Individual Tree Detection-and-Counting(ITDC)is among the important tasks in town areas,and numerous methods are proposed in this direction.Despite their many advantages,still,the proposed methods are inadequate to pro... Individual Tree Detection-and-Counting(ITDC)is among the important tasks in town areas,and numerous methods are proposed in this direction.Despite their many advantages,still,the proposed methods are inadequate to provide robust results because they mostly rely on the direct field investigations.This paper presents a novel approach involving high-resolution imagery and the Canopy-Height-Model(CHM)data to solve the ITDC problem.The new approach is studied in six urban scenes:farmland,woodland,park,industrial land,road and residential areas.First,it identifies tree canopy regions using a deep learning network from high-resolution imagery.It then deploys the CHM-data to detect treetops of the canopy regions using a local maximum algorithm and individual tree canopies using the region growing.Finally,it calculates and describes the number of individual trees and tree canopies.The proposed approach is experimented with the data from Shanghai,China.Our results show that the individual tree detection method had an average overall accuracy of 0.953,with a precision of 0.987 for woodland scene.Meanwhile,the R^(2) value for canopy segmentation in different urban scenes is greater than 0.780 and 0.779 for canopy area and diameter size,respectively.These results confirm that the proposed method is robust enough for urban tree planning and management. 展开更多
关键词 Individual tree detection-and-counting(ITDC) deep learning high-resolution imagery Canopy Height Model data(CHM)
原文传递
基于改进HRNet和椭圆拟合的PDC钻头复合片磨损定级方法
12
作者 程占波 熊凌 +3 位作者 丁昕 陈刚 叶道辉 李姝凡 《石油机械》 北大核心 2025年第8期25-34,43,共11页
针对目前PDC钻头复合片磨损定级存在效率低、标准性差、精度不足等问题,提出一种基于改进HRNet和椭圆拟合的磨损定级方法。使用语义分割算法对复合片轮廓进行提取,使用深度可分离卷积替换HRNet网络的普通卷积,对网络特征提取层的4个不... 针对目前PDC钻头复合片磨损定级存在效率低、标准性差、精度不足等问题,提出一种基于改进HRNet和椭圆拟合的磨损定级方法。使用语义分割算法对复合片轮廓进行提取,使用深度可分离卷积替换HRNet网络的普通卷积,对网络特征提取层的4个不同分辨率输出通过CGAF模块进行特征融合,同时对融合特征图引入EMA注意力模块。通过RANSAC椭圆拟合算法进行数据预处理、拟合椭圆筛选及内点补充,进而提高分割复合片的拟合精度。并对复合片进行磨损定级。试验结果表明:改进后的HRNet网络平均交并比、类别平均像素准确率与原HRNet网络相比达到97.60%和98.79%,参数量降低72%,模型大小减小70%,定级准确率达到96.5%,单张复合片定级所需平均时间仅为0.261 s。所得结论可为油田降低钻井成本提供理论参考。 展开更多
关键词 PDC钻头复合片 磨损定级 hrnet网络模型 椭圆拟合 CGAF模块 语义分割
在线阅读 下载PDF
融合HRNet模块和可变形注意力机制的乳腺癌图像分类技术研究
13
作者 田兄玲 宋丽俊 +1 位作者 郭辉 王贝 《机器人外科学杂志(中英文)》 2025年第9期1454-1460,共7页
目的:通过融合高分辨率网络(HRNet)模块和动态可变形注意力机制改进U-Net模型实现对乳腺癌图像的高精度分类与诊断。方法:研究提出的模型以U-Net为基础,引入了高分辨率网络强大、空洞空间金字塔池化模块以捕获多尺度信息,并融合了全局... 目的:通过融合高分辨率网络(HRNet)模块和动态可变形注意力机制改进U-Net模型实现对乳腺癌图像的高精度分类与诊断。方法:研究提出的模型以U-Net为基础,引入了高分辨率网络强大、空洞空间金字塔池化模块以捕获多尺度信息,并融合了全局多尺度注意力机制、多尺度残差卷积模块和动态可变形注意力机制,从而提升模型对关键特征的关注能力。结果:改进U-Net-HRNet模型在分类准确率、召回率、精确率、F1-measure、Jaccard指数和Dice相似度系数等关键性能指标上均优于现有的乳腺癌图像分类方法。此外,消融实验结果显示,在去除各模块后,模型的性能显著降低,其中高分辨率网络模块对模型性能的影响最为显著。在去除高分辨率网络模块后,模型的准确率、F1-measure、Jaccard指数及Dice相似度系数分别降低了6.9%、7.8%、11.7%和14.1%。结论:改进U-Net-HRNet模型在乳腺癌图像分类任务中具备显著的优越性,能为乳腺癌的临床诊断提供有效辅助。 展开更多
关键词 乳腺癌 图像分类 hrnet 空洞空间金字塔池化 动态可变形注意力
在线阅读 下载PDF
Verification and Validation of High-Resolution Inviscid and Viscous Conical Nozzle Flows
14
作者 Luciano K.Araki Rafael B.de R.Borges +1 位作者 Nicholas Dicati P.da Silva Chi-Wang Shu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期533-549,共17页
Capturing elaborated flow structures and phenomena is required for well-solved numerical flows.The finite difference methods allow simple discretization of mesh and model equations.However,they need simpler meshes,e.g... Capturing elaborated flow structures and phenomena is required for well-solved numerical flows.The finite difference methods allow simple discretization of mesh and model equations.However,they need simpler meshes,e.g.,rectangular.The inverse Lax-Wendroff(ILW)procedure can handle complex geometries for rectangular meshes.High-resolution and high-order methods can capture elaborated flow structures and phenomena.They also have strong mathematical and physical backgrounds,such as positivity-preserving,jump conditions,and wave propagation concepts.We perceive an effort toward direct numerical simulation,for instance,regarding weighted essentially non-oscillatory(WENO)schemes.Thus,we propose to solve a challenging engineering application without turbulence models.We aim to verify and validate recent high-resolution and high-order methods.To check the solver accuracy,we solved vortex and Couette flows.Then,we solved inviscid and viscous nozzle flows for a conical profile.We employed the finite difference method,positivity-preserving Lax-Friedrichs splitting,high-resolution viscous terms discretization,fifth-order multi-resolution WENO,ILW,and third-order strong stability preserving Runge-Kutta.We showed the solver is high-order and captured elaborated flow structures and phenomena.One can see oblique shocks in both nozzle flows.In the viscous flow,we also captured a free-shock separation,recirculation,entrainment region,Mach disk,and the diamond-shaped pattern of nozzle flows. 展开更多
关键词 high-resolution COMPRESSIBLE NAVIER-STOKES Free-shock separation Nozzle flow
在线阅读 下载PDF
High-resolution multi-scale air pollution system:Evaluation of modelling performance and emission control strategies
15
作者 Diogo Lopes Joana Ferreira +6 位作者 Sandra Rafael Ka In Hoi Xin Li Yuan Liu Ka-Veng Yuen Kai Meng Mok Ana Isabel Miranda 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第3期65-81,共17页
A high percentage of the world's population lives in areas where air pollutant concentrations exceed the World Health Organization guidelines.This work aims to develop and test,a high-resolution multi-scale air po... A high percentage of the world's population lives in areas where air pollutant concentrations exceed the World Health Organization guidelines.This work aims to develop and test,a high-resolution multi-scale air pollution modelling system by integrating a set of adequate tools.This system is able to provide detailed air pollutant concentrations in urban areas and support air quality management strategies through a better identification of different atmospheric processes.It also allows furthering the design and assessment of air pollution control measures for a specific area.To evaluate its performance and suitability,the system was applied to the Macao Special Administrative Region(SAR),China,one of the most densely populated areas on earth,during a winter period when this area is affected by high levels of Particulate Matter(PM).Although the developed system tends to underestimate the PM concentrations,it revealed a good performance in reproducing the temporal and spatial air pollution patterns.Several exceedances of the Chinese air quality standards were calculated and high population exposure to PM pollution was estimated.The tested urban atmospheric emission reduction scenarios have shown air quality improvements,indicating that emission reduction measures at urban level should focus on the domestic sector.However,it is crucial to implement joint pollution prevention strategies with neighbouring regions to improve the air quality in Macao SAR.The approach developed in this work can support policymakers in defining new strategies to reduce atmospheric pollution in urban areas. 展开更多
关键词 Urban areas high-resolution emission inventory Particulate matter Population exposure
原文传递
A High-Resolution Measurement Method for Inner and Outer 3D Surface Profiles of Laser Fusion Targets Using a Laser Differential Confocal–Atomic Force Probe Technique
16
作者 Weiqian Zhao Zihao Liu Lirong Qiu 《Engineering》 SCIE EI CAS CSCD 2024年第10期51-60,共10页
The high-resolution and nondestructive co-reference measurement of the inner and outer threedimensional(3D)surface profiles of laser fusion targets is difficult to achieve.In this study,we propose a laser differential... The high-resolution and nondestructive co-reference measurement of the inner and outer threedimensional(3D)surface profiles of laser fusion targets is difficult to achieve.In this study,we propose a laser differential confocal(LDC)–atomic force probe(AFP)method to measure the inner and outer 3D surface profiles of laser fusion targets at a high resolution.This method utilizes the LDC method to detect the deflection of the AFP and exploits the high spatial resolution of the AFP to enhance the spatial resolution of the outer profile measurement.Nondestructive and co-reference measurements of the inner profile of a target were achieved using the tomographic characteristics of the LDC method.Furthermore,by combining multiple repositionings of the target using a horizontal slewing shaft,the inner and outer 3D surface profiles of the target were obtained,along with a power spectrum assessment of the entire surface.The experimental results revealed that the respective axial and lateral resolutions of the outer profile measurement were 0.5 and 1.3 nm,while the respective axial and lateral resolutions of the inner profile measurement were 2.0 nm and approximately 400.0 nm.The repeatabilities of the rootmean-square deviation measurements for the outer and inner profiles of the target were 2.6 and 2.4 nm,respectively.We believe our study provides a promising method for the high-resolution and nondestructive co-reference measurement of the inner and outer 3D profiles of laser fusion targets. 展开更多
关键词 Laser fusion targets Laser differential confocal-atomic force probe high-resolution Nondestructive Co-reference
在线阅读 下载PDF
Accurate Source-Receiver Positioning Method for a High-Resolution Deep-Towed Multichannel Seismic Exploration System
17
作者 LI Jing LIU Kai +5 位作者 WEI Zhengrong ZHANG Liancheng LIU Yangting PEI Yanliang LIU Chenguang LIU Baohua 《Journal of Ocean University of China》 CAS CSCD 2024年第2期415-426,共12页
The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high... The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high vertical and horizontal resolution.However,the quality of deep-towed seismic imaging hinges on accurate source-receiver positioning information.In light of existing technical problems,we propose a novel array geometry inversion method tailored for high-resolution deep-towed multichannel seismic exploration systems.This method is independent of the attitude and depth sensors along a deep-towed seismic streamer,accounting for variations in seawater velocity and seabed slope angle.Our approach decomposes the towed line array into multiline segments and characterizes its geometric shape using the line segment distance and pitch angle.Introducing optimization parameters for seawater velocity and seabed slope angle,we establish an objective function based on the model,yielding results that align with objective reality.Employing the particle swarm optimization algorithm enables synchronous acquisition of optimized inversion results for array geometry and seawater velocity.Experimental validation using theoretical models and practical data verifies that our approach effectively enhances source and receiver positioning inversion accuracy.The algorithm exhibits robust stability and reliability,addressing uncertainties in seismic traveltime picking and complex seabed topography conditions. 展开更多
关键词 high-resolution deep-towed multichannel seismic exploration source-receiver positioning array geometry inversion seawater heterogeneity seabed slope angle
在线阅读 下载PDF
In vivo pilot study into superficial microcirculatory characteristics of colorectal adenomas using novel high-resolution magnifying endoscopy with blue laser imaging
18
作者 Hai-Bin Dong Tao Chen +2 位作者 Xiao-Fei Zhang Yu-Tang Ren Bo Jiang 《World Journal of Gastrointestinal Endoscopy》 2024年第4期206-213,共8页
BACKGROUND No studies have yet been conducted on changes in microcirculatory hemody-namics of colorectal adenomas in vivo under endoscopy.The microcirculation of the colorectal adenoma could be observed in vivo by a n... BACKGROUND No studies have yet been conducted on changes in microcirculatory hemody-namics of colorectal adenomas in vivo under endoscopy.The microcirculation of the colorectal adenoma could be observed in vivo by a novel high-resolution magnification endoscopy with blue laser imaging(BLI),thus providing a new insight into the microcirculation of early colon tumors.AIM To observe the superficial microcirculation of colorectal adenomas using the novel magnifying colonoscope with BLI and quantitatively analyzed the changes in hemodynamic parameters.METHODS From October 2019 to January 2020,11 patients were screened for colon adenomas with the novel high-resolution magnification endoscope with BLI.Video images were recorded and processed with Adobe Premiere,Adobe Photoshop and Image-pro Plus software.Four microcirculation parameters:Microcirculation vessel density(MVD),mean vessel width(MVW)with width standard deviation(WSD),and blood flow velocity(BFV),were calculated for adenomas and the surrounding normal mucosa.RESULTS A total of 16 adenomas were identified.Compared with the normal surrounding mucosa,the superficial vessel density in the adenomas was decreased(MVD:0.95±0.18 vs 1.17±0.28μm/μm2,P<0.05).MVW(5.11±1.19 vs 4.16±0.76μm,P<0.05)and WSD(11.94±3.44 vs 9.04±3.74,P<0.05)were both increased.BFV slowed in the adenomas(709.74±213.28 vs 1256.51±383.31μm/s,P<0.05).CONCLUSION The novel high-resolution magnification endoscope with BLI can be used for in vivo study of adenoma superficial microcirculation.Superficial vessel density was decreased,more irregular,with slower blood flow. 展开更多
关键词 ADENOMA MICROCIRCULATION high-resolution magnification endoscopy Blue laser imaging
暂未订购
基于改进HRNet和PPM的图像语义分割方法的研究
19
作者 师佳琪 杨皓浚 +1 位作者 刘晓悦 陈鑫 《现代电子技术》 北大核心 2025年第7期29-34,共6页
为解决现有语义分割模型无法兼顾全局语义信息与局部细节信息,以及残差模块细节特征提取能力弱的问题,提出一种语义分割方法。在HRNet的基础上引入了金字塔池化模块,兼顾了全局语义信息和局部细节信息,同时在原有残差模块Basic Block的... 为解决现有语义分割模型无法兼顾全局语义信息与局部细节信息,以及残差模块细节特征提取能力弱的问题,提出一种语义分割方法。在HRNet的基础上引入了金字塔池化模块,兼顾了全局语义信息和局部细节信息,同时在原有残差模块Basic Block的基础上引入大核深度卷积提高模型的细节特征提取能力,大幅度提高模型的精度。在PASCAL VOC2012图像数据集上的实验表明,相较于原始HRNet等其他分割网络,该算法取得了分割精度的显著提升,平均分割精度达到了89.27%。各设计模块的有效性也通过消融实验得以验证,尤其是改进Basic Block对提升分割性能具有关键作用,该模型大幅度提升了图像语义分割精度,提供了一种高效率、稳定且适用场景更加普遍的多尺度语义分割算法。 展开更多
关键词 hrnet 金字塔池化模块 大核深度卷积 残差模块 语义分割 深度学习
在线阅读 下载PDF
基于HRNet的手部穴位定位方法研究 被引量:1
20
作者 曹江山 朱树先 +1 位作者 禹宝庆 宁丁 《计算机仿真》 2025年第5期438-445,共8页
针对手部穴位关键点检测模型特征冗余、精度不足等问题,提出了一种改进的HRNet模型。在主干网络中引入了SRU和CRU模块串联的SCConv模块来取代传统卷积操作,以增强特征提取效果并减少特征冗余;同时引入特征解耦合模块以进一步减少特征冗... 针对手部穴位关键点检测模型特征冗余、精度不足等问题,提出了一种改进的HRNet模型。在主干网络中引入了SRU和CRU模块串联的SCConv模块来取代传统卷积操作,以增强特征提取效果并减少特征冗余;同时引入特征解耦合模块以进一步减少特征冗余,并增强特征;损失函数方面引入互信息损失函数与MSE Loss函数相加作为总的损失,以引导模型对有用特征进行更好的分辨,从而达到增强特征、减少冗余的目的。实验结果表明,在自建手部穴位数据集上,所提出的模型相较于HRNet模型分别提升了1.8%和2.5%的AP和PCK值,有效地提高了对穴位定位能力。 展开更多
关键词 关键点检测 深度学习 高分辨率网络 手部穴位
在线阅读 下载PDF
上一页 1 2 26 下一页 到第
使用帮助 返回顶部