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基于改进U-Net3+模型的无人机正射影像语义分割
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作者 姜磊 梁聪 +4 位作者 赵旭 王鹏 闫文凯 杨宏鼎 吴继忠 《测绘通报》 北大核心 2026年第2期137-143,共7页
为解决U-Net3+模型在无人机正射影像语义分割时特征抽象层次不足与跨尺度特征冗余的问题,本文提出了一种改进的U-Net3+模型。改进模型引入基于残差网络架构的深度卷积神经网络ResNet50作为特征提取主干网络,同时引入卷积注意力模块作为... 为解决U-Net3+模型在无人机正射影像语义分割时特征抽象层次不足与跨尺度特征冗余的问题,本文提出了一种改进的U-Net3+模型。改进模型引入基于残差网络架构的深度卷积神经网络ResNet50作为特征提取主干网络,同时引入卷积注意力模块作为轻量级注意力机制。试验结果表明:改进U-Net3+模型的总体准确率、平均交并比、F1分数比原始U-Net3+分别高出8.3%、2.6%和1.9%,且优于FCN、U-Net、U-Net++和DeepLab系列主流语义分割模型,改进U-Net3+模型在典型场景下表现出更强的特征区分能力和更高的准确性;仅引入ResNet50或CBAM无法达到最佳效果,ResNet50与CBAM的协同作用可显著增强模型在复杂场景下的识别能力。改进U-Net3+模型的分割精度有明显改善,为无人机正射影像语义分割提供了有效的技术解决方案。 展开更多
关键词 无人机正射影像 语义分割 u-net3+ ResNet50 卷积注意力模块
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An effective deep-learning prediction of Arctic sea-ice concentration based on the U-Net model
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作者 Yifan Xie Ke Fan +2 位作者 Hongqing Yang Yi Fan Shengping He 《Atmospheric and Oceanic Science Letters》 2026年第1期34-40,共7页
Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiote... Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiotemporal distribution of Arctic SIC is more challenging than predicting its total extent.In this study,spatiotemporal prediction models for monthly Arctic SIC at 1-to 3-month leads are developed based on U-Net-an effective convolutional deep-learning approach.Based on explicit Arctic sea-ice-atmosphere interactions,11 variables associated with Arctic sea-ice variations are selected as predictors,including observed Arctic SIC,atmospheric,oceanic,and heat flux variables at 1-to 3-month leads.The prediction skills for the monthly Arctic SIC of the test set(from January 2018 to December 2022)are evaluated by examining the mean absolute error(MAE)and binary accuracy(BA).Results showed that the U-Net model had lower MAE and higher BA for Arctic SIC compared to two dynamic climate prediction systems(CFSv2 and NorCPM).By analyzing the relative importance of each predictor,the prediction accuracy relies more on the SIC at the 1-month lead,but on the surface net solar radiation flux at 2-to 3-month leads.However,dynamic models show limited prediction skills for surface net solar radiation flux and other physical processes,especially in autumn.Therefore,the U-Net model can be used to capture the connections among these key physical processes associated with Arctic sea ice and thus offers a significant advantage in predicting Arctic SIC. 展开更多
关键词 Arctic sea-ice concentration Deep-learning prediction u-net model CFSv2 NorCPM
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Tea Leaf Disease Diagnosis Based on Improved Lightweight U-Net3+
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作者 HU Yumeng GUAN Feifan +5 位作者 XIE Dongchen MA Ping YU Youben ZHOU Jie NIE Yanming HUANG Lüwen 《智慧农业(中英文)》 2026年第1期15-27,共13页
[Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis... [Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis of the severity of tea spots was proposed in this research,designated as MDC-U-Net3+,to enhance segmentation accuracy on the base framework of U-Net3+.[Methods]Multi-scale feature fusion module(MSFFM)was incorporated into the backbone network of U-Net3+to obtain feature information across multiple receptive fields of diseased spots,thereby reducing the loss of features within the encoder.Dual multi-scale attention(DMSA)was incorporated into the skip connection process to mitigate the segmentation boundary ambiguity issue.This integration facilitates the comprehensive fusion of fine-grained and coarse-grained semantic information at full scale.Furthermore,the segmented mask image was subjected to conditional random fields(CRF)to enhance the optimization of the segmentation results[Results and Discussions]The improved model MDC-U-Net3+achieved a mean pixel accuracy(mPA)of 94.92%,accompanied by a mean Intersection over Union(mIoU)ratio of 90.9%.When compared to the mPA and mIoU of U-Net3+,MDC-U-Net3+model showed improvements of 1.85 and 2.12 percentage points,respectively.These results illustrated a more effective segmentation performance than that achieved by other classical semantic segmentation models.[Conclusions]The methodology presented herein could provide data support for automated disease detection and precise medication,consequently reducing the losses associated with tea diseases. 展开更多
关键词 disease diagnosis semantic segmentation u-net3+ multi-scale feature fusion attention mechanism conditional random fields
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结合U-Net优化和3D跟踪算法的光伏电站设备实时监测技术研究
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作者 杨志仁 《自动化应用》 2026年第3期187-190,共4页
光伏电站的可靠运作对电力供应的稳定性具有重大意义,然而,传统人工巡检方式存在效率低、时效性差等问题。为此,提出了一种创新的光伏电站设备实时监测模型,该模型通过利用扩张残差网络对U-Net进行优化,并融合三维跟踪算法,最终在电气... 光伏电站的可靠运作对电力供应的稳定性具有重大意义,然而,传统人工巡检方式存在效率低、时效性差等问题。为此,提出了一种创新的光伏电站设备实时监测模型,该模型通过利用扩张残差网络对U-Net进行优化,并融合三维跟踪算法,最终在电气设备图像数据集上进行了实验验证。实验结果表明,采用扩张残差网络(DRN)优化后的U-Net语义分割方法,其精确率、召回率和平均交并比相较于其他3种方法,分别平均提升了11.15%,9.40%,12.00%。在实际应用场景中,所提模型在晴天条件下表现最佳,追踪成功率高达98.8%,三维定位误差仅为0.07 m。同时,与阴天和遮挡场景相比,晴天场景下的平均处理时间缩短了51.78%。研究结果表明,所提模型可有效提高光伏电站设备实时监测的准确率,缩短处理时间,从而有效解决人工巡检方式效率低、实时性差的问题。 展开更多
关键词 u-net网络 3D跟踪算法 光伏电站 核相关滤波器
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Recent Advances and Prospects in Research of In Vitro 3D Functional Skin Tissue Models
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作者 Li Tao Zhang Liqing 《China Detergent & Cosmetics》 2026年第1期75-88,共14页
With the increasing demand for understanding skin physiology and advancing regenerative medicine,in vitro three-dimensional(3D)functional skin tissue models have become vital tools in dermatological research.These mod... With the increasing demand for understanding skin physiology and advancing regenerative medicine,in vitro three-dimensional(3D)functional skin tissue models have become vital tools in dermatological research.These models effectively mimic the complex structure and functions of human skin.This review comprehensively discusses the latest advancements in construction techniques,material selection,and applications of 3D skin models.It highlights the advantages and challenges associated with cutting-edge technologies such as layer-by-layer cell coating,3D bioprinting,bio-spray technology,and photolithographic microfabrication in creating highly realistic skin models.Moreover,it examines the wide-ranging applications of 3D skin models,includingelucidation of skin disease mechanisms,investigation of skin barrier functions,studies on skin aging and repair,hair regeneration,efficacy screening of therapeutic agents,cosmetic safety assessment,and personalized medicine.Finally,this review anticipates future trends in developing 3D skin models with greater structural and functional complexity,enhanced multifunctionality,and improved clinical translation. 展开更多
关键词 3D skin models tissue engineering BIOPRINTING skin barrier disease modeling drug screening hair regeneration skin aging
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Methods for a bioengineered 3D human brain-like tissue model of neuroregeneration after traumatic brain injury
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作者 Marly Coe Sydni Rosenfeld +2 位作者 Celia Byrne Volha Liaudanskaya David L.Kaplan 《Neural Regeneration Research》 2026年第8期3620-3628,共9页
Traumatic brain injury causes permanent cell death and can lead to long-term cognitive dysfunction,with no available treatments to repair the damaged brain tissue.Methods to track and understand traumatic brain injury... Traumatic brain injury causes permanent cell death and can lead to long-term cognitive dysfunction,with no available treatments to repair the damaged brain tissue.Methods to track and understand traumatic brain injury in humans are severely limited by the inaccessibility of living brain tissue,creating a need for in vitro model systems to study cellular mechanisms of degeneration and regeneration following injury.Here we describe methods to establish a 3D human brain tissue model,consisting of a silk-collagen composite scaffold seeded with human neurons,astrocytes,and microglia,to study neuro-regeneration after traumatic brain injury.Step-by-step fabrication,injury,and analytical assessments of the 3D“triculture”system are described.Using this tissue model system,we demonstrate that glial cells promote regeneration of neuronal networks within the injury site over several weeks post-injury.Further,we found that regenerating networks in the 3D triculture tissues did not secrete early markers of neurodegenerative disease,but displayed signs of excitatory/inhibitory imbalance,suggesting that pro-regenerative treatments for traumatic brain injury in the future may need to direct cell differentiation to promote proper function.The mechanical stability of this model system enables physiologically relevant impact injury and long-term culture capability,while its modular design enables modification of cell contents,extracellular matrix composition,and scaffold properties.This adaptability could allow the integration of patient-derived cells and genetic modifications to bridge research and clinical applications focused on personalized targeted therapies.This in vitro system provides a valuable platform for accelerating therapeutic advancements in traumatic brain injury and neurodegenerative disorders,ultimately improving patient outcomes. 展开更多
关键词 3D model EXCITOTOXICITY glial cells human brain in vitro model NEURODEGENERATION neuronal networks REGENERATION tissue engineering traumatic brain injury
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A novel nonlinear IP_(3)R state transition model and calcium oscillation
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作者 Zhao-Yu Peng Han-Yu Jiang Jun He 《Communications in Theoretical Physics》 2026年第2期202-210,共9页
We present a novel nonlinear state transition model for inositol 1,4,5-trisphosphate receptors(IP_(3)Rs)that incorporates a pre-activated state,as suggested by electron microscopy observations.Our model provides a the... We present a novel nonlinear state transition model for inositol 1,4,5-trisphosphate receptors(IP_(3)Rs)that incorporates a pre-activated state,as suggested by electron microscopy observations.Our model provides a theoretical framework for the biphasic Ca^(2+)dependence of IP_(3)Rs and accurately reproduces their experimentally observed state distribution under saturating IP_(3) conditions.By integrating receptor dynamics with cytoplasmic and endoplasmic reticulum(ER)calcium exchange,we simulate IP_(3)R-mediated Ca^(2+)oscillations governed by six key conformational states.A pivotal finding is that IP_(3)regulates these oscillations in a switch-like manner:once a critical IP_(3) concentration is reached,the system abruptly transitions to sustained,constant-amplitude oscillations that quickly terminate when the concentration exceeds a secondary threshold.These results underscore the crucial role of the pre-activated state in modulating calcium signaling. 展开更多
关键词 calcium oscillation IP_(3)R nonlinear model
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Delaminated lower slab thermal regime before slab break-off in the Pamirs:Implications from 3D kinematic modeling
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作者 Haris Faheem YingFeng Ji +6 位作者 Waqar Ahmed Rui Qu Ye Zhu Fitriani Fitriani Jun Yang Shoichi Yoshioka Nobuaki Suenaga 《Earth and Planetary Physics》 2026年第1期13-21,共9页
The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir upli... The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir uplift.Seismic imaging revealed that the upper slab was scraped and that the lower slab had subducted to a depth of>150 km.These features constitute the tectonic complexity of the Pamirs,as well as the thermal subduction mechanism involved,which remains poorly understood.Hence,in this study,high-resolution three-dimensional(3D)kinematic modeling is applied to investigate the thermal structure and geometry of the subducting slab beneath the Pamirs.The modeled slab configuration reveals distinct along-strike variations,with a steeply dipping slab beneath the southern Pamirs,a more gently inclined slab beneath the northern Pamirs,and apparent upper slab termination at shallow depths beneath the Pamirs.The thermal field reveals a cold slab core after delamination,with temperatures ranging from 400℃to 800℃,enveloped by a hotter mantle reaching~1400℃.The occurrence of intermediate-depth earthquakes aligns primarily with colder slab regions,particularly near the slab tear-off below the southwestern Pamirs,indicating a strong correlation between slab temperature and seismicity.In contrast,the northern Pamirs exhibit reduced seismicity at depth,which is likely associated with thermal weakening and delamination.The central Pamirs show a significant thermal anomaly caused by a concave slab,where the coldest crust does not descend deeply,further suggesting crustal detachment or mechanical failure.The lateral asymmetry in slab temperature possibly explains the mechanism of lateral tearing and differential slab-mantle coupling. 展开更多
关键词 PAMIRS SUBDUCTION 3D kinematic modeling slab geometry intermediate-depth earthquake crustal delamination seismicity distribution
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Automatic gating and riser system design and defect control for K4169 superalloy guide blade casting based on parametric 3D modeling-simulation integrated system
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作者 Le-chuan Li Ya-jun Yin +4 位作者 Bing-zheng Fan Guo-yan Shui Xiao-yuan Ji Jian-xin Zhou Lei Jin 《China Foundry》 2026年第1期20-30,共11页
Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical si... Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical simulation plays a significant role in quantitatively evaluating current processes and making targeted improvements,but its limitations lie in the inability to dynamically reflect the formation outcomes of castings under varying process conditions,making real-time adjustments to gating and riser designs challenging.In this study,an automated design model for gating and riser systems based on integrated parametric 3D modeling-simulation framework is proposed,which enhances the flexibility and usability of evaluating the casting process by simulation.Firstly,geometric feature extraction technology is employed to obtain the geometric information of the target casting.Based on this information,an automated design framework for gating and riser systems is established,incorporating multiple structural parameters for real-time process control.Subsequently,the simulation results for various structural parameters are analyzed,and the influence of these parameters on casting formation is thoroughly investigated.Finally,the optimal design scheme is generated and validated through experimental verification.Simulation analysis and experimental results show that using a larger gate neck(24 mm in side length) and external risers promotes a more uniform temperature distribution and a more stable flow state,effectively eliminating shrinkage cavities and enhancing process yield by 15%. 展开更多
关键词 numerical simulation automatic design investment casting parametric 3D modeling gating and riser system
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Development of Patient-Derived Conditionally Reprogrammed 3D Breast Cancer Culture Models for Drug Sensitivity Evaluation
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作者 Jing Cai Haoyun Zhu +4 位作者 Weiling Guo Ting Huang Pangzhou Chen Wen Zhou Ziyun Guan 《Oncology Research》 2026年第1期500-520,共21页
Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual pat... Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual patient responses towards different drugs.This study aimed to investigate the patient-derived breast cancer culture models for drug sensitivity evaluations.Methods:Tumor and adjacent tissues from female breast cancer patients were collected during surgery.Patient-derived breast cancer cells were cultured using the conditional reprogramming technique to establish 2D models.The obtained patient-derived conditional reprogramming breast cancer(CRBC)cells were subsequently embedded in alginate-gelatin methacryloyl hydrogel microspheres to form 3D culture models.Comparisons between 2D and 3D models were made using immunohistochemistry(tumor markers),MTS assays(cell viability),flow cytometry(apoptosis),transwell assays(migration),and Western blotting(protein expression).Drug sensitivity tests were conducted to evaluate patient-specific responses to anti-cancer agents.Results:2D and 3D culture models were successfully established using samples from eight patients.The 3D models retained histological and marker characteristics of the original tumors.Compared to 2D cultures,3D models exhibited increased apoptosis,enhanced drug resistance,elevated stem cell marker expression,and greater migration ability—features more reflective of in vivo tumor behavior.Conclusion:Patient-derived 3D CRBC models effectively mimic the in vivo tumor microenvironment and demonstrate stronger resistance to anti-cancer drugs than 2D models.These hydrogel-based models offer a cost-effective and clinically relevant platform for drug screening and personalized breast cancer treatment. 展开更多
关键词 Patient-derived breast cancer cells conditional reprogramming hydrogel microsphere 3D culture model drug screening
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From Algorithm to Expert:RLHF-Guided Vision-Language Model for 3D-EEM Fluorescence Spectroscopy Matching
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作者 Chenglong Lu Jiehui Li +5 位作者 Tonglin Chen Changhua Zhou Yixin Fan Xinlin Ren Ziyi Ju Wei Wang 《Computers, Materials & Continua》 2026年第5期1883-1900,共18页
Existing methods for tracing water pollution sources typically integrate three-dimensional excitationemission matrix(3D-EEM)fluorescence spectroscopy with similarity-based matching algorithms.However,these approaches ... Existing methods for tracing water pollution sources typically integrate three-dimensional excitationemission matrix(3D-EEM)fluorescence spectroscopy with similarity-based matching algorithms.However,these approaches exhibit high error rates in borderline cases and necessitate expert manual review,which limits scalability and introduces inconsistencies between algorithmic outputs and expert judgment.To address these limitations,we propose a large vision-language model(VLM)designed as an“expert agent”to automatically refine similarity scores,ensuring alignment with expert decisions and overcoming key application bottlenecks.The model consists of two core components:(1)rule-based similarity calculation module generate initial spectral similarity scores,and(2)pre-trained large vision-language model fine-tuned via supervised learning and reinforcement learning with human feedback(RLHF)to emulate expert assessments.To facilitate training and evaluation,we introduce two expert-annotated datasets,Spec1k and SpecReason,which capture both quantitative corrections and qualitative reasoning patterns,allowing the model to emulate expert decision-making processes.Experimental results demonstrate that our method achieves 81.45%source attribution accuracy,38.24%higher than rule-based and machine learning baselines.Real-world deployment further validates its effectiveness. 展开更多
关键词 Vision-language model reinforcement learning with human feedback pollution source tracing 3D fluorescence spectroscopy
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DNASE1L3 Mediates Hepatocellular Carcinoma Tumor Growth and Organoid Models via the Wnt/β-Catenin Signaling Pathway
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作者 Shulong Zhang Yijun Zhao +5 位作者 Li Geng Feihong Song Li Feng Jun Jiang Qianqian Cai Fei Fan 《Oncology Research》 2026年第3期691-724,共34页
Background:Hepatocellular carcinoma(HCC)is a highly lethal malignancy driven by both intrinsic oncogenic pathways and immune microenvironmental regulation.Emerging evidence suggests that DNASE1L3 may influence tumor b... Background:Hepatocellular carcinoma(HCC)is a highly lethal malignancy driven by both intrinsic oncogenic pathways and immune microenvironmental regulation.Emerging evidence suggests that DNASE1L3 may influence tumor biology and immune responses;however,its specific roles in HCC progression and macrophage-mediated regulation remain unclear.This study aimed to elucidate the biological functions of DNASE1L3 in HCC and to determine how it modulates tumor behavior and immune interactions.Methods:Bioinformatics analyses of the GSE41804 and Cancer Genome Atlas-Liver Hepatocellular Carcinoma(TCGA-LIHC)datasets were used to identify hub genes.Functional assays assessed the impact of DNASE1L3 on HCC cell proliferation,migration,invasion,and cell cycle progression.The effects of DNASE1L3 on macrophage polarization and the Wnt/β-catenin signaling pathway were examined using a co-culture system.An HCC organoid model was established to further validate its regulatory function.Results:Eight prognostic signature genes were identified,with deoxyribonuclease I-like 3(DNase I-like 3)selected as the hub gene.DNASE1L3 overexpression suppressed HCC cell growth,inhibited migration and invasion,induced G1 arrest,and modulated epithelial-mesenchymal transition(EMT)markers.DNASE1L3 knockdown promoted M2-like macrophage polarization.Mechanistically,DNASE1L3 interacted withβ-catenin to enhance its ubiquitination and degradation,thereby inhibiting Wnt/β-catenin signaling and reducing PD-L1 expression.DNASE1L3 overexpression similarly restricted organoid growth and suppressed pathway activity.Conclusion:DNASE1L3 acts as a negative regulator of HCC progression by targeting the Wnt/β-catenin pathway and reducing PD-L1 expression,thereby influencing both tumor cell behavior and macrophage-mediated immune responses. 展开更多
关键词 Hepatocellular carcinoma DNASE1L3 Wnt/β-catenin signaling pathway organoid models tumor growth
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Advanced Brain Tumor Segmentation in Magnetic Resonance Imaging via 3D U-Net and Generalized Gaussian Mixture Model-Based Preprocessing
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作者 Khalil Ibrahim Lairedj Zouaoui Chama +5 位作者 Amina Bagdaoui Samia Larguech Younes Menni Nidhal Becheikh Lioua Kolsi Badr M.Alshammari 《Computer Modeling in Engineering & Sciences》 2025年第8期2419-2443,共25页
Brain tumor segmentation from Magnetic Resonance Imaging(MRI)supports neurologists and radiologists in analyzing tumors and developing personalized treatment plans,making it a crucial yet challenging task.Supervised m... Brain tumor segmentation from Magnetic Resonance Imaging(MRI)supports neurologists and radiologists in analyzing tumors and developing personalized treatment plans,making it a crucial yet challenging task.Supervised models such as 3D U-Net perform well in this domain,but their accuracy significantly improves with appropriate preprocessing.This paper demonstrates the effectiveness of preprocessing in brain tumor segmentation by applying a pre-segmentation step based on the Generalized Gaussian Mixture Model(GGMM)to T1 contrastenhanced MRI scans from the BraTS 2020 dataset.The Expectation-Maximization(EM)algorithm is employed to estimate parameters for four tissue classes,generating a new pre-segmented channel that enhances the training and performance of the 3DU-Net model.The proposed GGMM+3D U-Net framework achieved a Dice coefficient of 0.88 for whole tumor segmentation,outperforming both the standard multiscale 3D U-Net(0.84)and MMU-Net(0.85).It also delivered higher Intersection over Union(IoU)scores compared to models trained without preprocessing or with simpler GMM-based segmentation.These results,supported by qualitative visualizations,suggest that GGMM-based preprocessing should be integrated into brain tumor segmentation pipelines to optimize performance. 展开更多
关键词 Magnetic resonance imaging(MRI) imaging technology GGMM EM algorithm 3D u-net SEGMENTATION
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Predicting Marine Heatwaves in the South China Sea Using a 3D U-Net Model Based on Intraseasonal Oscillation Signals from Atmosphere-Ocean Data
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作者 WANG Lin-hai YU Wei-dong 《Journal of Tropical Meteorology》 2025年第5期478-496,共19页
With the intensification of global warming,marine heatwaves(MHWs)have emerged as a significant extreme hazard,garnering widespread attention and creating a pressing need for accurate prediction.The development of arti... With the intensification of global warming,marine heatwaves(MHWs)have emerged as a significant extreme hazard,garnering widespread attention and creating a pressing need for accurate prediction.The development of artificial intelligence,particularly the application of deep learning to sea surface temperature(SST),has significantly improved the feasibility of predictions.This study utilizes SST and Outgoing Longwave Radiation(OLR)data to train a 3D U-Net model for predicting MHWs in the South China Sea(SCS)with lead times ranging from 1 to 7 days,based on the characteristics of intraseasonal weather processes.Analysis of MHWs occurrences from 1982 to 2023 reveals distinct seasonal patterns,with summer MHWs primarily concentrated in the northern and central SCS,and the highest temperature centers located in the Gulf of Tonkin and west of the Philippines.The 2023 MHW forecast results demonstrate that the 3D U-Net model achieves low error rates and high correlation coefficients with observational data.Incorporating OLR data enhances forecast accuracy compared to SST-only inputs,and training the model exclusively with summer data further improves prediction accuracy.These findings indicate that the proposed method can significantly enhance the accuracy of MHW forecasts. 展开更多
关键词 marine heatwaves Boreal Summer Intra-seasonal Oscillation 3D u-net South China Sea
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基于改进U-Net3+的相控阵超声图像语义分割
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作者 毛鑫玥 王慧锋 +2 位作者 周家乐 顾震 颜秉勇 《华东理工大学学报(自然科学版)》 北大核心 2025年第2期242-249,共8页
超声相控阵成像已广泛应用于聚乙烯燃气管道的焊接缺陷检测中,随着机器视觉技术的快速发展,利用机器辅助或自动化分析超声图像能极大地提高缺陷检测速度,减少人为判断失误的发生。在基于超声图像的焊接缺陷检测技术中,图像语义分割精度... 超声相控阵成像已广泛应用于聚乙烯燃气管道的焊接缺陷检测中,随着机器视觉技术的快速发展,利用机器辅助或自动化分析超声图像能极大地提高缺陷检测速度,减少人为判断失误的发生。在基于超声图像的焊接缺陷检测技术中,图像语义分割精度对缺陷类别和严重等级的判定至关重要。本文在U-Net3+网络的基础上提出一种融入残差及注意力机制的改进模型,并应用于电熔焊接缺陷检测的相控阵超声图像语义分割。首先,改进模型通过在编码器各层之间采用残差结构来提升编码器的图像特征提取能力;其次,通过在跳跃连接中引入卷积块注意力模块(Convolutional Block Attention Module,CBAM),加强模型对原始图像信息的利用率,使模型更易聚焦于原始图像中的有效区域。实验结果表明,改进后的模型在电熔焊接超声图像上具有良好的分割效果,在Dice、mIoU两项指标上,相比U-Net分别提升了8.81%和12.84%;相比U-Net3+的分割效果分别提升了1.09%和1.81%。 展开更多
关键词 相控阵超声图像 图像语义分割 u-net3+ 注意力机制 残差网络
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Solubility and Thermodynamic Modeling of 3⁃Nitro⁃1,2,4⁃triazole⁃5⁃one(NTO)in Different Binary Solvents 被引量:1
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作者 GUO Hao-qi YANG Yu-lin 《含能材料》 北大核心 2025年第3期295-303,共9页
Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging f... Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging from 278.15 K to 318.15 K.The solubility in each system was found to be positively correlated with temperature.Furthermore,solubility data were analyzed using four equations:the modified Apelblat equation,Van’t Hoff equation,λh equation and CNIBS/R-K equations,and they provided satisfactory results for both two systems.The average root-mean-square deviation(105RMSD)values for these models were less than 13.93.Calculations utilizing the Van’t Hoff equation and Gibbs equations facilitated the derivation of apparent thermodynamic properties of NTO dissolution in the two systems,including values for Gibbs free energy,enthalpy and entropy.The%ζ_(H)is larger than%ζ_(TS),and all the%ζ_(H)data are≥58.63%,indicating that the enthalpy make a greater contribution than entropy to theΔG_(soln)^(Θ). 展开更多
关键词 3-nitro-l 2 4-triazole-5-one(NTO) SOLUBILITY thermodynamic models apparent thermodynamic analysis
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Improved Medical Image Segmentation Model Based on 3D U-Net 被引量:2
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作者 LIN Wei FAN Hong +3 位作者 HU Chenxi YANG Yi YU Suping NI Lin 《Journal of Donghua University(English Edition)》 CAS 2022年第4期311-316,共6页
With the widespread application of deep learning in the field of computer vision,gradually allowing medical image technology to assist doctors in making diagnoses has great practical and research significance.Aiming a... With the widespread application of deep learning in the field of computer vision,gradually allowing medical image technology to assist doctors in making diagnoses has great practical and research significance.Aiming at the shortcomings of the traditional U-Net model in 3D spatial information extraction,model over-fitting,and low degree of semantic information fusion,an improved medical image segmentation model has been used to achieve more accurate segmentation of medical images.In this model,we make full use of the residual network(ResNet)to solve the over-fitting problem.In order to process and aggregate data at different scales,the inception network is used instead of the traditional convolutional layer,and the dilated convolution is used to increase the receptive field.The conditional random field(CRF)can complete the contour refinement work.Compared with the traditional 3D U-Net network,the segmentation accuracy of the improved liver and tumor images increases by 2.89%and 7.66%,respectively.As a part of the image processing process,the method in this paper not only can be used for medical image segmentation,but also can lay the foundation for subsequent image 3D reconstruction work. 展开更多
关键词 medical image segmentation 3D u-net residual network(ResNet) inception model conditional random field(CRF)
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A 3D attention U-Net network and its application in geological model parameterization 被引量:1
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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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IncepHoloRGB: multi-wavelength network model for full-color 3D computer-generated holography 被引量:1
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作者 Xuan Yu Zhilin Teng +6 位作者 Xuhao Fan Tianchi Liu Wenbin Chen Xinger Wang Zhe Zhao Wei Xiong Hui Gao 《Opto-Electronic Advances》 2025年第10期53-63,共11页
The popularity of deep learning has boosted computer-generated holography(CGH)as a vibrant research field,particularly physics-driven unsupervised learning.Nevertheless,present unsupervised CGH models have not yet exp... The popularity of deep learning has boosted computer-generated holography(CGH)as a vibrant research field,particularly physics-driven unsupervised learning.Nevertheless,present unsupervised CGH models have not yet explored the potential of generating full-color 3D holograms through a unified framework.In this study,we propose a lightweight multiwavelength network model capable of high-fidelity and efficient full-color hologram generation in both 2D and 3D display,called IncepHoloRGB.The high-speed simultaneous generation of RGB holograms at 191 frames per second(FPS)is based on Inception sampling blocks and multi-wavelength propagation module integrated with depth-traced superimposition,achieving an average structural similarity(SSIM)of 0.88 and peak signal-to-noise ratio(PSNR)of 29.00 on the DIV2K test set in reconstruction.Full-color reconstruction of numerical simulations and optical experiments shows that IncepHoloRGB is versatile to diverse scenarios and can obtain authentic full-color holographic 3D display within a unified network model,paving the way for applications towards real-time dynamic naked-eye 3D display,virtual and augmented reality(VR/AR)systems. 展开更多
关键词 computer-generated holography deep learning physics-driven model full-color holographic 3D display
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Building the 3D seismic fault models for the 2021 M_(S)6.4 Yunnan Yangbi earthquake:The potential role of pre-existing faults in generating unexpected moderate-strong earthquakes in southeast Xizang 被引量:1
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作者 Xiao Sun Jinyu Zhang +4 位作者 Renqi Lu Wei Wang Peng Su Guanshen Liu Fang Xu 《Earthquake Science》 2025年第3期172-186,共15页
The three-dimensional(3D)geometry of a fault is a critical control on earthquake nucleation,dynamic rupture,stress triggering,and related seismic hazards.Therefore,a 3D model of an active fault can significantly impro... The three-dimensional(3D)geometry of a fault is a critical control on earthquake nucleation,dynamic rupture,stress triggering,and related seismic hazards.Therefore,a 3D model of an active fault can significantly improve our understanding of seismogenesis and our ability to evaluate seismic hazards.Utilising the SKUA GoCAD software,we constructed detailed seismic fault models for the 2021 M_(S)6.4 Yangbi earthquake in Yunnan,China,using two sets of relocated earthquake catalogs and focal mechanism solutions following a convenient 3D fault modeling workflow.Our analysis revealed a NW-striking main fault with a high-angle SW dip,accompanied by two branch faults.Interpretation of one dataset revealed a single NNW-striking branch fault SW of the main fault,whereas the other dataset indicated four steep NNE-striking segments with a left-echelon pattern.Additionally,a third ENE-striking short fault was identified NE of the main fault.In combination with the spatial distribution of pre-existing faults,our 3D fault models indicate that the Yangbi earthquake reactivated pre-existing NW-and NE-striking fault directions rather than the surface-exposed Weixi-Qiaohou-Weishan Fault zone.The occurrence of the Yangbi earthquake demonstrates that the reactivation of pre-existing faults away from active fault zones,through either cascade or conjugate rupture modes,can cause unexpected moderate-large earthquakes and severe disasters,necessitating attention in regions like southeast Xizang,which have complex fault systems. 展开更多
关键词 Yangbi earthquake 3D seismogenic fault model relocated earthquakes Weixi-Qiaohou-Weishan fault seismic hazard
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